Engine Failure: The First 60 Seconds, and Where an EFB Fits

By Vincent Wu, founder of Ascent EFB. Last updated November 10, 2026.

TL;DR: Aviate, navigate, communicate. Pitch for best glide from your POH, pick a field and commit, run your POH or AFM emergency checklist, then declare: MAYDAY three times on the frequency in use or 121.5 MHz, and squawk 7700 if you cannot reach anyone right away. An EFB helps mostly with finding a reachable field. It cannot fly the airplane, and Ascent cannot transmit. Mayday Assist, arriving in Ascent 1.9.6, copies 121.5 and 7700 for you to tune and set by hand.

What should you do in the first minute after an engine failure?

Fly the airplane first: lower the nose and hold the best glide speed from your POH. Pick the most suitable field within reach and commit to it. Run your POH or AFM emergency checklist. Then declare: MAYDAY three times, on the frequency in use or 121.5 MHz, and squawk 7700 if you cannot immediately reach ATC.

This is not instruction and does not replace your POH, your AFM or an instructor. It is published FAA guidance, organized for the moment you need it.

Aviate: pitch for best glide before anything else

The Airplane Flying Handbook (FAA-H-8083-3C) defines best glide as the airspeed at which the airplane travels the greatest forward distance for a given loss of altitude in still air, at the highest lift to drag ratio. Faster or slower glides less far. Chapter 18, listing the errors pilots make under stress, names failure to lower the nose to maintain flying speed first.

Your number is in your POH, labeled best glide speed and sometimes written Vg. Know it cold, and know whether your book gives different figures by weight; the handbook notes a heavier airplane needs a higher airspeed for the same glide ratio. Trim for it.

On the climbout, the handbook says lower the nose, establish the glide attitude, and land straight ahead or with a slight turn, usually the lowest risk option. A turn back is only for a pilot certain the airplane can make it, who has trained the maneuver in that make and model.

Navigate: choose a field, then stop choosing

Chapter 18's terrain selection section is short and worth rereading. Your choices depend on the route you planned, your height above the ground, and any excess airspeed you can trade for distance. From altitude, pick the general area first and the exact spot later, because terrain is misleading from up high and altitude goes while you stare. Discard the first plan for an obviously better one, but as a general rule change your mind no more than once: a well executed landing in poor terrain can be less hazardous than an uncontrolled touchdown on an established field.

When you have time to plan the approach, the handbook names three factors: wind direction and velocity, the dimensions and slope of the field, and obstacles on final. They rarely agree, so aim for the combination that leaves margin for error. Touch down at the lowest controllable airspeed you can, because doubling groundspeed quadruples the destructive energy.

The flow: your POH, not a universal checklist

There is no universal engine failure checklist. The handbook opens its emergency chapter by saying its guidance is generic and that the manufacturer's procedures in the POH or AFM take precedence.

In many piston singles the restart items touch fuel, mixture, ignition and carburetor heat or alternate air, but which items, in what order, and with what settings is the job of your book. Memorize the immediate action items for the airplane you fly, then read the full checklist if time allows. The handbook is explicit that positive control on final comes before checklist tasks.

Communicate: how to declare

AIM 6-1-2 says you are in at least an urgency condition the moment you become doubtful about anything that could affect safety, and that this is the time to ask for help. An engine failure is distress.

AIM 6-3-1 says a distress call should begin with MAYDAY, preferably said three times, and that distress traffic has absolute priority. The frequency you are on, or one ATC assigned, is preferable. If needed, 121.5 MHz is guarded by direction finding stations, some military and civil aircraft, military towers, most civil towers and radar facilities, with range generally limited to line of sight.

AIM 6-3-2 says keep your assigned code while in radio contact unless told otherwise, and squawk 7700 with Mode C if you cannot immediately establish communications. AIM 6-2-2 adds that 7700 normally triggers an alarm at radar control positions, but you might be outside radar coverage, so keep trying the radio.

AIM 6-3-2 also lists what to say, as many elements as necessary, preferably in this order. You say it yourself; Ascent cannot transmit it.

1. MAYDAY, MAYDAY, MAYDAY
2. Name of the station addressed
3. Aircraft identification and type
4. Nature of the distress
5. Weather
6. Your intentions and request
7. Present position and heading
8. Altitude
9. Fuel remaining in minutes
10. Number of people on board
11. Any other useful information

Callsign, the nature of the problem, position and intentions is a working start. No app makes that call for you: Ascent's Mayday Assist cannot transmit, and the radio and transponder are yours to work by hand.

Two more facts. Under 14 CFR 91.3(b), in an in-flight emergency requiring immediate action, the pilot in command may deviate from any rule of Part 91 to the extent required; under 91.3(c) you send a written report if the Administrator requests one. And per AIM 6-2-4, Cospas-Sarsat satellites stopped monitoring 121.5 MHz ELTs in 2009, so satellite detection needs a 406 MHz ELT, which the FCC requires be registered with NOAA. Know which your airplane carries.

