PA.IX.A.HOW· Procedure
How to fly the maneuver
How to fly an emergency descent: recognize, configure, enter the descent, recover
An emergency descent is the maneuver flown when rapid altitude loss is urgently required — in-flight fire, smoke or fumes in the cockpit, urgent medical issue, or cabin decompression (in pressurized airplanes; rare at PPL level). The pilot configures the airplane for maximum drag without exceeding structural limits, enters a steep descending turn, holds the airspeed within published limits, and levels off at the assigned altitude.
The structural limits don't suspend during an emergency. V_NE, V_NO, and V_LE / V_FE remain absolute. A pilot who exceeds them during a descent has converted one emergency into two — fire-on-board plus airframe failure. The descent is aggressive but disciplined.
Recognize the trigger
Conditions that justify an emergency descent:
- In-flight fire (engine, electrical, cabin).
- Smoke or fumes in the cockpit, especially toxic (carbon monoxide).
- Urgent medical event for pilot or passenger requiring rapid landing.
- Decompression (pressurized cabin types; rare at PPL).
The decision is immediate. Continuing at altitude to "think about it" while a cabin fills with smoke is wrong; descent is the response.
Configure for the descent
The configuration varies by airplane (POH is authoritative), but the standard pattern:
- Throttle to idle — eliminate thrust; prevent acceleration.
- Propeller to high RPM (full forward, if controllable prop) — increases prop drag.
- Mixture as appropriate — typically rich; some POHs specify lean.
- Carb heat off (carb heat is for cold-soak prevention; not relevant at high power on descent).
- Flaps: only if the airplane is below V_FE. At high airspeed approaching V_FE, do not extend flaps — the structural risk exceeds the drag benefit.
- Gear: if retractable and below V_LE, extend for additional drag.
The configuration takes about 5–10 seconds; the descent is already beginning as you complete it.
Enter the descent
The maneuver is a steep descending turn, not a vertical dive:
- Bank 30–45° in either direction (clear of traffic).
- Pitch down smoothly to establish the descent attitude.
- Accelerate to the POH-recommended emergency descent airspeed — typically near (but not exceeding) the lower of:
- V_NE (never exceed, in clean configuration).
- V_LE (max gear extended, if gear is down).
- V_FE (max flap extended, if flaps are down).
- Hold the airspeed near the limit. Some POHs specify a target like "V_NE − 10 KIAS" — use the published value if available.
The bank produces high drag (lift vector tilted, induced drag rises with √n), and the airspeed near the limit produces high parasite drag. The combination yields the maximum possible descent rate consistent with structural safety — often 2,000–4,000 fpm in a typical trainer.
Maintain through the descent
- Scan: altimeter (rate of descent), ASI (within limits), AI (bank + pitch attitude).
- Hold the airspeed at the target value. If approaching the limit, shallow the bank slightly to reduce descent rate without changing airspeed dramatically.
- Maintain positive load factor (IX.A.S2) — don't push negative g's. Smooth back pressure is required to hold the descent attitude in the banked turn.
- Trim is typically left alone or set forward; the descent attitude is held against control pressure during the maneuver.
Recover at the assigned altitude
- Lead the level-off by about 10% of the descent rate — same anticipation rule as the instrument climb / descent (VIII.B, VIII.C). At 3,000 fpm, lead by 300 ft.
- Roll out of the bank smoothly while pitching up.
- Add power to cruise as the airplane levels.
- Reconfigure to cruise (gear up if appropriate, flaps up).
- Level off at the assigned altitude in cruise configuration (IX.A.S3).
The recovery should be smooth, not aggressive. A snatch back to level produces high load factor — the same accelerated-stall trap that VIII.E nose-low recovery warns against. Pitch out after the bank is reduced; don't pull through a steep bank.
Common pitfall: exceeding V_NE during the descent. Once the airplane is in the high-drag configuration and steep bank, airspeed builds quickly. A pilot who's not watching the ASI overshoots V_NE — and the structural limit doesn't care that it's an emergency. Watch the airspeed; if approaching the limit, shallow the bank to reduce descent rate.
★ Next up
PA.IX.A.TOL · ACS tolerances
The Private Pilot Airplane ACS (FAA-S-ACS-6C, effective May 31, 2024) anchors emergency descent tolerances around POH-recommended configuration, structural l…