Pitot blocks –

                  on Climbing over read

                  on Descending under read.

Static blocks-

                  on Climbing under read

                  on Take off under read

                  on Descending over read

Altimeter

            Static blocks – shows no change in the height.

Vertical Speed Indicator

            Static blocks –

                         on Climbing under read

                         on Descending will read less than actual descent rate.

Turn and Slip Indicator

A/c taxying with left wing low.

C.G Forward – Stalling speed increases, stability increases, Controllability decreases, Nose heavy.

C.G. Rearward – Stalling speed decreases, stability decreases, Controllability increases, a/c once stall gets into Spin very easily and violent stall characteristic.

C.G. is always kept ahead of C.P.

Real wander – Real wander is a shift of gyro in relation to space, due to wear of gyro or Turbulence. It can not be calibrated, therefore no correction.

Apparent wander – Apparent wander is due to the Earth movement (also called drift) and a/c movement over the Earth.

Drift is Wander in horizontal plane @ 15.04 Sine of lat. (corrected by lat nut for each latitude)

Horizontal Axis Gyro –

            At poles max drift no topple.

            At equator no drift max topple.

Vertical Axis Gyro –

            At poles no drift no topple.

            At equator no drift max topple.

Axis N/S                    No topple

Axis E/W                    Maximum topple

In Northern hemisphere due to gyro drift the gyro readings will decrease in relation to magnetic compass.

In Southern hemisphere the gyro reading will increase in relation to magnetic compass.

A.H uses Earth gyro, which is a Vertical Axis gyro.

Artificial Horizon

1. Acceleration/Take off error- On acceleration shows a climb and right turn.
2. Turning error- Error increases up to 180⁰ turn and decreases to 0 by the completion of 360⁰ turn.

Compass Error

1. Acceleration and Deceleration error on Easterly or Westerly headings.

                    In Northern hemisphere

                                   Acceleration error- on E or W —–> shows North

                                  Deceleration error- on E or W  —–>  shows South

                   In Southern hemisphere

                                Acceleration error- on E or W   —–>   show South

                                Deceleration error-.on E or W   —–> Show North

2. Turning error – Affect only on Northerly and Southerly headings no effect on Easterly or Westerly headings.

In N/H

From N to E or W – Shows less turn. Therefore under shoot (Come out of turn early)

From S to E or W – Shows more turn. Therefore over shoot (come out of turn late)

In S/H

From N to E or W – Shows more turn. Therefore overshoot (come out of turn late)

From S to E or W – Shows less turn. Therefore undershoot (come out of turn early)

Oxidation– Oxidation to leave as little carbon as possible by oil. At high temperature fuel holds more water vapor. At low temperature fuel hold less water vapor. Temperature increases viscosity of oil decreases, therefore resistance of oil decreases.

In series voltage increases current remains same.

In parallel voltage remains same current increases.

Iso propyl alcohol decreases freezing temperature of liquid.

Ethylene Glycol Methane Eather- absorbs the water vapor and decreases the ability of fuel to hold water.

Dutch Roll– Dutch roll occurs in A/c having large Dihedral and less fin area.

Dutch Roll is more at high altitude.

            To Correct – use ailerons and yaw dampers

Spiral Instability – Spiral Instability occurs in A/c having large fin area and less dihedral.

Spiral Instability is more at low altitude.

            To Correct- use rudders.

Dihedral causes Dutch roll increases lateral stability.

Anhedral gives no stability increases control effectiveness decreases lateral stability.

Sweep back wing increases lateral and directional stability increases Critical Mach. No.

Sweep forward- gives no stability.

Wash-In-Counter acts the propeller torque, increases lateral stability and gives more lift.

At stall wing tip stalls easily and ailerons become uncontrollable.

Wash out- less stalling effect at tips therefore enabling aileron controllable at low speed and high angles of attack.

Athwartship axis —–> Lateral Axis

Helix Angle (Angle of Advance)– Angle between plane of rotation and relative airflow.

Blade Angle– Angle between chord of propeller and plane of rotation of the propeller.

Critical Altitude – Altitude at which a supercharged engine can maintain its sea level rated B.H.P.

Optimum Angle of attack– Optimum Angle of attack is used to get maximum L/D ratio. We cruise at optimum angle of attack (Lift is usually 24 times the Drag).

Wing tip vortices –

             On left wing moves in an clockwise direction

             On right wing moves in an anti-clockwise direction.

At high angle of attacks wing tip vortices are high.

Wing tip Vortices are directly proportional to Weight of the A/c and Angle of Attack.

Wing tip Vortices are inversely proportional to Speed of the A/c and Span of the A/c.

You climb maintaining same RAS, TAS increases.

Zero angle of attack– is a angle at which aerofoil produces zero lift.

–           At zero angle of attack the pressure above and below the wing is below the atmospheric pressure.

Asymmetric aerofoil usually have zero angle of attack at -4°.

Hot temperature increases Density altitude or Density altitude increases in hot temperature. High Density altitude decreases a/c performance.

On lower lapse rate, the Density altitude is higher than Pressure altitude.

Absolute pressure– Sum of atmospheric pressure and added pressure

Absolute zero – Absolute zero temperature is the Temperature at which all heat action ceases- 273⁰ c.

–           Absolute temperature can be found by adding 273⁰ to the centigrade.

Vortex generator –

1. Delays the transition point of boundary layer.
2. Prevents buffeting of a/c
3. Decreases stalling angle.

In a climb weight is more than lift, because thrust balances weight and drag component.

In a descent Lift is less than weight because weight balances lift and drag.

In a couple if drag is above thrust	—–>	A/c nose goes up.
In a couple if thrust is above drag	—–>	A/c nose goes down.
If Weight is ahead of lift	—–>	A/c noses goes down.
If Lift is ahead of weight	—–>	A/c nose goes up.

Therefore, the thrust is kept below the drag to give nose up and the wt is kept ahead of lift to give nose down movement when engine fails.

Except in seaplanes in which lift is kept ahead of weight to give nose up movement.

In a normal flight lift is usually 24 times the drag.

IMAGES

Shock Stall – Shock stall occurs at low angle of attack unlike the ordinary stall which occurs at high angles of attack. Shock stall is first noticeable due to sudden increase of drag and buffeting.

Indicated Stalling speed depends upon-

(I)         Weight

(2)       Load factor

(3)       Power

(4)       Configuration of Aircraft

Indicated stalling speed does not change with increase or decrease in altitude

Stalling occurs at a particular angle of attack, when a/c reaches this angle it stalls, whatever the airspeed.

For new stalling speed calculate old stalling speed x by square root of load factor.

Normal stalling speed x square root of load factor.

15⁰ (1.04)⁰ – 1.02      e.g. 50 stalling speed normal.

C.G Forward/ Positive – Aft/behind the datum

C.G Rearward/ Negative- Ahead/ Forward of the datum.

C.G. Rearward /Positive/Aft-

1. Stalling speed decreases.
2. Longitudinal Stability decreases.
3. Controllability increases.
4.         A/c once stalls gets into violent spin.
5.         A/c cruises faster.
6. More stable at high speeds and less stable at low speeds.
7. Fuel Consumption decreases.

C.G Forward / Negative-

1. Stalling speed increases.
2. Longitudinal Stability increases.
3. Controllability decreases
4. Nose heavy.

Compressibility error causes A.S.I. to over read therefore it is always subtracted.

Dorsal fin and Vendral fin increases directional stability at high angle of sideslips.

–                     Dorsal fin decreases the Aspect ratio of the fin.

Ultimate load factor- at which wing will break.

Yield load factor about 2/3^rd of ultimate load factor.

Classification of fire

Class  A.        Fire due to wood, clothes.

1. Fire due to petrol, oil etc.
2. Fire due to electrical.
3. Fire due to metal burning.

Halon is used to extinguish all types o Fire.

At high-speed tail plane carry download.

At low speed tail plane carry up load.

Super stall when main plane and tail plane both stall in a ‘T’ tail A/c.

During stall you loose.

1. Aileron
2. Elevator
3. Rudder.

To recover      use

1   Rudder

2   Elevator

3   Aileron

Wheel barrowing- occurs on landing with weight on nose wheels, it can also occur on Take off.

Shimmy damper- is a piston that dampens the oscillations set up due to nose wheel oscillation on Take off roll or on landing.

Stalling speed varies with square root of lift.

If Weight decreases 20% stalling speed decreases by 10%.

Mass balance is used to eliminate control flutter.

Drooped aileron is to correct Adverse Aileron yaw.

Balance tab is used to reduce the load from Pilot, they move automatically as control moves and can be checked in flight.

Anti- balance tab are used in overbalanced a/c, to provide feels of the controls to the pilot.

Static balance– is when a control surface after being repaired is checked for its C.G against manufacturer specifications, without any airflow. It must balance about its specified C.G.

            Glide Angle– is relative to airflow.

            Flight Path– is relative to ground.

Indicated H.P. = PLANK/33,000

Where

            P – Mean effective pressure lbs²./square inches.

            L- Length of stroke in feet.

            A – Area of cross section in square inches.

.           N – Number of Power strokes per minute or RPM divide 2

            K – Number of Cylinders.

Aqua Planning

1. Dynamic – Due to standing water.
2. Viscous – When surface is damp, having very thin film of fluid which cannot be penetrated.
3. Riveted Rubber – Due to rubber deposit of a/c tires on the runway.

Aqua Planning does not occur in water depth below  .2″

            1 H.P. – is 1000 pounds of weight lifted to 33foot ht in one minute.

            Or 33,000 foot pounds of work per minute,

            Or 550 foot pounds of work per second.

            I.H.P. = B.H.P + F.H.P

            B.H.P. = I.H.P. – F.H.P

Thermal efficiency is the losses suffered in converting the heat energy fuel into mechanical works.

–           It is the ratio of heat developed into useful work to the heat supplied by the fuel.

–           Rated power is less than Take off power for longer operation.

