Emergency procedures

Question 1

ENGINE FAILURE DURING FLIGHT (Restart Procedures)

Answer 1

ENGINE FAILURE DURING FLIGHT (Restart Procedures)
1. Airspeed -68 KIAS (best glide speed)
2. FUEL SHUTOFF Valve - ON (push full in)
3. FUEL SELECTOR Valve - BOTH
4. FUEL PUMP Switch - ON
5. Mixture Control - RICH (if restart has not occurred)
6. MAGNETOS Switch - BOTH (or START if propeller is stopped)

Question 2

ENGINE FAILURE DURING TAKEOFF ROLL

Answer 2

ENGINE FAILURE DURING TAKEOFF ROLL
1. Throttle Control - IDLE (pull full out)
2. Brakes - APPLY
3. Wing Flaps - RETRACT
4. Mixture Control - IDLE CUTOFF (pull full out)
5. MAGNETOS Switch - OFF
6. STBY BATT Switch - OFF
7. MASTER Switch (ALT and BAT) - OFF

Question 3

ENGINE FAILURE IMMEDIATELY AFTER TAKEOFF

Answer 3

ENGINE FAILURE IMMEDIATELY AFTER TAKEOFF
1. Airspeed -70 KIAS - Flaps UP
65 KIAS - Flaps 10° - FULL
2. Mixture Control - IDLE CUTOFF (pull full out)
3. FUEL SHUTOFF Valve - OFF (pull full out)
4. MAGNETOS Switch - OFF
5. Wing Flaps - AS REQUIRED (FULL recommended)
6. STBY BATT Switch - OFF
7. MASTER Switch (ALT and BAT) - OFF
8. Cabin Door - UNLATCH
9. Land - STRAIGHT AHEAD

Question 4

EMERGENCY LANDING WITHOUT ENGINE POWER

Answer 4

EMERGENCY LANDING WITHOUT ENGINE POWER
1. Pilot and Passenger Seat Backs - MOST UPRIGHT POSITION
2. Seats and Seat Belts - SECURE
3. Airspeed -70 KIAS - Flaps UP
65 KIAS - Flaps 10° - FULL
4. Mixture Control - IDLE CUTOFF (pull full out)
5. FUEL SHUTOFF Valve - OFF (pull full out)
6. MAGNETOS Switch - OFF
7. Wing Flaps - AS REQUIRED (FULL recommended)
8. STBY BATT Switch - OFF
9. MASTER Switch (ALT and BAT) - OFF (when landing is
assured)
10. Doors - UNLATCH PRIOR TO TOUCHDOWN
11. Touchdown - SLIGHTLY TAIL LOW
12. Brakes - APPLY HEAVILY

Question 5

FIRES
DURING START ON GROUND

Answer 5

FIRES
DURING START ON GROUND
1. MAGNETOS Switch - START (continue cranking to start the
engine)
IF ENGINE STARTS
2. Power - 1800 RPM (for a few minutes)
3. Engine - SHUTDOWN (inspect for damage)
IF ENGINE FAILS TO START
2. Throttle Control - FULL (push full in)
3. Mixture Control - IDLE CUTOFF (pull full out)
4. MAGNETOS Switch - START (continue cranking)
5. FUEL SHUTOFF Valve - OFF (pull full out)
6. FUEL PUMP Switch - OFF
7. MAGNETOS Switch - OFF
8. STBY BATT Switch - OFF
9. MASTER Switch (ALT and BAT) - OFF

Question 6

What should the pilot do if encountering INADVERTENT ICING ENCOUNTER DURING FLIGHT?

Answer 6

ICING
INADVERTENT ICING ENCOUNTER DURING FLIGHT
1. PITOT HEAT Switch - ON
2. Turn back or change altitude (to obtain an outside air temperature that is less conducive to icing)
3. CABIN HT Control Knob - ON (pull full out)
4. Defroster Control Outlets - OPEN (to obtain maximum windshield defroster airflow)
5. CABIN AIR Control Knob - ADJUST (to obtain maximum defroster heat and airflow)
6. Watch for signs of induction air filter icing. A loss of engine RPM could be caused by ice blocking the air intake filter. Adjust the throttle as necessary to hold engine RPM. Adjust mixture as necessary for any change in power settings.
7. Plan a landing at the nearest airport. With an extremely rapid ice build-up, select a suitable off airport landing site.
8. With an ice accumulation of 0.25 inch or more on the wing leading edges, be prepared for significantly higher power requirements, higher approach and stall speeds, and a longer landing roll.
9. Leave wing flaps retracted. With a severe ice build-up on the horizontal tail, the change in wing wake airflow direction caused by wing flap extension could result in a loss of elevator effectiveness.
10. Open left window and, if practical, scrape ice from a portion of the windshield for visibility in the landing approach.
11. Perform a landing approach using a forward slip, if necessary, for improved visibility.
12. Approach at 65 to 75 KIAS depending upon the amount of ice accumulation.
13. Perform landing in level attitude.
14. Missed approaches should be avoided.

