11.EMERGENCY PROCEDURES
Electrical system malfunctions:
Malfunctions in the electrical power supply system can be detected by periodic monitoring of the ammeter, however, the cause of these malfunctions is usually difficult to determine. A broken alternator drive belt or wiring is the most common cause of alternator failures, although other factors could cause the problem. A damaged or improperly adjusted voltage regulator can also cause malfunctions. All electrical problems of this nature constitute an electrical emergency and should be dealt with immediately. Electrical power malfunctions usually fall into two categories:
After periods of heavy electrical usage (such as starting and taxiing), the battery condition may be low enough to accept above than normal charging during initial flight. However, after 30 minutes of cruising flight, the ammeter should be reading normal. If the charging rate remains above normal on a long flight, it is possible that the battery will overheat. In addition, electronic components could be adversely affected by the higher than normal voltage if a faulty voltage regulator setting is causing the overcharging. To preclude these possibilities, the alternator side of the split Master switch should be turned “OFF”. The flight should be terminated and/or the current drain on the battery minimized as soon as practical because the battery can supply the electrical system for only a limited period of time. If it becomes apparent that the battery voltage is getting too low to operate the electrical system, the alternator switch can be turned on for several minutes at a time until the battery is partially recharged. If the emergency occurs at night, the alternator switch should be returned to the “ON” position just before landing lights will be required for landing.
If the ammeter indicates a continuous discharge rate in flight, the alternator is not supplying power to the system and should be shut down, since the alternator field circuit may be placing an unnecessary load on the system. All non-essential equipment should be turned “OFF” and the flight terminated as soon as practical.
Electric Trim malfunctions:
In the event of an electric trim “runaway” malfunction, immediate corrective measures are required as follows:
Minimize the pitch attitude change of the aircraft by applying opposing pressure on the control stick as required.
Assuming that a trim button is sticking, attempt to release the sticking as soon as possible.
If necessary, trim the electric trim circuit breaker and leave disconnected for the remainder of the flight.
Rough engine operation or Loss of power:
A slight engine roughness in flight may be caused by one or more spark plugs becoming fouled by carbon or lead deposits. This may be verified by turning the ignition switch momentarily from “BOTH” to either “LEFT” or “RIGHT” position. An obvious power loss in single ignition operation is evidence of spark plug or magneto trouble. Assuming that spark plugs are the more likely cause, lean the mixture to the normal lean setting for cruising flight. If the problem does not clear up in several minutes, determine if a richer mixture setting will produce smoother operation. If not, proceed to the nearest airport for repairs using the “BOTH” position of the ignition switch unless extreme roughness dictates the use of a single ignition position.
A sudden engine roughness or misfiring is usually evidence of magneto problems. Switching from “BOTH” to either “LEFT” or “RIGHT” ignition switch position will identify which magneto is malfunctioning. Select different power settings and enrichen mixture to determine if continued operation on “BOTH” magnetos is practical. If not, switch to the good magneto and proceed to the nearest airport for repairs.
Engine driven fuel pump failure
Failure of the engine-driven fuel pump will be evidenced by a sudden reduction in the fuel flow indication prior to a loss of power, while operating from a tank containing adequate fuel.
In the event of a pump failure during take-off, immediately switch on the auxiliary fuel pump switch until the aircraft is well clear of obstacles, after which, maneuver the aircraft for landing.
If low oil pressure is accompanied by normal temperature, there is a possibility that the oil pressure gauge or relief valve is malfunctioning. A leak in the line to the gauge sensor is not necessarily cause for an immediate pre-cautionary landing because an orifice in this line will prevent a sudden loss of oil from the engine sump. However, a landing at the nearest airport would be advisable to inspect source of the trouble.
If a total loss of oil pressure is accompanied by a rise in oil temperature, there is a good reason to suspect an engine failure is imminent. Reduce the engine power immediately and select a suitable forced landing field. Leave the engine running at low power during the approach, using only the minimum power required to reach the desired touch down spot.