–           Rated attitude is altitude where sea level power can be maintained.

–           ISO Octane – 100% Anti-knocking value.

–           Heptane- less than 100% Anti-knocking value.

–           100 Octane – 100% Iso Octane.

            80 Octane – 80% Iso Octane + 20% Heptane

Tetra Ethyl lead– Tetra Ethyl lead is mixed in fuel to increase anti-knocking value above 100%.

Inter cooler – Inter cooler to decrease the temperature of discharge from a turbo charger it is installed after turbo charger and before carburetor.

After Cooler – After cooler to decrease the temperature of discharge from super charger it is installed after super charger.

Flat turn – A/c turns only using rudder.

Hydrometer- is used to measure specific gravity.

Flux – are Magnetic lines of forces.

            Fleming’s left hand rule- is for Generator

            Fleming’s right hand rule- is for Motor

Centrifugal flow compressor – Centrifugal flow compressor airflow is radial and therefore can have only up to 2 stages of compressor. It has large frontal area and causes more drag.

Axial flow compressor – Axial flow compressor gives more compression ratios then centrifugal compressor, airflow is straight therefore, you can have as many stages as you want, but increase in pressure is very less each stage. It has less frontal area and causes less drag.

Hot start– is when air is less and fuel is more during starting temperature, increases due to extra fuel and damages the engine, EGT rises.

False start– is when engine is rotated /cranking) without fuel and ignition, usually done to clear off any fuel left in the combustion chamber after Wet start.

Wet start– is when fuel fails to ignite and comes out of the jet pipe during starting, in this no EGT rises.

Hung Start– is when during starting if idling rpm does not increase beyond the idling rpm and remains there only.

Impulse Turbine – Impulse Turbine develops power by high velocity low pressure gas flowing through the rotor blades.

Reaction Turbine – Reaction Turbine develops its power by low velocity high pressure gas flowing through the rotor blades.

In static condition 2.6 lbs. of thrust is equivalent to be 1 H.P.

Calorific value of Petrol- 76,000 C.H.U./gal.

Calorific value of Kerosene – 83,000 C.H.U./gal.

Turbine and propelling nozzle give rearward thrust (Ventures)

Compressor, combustion chamber, exhaust unit and jet pipe gives forward Thrust.

When Engine is Static – gross thrust = Net thrust.

When Engine / A/c is in motion – Net thrust is less then gross thrust.

Choked Nozzle– Choked Nozzle is when airflow at the nozzle reaches speed of sound.

Water methanol is used in turbo-propeller a/c during Take off for restoring S.H.P.

This power is known as Wet Power.

Wet Power is with use of Water Methanol.

Dry Power is without using Water Methanol.

High Aspect Ratio Wing – High aspect ratio wing causes less induced drag and less Wing tip vortices.

Low Aspect Ratio Wing– Low aspect ratio wing causes more induced drag and more wing tip vortices.

Compressibility error causes A.S.I. to over read.

Therefore compressibility error is always negative.

Baffles are provided in the fuel tanks to prevent surging of fuel.

Swashing of fuel is due to turbulence.

Hot fuel- hot oil is allowed to go into fuel to prevent icing.

If temperature increases fuel can hold more water vapor.

Isopropyl Alcohol decreases the freezing temperature of fluid and prevents icing.

Ethylene Glycol Methyl Alcohol decreases the ability of fuel to hold water vapor in the dissolved form and absorbs water vapor.

Constant speed drive gives the constant rpm of the generator to produce electric (A.C) irrespective of engine rpm.

When constant speed drive and generator are combined in a box it is called Integrated Drive Generator.

–           Thermal runaway- is when battery is overcharged and liquid starts evaporating.

–           Ammeter shows Positive- battery is being charged.

            Ammeter shows Negative- battery is being discharged.

V₁ min (Vmcg) V1 max (VR) cannot exceed Vmbe

Vmca- max speed limit 1.2 VS (Stalling speed)

V₂ min above 1.2 of VS, landing gear up and flaps in Take off configuration and 1.1 of VMCA.

V₂ max – is subjected to Tyre speed limit

All speeds are CAS.

Vmcg- Min control speed on ground.

Min CAS during Take off run when one engine becomes suddenly inoperative it is possible to recover directional control

1. Using rudder only,
2. Rudder force not exceeding 150 lbs.
3. Assuming 7 knot Cross wind from in-operative engine side.
4. Max power on live engine.
5. Landing gear remaining extended.

VR min 1.05 of VMCA 1.10 of VS

VLOF min 1.05 of VMU

V₂ min 1.1 of VMCA and 1.2 of VS, max limit is subject to Tire speed limit.

            V Ref. = 1.3 VSO (Stall speed in landing configuration)

For turbo propeller A/c factored landing distance-

            For Destination         A.L.D. ÷ 6 = L.D.R.

            For Alternate              A.L.D. ÷ 7 = L.D.R.

L.D.A. should always be above L.D.R.

In wet runway the screen ht is decreased to 15 feet.(Instead of 35″) We increases the dist by 15% for T/o and landing on Wet runway.

In performance dist calculation (½) 50% of headwind and 150% (1.5%) of tail wind is measured.

Take off Distance Required–

From standstill to ref zero (35″) dist of two-engine t/o is measured and increases by 15% or by 1.15.

Then one engine failure t/o dist to screen height is checked and whichever is higher is taken as TODR.

Take off Run required

TORR – T/o run required is greater of the following

(a)       Dist from standing point till the mid point (*) between the point of lift off and the point where a/c reaches 35″ height and speed V2. If a/c maintains a steady rate of climb it should have reached 17.5 feet by the point.

With following conditions-

1. All engines on Take off thrust fill V1.
2. Critical engine inoperative at V1 and remaining engine continuing at Take off thrust.

Or

(b)       115% or 1.15% of the dist from standing start to the mid point (*) between point of lift-off and the point where a/c reaches 35″ height and speed V2 with all engine on t/o thrust.

            15% more of both engine acceleration distance.

Whichever value of (a) and (b) is more is taken as the TORR.

LDR landing distance required is 1.67% or 1.67 times the distance required during normal landing to land from 50′ above the threshold at VREF and coming to a complete stop (following a steady descent to 50″ feet point at a descent gradient of not more then 5% and at speed not less then VREF) on a dry level surface under I.S.A. conditions.

Transponder uses all codes from 0000 to 7777 using all no’s except those containing 8 or 9.

For Air conditioning- at high power settings air is taken from LP or IP bleed air.

At low power settings air is taken from H.P. bleed air.

In a Symmetrical aerofoil the stalling angle of attack is more than Asymmetric aerofoil.

Although the lift is more in a cambered (Asymmetric) aerofoil, but the stalling angle of attack is less.

Critical Mach no is always less than ONE.

Air above the wing velocity increases, pressure decreases, air tends to move Inward and Forward. (Air goes from high to low pressure). Air below the wing velocity decreases pressure increases, air tends to move outward and backward/ rearward.

Air from below the wing (High pressure) tries to get on to the top of the wing (low pressure) (Air goes from high to low pressure) causes wing tip vortices to form at the wing tip.

In high Aspect ratio wing, stalling angle is less as compared to low Aspect ratio wing.

High aspect ratio wing has less Induced drag and less wing tip vortices.

The distance on earth at 60⁰ N/S is exactly half of the Equator.

Over Delhi Sun is never overhead.

            Calcutta once a year.

            Bombay twice a year.

            0 to 23 and a 1/2  North or South comes overhead

21st June- Summer Solistice- longest day in Northern Hemisphere Sun is at 23°30” North.

22nd December – Winter Solistice – longest night in Northern Hemisphere Sun is at 23°30” South.

21st March – Spring Equinox- Day = Night, Sun at Equator.

22nd/23rd September- Autumn Equinox- Day = Night, Sun at Equator.

In subsonic airflow –

In Convergent nozzle velocity increases pressure decreases.

In Divergent nozzle velocity decreases pressure increases.

In super sonic flow-

In Convergent nozzle velocity decreases pressure increases.

In Divergent nozzle velocity increases pressure decreases.

In jet engine thrust remain constant but THP increases with velocity of a/c.

In a propeller engine the power remains constant and thrust output varies with the velocity of a/c.

As velocity increases THP increases up to a certain limit and then decreases.

In jet engine altitude increases, N2 increases which causes N1 to increase.

When gases pass through the turbine, temperature decreases, velocity decreases, pressure decreases.

Primary air goes to the engine.

Secondary air is by passed air.

At shock wave, velocity decreases, pressure increases, temperature increases, density increases.

In a Climb lift is less than weight.

In a descent lift is less than weight.

In an a/c maneuver lift is more than weight.

Change of angle of attack in a Symmetrical aerofoil, Cp. does not change.

Auto Pilot/INS- uses Space gyro, or Ring Laser Gyro, when it uses Ring Laser gyro the erection time is reduced to 10 minutes as compared to 30 minutes with Space gyro.

Erection time- time taken by the gyro to become fully operational..

D.G.I. – uses a Tied gyro, which is a Horizontal axis gyro, with freedom in 55° either side.

A.H. (A.I.) – uses a Earth gyro, which is a vertical axis gyro

T.S.I- uses a Rate gyro, which is a horizontal axis gyro.

Irreversible Controls – Irreversible Controls can be moved by from cockpit but not from outside, e.g. wind gusts cannot move controls

Example:- Hydraulic controls, spring tabs etc.

–           Magnetic Equator = Aclinal = lines joining places of zero dip.

–           Dip is 0 at equator and is max at poles.

–           Tetra Ethyl lead is added in fuel to prevent detonation.

–           Tetra Ethyl lead increases anti-knocking value of fuel above 100%.

Whenever Rate of Climb changes, Angle of climb also changes.

When Angle of climb changes, Rate of Climb may or may not change.

* Rate of Climb does not depend on wind velocity.

*Angle of climb depends on wind velocity.

In Head wind angle of climb increases.

