Emergency Procedures

■ Increase Load Factor - Recall that as an airplane banks, it experiences a higher load factor (g-force), which causes the wing to produce more lift (fly at a higher angle of attack), thereby increasing induced drag. An airplane which is banking at 45 degrees, Prepared by: Ryan Binns (ryancbinns.com/flying), February 2020 PPL (IX-A) / CAX (IX-A) / CFI (XIII-D) 4 for example, has a load factor of 1.4g. As the load factor increases, the angle of attack increases, the induced drag increases exponentially. ■ Go Fast - Pilots also know from basic aerodynamics that drag also increases rapidly as airspeed increases. By flying as fast as possible (generally, at Vne if conditions allow, otherwise at Vno in turbulent air), drag can be increased. ■ Configure - Some airplanes specify that emergency descents should be made with landing gear extended (for retractable gear), or with flaps down, etc. These configuration changes all add drag, however they also generally reduce the maximum allowable airspeed. Refer to the Airplane POH to determine the correct configuration and airspeed for an emergency descent. ● Don’t Just Nose Over - When beginning the pitch down for Vne, pilots might attempt to just push the pitch down to accelerate. A rapid pushover creates a <1g load factor, which initially reduces drag, as well as creates a risk of a negative-g or 0-g situation. The emergency descent should be flown with a positive load factor continuously throughout the maneuver to maximize drag and avoid the <1g area of the envelope. Prepared by: Ryan Binns (ryancbinns.com/flying), February 2020 PPL (IX-A) / CAX (IX-A) / CFI (XIII-D) 5 ○ Entry - Generally, the proper entry for an emergency descent is to reduce power to idle, begin a 30-45 degree banked turn, and lower the pitch angle to accelerate to Vne or Vno, as appropriate. ○ Spiral - In order to maintain positive load factors throughout, and to remain over a potential emergency landing area, an emergency descent is often flown as a steep, spiraling descent. In most cases, the objective is to rapidly descend to a suitable landing area where an emergency approach and landing can be executed. Therefore, a good point on the ground to spiral over is the ‘downwind key position’ for the eventual emergency landing location. Prepared by: Ryan Binns (ryancbinns.com/flying), February 2020 PPL (IX-A) / CAX (IX-A) / CFI (XIII-D) 6 ● Diagnosis and Emergency Checklists - Before and during the emergency descent, it is important that pilots attempt to diagnose the problem, and perform the emergency checklists. The emergency checklist items may resolve the situation that is causing the emergency descent! ○ For example: In an engine fire emergency, the emergency checklist will instruct pilots to cut off the fuel supply to the engine, which may assist in extinguishing the fire. ● Managing the Bank Angle - In order to remain over the selected emergency landing area, the angle of bank must be varied throughout the maneuver to account for the wind. As groundspeed decreases while upwind, less bank is required, but as groundspeed increases while downwind, more bank is required. Constantly changing bank will require close attention to the coordination of the turns. The emergency descent should be flown between 30 and 45 degrees of bank. Prepared by: Ryan Binns (ryancbinns.com/flying), February 2020 PPL (IX-A) / CAX (IX-A) / CFI (XIII-D) 7 ● Recovery - Recovery from an emergency descent should be made gently, as the airplane is very likely being flown over maneuvering speed. Do not continue the emergency descent below 1,000ft AGL, and ensure that recovery is started early enough so that the airplane can slow to prepare for an emergency off-airport landing. ● Safety Considerations ○ Clearing Turns - An emergency descent will involve flight at very high speeds and across a very large vertical section of sky. It is important that pilots thoroughly clear the area, especially directly below the airplane. ○ Checklists - Pilots should complete a pre-maneuver checklist before beginning the maneuver. ○ Visual Traffic Scanning - Pilots must remember to keep up their traffic scan throughout the maneuver. ○ Clearing the Engine - Because the maneuver is performed while the engine is at idle for an extended period of time, carb heat may be required, and the engine should be periodically cleared (brought up to high power briefly), at least once per revolution, to prevent spark plug fouling. ○ Never Exceed Speed - For the purposes of simulation, it is often better to fly the airplane at Vno. The airplane can never be allowed to exceed Vne! Maneuver Description ● Maneuver Start - Usually the instructor or examiner will indicate that some kind of emergency is occurring. When a simulated emergency occurs that would warrant an emergency descent, initiate the maneuver. ● Clear The Area - Clear the area around the airplane, especially directly below. ● Emergency Checklist - Depending on the type of emergency, reference the appropriate emergency checklist and complete any steps necessary before beginning the emergency descent. ● Configuration and Airspeed - Depending on what the emergency checklist and POH call for, configure the airplane and descend at the appropriate speed. (Usually Vfe with flaps extended, or Vno/Vne with no flaps) ● Select a Suitable Emergency Landing Area - Once the descent has begun, find an open field or other area, free from obstacles, that will allow landing into the wind, or with a manageable crosswind. ● Bank Angle - Select a bank angle initially between 30 and 45 degrees, varying the bank angle to maintain a nearly constant radius over a possible emergency landing area. Because of the varying ground speed, this bank angle will not be constant. Aim to bank no less than 30 degrees, both to maintain positive load factors and to ensure each revolution will not lose excessive altitude and require the maneuver to be started at an impractically high entry altitude. ● Recovery Altitude - Generally, the emergency descent should be completed no lower than 1,500ft AGL. Allow for enough altitude to make it to a position from which a power-off approach and landing can be executed. ● Coordination - To spiral around the emergency landing area, the angle of bank will vary, which will require close attention to coordination. Proper coordination must be maintained at all times, as banking steeply at relatively low altitudes requires caution to avoid a stall or spin. Prepared by: Ryan Binns (ryancbinns.com/flying), February 2020 PPL (IX-A) / CAX (IX-A) / CFI (XIII-D) 8 ● This is a visual maneuver! Eyes should remain outside the cockpit as much as possible to scan for traffic and ensure proper tracking of the target emergency landing area. Expanded Completion Standards ● The pilot can explain the purpose of the emergency descent maneuver, when the maneuver should be performed, and how load factor affects the performance of the maneuver. ● The pilot can perform the maneuver to the following standards: ○ At the direction of the instructor or examiner, determine the nature of the emergency and consult the appropriate emergency checklist. ○ Pilot clears the area, selects a suitable emergency landing area, configures the airplane, and begins a descent at the highest speed allowable for the configuration, -10/+0 knots. ○ Pilot maintains positive load factors throughout the descent, with a bank angle between 30 and 45 degrees. ○ The pilot clears the engine once per revolution, maintains coordinated flight, and recovers at the specified altitude, +/- 100 ft. Prepared by: Ryan Binns (ryancbinns.com/flying), February 2020