Question 7

What should the pilot do if she suspects STATIC SOURCE BLOCKAGE
(ERRONEOUS INSTRUMENT READING SUSPECTED) ?

Answer 7

STATIC SOURCE BLOCKAGE
(ERRONEOUS INSTRUMENT READING SUSPECTED)
1. ALT STATIC AIR Valve - ON (pull full out)
2. Cabin Vents - CLOSED
3. CABIN HT and CABIN AIR Control Knobs - ON (pull full out)
4. Airspeed - Refer to Section 5, Figure 5-1 (Sheet 2) A

Question 8

What should the pilot do if she suspects EXCESSIVE FUEL VAPOR?

Answer 8

EXCESSIVE FUEL VAPOR
FUEL FLOW STABILIZATION PROCEDURES
(If flow fluctuations of 1 GPH or more, or power surges occur.)
1. FUEL PUMP Switch - ON
2. Mixture Control - ADJUST (as necessary for smooth engine operation)
3. Fuel Selector Valve - SELECT OPPOSITE TANK (if vapor symptoms continue)
4. FUEL PUMP Switch - OFF (after fuel flow has stabilized)

Question 9

What is a spin?

Answer 9

A spin in a small airplane or glider is a controlled (recoverable) or uncontrolled (possibly unrecoverable) maneuver in which the airplane or glider descends in a helical path while flying at an angle of attack (AOA) greater than the critical AOA. Spins result from aggravated stalls in either a slip or a skid. If a stall does not occur, a spin cannot occur. In a stall, one wing will often drop before the other and the nose will yaw in the direction of the low wing.

Question 10

Describe several flight situations where an unintentional spin may occur.

Answer 10

A stall/spin situation can occur in any phase of flight but is most likely to occur in the following situations:

a. Engine failure on takeoff during climb out - pilot tries to stretch glide into landing area by increasing back pressure or makes an uncoordinated turn back to departure runway a a relatively low airspeed.

b. Cross-controlled turn from base to final (slipping or skidding turn) - pilot overshoots final (possibly due to a crosswind) and makes an uncoordinated turn at a low airspeed.

c. Engine failure on approach to landing - pilot tries to stretch glide to the runway by increasing back pressure.

d. Go-around with excessive nose-up trim - pilot applies power with full flaps and nose-up trim combined with uncoordinated use of rudder.

e. Go-around with improper flap retraction - pilot applies power and retracts flaps rapidly resulting in a rapid sink rate followed by an instinctive increase in back pressure.

Question 11

What is the recommended procedure for recovery from a spin?

Answer 11

Should an inadvertent spin occur, the following recovery procedure
should be used:
1. RETARD THROTTLE TO IDLE POSITION.
2. PLACE AILERONS IN NEUTRAL POSITION.
3. APPLY AND HOLD FULL RUDDER OPPOSITE TO THE DIRECTION OF ROTATION.
4. JUST AFTER THE RUDDER REACHES THE STOP, MOVE THE CONTROL WHEEL BRISKLY FORWARD FAR ENOUGH TO BREAK THE STALL. Full down elevator may be required at aft center of gravity loadings to assure optimum recoveries.
5. HOLD THESE CONTROL INPUTS UNTIL ROTATION STOPS.
Premature relaxation of the control inputs may extend the
recovery.
6. AS ROTATION STOPS, NEUTRALIZE RUDDER, AND MAKE A SMOOTH RECOVERY FROM THE RESULTING DIVE.

NOTE:
If the rate of the spin makes determining the direction of rotation difficult, the magenta turn rate indicator at the top of the HSI compass card will show the rate and direction of the turn. The HSI compass card will rotate in the opposite direction. Hold opposite rudder to the turn vector direction.

Question 12

What does an aft center of gravity do to an aircraft’s spin characteristics?