In Tail wind Angle of climb decreases.

With flaps Angle of climb decreases, Rate of Climb decreases.

Neutral point is that point of C.G at which stability is nil. Therefore, C.G should always be ahead of neutral point.

–           A 10% increase in weight, stalling speed increases by 5%.

            A 10% decrease in weight, stalling speed decreases by 5%.

Canti lever wing has no external support.

Semi-Cantilever wings has external supporting structure known as struts.

Longitudinal Dihedral is different between Main plane and Tail plane.

High keel surfaces are all vertical surfaces above the Centre of Gravity.

In a spin A/c is pitching up yawing and rolling, the a/c is in a stall with low airspeed.

To recover apply opposite Rudder.

In a spiral A/c is pitching down, yawing and rolling, but the a/c is not stalled and airspeed is high, therefore, be careful not to exceed structural limit speed.

To recover apply opposite Rudder.

Volumetric efficiency is ratio of Weight of fuel/air mixture supplied to the engine to the value of weight of fuel/air mixture that would have been drawn inside the engine under standard conditions of temperature and pressure theoretically

Spark Plug fowling occurs due to low rpm and rich mixture.

Balance tab decreases the feel of controls.

Anti-balance tabs increases the fuel of controls, and are used in overbalanced A/c.

If humidity increases, density decreases.

Or

If humidity decreases, density increases.

When alternate static source is used, the A/c Altimeter and Airspeed indicator will over read because the cockpit pressure in an un pressurized A/c is less than the atmospheric pressure. Therefore altimeter over reads, V.S.I. will show a increase and then settle down.

Apparent drift – 15⁰ per hour at North Pole.

            + 15⁰ per hour at South Pole.

 It varies proportionately in mid latitudes and is zero at Equator.

Servo Tab – on moving controls columns, control surface does not move, only tab moves, therefore, full and free movement of control surface are checked as an external check.

            Temperature decreases, Relative humidity increases.

            Temperature increases, Relative humidity deceases.

In pre-flight –

            Servo Tab                              stick back (up)

            Elevator will not move.

            Tab moves.

Balance Tab                          stick back (up)

            Elevator moves up

            Tab moves down.

Spring Tab                             stick back (up)

            Elevator moves up

            Tab does not move.

Jack Stall – Jack stall takes place at very high Mach No., due to formation of shock waves, especially in ailerons, and controls do not move. It occurs because there is adverse pressure distribution around the jacks which move the controls.

Longitudinal axis– is Fore and Aft axis.

Lateral axis– is Athwart ship axis.

Aerodynamic Center is a point on the chord of the wing at which the total reaction of the aerodynamic forces on the aerofoil can be considered to act. It is a total reaction of aerodynamic force acting at a single point on the chord line. A.C. does not move and is fixed.

Aerodynamic Centre is usually at 25 % behind the leading edge in Sub sonic A/c.

Aerodynamic Centre is usually at 50 % behind the leading edge in Super sonic A/c.

Aerodynamic Centre moves forward, or is less than 25 % behind leading edge, only with increase in Wing Thickness

Under all condition of flight C.G is kept ahead of C.P.

Perigee – Point where Sun is closest to Earth.

Apogee – Point where Sun is farthest from Earth.

Moon Waxing – Moon Increases in size.

Moon Waning – Moon Decreases in size.

Moon cycle has 4 quarters.

In 1 and 2 Moon is waxing, it increases in size.

In 3 and 4 Moon is waning, it decreases in size.

Compressibility error is at speeds above 300kts.

Mach meter is a combination of A.S.I. and ALTIMETER.

Effect of position error is maximum in Mach meter.

In Mach meter

            Static Blocks-

            A/c descending Mach meter over reads.

Super Critical Aerofoil – Super Critical Aerofoil is a wing shape for super sonic A/c, speed increases instead of Shock waves, Expansion wave forms, and when air passes through them velocity increases, pressure decreases, density decreases, temperature decreases (instead of increasing as in Shock waves) because air is expanding. Stock waves form ahead of the a/c.

No change in velocity and pressure, because Shock wave does not form.

Carburetor icing takes place due to adiabatic cooling, that is why it is possible at + 20⁰ c (+20⁰ c to – 10⁰c).

Anti-icing – is used to prevent ice-formation.

De-icing – is used to remove ice that has formed.

In A/c magneto system, the coil remains stationary and magneto rotates.

            Each fuel tank has sump to collect impurities.

            Each fuel tank has drain-to-drain impurities.

            Fuel tank has baffle plates to prevent surging of fuel.

Shock wave forms when a/c passes super sonic to sub sonic i.e. 1.2 to 0.8 and not from sub sonic to super sonic at to 1.2.

In Shock Wave – Velocity deceases pressure increases temperature increases density increases.

(Example- when on a red light a car slows down, its velocity decreases the no. of cars increases, density increases, due to mass, pressure increases and due to heat of big masses temperature increases.)

Aileron Droop – Aileron Droop is when aileron goes down/extend as flaps and then works an aileron also. (whole leading edge shape moves lower as flaps)

Rime Ice – Rime ice forms due to super cooled H² o droplets in the atmosphere and when the a/c passes through them, the equilibrium is disturbed and ice is formed.

Clear/Glazed Ice – Clear/Glazed Ice forms when A/c passes through area of super cooled rain or when cold a/c passes through rain. This type of ice is transparent and cannot be detected easily from the cockpit; the rate of formation is much higher than the rate at which it melts.

It is most dangerous type because-

1. Difficult to locate (only indication is that speed decreases for no reason)
2. Forms on places where De-icing is not present.

            Remedy – To get rid – fly at a lower level.

Hoar Frost – Hoar frost is white milky in color, uniform deposit of ice on the a/c body. It forms when a/c is parked on the ground, at night or in a prolonged taxi.

            It is soft and brittle and can be removed easily.

It must be removed before Take off since it can change the shape of the aerofoil significantly and cause tremendous Drag.

Weight is another factor that adds to degrade A/c performance

Temperature increases S.G decreases.

Warm fuel is lighter, cold fuel is heavier.

Lift provides upward force, this force causes stress on wings. Therefore, fuel in the wing gives a down ward force counter-acting this upward force.

Oil pressure gauge works on Bourdon tube principle.

On rubbing glass rod with silk glass becomes positive and silk becomes negative.

On rubbing ebonite with wool Ebonite becomes positive and wool becomes negative.

Piston Engine – Piston Engine is a constant volume cycle, it is also known as OTTO cycle.

Jet Engine – Jet Engine is a constant pressure cycle, it is also known as Brayton cycle.

Thrust levers (Jet Engine) controls – Fuel flow.

Throttle controls (Propeller Engine) controls – Airflow.

In case of Compressor stall rpm decreases, EGT increases or fluctuates.

In case of Engine failure rpm decreases, EGT decreases.

It takes less energy to compress 1 pound of cold air as compared to compress 1 pound of warm air.

• Therefore as altitude increases less energy is required to compress air by the compressor, but energy from the turbine to run high press compressor is same.

Since N₂ is governed by fuel flow. We decrease fuel flow to decrease N.H

As altitude increases less energy is required to compress air by the compressor but energy from the turbine is same to run the high pressure compressor, we don’t want this to happen, NH/N₂ is governed by fuel flow, we decrease the fuel flow to decease rpm and not allow rpm to increase, NL depends on NH, we are indirectly controlling the NL (Low pressure compressor)

By controlling NH we control NL but as altitude increases, OAT decreases NL rpm increases.

As altitude increases density decreases, this is compensated by increase in N₁ rpm, which causes greater mass of air to move into compressor.

As altitude increases mass of airflow through engine decreases, therefore, thrust will decrease.

Turbines under goes very high Thermal and Centrifugal stresses.

EPR – EPR is ratio between the pressure outlets of the Compressor to the pressure at the inlet of the Compressor.

If landing gear retract back ward C.G moves backward.

Hydroplaning of nose wheel nose wheel becomes in effective in wet runway

Airborne weather radar measures precipitation, not turbulence.

Generally precipitation increases, turbulence increases.

Dip is angle of inclination of a freely suspended magnet with the horizontal plane.

Dip is 0 at Equator and Dip is maximum at poles.

International N.M. as defined by ICAO measures 1852 meters.

Body water line – is the height of A/c from the ground.

Body buttock line – is the lateral distance of wings from the centerline of fuselage

Magnus – is the Air moving above and below the wings.

When flaps are extended the lateral stability decreases causing easy Maneuvering/ Controllability of the A/c.

At high temperature tire expands therefore pressure in tire increases.

At low temperature tire contracts therefore pressure in tire decreases.

When pressure is low boiling point is low

When pressure is high boiling point is high.

If fuel tanks are not vented, and outside atmospheric pressure is low, fuel will be sucked out.

On turning HP off- Engine switches off immediately.

On turning LP off- Engine runs for some time before switching off.

Fuel is stored in Inboard wing tank and outboard wing tank, first we should consume inboard tanks and then outboard tanks.

When a jet engine starts the HP compressor moves first.

Surge bleed valve works automatically to avoid stall.

To burn one kg of fuel, 17-18 kg of air is used.

I.T.T. is between H.P.T. and L.P.T.

Temperature increases F.C. increases, power decreases, turbine temperature increases.

Flat rated power is when power remains constant up to a certain temperature and beyond that power decreases (only used for Take off) only at ISA +15⁰ c.

Thrust decreases with increase in speed, maximum in turbo-propeller than turbo jet/fan.

Centrifugal force tends to send propeller to fine pitch.

ATM becomes CTM during dive.

Halon is used as fire extinguishing chemical on liquid fire, deodorant Electric fire general combustible material (paper etc).

Compression ratio- is ratio of cylinder volume, when piston is at BOC, to the area when piston is at TOP DEAD CENTRE

Valve overlap occurs at end of Exhaust stroke.

Valve springs are duplicated to decrease valve bounce and increases safety.

