Transport Episode 2 Sources: 5

Why don't planes fall out of the sky when the engines go quiet?

Watch it on

The short answer

Wings, not engines, hold a plane up, so a jet with dead engines becomes a heavy glider that trades height for distance.

Plane wing: shine the torch to look inside

The full explanation

A jet with no engines still flies. So why doesn't it drop? Wings hold planes up, not engines.

Air rushing over the wings makes lift. Engines off, gravity tips it into a shallow glide. The wings keep working.

An airliner covers fifteen to twenty metres for every metre it drops. In 2001, an Air Transat jet ran dry over the Atlantic. It glided about one hundred and twenty kilometres to the Azores.

All three hundred and six people survived. Follow Insidely for how everyday things actually work. That's how a jet with no engines still flies.

Sources

Insidely's promise: every fact in this episode comes from these sources.

  1. Glide ratio means more distance travelled for each unit of height lost, and a higher lift-to-drag ratio gives a shallower glide: NASA Glenn Research Center, https://www1.grc.nasa.gov/beginners-guide-to-aeronautics/drag-to-lift-ratio
  2. Airliners glide about 15 to 20 metres for every metre they drop: a typical narrowbody jet (A320, 737) about 17 to 1, and widebodies such as the A330 or 777 about 18 to 1 to 20 to 1: Migflug, Both Engines Dead: Can Jets Survive?, https://migflug.com/jetflights/?p=804281
  3. Air Transat 236 (Airbus A330-243, 24 Aug 2001), 13 crew and 293 passengers on board, both engines out from fuel exhaustion, glided to Lajes in the Azores: official Final Investigation Report 22/ACCID/2001 by Portugal's GPIAA (2004), copy hosted by the US Federal Aviation Administration, https://www.faa.gov/sites/faa.gov/files/2022-11/AirTransat236_AccidentReport.pdf
  4. The aircraft was about 65 nautical miles (about 120 km) from Lajes when the second engine flamed out: Peter B. Ladkin, University of Bielefeld, Air Transat Flight 236: The Azores Glider (2004), https://rvs-bi.de/publications/compendium/incidents_and_accidents/Ladkin-AirTransat.pdf
  5. The fuel leak came from an incorrectly fitted part, and all 306 people survived: Simple Flying, https://simpleflying.com/azores-glider-the-story-of-air-transat-flight-236/ and Migflug, https://migflug.com/jetflights/air-transat-236-azores-glider-no-engines/

Spotted a mistake? Tell us on Instagram @insidely.hq.