Answer 12

Recovery from a stall in any aircraft becomes progressively more difficult at its center of gravity moves aft. This is particularly important in spin recovery, as there is a point in rearward loading of any airplane at which a “flat” spin will develop. A “flat” spin is one in which centrifugal force acting through a center of gravity located well to the rear, will pull the tail of the airplane out away from the axis of the spin, making it impossible to get the nose down and recover.

Question 13

What load factor is present in a spin?

Answer 13

The load factor during a spin will vary with the spin characteristics of each airplane but is usually found to be slightly above the 1G load of level flight. There are two reasons this is true:

a. The airspeed in a spin is very low (usually within 2 knots of the unaccelerated stalling speed); and

b. The airplane pivots, rather than turns, while it is in a spin.

Question 14

What procedures should be followed concerning a partial loss of power in flight?

Answer 14

If a partial loss of power occurs, the first priority is to establish and maintain a suitable airspeed (best glide airspeed if necessary),

Then, select an emergency landing area and remain within gliding distance. As time allows, attempt to determine the cause and correct it. Complete the following checklist:

a. Check the carburetor heat.
b. Check the amount of fuel in each tank and switch fuel tanks if necessary.
c. Check the fuel selector valve’s current position.
d. Check the mixture control.
e. Check that the primer control is all the way in and locked.
f. Check the operation of the magnetos in all three positions: both, left or right.

Question 15

In the event of a complete engine failure on takeoff, what procedure is recommended?

Answer 15

a. Retard the throttle to IDLE
b. Apply pressure to BRAKES
c. Retract FLAPS
d. Set the mixture to IDLE CUT OFF
e. Turn the IGNITION to OFF
f. Turn the MASTER OFF

Question 16

If the engine failure occurs immediately after takeoff, what procedure is recommended?

Answer 16

If an engine failure occurs immediately after takeoff, and before a safe maneuvering altitude is attained, it is usually inadvisable to attempt to turn back to the field from which the takeoff was made. Instead, it is generally safer to immediately establish the proper glide attitude, and select a field directly ahead or slightly to either side of the takeoff path.

Complete the checklist:

1. Airspeed -70 KIAS - Flaps UP ;
   65 KIAS - Flaps 10° - FULL
2. Mixture Control - IDLE CUTOFF (pull full out)
3. FUEL SHUTOFF Valve - OFF (pull full out)
4. MAGNETOS Switch - OFF
5. Wing Flaps - AS REQUIRED (FULL recommended)
6. STBY BATT Switch - OFF
7. MASTER Switch (ALT and BAT) - OFF
8. Cabin Door - UNLATCH
9. Land - STRAIGHT AHEAD

Question 17

What is the recommended procedure to be followed for an engine failure while en route?

Answer 17

ENGINE FAILURE DURING FLIGHT (Restart Procedures)
1. Airspeed -68 KIAS (best glide speed)
2. FUEL SHUTOFF Valve - ON (push full in)
3. FUEL SELECTOR Valve - BOTH
4. FUEL PUMP Switch - ON
5. Mixture Control - RICH (if restart has not occurred)
6. MAGNETOS Switch - BOTH (or START if propeller is stopped)

NOTE: If the propeller is windmilling, engine will restart automatically within a few seconds. If propeller has stopped (possible at low speeds), turn MAGNETOS switch to START, advance throttle slowly from idle and lean the mixture from full rich as required to obtain smooth operation.

7. FUEL PUMP Switch - OFF

NOTE: If the indicated fuel flow (FFLOW GPH) immediately drops to zero, a sign of failure of the engine-driven fuel pump, return the FUEL PUMP switch to the ON position.

Question 18

After experiencing an engine failure immediately after takeoff (before reaching safe maneuvering altitude), why is it usually inadvisable to attempt a landing on the runway you have just departed from?

Answer 18

If an engine failure occurs immediately after takeoff, in most cases, the
landing should be planned straight ahead with only small changes in
direction to avoid obstructions. Altitude and airspeed are seldom
sufficient to execute the 180° gliding turn necessary to return to the
runway. The checklist procedures assume that adequate time exists to
secure the fuel and ignition systems prior to touchdown.

Question 19

Explain the approximate altitude loss and factors to consider when maneuvering an airplane that has just taken off, experienced an engine failure at 300 feet AGL and is attempting to turn back to the departure runway.

Answer 19

The turn back to the runway will require approximately 270° (180° to get turned around, 45° to get pointed at the runway, and 45° for final alignment with the runway). Using a standard rate turn of 3° per second, it will take approximately 90 seconds to make the turn. If the airplane descends at approximately 500 fpm, it will have descended approximately 750 feet, placing it 450 feet below the runway.