Clearance volume is the area between piston head and cylinder head when piston is at Top Dead Centre

Peak gas pressure in a cylinder occurs just before ignition /power stroke.

Priming is filling the system with fuel and not pressurizing it.

Throttle controls airflow to the engine/ carburetor.

Slow running jet is for low idle throttle settings.

Power jet is for high/full throttle setting.

Enrichment jet is for short period high power settings, like on T/o.

Cut out value is to turn off the engine, and stop the slow running jet to provide fuel at low throttle settings.

In carburetor engine as altitude increases mixture becomes rich due to low weight of air.

Mixture once entered into inlet manifold under pressure from the impeller is normally referred to as Manifold Pressure .

High MAP causes detonation.

Convergency is inclination between two meridians.

In Air Almanac Moon set/Moon rise timings are given in UTC.

In Air Almanac Sun set/Sun rise timings are given in LMT.

Induced drag decreases in ground effect.

In ground effect A.S.I. under reads because static pressure is high.

Squalls are of larger duration than gusts.

            Squalls above 25 knots.

            Gale above 33 knols.

            Hurricane above 63 knots.

–           Katabatic winds at night on down slope of mountain.

            Katabatic winds are stronger than anabatic wind.

–           Anabatic wind at day up slope of mountain.

–           Fohn wind flows down slope of mountain, it is dry wind.

–           If Isobars are closer together, the pressure gradient is steeper and winds are stronger.

Haze is when Visibility falls below 4000 meters but is above 2000 meters due dust particles.

Mist is when Visibility falls below 2000 meters but is above 1000 meters due water particles.

Fog is when Visibility falls below 1000 meters due water particles.

Smog is when Visibility falls below 1000 meters due dust particles.

Hachures are tilled lines, which point towards high features.

While refueling in wing tanks, the inboard tanks should always be refueled before outboard tanks due to wing root structure loading stress limitations.

Stiffener is provided in a/c fuselage to take care of extra stress.

On high wing A/c if fuel caps are not placed. In flight when the velocity in high and pressure low at top of wing, (the air tends to flow from high to low pressure) all the fuel will be siphoned out very quickly.

When temperature decreases fuel density increases, fuel compresses volume decreases.

When temperature increases fuel density decreases fuel expands, volume increases.

Fuel is filled in tanks by volume and engine consumes fuel by weight.

In centrifugal flow compressor airflow is radial and therefore can have only two stages of compression. Large frontal area causes drag.

Bleed air/compressor surge bleed value- to avoid compressor stall.

Lift is always perpendicular to relative airflow.

Isochrones some phenomenon occurring over and over at the same time.

Isopleths lines joining places of equal value having some data.

Rejected T/o – stop until runway.

Aborted T/o – stop with in ASDA.

In a Mach meter static is used twice therefore the position error is max on the mach meter.

Apparent drift in gyro of –15 per hour at North Poles and +15 per hour at South Pole varies proportionately in the intermediate latitudes and is 0 at Equator.

            Isobar = Equal Pressure

            Isotherm = Equal temperature

            Isohygric = Equal humidity

            Isohytes = Equal rainfall

            Isogones = Equal wind direction

            Isotach = Equal wind speed

            Isallobars = Equal pressure change

            Isopleths = Lines joining places of equal value having same data

Isochrones = some phenomena occurring over and over at same time

            Isohumes = Equal relative humidity

Alternator –A.C. generator.

Generator – D.C. generator.

Ammeter shows generator current.

Ammeter shows positive, battery is being charged.

Ammeter shows negative, battery is being discharged.

For TCAS III installation A/c must have mode ‘S’ transponder.

For Air conditioning, at high power setting the air is taken from L.P. or I.P. bleed air.

At low power setting air is taken from H.P. bleed air.

In a/c, the temperature near the feet should be warmer then the temperature near the head level. Therefore, the hot air is provided from the floor out let and top outlet provides cold air.

If a/c maximum difference pressure increases safety release valve automatically releases pressure.

During a rapid descent the inside pressure may be less than outside pressure. In this case the a/c may collapse.

Negative pressure relief value opens allows the atmospheric pressure to go inside the cabin, anytime the inside pressure is below –0.3 the atmospheric pressure.

Dump value is to dump any positive pressure of cabin on landing, if a/c lands pressurized sensing weight on wheels.

The rate of descent of density is very high in Tropopause and Stratosphere as compared to troposphere.

Atmosphere consists

78% Nitrogen

21% Oxygen

1% Helium and other particles

High Aspect Ratio wing has less stalling angle.

A high aspect ratio wing has less drag as compared to low aspect ratio wing.

Minimum Drag Speed gives the best rate of climb.

If difference between the drag and thrust is maximum we get best ROC.

Climbing is measured with angle of attack only not angle of Incidence.

If angle of attack is 5⁰ and angle of incidence is 5⁰

Climbing angle will not be 10⁰, it will be only 5⁰

Wing lets are very useful at low speeds

T/o power requires less with winglets.

Therefore use of winglets is very crucial below minimum drag speed.

Full moving tail plane increases C.G range.

For a given angle of attack the CL  is higher for a cambered aerofoil.

Vmcg – If one engine fails it is possible to recover direct control and continue take off if a/c is above this speed-

(a)       Using rudder only force up to 150 lbs.

            (b)       Assuming 7 knots wind from in-operator engine side.

            (c)        Without decreasing thrust on live engine.

            (d)       Leading gear extended.

–           Vmca – Min speed at which if engine it is possible to maintain directional control and continue T/O

            (a)       Rudder force up to 150 lbs.

            (b)       Bank up to 5 days.

            (c)        Directional change of max 20⁰.

            (d)       Without decreasing thrust on live engine.

            (e)       A/c airborne and with negligible ground effect.

            Maximum Vmca speed limit 1.20 vs.

–           V₁ – Decision speed at which it is possible to t/o and achieves V₂  by 35” ht within TODA.

Or at which it is possible to abandon t/o and bring the a/c to a complete stop within ASDA.

            Min V₁– Vmcg                        Max V₁ – VR (V₁ cannot exceed Vmbe)

–           V₂ – Speed that has to be attained by 35 feet height during T/o and which ensures 15⁰angles of bank maneuver capability and specified safety margin in relation to stall and control of a/c during t/o on one engine.

Min V2 – 1.1 Vmca, 1.2 VS (Stalling speed with flops on t/o and gear up)

            Max tire speed limit.

However under condition of high temperature at high pressure altitudes, the A.S.I. over read due to change in pressure error. This is allowed for by tabulating higher speeds as Vr. In such a case Vr. is increased by 1Knot or so higher then V₂.

VLOF- (Lift off speed) – Speed at which a/c lifts off ground when rotated at Vr. Min VLOF –1.05 Vmu.

Max value of VLOF is governed by tire speed limit.

C.G should always be ahead of neutral point.

C.G behind neutral point stability decreases, easy to maneuver a/c.

Aerodynamic center is pt/position where pitching moment is constant.

With variable incidence tail plane the neutral point can be changed and trim drag also decreases

If C.G is too forward or too rearward the rudder is in effective.

If C.G is slightly forward the rudder becomes more effective.

In dihedral wing the effect of engine failure is more, due to increase lateral stability, roll causing yaw and yaw causing further roll.

Anhedral increases control effectiveness, and decreases lateral stability.

C.G position change affects longitudinal stability only.

Flaps movement, flaps increases decreasing lateral stability only a/c easy to maneuver on roll/lateral axis.

Nitrogen gas is used to fill tire pressure.

Therefore temperature-increases tire expands.

Temperature decreases tire contracts.

Flash point – Flash point is when fuel goes in air as a vapor.

Boiling point decreases with decrease in pressure.

Oxygen system

(1) Normal – Oxygen and cockpit air both mix and then goes on demand.

(2) 100% Oxygen flows from cylinder in case of smoke- on Demand.

(3) Continuous flow emergency – 100% continuous flow.

Flying at altitudes 10,000- 14,000 feet or pressure level of 700 – 640. It is required to carry oxygen for all crew and 10% of passengers.

In ground effect A.S.I. under reads due to high static pressure.

When alternate static source is used, the altimeter over reads because in an un pressurized A/c cockpit (the place where alternate static is measured) the value of static is less than actual static.

DALR value reduces @ 3° Celsius per1000 feet.

SALR value reduces @ 1.5° Celsius per 1000 feet.

ELR> DALR means Absolute instability.

ELR = DALR means Neutrally stable for dry air and unstable for saturated.

ELR = SALR  Neutrally stable for saturated air and stable for dry air.

ELR < SALR Absolute stable.

ELR increases stability decreases, ELR decreases stability increases.

Inversion is a stable layer.

            NOTAM

            Class I- Distribution by Telecommunication.

            Class II- Distribution is by means other than Telecommunication.

Series A – More than 2 hours

Series B – Less than 2 hours

Series C – Domestic

Series D – Defense.

Series G – More than one FIR, issued from Delhi, Widest possible publicity.

NOTAM

            N – New Information.

            C – Cancel previous information.

            R – Replaces previous information.

Condensation – water vapor forms into water droplets.

Sublimation – water vapor forms into ice crystals.

At a low pressure area winds converge and convergence is followed by the ascent of air.

Therefore, rising air gives indications of Instability.

Therefore, sinking air gives indications of Stability.

Radiation fog forms when at night –

            (1)       Winds are calm.

            (2)       Sky is clear.

            (3)       Sufficient moisture in atmosphere to effect condensation.

If winds are 0 or in no winds cooling will be confined to the surface of the earth and dew will form instead of radiation fog.

If winds are stronger the lower temperature winds are lifted to higher levels, therefore condensation will occur at higher levels in form of status clouds and not radiation fog.

Advection fog – Warm moist air from sea area moves towards cooler sea or land areas. It can form at any time of day or night.

Relative humidity – Ratio between amounts of water vapor present in the atmosphere to the amount of water vapor it can hold when saturated at the same temperature. It is expressed in percentage.