Where an EFB fits, and where it does not

Mostly in the navigate step, and mostly because of work done on the ground. A tablet cannot hold best glide for you, and every second heads down is a second not flying. What it can do is answer one question faster than mental arithmetic: which fields can I still reach, given my altitude and the wind? That only works if your glide numbers, your checklist and offline data for the route are in the app before you fly.

What Mayday Assist does in Ascent 1.9.6

Mayday Assist is arriving in Ascent 1.9.6; the App Store build today is 1.8, which does not have it. This is what it does, checked against the 1.9.6 release code. It never makes a call, sets a squawk or reports your position to ATC or rescuers.

You start it. You tap the Mayday button on the map; nothing starts automatically. The map switches to what picking a field needs: airports on, navaids, airways and fixes hidden, airspace, TFRs, traffic, weather hazards and terrain still visible. Exiting restores your layers.

Airports within 150 NM, ranked by reach. Each row shows distance, bearing, elevation and a frequency where one is known. Offline, it falls back to an on-device list and says so; that list has frequencies only where an offline pack is installed, and cannot tell you whether a field is open.

Glide reach from your POH numbers. You enter your aircraft's best glide speed and glide ratio once. Ascent combines them with GPS altitude and the wind at altitude, from the online forecast or, offline, FIS-B winds from a connected ADS-B receiver. Where offline 3D terrain covers the way it checks the glide against the ground; elsewhere it assumes flat ground at a reference elevation, and the panel says which. It takes 20 percent off your glide ratio by default, adjustable from none to 50 percent. Turns and obstacles are not included. One tap on Fly direct starts Direct-To.

Your checklist, not ours. If you have entered your aircraft's emergency checklist, it opens in the panel and can be pinned beside the map. Ascent ships none of its own; the procedures belong to the aircraft.

Guard and squawk, copied for you. The Guard 121.500 and Squawk 7700 cards copy the value when tapped. The caption above them reads: "Mayday cannot transmit. Tap to copy a value, then tune and call by hand." You set the transponder and tune the radio yourself.

Share Position. This opens the iOS share sheet with a plain text report: position, GPS altitude, nearest airport and a map link. The report goes nowhere until you pick an app and send it yourself, and the text says it was not transmitted to any emergency service or air traffic control, so the recipient does not assume rescuers have it.

Spoken callouts, off by default. Turned on, they speak short advice: best glide speed and best field on entry, a better field when one takes over, no field within glide, and the Direct-To field coming up.

The panel carries a standing notice: "Advisory only. Verify POH/AFM and ATC instructions."

What it does not do

The failure we worry about most is a pilot believing help is on the way because they tapped a red button. So, plainly, Mayday Assist in Ascent 1.9.6:

• Never transmits a distress call and never contacts ATC, search and rescue, or emergency services.
• Does not set your transponder or tune your radio. You set 7700 and tune 121.5 yourself.
• Does not report your position to anyone. Share Position only opens the share sheet; you choose whether to send.
• Does not detect an emergency, start on its own, or pick off-airport landing sites.
• Does not model turns or obstacles, and checks terrain only where offline 3D terrain covers it.
• Does not replace your POH, AFM, ATC instructions or looking outside, and is not a certified system.

Practice it on the ground

Once Ascent 1.9.6 is on your iPad, enter your glide numbers and your emergency checklist. Then sit in the airplane, tablet in airplane mode, and run the whole thing: open Mayday Assist, find the top field, tap Fly direct, read the guard and squawk cards, then reach for the real radio and the real transponder. The goal is that your hands know the call happens on the radio and transponder, not the screen. Then fly a simulated engine failure with an instructor. That is the training that matters.

Sources

• FAA, Airplane Flying Handbook (FAA-H-8083-3C), Chapter 18: Emergency Procedures: emergency landings, psychological hazards, terrain selection, approach, engine failure after takeoff.
• FAA, Airplane Flying Handbook (FAA-H-8083-3C), Chapter 3: Basic Flight Maneuvers: best glide airspeed, glide ratio and weight.
• FAA, Aeronautical Information Manual, Chapter 6, Section 1: General: 6-1-1 pilot responsibility and authority, 6-1-2 request assistance immediately.
• FAA, Aeronautical Information Manual, Chapter 6, Section 2: Emergency Services Available to Pilots: 6-2-2 transponder emergency operation, 6-2-4 emergency locator transmitters.
• FAA, Aeronautical Information Manual, Chapter 6, Section 3: Distress and Urgency Procedures: 6-3-1 distress and urgency communications, 6-3-2 obtaining assistance and the message elements.
• eCFR, 14 CFR 91.3, Responsibility and authority of the pilot in command.

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Written by Vincent Wu, founder of Ascent EFB at Geospatios. FAA handbook and AIM text was read from faa.gov, and 14 CFR 91.3 from eCFR, on November 10, 2026. Mayday Assist behavior was checked against the Ascent 1.9.6 release code; the App Store build today is 1.8. Mayday Assist cannot transmit and is advisory only. Any EFB, including this one, is a supplemental aid, and final authority rests with the pilot in command.