Other factors to consider:
a. The initial reaction time of 4 seconds and corresponding loss of airspeed and altitude.

b. The downwind turn must be made immediately, which increases the ground speed and rushes the pilot even more in the performance and planning of the procedure.

c. The apparent increase in GS could mislead the pilot into attempting to prematurely slow the airplane down resulting in a possible stall.

d. The pilot will tend to use steeper bank angles than required for a standard rate turn, resulting in an increase in load factor, stall speed and rate of descent.

e. The airplane will lose considerable altitude during the turn and might still be in a bank when the ground is contacted.

Question 20

If an engine failure has occurred while en route and a forced landing is imminent, what procedures should be followed?

Answer 20

a) Establish best glide speed

b) Begin a scan for an appropriate field for landing using the following order of preference:
1) paved airport
2) Unpaved airport
3) paved road with no obstacles
4) Unpaved road with no obstacles
5) Grass field
6) Plowed field
7) Lakes or ponds
8) Trees or other structures

c) Attempt an engine restart

d) Set your transponder to “7700”

e) Transmit a “mayday” message on either the freq in use or 121.5

f) Begin to spiral down over the approach end of the selected landing site.

g) On your final approach complete the forced landing checklist.

Question 21

Immediately before touchdown in a forced landing procedure, what items should be completed?

Answer 21

The Emergency Landing Checklist

EMERGENCY LANDING WITHOUT ENGINE POWER
1. Pilot and Passenger Seat Backs - MOST UPRIGHT POSITION
2. Seats and Seat Belts - SECURE
3. Airspeed -70 KIAS - Flaps UP
65 KIAS - Flaps 10° - FULL
4. Mixture Control - IDLE CUTOFF (pull full out)
5. FUEL SHUTOFF Valve - OFF (pull full out)
6. MAGNETOS Switch - OFF
7. Wing Flaps - AS REQUIRED (FULL recommended)
8. STBY BATE Switch - OFF
9. MASTER Switch (ALT and BAT) - OFF (when landing is assured)
10. Doors - UNLATCH PRIOR TO TOUCHDOWN
11. Touchdown - SLIGHTLY TAIL LOW
12. Brakes - APPLY HEAVILY

Question 22

In an engine failure situation, what glide ratio will be obtained if the best-glide airspeed is maintained?

Answer 22

A loss of 600 feet per 1 nm

Question 23

If an engine failure has occurred while over water, and you are beyond power-off gliding distance to land, what procedures should be followed?

Answer 23

1. Radio - TRANSMIT MAYDAY on 121.5 MHz, (give location, intentions and SQUAWK 7700)
2. Heavy Objects (in baggage area) - SECURE OR JETTISON (if possible)
3. Pilot and Passenger Seat Backs - MOST UPRIGHT POSITION
4. Seats and Seat Belts - SECURE
5. Wing Flaps - 20° - FULL
6. Power - ESTABLISH 300 FT/MIN DESCENT AT 55 KIAS
   NOTE: If no power is available, approach at 70 KIAS with Flaps UP or at 65 KIAS with Flaps 10°.
7. Approach - High Winds, Heavy Seas - INTO THE WIND
   Light Winds, Heavy Swells - PARALLEL TO SWELLS
8. Cabin Doors - UNLATCH
9. Touchdown - LEVEL ATTITUDE AT ESTABLISHED RATE OF DESCENT
10. Face - CUSHION AT TOUCHDOWN (with folded coat)
11. ELT - ACTIVATE
12. Airplane - EVACUATE THROUGH CABIN DOORS

NOTE: If necessary, open window and flood cabin to equalize pressure so doors can be opened.

13. Life Vests and Raft - INFLATE WHEN CLEAR OF AIRPLANE

Question 24

What is detonation?

Answer 24

Detonation is an uncontrolled, explosive ignition of the fuel/air mixture within the cylinder’s combustion chamber. It causes excessive temperatures and pressures which, if not corrected, can quickly lead to failure of the piston, cylinder, or valves. In less severe cases, detonation causes engine overheating, roughness, or loss of power. It is characterized by high cylinder head temperatures, and is most likely to occur when operating at high power settings.

Question 25

What are some of the most common causes of detonation?

Answer 25

a. Using a lower fuel grade than specified by the aircraft manufacturer

b. Operating with extremely high manifold pressures in conjunction with low RPM.

c. Operating the engine at high power settings with an excessively lean mixture.

d. Extended ground operations or steep climbs where cylinder cooling is reduced.