Dew point – Dew point is temperature to which air must be cooled to become saturated.

Black hole illusion – Approaching to land on a dark place in night with no lights on runway with only the distant runway or airport lights to provide usual stimulation. Even the most experienced pilot may under shoot the runway and  tend to land short of the runway.

Katabatic wind – At Night down slope of mountain

Anabatic wind – At Day up slope of mountain

Sea breeze – At Day

Land breeze – At Night

Air masses

(1) Polar Maritime – Polar maritime form over sea areas, in Polar Regions. It is cold and moist.

(2) Tropical Maritime – Tropical maritime form over sea areas, at Mid Latitudes. It is warm and moist.

(3) Equatorial Maritime – Equatorial maritime form over sea areas, at Equator. It is very warm and very moist.

(4) Polar Continental – Polar continental form over land areas, in Polar Regions. It is cold and dry.

(5) Tropical Continental – Tropical continental form over land areas, in Mid Latitudes. It is dry and warm.

Trend type landing forecast is valid for 2 hours from observation.

Terrestrial radiation – Terrestrial radiation is the radiation of solar energy (Sun waves) sent back by the Earth.

Diurnal Radiation– Diurnal radiation in day solar radiation exceeds terrestrial radiation and surface of earth becomes warmer. At night solar radiation ceases but terrestrial radiation (Solar energy sent back into space by earth’s surface continues) and cools the surface, warming and cooling of the atmosphere occur as a result of Diurnal radiation.

VA is design-maneuvering speed for maximum range, (when maximum miles/per lb of fuel) is required.

The co-efficiency of lift of sweep back wing as compared to rectangle wing is less. Therefore, for the same lift produced the sweepback wing a/c are flown at higher angle of attack.

A/c category- By approach speeds Vref = 1.3 VS in landing configuration.

            A – below 90 knots.

            B – 90 –120 knots.

            C – 120 – 140 knots.

            D – 140 – 166 knots.

            E – Above 166 knots.

Cat E contains only certain Military a/c and are not included in the Jepessen Data/Approach charts.

V18

V₁₈ – Engine failure speed for balance field length- speed at which, if on engine occurs, the dist to continue the t/o to a ht of 35” is equal to the dist to stop under zero r/w slope, and zero wind conditions.

Vat – is speed at threshold based on 1.3 times stall speed in the landing configuration at maximum certificated landing mass.

DA – Decision Altitude – is with reference to mean sea level.

DH – Decision height – is with reference to airport elev.

DA – 1440’    DH – 200’      R/w elevation can be calculated to be 1240’

Minimum IFR Altitude – Minimum altitude for IFR operations are given in aeronautical chart for airways, routes and for standard instrument approach procedures.

If no applicable min altitude is given, the following min IFR altitude apply-

1. In mountain areas, A/c should be 2000’ feet above the highest obstacle with in a horizontal distance of 4 nm from the course to be flown.
2.      In plain areas, A/c should be 1000’ feet above the highest obstacle with in a horizontal distance of 4 nm from the course to be flown.

            OR      as otherwise authorize by the ATC.

Minimum Enroute Altitude- gives obstacle clearance of 1000 feet over plain areas, and 2000 feet over mountainous areas, it gives Navigation/ Communication coverage in all route segment

Minimum Obstruction clearance altitude.

–           MOCA – MOCA gives obstacle clearance of 1000 feet over plain areas, and 2000 feet over mountainous areas, it gives Navigation/ Communication coverage only up to 22 nm.

Whereas the MEA gives reliable signal coverage along the whole route or segment.

Therefore, ATC will assign MOCA only when the a/c is close or with in 22 nm of the navigational aid.

–           MORA – Minimum Off Route Altitude – gives obstacle clearance of 1000 feet over plain areas, and 2000 feet over mountainous areas, it gives obstacle clearance with in 10 nm of the route centerline.

            MRA – Min Reception Altitude – lowest altitude at which an interception can be determined.

–           MSA – Min. Safe Altitude- is altitude shown on approach charts providing 1000’ feet obstacle over plain and Mountainous areas, it gives obstacle clearance with in 25 nm of Navigation facility, unless some other dist is specified.

The 1000’ foot criteria apply over both mountains and non-mountains terrain. MSA may be ÷ into many sections or redials.

            Each MSA is applicable only to the approach on which it is displayed and it cannot be used for any other approach.

            Factors of MSA-

1. It only gives obstacle clearance with in the sector neither Navigation nor Communication coverage is guaranteed.
2. MSA is not listed for every approach. Its omission may be due to lack of an easily identifiable facility upon which to orient the MSA circle

H         HIWAS – Hazardous in flight weather advisory service – Continuous broadcast of hazardous weather information.

T          TWEB – Transcribed Weather Broadcast – Continuous recording broadcast of meteorological and aeronautical information on LF/MF and VOR facilities for pilots.

Touch down zone elevation is the highest elevation in the first 3,000’ of the landing surface.

(M)      Met. Report required.

Indicated Stalling speed depends on

1. A/c wt.
2. A/c configuration
3. C.G location

                        C.G forward stalling speed increases.

                        C.G rearward stalling speed decreases.

4. Load factor.

CAT – Clear air turbulence is usually on countered with Jet streams above FL150.

CAT can some times be identified visually on flights by long streaks of cirrus clouds.

A common location of CAT is an upper trough on the poles side of a jet stream.

CTM (Centrifugal Twisting Moment) – tends to decease the pitch of propeller.

ATM (Aerodynamic Twisting Moment) – tends to increase the pitch of propeller.

Ground position – Position of A/c on the ground, directly beneath the A/c.

Pin point – Ground position of A/c taken by the direct visual reference of the grounds.

Fix – Ground position of A/c taken by means other than the direct visual reference of the ground.

Dead Reckoning – Ground position of A/c calculated by known data regarding the progress of the flight. It is only the estimated position of the A/c.

Air Position – Ground position of A/c not affected by wind velocity.

Air Speed – Speed of A/c in relation to the relative airflow.

Ground Speed – Speed of A/c in relation to the ground.

In A.S.I. compressibility error is only error that causes A.S.I to over read

As altitude increases compressibility error also increases and A.S.I. over reads.

In VHF bands and above /Super Refraction/ Duct propagation occurs when inversion of temperature in lower layers close to earth occurs, reflecting radio waves as ionosphere layer.

NDB – Vertically polarized signal

Where, Electro Static component is vertical.

            Electro Magnetic field is horizontal.

            NON A ₁ A – Un modulated call sign

NON A ₂ A –Modulated call sign.

Servo Tabs – Servo tabs are connected to control columns and not to control surfaces directly therefore moving control column moves tab only and not the control surfaces.

Spring Tabs – Spring tabs are connected to control surfaces via spring tabs. Therefore, moving control column moves control surfaces only and not tabs. Only wind loads can move tabs in flight.

Induced drag occur-

1. Because high pressure air below the wing comes over the top of the wing to get over low pressure air causing vortices to form – wing tip vortices.
2. Leading edge of wing has up wash and part of it has down wash the trailing edge wing has up wash on bottom and down wash on the top surface of the wing causing eddies to form and going outwards, they meet wing tip vortices to wing tip and further strengthen the wing tip vortices.

As finess Ratio increases, induced drag decreases.

Vmd – Min drag speed.

At Vmd induced drag = Parasite Drag.

Lift varies as square of velocity as airspeed.

If airspeed increases 3 times ( 3² = 9) lift increases 9 times.

Power ‘ON’ stalling speed is less than power ‘OFF’ stalling speed because of 2 reasons-

1. With Power ‘ON’; thrust is divided into 2 parts one is in direction of flight other is in direction of lift.

Therefore lift requirement decreases and stalling speed with power ‘ON’ decreases.

2. In a Tractor propeller driven engine the slipstream caused by the propeller re-energies the boundary layers and pusher the transition layer backward therefore, boundary layer is re-activated on the aerofoil causing stalling speed to decrease in power ‘ON’ stall.

Theoretical pitch – Practical Pitch = Slip

Hypoxia – loss of O2 (Oxygen) in blood cells with increase in height

Jet Engine Starting 1 Starter 2 Ignition 3 Fixed.

Min visibility required for NDB approach in 3700 meters.

Jet engine power is measured in lbs of dynamic thrust.

Alt setting when set to zero shows Ambient pressure.

Valve clearance set too wide-causes loss of engine power.

Successful start of jet engine is known by Rise in EGT.

Fuel is stored in tanks by volume and is consumed by engine by weight.

For farther glide (Maximum range) fly A/c at best L/D ratio speed and angle of attack for best L/D ratio.

Wind velocity- W/V does not affect ROC (upwind or downwind). It affects flight path gradient.

Head wind increases Flight path gradient, therefore AOC decreases.

Tail wind decreases Flight path gradient therefore AOC increases.

Service Ceiling – Altitude where ROC drops to 100 feet per minute.

Absolute Ceiling – Altitude where ROC drops to 0 feet per minute.

–           Angle of climb is governed by thrust in excess.

–           Rate of climb is governed by power in excess.

–           Pendulum effect – In high wing a/c the wing in a turn tends to come back to level flight by coming at same angle of bank.

–           Critical Mach no. – Speed of air that reaches speed of sound Mach 1 at any point on the aerofoil of the a/c.

–           As thickness of aerofoil increases, Critical Mach number decreases.

–           Therefore, a lower thickness ratio is chosen for wings of a/c flying at high speeds.

–           On sweep back wing A/c at high speeds, there is a twisting tendency on the tip, which decreases the angle of attack at wing tip. To compensate this, the A/c nose goes up and this will increase the ‘G’ loads (Gravitation loads.)

–           On the contrary the straight wing A/c will not twist, but it will bend.

–           Sweepback wing A/c at same angle of attack as compared to straight wing A/c produces less lift and therefore the ‘g’ loads are also less.

–           Sweep back wing A/c are more useful at high speeds than low speeds.