Before attempting an “off airport” landing, one should drag the landing area at low altitude to inspect the terrain for obstructions and surface conditions, proceeding as follows:
Drag over the selected field with 1st notch of flaps and 90 mph airspeed, noting the preferred area for touchdown for the next landing approach. Then, retract flaps upon reaching a safe altitude and airspeed.
On downwind leg, turn off all switches except the master and ignition switches.
Approach with flaps at 80 mph
Unlock cabin doors prior to final approach
Before touchdown, turn ignition and master switches “OFF”
Land in slightly tail-low attitude
If an engine stoppage occurs, establish a flaps-up glide at 85 mph. If time permits, attempt to restart the engine by checking for fuel quantities, proper fuel selector valve position and mixture control setting. Also check that the ignition switch is in the correct position. If all attempts to restart the engine fail and a forced landing is imminent, select a suitable field and prepare for the landing as follows:
Pull mixture to idle cut-off position
Turn fuel selector valve to “OFF”
Turn all switches “OFF”
Approach at 90mph
Extend wings flaps as necessary within gliding distance of the field
Unlock cabin doors
Land in a slightly tail-low attitude
Apply heavy braking
Upon entering the clouds, and immediate plan should be made to turn back as follows:
Note the time on the clock and the compass heading
Initiate a standard rate left turn, holding the turn coordinator symbolic airplane wing opposite the lower left index mark for 60 seconds. Then roll back to level flight by leveling the turn coordinator
Check accuracy of the turn by observing the compass heading which should be the reciprocal of the original heading
Maintain altitude and airspeed by cautious application of elevator control. Avoid over controlling by keeping hands off the stick and steering only with the rudder
Recovery from a Spiral dive
Close the throttle
Stop the turn by using coordinated aileron and rudder control to align the airplane in the turn coordinator with the horizon reference line
Cautiously apply elevator back pressure to slowly reduce the indicated airspeed to 110 mph
Adjust the elevator trim control to maintain a 110 mph glide
Keep hands off the control stick, using rudder control to hold a straight heading
Check engine operation occasionally, but avoid using enough power to disturb the trimmed glide
Upon breaking out of cloud (assuming you’re in it), apply normal cruising power and resume flight
Turn fuel selector valve to “OFF”
Pull mixture control to idle cut-off
Turn master switch “OFF”
Establish 120 mph glide
Close cabin heat control
Select a field suitable for a forced landing
If fire is not extinguished, increase glide speed in an attempt to find an airspeed that will provide and incombustible mixture
Execute a forced landing
Electrical fire in flight
The initial indication of an electrical fire is the odor of burning insulation. The immediate response is to turn the master switch “OFF”. Then close off ventilating air as much as practical to reduce the chances of a sustained fire. If electrical power is indispensable for the flight, an attempt may be made to identify and cut off the defective circuit as follows:
Master switch “OFF”
All other switches (except ignition) “OFF”
Check condition of circuit breakers to identify faulty circuit if possible. Leave faulty circuit deactivated
Master switch “ON”
Select switches on successively, permitting a short time delay to elapse after each switch is turned on until the short circuit is localized
Make sure fire is completely extinguished before opening vents
Flight in Icing conditions
An unexpected icing encounter should be handled as follows:
Check Pitot heat “ON”
Turn back or change altitude to obtain an outside air temp that is less conducive to icing
Pull cabin heat air control to get maximum defroster heat and airflow
Increase engine speed to minimize ice build-up on the propeller blades
Watch for signs of induction air filter ice and regain power by increasing throttle setting
Plan a landing at the nearest airport. With an extremely rapid ice build up, select a suitable off airport landing site
With an ice accumulation of ¼” or more on the wing leading edges, be prepared for significantly higher stall speed
Leave the 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
Approach at 90 to 100 mph, depending on the amount of ice accumulation
Perform a landing in level attitude
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