Question 26

What action should be taken if detonation is suspected?

Answer 26

Detonation may be avoided by following these basic guidelines during the various phases of ground and flight operations:

a. Make sure the proper grade of fuel is being used.

b. While on the ground, keep the cowl flaps (if available) in the full-open position.

c. During takeoff and initial climb, use an enriched fuel mixture, as well as a shallower climb angle to increase cylinder cooling.

d. Avoid extended, high power, steep climbs.

e. Develop habit of monitoring engine instruments to verify proper operation.

Question 27

What is preignition?

Answer 27

Preignition occurs when the fuel/air mixture ignites prior to the engine’s normal ignition event.

Premature burning is usually caused by a residual hot spot in the combustion chamber, often created by a small carbon deposit on a spark plug, a cracked spark plug insulator, or other damage in the cylinder that causes a part to heat sufficiently to ignite the fuel/air charge. Preignition causes the engine to lose power, and produces a high operating temperature. As with detonation, preignition may also cause severe engine damage, because the expanding gases exert excessive pressure on the piston while still on its compression stroke.

Question 28

What actions should be taken if preignition is suspected?

Answer 28

Detonation and preignition often occur simultaneously and one may cause the other. Since either condition causes high engine temperature accompanied by a decrease in engine performance, it is often difficult to distinguish between the two. Using the recommended grade of fuel, and operating the engine within its proper temperature, pressure, and RPM ranges, reduces the chance of detonation or preignition.

Question 29

If the engine begins to run rough when flying through heavy rain, what action should be taken?

Answer 29

During flight through heavy rain, it is possible for the induction air filter to become water saturated. The situation will reduce the amount of available air to the carburetor resulting in an excessively rich mixture and a corresponding loss of power. Carburetor heat may be used as an alternate source of air in such a situation.

Question 30

Are there any special considerations necessary when using the auxiliary pump after an engine-driven fuel pump failure?

Answer 30

In a high-wing, single-engine aircraft, which has sustained an engine-driven fuel pump failure, gravity flow will provide sufficient fuel flow for level or descending flight. If the failure occurs while in a climb or the fuel pressure falls below 0.5 PSI, the auxiliary fuel pump should be used.

Question 31

What operating procedure could be used to minimize spark plug fouling?

Answer 31

Always using the recommended lean setting for the given condition.

(Engine roughness may occur due to “fouling” of the spark plug electrodes. This condition may occur on the ground or in the air and is usually the result of an excessively rich mixture setting which causes unburned carbon and lead deposits to collect on the spark plug electrodes.)

Question 32

During a cross-country flight you notice that the oil pressure is low, but the oil temperature is normal. What is the problem and what action should be taken?

Answer 32

Could be:

a. Insufficient oil
b. clogged oil pressure relief valve
c. oil pressure gauge malfunction

In any case, a landing at the nearest airport is advisable to check for the cause of trouble.

Question 33

If a loss of oil pressure occurs accompanied by a rising oil temperature, what is indicated? (POH)

Answer 33

The oil required for cooling has been lost, and an engine failure is imminent. The throttle should be reduced, and a suitable landing area should be established as soon as possible. Use minimum power to reach the emergency landing area.

Question 34

What procedure should be followed if an engine fire develops on the ground during starting? (POH)

Answer 34

Continue to attempt an engine start as a start will cause flames and excess fuel to be sucked back through the carburetor.

a. if the engine starts…increase the power to a higher rpm for a fem moments then shut down and inspect.

b. If the engine does not start…
(1) Set the throttle to the “Full” position.
(2) Set the mixture to “Idle cutoff.”
(3) Continue to try an engine start in an attempt to put out the fire by vacuum.

c. If the fire continues…
(1) obtain fire extinguisher and/or fire personnel assistance.
(2) Turn master off
(3) Turn ignition off
(4) Set fuel selector to off
(5) Extinguish fire
(6) Evacuate

Question 35

What procedure should be followed if an engine fire develops in flight? (POH)

Answer 35

In the event of an engine fire in flight, the following procedure should be used:

a. Set the mixture to “Idle cutoff”
b. Set the fuel selector valve to “OFF”
c. Turn the master switch to “OFF”
d. Set the cabin heat and air fents to “OFF;” leave the overhead vents “ON”
e. establish an airspeed of 105 KIAS and increase the descent, if necessary, to find an airspeed that will provide for an incombustible mixture.