–           In sweepback wing A/c the wing, which drops, has a more aspect ratio than the other.

–           Sweepback wing gives-

1. Lateral stability.
2. Directional stability.
3. Higher Critical Mach number (because it gives less lift)

FDTL – Applies to all Crews

            8 hours – In 24 hours.

            30 hours – In one week /7 days.

            125 hours- In one Month/30days.

            270 hours- In 90 days

          1000 hours – In one year.

If a pilot has performed duty on a flight from 0000 to 0500 LMT he can not perform flight duties the next day from 0000 to 0500 LMT.

Angle of Incidence – Angle of incidence is on acute angle between the longitudinal axis of the airplane and the chord of the wing.

Angle of attack – Angle of attack is an acute angle between the chord of the aerofoil and the relative wind.

–           A high aspect ratio wing –

1. Stalls at lower angle of attack.
2. Less induced drag.
3. Less wing tip vortices.
4. Increased lift

–           It is the ratio between the total air load imposed on the airplane and the pull of the gravity (All up wt.)

–           It is expressed in terms of ‘g’.

            It is also known as acceleration factor/error.

–           Center of pressure is the point on the chord at which the aerodynamic forces are considered to be concentrated.

–           It is a point on the chord at which max lift is achieved.

–           Burble point is the angle of attack at which the streamline flow about a body begins to breakdown.

–           If the angle of attack is increased beyond the burble point the C.P. remains in the same position or moves back slightly.

In a Cambered aerofoil-

            As angle of attack increases, C.P. moves forward.

            As angle of attack decreases, C.P. moves rearward.

In a flat plate-

            As angle of attack increases, C.P. moves rearward.

            As angle of attack decreases, C.P. moves forward.

–           Induced drag decreases as square of speed.

–           Profile drag and parasite drag increases as square of speed.

–           Profile Drag = Skin friction + Form Drag.

–           Parasite drag is due to main parts of a/c joined together.

–           It can be decreased by providing fairing.

In flight if velocity is doubled the lift will increase by square root- 3-4 times.

–           Mean Chord line is an arbitrary line.

–           M.C.L. is straight line on Symmetrical wings.

–           M.C.L. is a chord line on Symmetrical aerofoil. Chord line is always a straight line but M.C.L. is a curved line.

In other words M.C.L. is a line that cuts the aerofoil into two equal parts (Equidistance). Therefore, we can say M.C.L. is a camber line on an Asymmetrical aerofoil.

–           Empennage – Tail plane of the a/c.

–           Low pour point is the temperature at which fluid will ignite.

–           Anti-Icing – Not allowing ice to form.

–           De –Icing – Removal of ice after it has formed.

–           Weight increasing or decreasing will have no affect on gliding angle. If best Lift/Drag ratio speed is maintained for that weight.

–           If weight increases best L/D ratio speed also increases.

            If weight changes L/D ratio also changes.

–           Angle of climb is governed by power (Power = Thrust x Dist)

–           Rate of climb is governed by thrust (Or Excess Thrust)

–           Long Dihedral- Different of angle of incidence of tail plane and main plane.

Neutral point – Neutral point is that position of C.G at which stability is neutral.

For stability C.G has to be ahead of the neutral point.

Dist between C.G and neutral point is called static point/static margin. Therefore, static margin increases C.G. goes forward stability increases. If stability increases, controllability decreases.

–           Clearance Volume – Area when piston is at TOP DEAD CENTRE

–           Swept Volume – Volume/ Area between TOP DEAD CENTRE and BOTTOM DEAD CENTRE

–           Total Volume – Piston at BOTTOM DEAD CENTRE (Swept volume and clearance Volume)

P – Mean effective pressure lbs²/inches.

L – Length of stroke in feet (TOP DEAD CENTRE to BOTTOM DEAD CENTRE in feet)

A – Area of cross –section of cylinder in square inches.

N – No. of Power strokes per minute.

K – No. of cylinder in engine.

I.H.P. = B.H.P + F.H.P.

Brake H.P. is available at propeller/power shaft.

For every 1 power stroke crankshaft rotates twice.

Piston engine is a constant volume cycle.

Because ignition takes place at constant volume.

Jet Engine is a Constant Pressure Cycle.

Because in a Jet Engine for a given Throttle settings, the ignition takes place at a constant pressure.

Temperature and pressure decreases during power stroke.

Exhaust valves are hollow and are filled with sodium for quicker cooling.

Valve Stem/ Tappet Clearance is to allow the value stem expansion due to the change in the temperature.

Volumetric Efficiency is the ratio between the weight of fuel/air mix drawn inside the engine to the weight of fuel/air mix that would have been drawn inside the engine under the standard conditions of temperature and pressure theoretically.

–           Using lean mix with high MAP leads to Detonation.

–           Critical Altitude – Altitude at which super charger can maintain its sea level retch horsepower.

–           Trim Drag – Trim drag is drag produced by trimmers and flying controls when they are deflected into airstreams.

–           Temperature decreases fuel density increases, fuel contracts volume decreases.

–           Temperature increases fuel density decreasing fuel expands volume increases.

–           Climb gradient is worked by TAS and Rate of Climb.

–           Flight path gradient is worked by ground speed and Rate of Climb.

–           Wind velocity affects Flight Path gradient.

–           Head wind increases Flight Path gradient.

–           Tail wind decreases Flight Path gradient.

–           Wind velocity does not affect Rate of Climb, only Angle of climb is affected.

–           If Rate of Climb decreases or increases Angle of climb also changes.

–           But if Angle of climb changes Rate of Climb may or may not changes.

–           Density altitude is altitude corrected for temperature errors.

–           If temperature increases (lapse rate less than 1.98° C/1000 ft) Density altitude is higher than Pressure Altitude.

–           If temperature decreases (lapse rate more than 1.98° C/1000 ft) Density altitude is lower the Pressure Altitude.

In I.S.A. conditions temperature Density Altitude = Pressure Altitude.

–           Angle of climb is governed by Excess thrust.

–           ROC is governed by excess power.

–           Velocity of min power (Vmp) is slightly less than velocity of min drag. (Vmd).

–           When alternate static source is used in most of the un pressurized A/c the pressure is low therefore alt over reads.

–           Fire

            A  –      Wood /Paper.

            B  –      Liquid fire.

            C  –      Electrical.

            D  –      Fire due to metal burning.

–           Earth complete one revolution in 23’56’ minutes- Sidereal Day = 23’56’ (Actual Sun visible)

–           Earth goes around the Sun.

–           Moon goes around the Earth.

–           Moon takes around 29.5 days to go around the Earth.

–           Geo-Stationary – Appears stationary from the Earth.

            Geo- stationary is stationary with reference to a point on the Earth.

–           Waxing Moon increases in size.

            Waning Moon decreases in size.

–           Moon has 4 cycles (4 quarters)

–           These 4 cycles take 21 days.

–           In 1 and 2 cycles Moon is waxing, increases in size.

            In 3 and 4 cycles Moon is waning, decreases in size.

–           Velocity of earth is not constant.

–           It is fastest when Earth is closest to Sun.

            It is slowest when Earth is farthest from Sun.

4^th Jan’ Perihelion – Point where Earth is closest to the Sun.

4^th July Aphelion – Point where Earth is farthest from the Sun.

Perigee – Point where Sun is closest to the Earth.

Apogee – Point where Sun is farthest from the Earth.

Perigee and Apogee are used when considering orbit of Sun around the Earth.

These laws perihelion, aphelion, perigee and apogee are also known as Kepler’s laws.

Perihelion and Aphelion is used when considering Earth’s orbit around the Sun.

Perihelion (4^th Jan’) – Point where Earth closest to the Sun.

Aphelion (4^th July) – Point where Earth farthest from the Sun.

Perihelion and Aphelion are used for Earth’s orbit around the Sun.

Perigee – Sun closest to the Earth.

Apogee – Sun farthest from the Earth.

Perigee and Apogee are used for Sun’s orbit around the Earth.

Equinox – Days and Nights are equal.

Isogonals  = lines joining places and equal variation.

Agonic = zero variation.

Maximum VARIATION in India is 3° w in Trivandrum.

As we go to higher latitudes value of VARIATION increases therefore we don’t use compass above 75’ North or South.

True North – True North direction of geographical/meridian from a place.

Magnetic North – Direction of Magnetic North by a freely suspended magnet.

Compass North – Direction of Compass North by an A/c compass.

Compass of a/c is affected by magnetic field of the A/c.

Deviation – Angular difference between magnetic and compass North measured in degrees East or West of the Magnet North.

Poles are 2 ends of axis of rotation of Earth.

Dist between meridians is maximum at Equator and is called Departure.

The dist between meridians decreases @ Cosine of latitude.

            Deg x 60 = Distance of long

Departure = Distance of long x Cosine of lat.

Convergency – Angle of inclination between 2 meridians on the Earth.

Convergence – Angle of inclination between 2 meridians on a projection.

Degrees  x 60  = Distance of longitude.

            C = Distance of longitude x Sine Mean latitude.

Conversion Angle – Conversion angle is angular difference between the direction of Rhumb line and great circle between 2 places.

            CA = ½ Distance of longitude x Sine Mean latitude.

–           All parallel of latitudes are Rhumb lines.

N.M. is length of an arc, which subtends an angle of one minute at the centre of the Earth.

Length of nm is not constant it is bigger at poles and is smaller at the equator.

            At Equator – one nm is 6048 feet.

            At Poles – one nm is 6107 feet.

            Therefore, average length at 47’30’ N is taken as 6080 feet.

N.M. as per ICAO specification is a measure of 1852 meters.

N.M. is used in flying because it is easier to convert dist in nm in terms of latitude/longitude and vice versa.

–           Cardinal Points are – N, S, E, W.

–           At equator Sun is overhead twice a year.

–           Earth’s rotation about its own axis gives rise to Day and night.