Question 36

What procedure should be followed if an electrical fire develops inside the aircraft? (POH)

Answer 36

If an electrical fire is suspected (burning odor), the pilot should initially try to identify the possible source by checking all circuit breakers, avionics and instruments. If the problem is not detected adn the odor or smoke continues, the following checklist should be completed:

a. Turn the master switch to “OFF”
b. Set the avionics power switch to “OFF”
c. Set all other switches to “OFF” except the ignition switch
d. Close all air/heat vents as well as any other air vents
e. Use fire extinguisher

Question 37

What troubleshooting procedure should be followed in determining the cause of an electrical fire that is not readily apparent? (POH)

Answer 37

If the electrical fire is out and electrical power is necessary for continued flight, the following may be performed:

a. Turn the master switch “ON”
b. Check all the circuit breakers for their status; DO NOT RESET
c. Check that all radio switches are OFF
d. Turn avionics power switch ON
e. Cautiously turn radio and electrical switches ON one at a time with a short delay after each until short circuit is isolated.

Question 38

What procedure should be followed if a cabin fire develops in flight? (POH)

Answer 38

Typically cabin fires are electrical in nature and identifying and disabling the faulty circuit is the first priority. However, careless smoking by passengers has also been a significant cause of cabin fires. The following checklist should be completed:

a. Master - OFF
b. Close all air/heat vents
c. Use a fire extinguisher
d. Land as soon as possible

Question 39

What procedure should be followed if a wing fire develops in flight? (POH)

Answer 39

If a wing fire develops in flight, the following checklist should be completed:

a. Set the navigation light switch to OFF
b. Set the strobe light switch to OFF
c. Set the pitot heat switch to OFF

Initiate a sideslip maneuver to avoid flames from getting the the fuel tank and cabin area, then land as soon as possible.

Question 40

What are the three main types of aircraft icing? (AC00-6A)

Answer 40

Structural, induction system and instrument icing

Question 41

What are the three types of structural ice that may occur in flight? (AC 00-6A)

Answer 41

CLEAR ICE - forms after initial impact when the remaining liquid portion of the drop flows out over the aircraft surface, gradually freezing as smooth sheet of solid ice.

RIME ICE - forms when drops are small, such as those in stratified clouds or light drizzle. The liquid portion remaining after initial impact, freezes rapidly before the drop has time to spread out over the aircraft surface.

MIXED ICE - forms when drops vary in size or when liquid drops are intermingled with snow or ice particles. The ice particles become imbedded in clear ice, building very rough accumulation.

Question 42

What is necessary for structural icing to occur? (AC 00-6A)

Answer 42

The aircraft must be flying through visible water such as rain or cloud droplets; temperature must be at the point where moisture strikes the aircraft at 0°C or colder.

Question 43

What type of structural icing is more dangerous, rime or clear? (AC 00-6A)

Answer 43

Clear ice is hard, heavy and tenacious. It is typically the most hazardous ice encountered. Clear ice forms when after initial impact, the remaining liquid portion of the drop flows out over the aircraft surface, gradually freezing as a smooth sheet of solid ice. This type forms when drops are large, as in rain or in cumuliform clouds. Its removal by deicing equipment is especially difficult due to the fact that it forms as it flows away from the deicing equipment (inflatable boots, etc).

Question 44

During your preflight planning, what type of meteorological information should you be aware of with respect to icing? (AC 91-74)

Answer 44

a. Location of fronts - the fronts location, type, speed and direction of movement.

b. Cloud layers - the location of cloud bases and tops: this is valuable when determining if you will be able to climb above icing layers or descend beneath those layers into warmer air; reference PIREPS and area forecasts.

c. Freezing level(s) - important when determining how to avoid icing and how to exit icing conditions if accidentally encountered.

d. Air temperature and pressure - icing tends to be found in low-pressure areas and at temperatures at or around freezing.

Question 45

What is the definition of the term “freezing level” and how can you determine where that level is? (AC 00-6A)

Answer 45

The freezing level is the lowest altitude in the atmosphere over a given location at which the air temperature reaches 0°C. It is possible to have multiple freezing layers when a temperature inversion occurs above the defined freezing level. A pilot can use current icing products and forecast icing products, as well as the freezing level graphics chart to determine the approximate freezing level. Other potential icing information are:

Area forecasts
PIREPS
AIRMETS
SIGMETS
Surface analysis charts
Low level significant weather charts
Winds and Temperatures aloft (for air temp at altitude)