–           Sidereal Day – Sidereal day is measured with reference to fixed point in the space (1^stpoint of Aries.)

–           Civil year has 365 days.

Every 4^th year is a leap year but every 100^th year is not a leap year. (Because duration is less than 365¼ days.)

RELIEFS

–           Spot height – shows exact location of the hill.

–           Layer tinting – higher places are shown by darker colors.

–           Hachures – tilted lines pointing towards high features.

–           Hill Shading – A part of the map is shaded off, light is presumed to come from one side and the area next to the hill is shaded (shadow).

–           Contours – Contours are lines joining places of equal elev. Contours are always numbered towards the higher side when contours are close together, the hill is steep, and when contours are far the hill is shallow.

–           Form lines are dotted/broken contours, they don’t give exact elevation of hill, but they will give shape of the hill. (Places where exact survey cannot be done)

–           In VOR/DME – If ID has ‘Z’ in Id. Code. It means either they are –co-located or are with in 7 nm. and are treated as co-located.

–           If ILS has Id code ‘SCZ’.

First two letters ‘SC’ are of outer markers beacon and second two letters ‘CZ’ are middle markers beacon. Inner marker does not have an Id-code because a/c is at a very less distance from the runway (approx 250-1500 feet)

–           In AWR

            Increased severity is shown by –

1. Black – Clear
2. Green – Light Precipitation
3. Yellow – Medium Precipitation
4. Red – High Precipitation
5. Magenta – Strongest echo for processor.

            PRP = Pulse Recurrence Period

            PRF = Pulse Recurrence Frequency

            Squall – is wind speed above 25 knots.

            Gale – is wind speed above 33 knots.

            Jet Stream – is wind speed above 60 knots

           Hurricane – is wind speed above 63 knots.

Convection – vertical movement of air/atmosphere.

Advection – horizontal movement of air/atmosphere.

Adiabatic Cooling – As the air raises it expands, the expansion of air causes it to cool therefore when air expands the temperature decreases because of decreased molecular density.

Air when sinks, compresses and its temperature increases as it sinks.

Rime Ice – A/c passes super cooled water droplet and icing forms, with air trapped in it Opaque color. It is easy to distinguish and not very dangerous.

Glazed Ice – A/c passes through area of super cooled freezing rain, and forms on a/c as a transparent ice. It is most dangerous type of icing. It also forms on places where de-icing is not possible.

Hoar Frost – A/c parked at night, the ice forms over it. This type of ice should be removed before T/o.

–           Isobar = Equal barometric pressure.

–           Isobars are drawn at 2 hp Intervals in India at low latitudes.

–           At high latitudes Isobars are drawn at 4 hp intervals.

Coriolis force is due to the rotation of the Earth.

It is effect is to deflect moving bodies to the right of their track in N/H. It deflects moving bodies to left of their track in S/H.

Its effect is 0 at Equator and is max at poles.

Isothermal layer (Inversion) is a stable layer.

Sigmet is issued at 01, 00 GMT and is issued every 3 hours.

Sigmet is valid for 4 hours.

TTLF – Trend Type Landing Forecast consists of –

1. Metar (Meteorological Aviation weather report)
2. Trend Forecast.

–           Trend Type Landing Forecast is valid for 2 hours.

–           CAT – Clear Air Turbulence is associated with marked wind shear.

–           CAT visually occurs in jet streams and mountain waves.

–           Jet Stream is above 60 knots and is usually found above 30,000 feets.

–           Virgo – A curtain of precipitation descending from the cumuliform cloud base.

Cirrus fall streaks/mare’s trails/cirrus uncinus – are ice-crystals that descend from cirrus clouds.

–           Polar westerly Jet streams occur 60° N/S – wind speed 80-100 knots.

–           Sub-tropical westerly jets occur 35° N/S – wind speed 100-120 knots.

–           Easterly jets occur South of 10° North – wind speed 80-100 knots.

For Thunderstorm

–           Adequate moisture

–           Steep lapse Rate.

–           Trigger Action (winds ascent/ air rises up)

Orographic Effect – Parcel of air rises when the instability occurs (ELR is more than DALR 3° c/1000feet and SALR 1.5°c/1000feet)

The wind blows against the hill rises and cools down and condensation occurs.

Stages

1. Formation – Only up draft up to 6000feet/minute.

            Man intensity in the middle of the cloud.

2. Mature Stage – Up draft and down draft up to 2400feet/minute.

            Rain starts in the mature stage.

            Up draft produces hailstorm

            Down draft produces squalls.

Max turbulence is encountered in mature stage because a/c experiences up draft and down draft.

            Upper part of CB has Negative charge.

            Lower part of CB has Positive charge.

Thunderstorm– remains in its mature stage for about 30-45 minutes.

Dissipating Stage – has only down drafts.

–           Atmosphere Conditionally Stable – When ELR lies between DALR (3°c/1000feet) and SALR (1.5°c/1000feet)

            Therefore, it is stable for dry air and unstable for saturated air.

–           If ELR is below DALR and SALR, atmosphere is stable for both dry and saturated air.

–           Three types of Jet streams.

1. Poles westerly jet stream at 60° N/S – 80-100 knots.
2. Sub-topical jet stream at 35° N/S – 100-120 knots.
3. Easterly jet stream South of 10° North – 80-100 knots.

–           Coriolis force is due to the rotation of the Earth. It deflects the moving bodies to right of track in N/H.

–           RVR is issued when Visibility falls below 1500 meters.

–           Lateral Separation

VOR – 15° at 15 n.m.

NDB – 30°at 15 n.m.

Dead Reckoning 45° at 15 nm

Radar 5 n.m.

Dme 10 n.m.

Incubation period.

Small Pox/Typhus     14 days.

Relapsing Fever        8 days.

Yellow fever/Plague 6 days.

Cholera                      5 days.

Position report is required

IFR – Every half on hour.

VFR – Every one hour.

Difference between Maps and charts.

Maps – Maps have geographical information and give the widest details of elevation etc.

Charts – Charts are made for a specific purpose. En route charts, Approach charts, Departure etc.

Charts give the least information of geographical features and give the obstacle clearance of a/c in terms of MEA etc and that is also given with in a radius of navigational-aid or a specified point.

–           RVR is measured at 16 feet.

In NOS chart only – In minimum section of approach chart indicator T/o minimums are not standard and IFR departures-procedures are published.

Class ‘A’ airspace begins at 18,000 foots, therefore it is not shown on low altitude en route charts.

Alt airways at 18,000 feet MSL and above are Jet Routes.

ATC should be advised any time airspeed changes by 5% or 10 knots, whichever is greater or if ETA changes above 3 minutes.

You should also inform ATC if your DME fails.

(R) mean Radar service is available and a Radar vectoring can be expected.

Example- MEMPHIS CENTRE (R) – Facility is equipped with radar and a radar vectoring can be expected.

MCA – 7000 N you must be at a ht of 7000 foot if flying in direction of North (N)

Example- MCA V-344 7000E While flying on V344 airway, A/c should be at a Minimum Height of 7000ft if flying in East (E) direction.

TCH 54’ Threshold crossing height is 54’ feet above r/w if you remain on the centerline of glide slope.

–           54’ feet height is above the runway

V – Visual descent pt represents the point from which you can make a normal descent to an landing.

Assuming you have runway in sight and you are at MDA. A descent from the MDA should not be started prior/before reaching the VDP.

V – VDP is point from when a visual approach can be made using a constant descent rate.

A “V” is given at airfields with surrounding high terrain features, since it is a normal tendency to undershoot the approach when flying visual.

–           RVR 24 or ½ means –

–           RVR 2400fts or Visibility ½ statute miles.

–           CTAF – Common Traffic Advisory Frequency.

Airport reference point – ARP is the approximate geometric center of all usable runway surfaces, and is where the official latitude and longitude co-ordinates are desired.

Location and Elevation of airport’s control tower.

HIRL – This note (1) indicator that when key tower is closed pilot controlled lighting can be activated by clicking on VHF set on given VHF frequencies.

–           VOR DME-A – An approach procedure in which the final approach course is more than 30’ from alignment with the runway can be identified by a letter following the primary approach navigational-aid, such as VOR DME –A.

Since on VOR DME-A type runways where a final approach course is not aligned within the 30’ of the r/w only circling minimums are published for this approach procedure.

MVA (Minimum Vectoring Altitude) gives obstacle clearance of 1000’ foot above plain and 2000’ foot above mountainous areas.

MVA also provides a margin of 300 feet above the floor of controlled air space.

-Runway Width                                  Stripes

            18m                                        4

            23m                                        6

            30m                                        8

            45m                                        12

            60m                                        16

–           If an early missed approach is initiated before reaching the MAP, you should proceed to the MAP at or above MDA or DH before executing a turn maneuver.

–           Transmissometer measures (RVR) Running Visual Range.

–           Weather Phenomena Codes.

            Precipitation

            RA – RAIN

            DZ – Drizzle

            SN – Snow

            IC – Ice crystals

            GR – Hail

            GS – Small Hail/Snow pellets

            SG – Snow Grains

            PL – Ice Pellets.

            Obstruction to visibility

            FG – Fog

            BR – Mist

            FU – Smoke

            HZ – Haze

            PY – Spray

            DU – Dust

            VA – Volcanic Ash.

            Other weather Phenomena

            Sq – Squall

            DS – Dust Strom

            FC – Funnel Cloud/Tornadoes/water spout

            SS – Sand Storm

            PO – Dust /Sand whirls.

VNO – Maximum Structural cruising speed

NOTAM

1. By means of telecommunication.
2. By means other than telecommunication.

            A         More than 2 hours.

            B         Less than 2 hours.

            C         Domestic operator.

            D         Defense.

G – Information of more than one FIR, issued from Delhi only.

NOTOM

            N – New

            C – Cancel

            R – Replacing

–           When ROC changes Angle of climb also changes.

–           When Angle of climb change ROC may or may not change.

–           Value of nm is less at equator as compared to poles. Because diameter of Equator is more than the diameter of poles.

–           Servo Altimeter – Digital altimeter.

–           Principle of VOR – Phase comparison.

Simulator Parallel LIS approach can be made if dist between r/w centerline is more than 4300 feet.

–           R/L is a straight line on Mercator.

–           G/c is a straight line on polar Gnomonic.

–           Lamberts chart G/c can be assumed to be a straight line.

–           Any straight line on Mercator is a R/L.

–           Co-efficient A is due to incorrect mounting of Lubber line.

–           Co-efficient B and C can be neutralised by setting up a local magnetic field.

This can be done by a micro adjuster that is placed under compass. (Directly beneath the Compass.)

–           PNR is max in nil wind only.

–           W/v has little effect on PNR.

–           With head wind or tail wind PNR is slightly less.

–           C.P. and PNR are co-located when FOB is just sufficient for flight.

–           PNR can never be before C.P.

            In this case you don’t have sufficient fuel for flight.

–           PNR can be between C.P. and destination.

Acceleration and turning errors are due to vertical (Z) component of the Earth.

TAS = RAS + (1.75% of RAS per 1000 foot)

Servo altimeter has no time lag.

Real Wander – due to gyro wear, Turbulence etc.

Apparent Wander – due to the movement of the Earth, and A/c movement over the Earth.

ADF has null point.

ADF has null seeking equipment

Holding below FL 140 is 1 minute.

Holding above FL 140 is 1.5 minute. (1½ min.)

AGNIS – Azimuth guidance Nose In stand.

PAPA – Parallax Aircraft Parking Aid.

APR is geometric centre of aerodrome.

Carriage of dangerous goods – 2 years imprisonment.

Aerial work A/c – Industrial and commercial purpose but excluding public transport.

Aeroplane – Power driven heavier than air aircraft.

Air ship – Power driven lighter than air aircraft.

Cat B a/c cannot be used for –

1. Aerial work a/c.
2. Public transport a/c.

–           Prohibited Areas-

1. 1 nm from power of silence (Malabar hills)
2. Rashtrapati Bhawan
3. Co-ordinator of gun factory at Baroda.
4. Mathura refinery
5. P.M. house.

–           Petroleum in bulk is more than 900 liters in a Receptacle.

Refueling should be down outdoor and at least 15 meters from any building.

While refueling no naked flame or spark should be allowed with in 30 meters of A/c refueling equipment.

Danger zone – is area with in largest polygon obtainable by joining points 3 meters away from wing and refueling vehicle.

Therefore ground power units air-conditioning units etc should be kept away from Danger zone.

No person other than authorized staff of fueling and police shall be allowed within 15 meters of A/c.

Rear jet outlets should not be with in 43 meters of fuelling equip as a/c.

A/c should not be refueled with in 33 meters of radar.

Flight Navigator is required for flights above 600 nm.

Notification of Accident – 24 hours.

Notification of Incident – 48 hours.

Overtaking – Approaching another a/c from an angle of less than 70’.

Pre-Monsoon/summer – March to May      Hot weather)

Monsoon – June to September

Post Monsoon – October to November

Winter – December to February.

(In India) – At low latitudes isobars are drawn at 2 hp Intervals.

At higher latitudes isobars are drawn at 4 hp Intervals.

A depression is indicated by 2 Isobars.

A cyclone is shown by 4 Isobars.

ITCI – Inter Tropical Convergence Zone – divides equatorial air mass of N.H. and S.H.

This particular line moves towards N and S depending upon summer and winter season.

Trade winds are from equator to 30’ N/S.

Jet Streams are speed above 60 knots and usually found above 30,000foots.

1. Poles westerly jet stream 60° N/S 80-100 knots.
2. Sub tropical jet stream 30°N/S 100-120 knots.
3. Easterly jet streams South of 10°N 80-100 knots.

TAF – Terminal Aerodrome forecast.

ROFOR – Route Forecast.

CWOR – Current weather report.

CWO – Current weather observation.

WWW – World weather watch.

WMO – World Meteorological Organization.

RVR – Runway visual range is issued when Visibility falls below 1500 meters.

CAT – Clear Air Turbulence

RAREP – Radar Report.

INSAT – Indian Satellite

MOR – Met Optical Range.

STJ – Sub Tropical Jet Stream.

PJ – Polar Jet Stream.

TJ – Tropical jet stream.

TEJ – Tropical Easterly jet stream

ROBEX – Regional Operating Meteorological Bulletin Exchange.

Isobar = Equal pressure

Isotherm = Equal temperature.

Isohygric = Equal humidity.

Isopycric = Equal Air density.

Isohytes = Equal Rain fall.

Isogone = Equal wind direction

Isotach = Equal wind speed.

Isollabar = Equal pressure change.

Isohypsis = Equal ht on constant pressure charts.

Isochrones = same time of occurrence of some Phenomena.

Isopores = Annual change in variation

Isoclinal = Equal Dip.

Aclinic = Zero Dip.

Isogonic = Equal variation

Agonic = Zero variation.

Isochemical = Lines of equal mean temperature in Winter.

Isotheral = Lines of equal mean temperature on Summer.

Isopleth = Lines joining places of some data of some value.

Thermal winds are parallel to Isotherms.

Max concentration of ozone layer occurs between 15 km to 25 km

Moist air is lighter than dry air.

Jet streams are extreme cases of thermal winds.

Proro – is route forecast with height indication in pressure units.

Ceilometers are used to measure ht of base of cloud.

Roaring Forties are strong westerly winds that blows over regions between 40’ S to 50’ S.

ROBEX – Regional Observatory Meteorological.Bulletin Exchange.

Diurnal Variation of pressure has

–           Two minimums   4 A.M and 4 P.M.

–           Two Maximums 10 A.M and 10 P.M.

Land and Sea breezes are due to diurnal variation of the temperature.

ATIS – Automatic Terminal Information Service on VHF.

SIGMET – Significant Meteorological Weather Report.

PANS – Procedure for Air Navigation.

Volmet – is met broadcast on HF from BB and CC every half on hour.

            Validity of-

–           TAF 12 hours issued every 9 hours.

–           SIGMET 4 hours issued every 3 hours.

–           TREND FORECAST – 2 hours.

–           VA is design-maneuvering speed.

 Density of air is low at equatorial region than the Polar region because of high temperature and low pressure at equator.

Barometer/Barograph – measure Pressure.

Thermometer/ Thermograph – measures Temperature.

Psychrometer – measures humidity.

Hygrograph – measures Relative humidity.

Rain gauge – measures Rainfall.

Aero vane Transmitter – measures wind direction and speed.

Wind Vane – measures wind direction only.

Anemometer –measure wind speed in Knots.

Ceilometers/clinometers – measures Cloud base in Meters.

Alidade Apparatus/Radar observation –measures cloud base in meters.

Radio Sonde –measures upper air temperature and humidity

                        (Measurement through released balloon)

Ravin Sonde –measures upper air data of winds.

                        (Direction and speed)

Transmissometer/Scopograph –measures Visibility in meters/kms, and are also used to measure RVR when Visibility falls below 1500 meters.

Richardson’s scale – measures CAT intensity.

Hydrometer –measures specific gravity.

QGH – Let down procedure using VHF/DF.

QFE – Altitude setting to show vertical separation above airfield elevation.

Classes of CAT Clear Air Turbulence.

Class I – Caused by vertical and horizontal wind shear.

Class II – Caused by Mountain waves.

Class III – Caused by Convection currents.

Class IV – Caused by trough turbulence or frontal disturbances.

C.A.T. is more severe in East-West directions.

During Oct to May Northern and Central India experiences clear Air turbulence.

–           Types of clouds

            High clouds – 20,000feet and above.

            Medium clouds – 8,000 feet – 20,000 feet.

            Low clouds –below 8,000feet.

–           Frontogenesis are – Formation of a front.

–           Frontolysis are – Dissipation of a front.

–           Willy-Willy – A typical cyclone of hurricane strength (63 knots) near Australia.

TCAS

–           A/c having seating capacity of 30 passengers or payload capacity of 3 tons should have TCAS-II.

–           A/c having seating capacity of 20-30 passengers OR Maximum certified T/o mass in excess of 5700 kgs., should have TCAS –II.

–           A/c having seating capacity of 10-19 passengers OR Maximum certified T/o mass below 5700 kgs.,- TCAS – I.

–           Twinjets having seating capacity of less than 10 passengers OR Man T/o mass below 5700 kgs. – TCAS –I.

–           In India there are four International Notam Offices.

1. Delhi
2. Kolkatta
3. Mumbai
4. Chennai

–           All arriving A/c at or below 10,000 ft with in 30 nm of radius of VOR/DME.

            30 –15 nm – IAS not more than 250 knots.

            Below 15 nm– IAS not more than 210 knots.

–           Final – less than 4 nm from Approach end of Runway.

–           Long Final – 8 nm from Approach end of Runway.

–           A/c having max T/o mass above 1,36,000 kg, shall include “Heavy” after call sign in its Initial R/T contact.

–           FDTL – from the time of reporting at the airport with the termination of flight or a series of flights (CHOKES ON + 15 minutes)

–           Flight time – From the time the a/c starts taxying under its own power for T/o till it comes to rest at the end of flights.

–           FDTL is applicable to all flight crew personnel

            1000 hours – 12 months

            270 hours- 90 days

           125 hours – 30 days

             30 hours – 7 days

             8 hours – 24 hours.

            A rest period of 16 hours shall be given in 24 hours.

–           Each flight crew shall be relieved from all duty for at least 24 hours in any 7 consecutive days.

–           Flight crew shall not undertake any duty between 0000 to 0500 hours local time, if previous day he performed flight duty between 0000 to 0500 hours local time.

–           Total number of landings allowed – 6 landings

This shall not include landings for training flight, technical reasons or diversions.

–           A/c above 5700 kg minimum crew required – 2 Pilots.