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Comment by caconym_ | Hacker News Reader

IIRC they put a few other aircrews into the same scenario in simulators, and they all crashed. I think what the crew accomplished here is one of the most impressive and inspiring human feats I've ever heard of; more people should be familiar with the story.

Like, sure, Pearson had glider experience... but he applied that experience flawlessly in an aircraft with a brick-like glide ratio, landing with no slats or flaps, all the while losing control authority as the airspeed dropped and made the RAT less and less effective, with 69 human lives at stake. Holy shit.

For anyone who's interested, Wikipedia is full of these stories of disasters and near-disasters, and they make for interesting reading.

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A glide ration of 12:1 is not great, but isn't exactly brick-like either. A Cessna 172 has a glide ratio of about 9:1. Pilots spend a lot of time practicing gliding in airplanes like that (Cessnas, Pipers, etc) during primary training.

I doubt they practice it much in 767s, though, despite the fact that they actually glide better. :)

You usually don't practice gliding when learning how to fly a small aircraft, they simply don't glide very well.

What you of course do are power-off landings – on airfields, for example from the downwind, and simulated, i.e., you make a go-around just before landing, outside an airfield. Sometimes, it works, sometimes, it doesn't, there are many factors … that's why you actually fly with power idle and not with power off. There're still a few incidents, i.e., somehow the practice becomes tool real!

All in all, power-off landings and other emergency training are an important part of becoming a pilot but you don't spend that much time for them. Other things are much more time-consuming in a typical 45-hour syllabus.

Related fact: the glide ratio does not depend on the aircraft weight, only on the aerodynamic efficiency (the ratio between your lift and your drag), so it is useless to throw weight to reach further like maybe you have seen sometimes on movies. Less weight will make you descend slower but not further. Normally, the longer your wing, the higher your efficiency. See for example the pictures here: https://en.wikipedia.org/wiki/Aspect_ratio_(aeronautics)

Losing weight will reduce stall speed, allowing for a slower and safer landing. Modern competitive gliders carry a substantial quantity of water ballast - the extra weight improves glide speeds, but it can be jettisoned before landing.

I fly a paraglider with a 9:1 glide ratio and I think it's quite a good number, so 12:1 is definitely not brick-like to me..

You're recalling a different incident: engine-out problems are a routine part of flight training at every level.

You're thinking of https://en.wikipedia.org/wiki/United_Airlines_Flight_232

where so much of the plane broke that they had to invent a new way to fly it.

I can't turn up a reference right now, but like you say, in the next few years that failure was repeatedly simulated, and all the simulated planes crashed.

(IIRC, Haynes declined to try his hand at any of the simulations, explaining that the one time when it really mattered was enough for him.)

Looks like Wikipedia thinks they also simmed the Gimli Glider incident with other aircrews, though it may well be wrong: https://en.wikipedia.org/wiki/Gimli_Glider#cite_note-19

Flight 232 is another very interesting story, for sure.

You're right, thank you.

12:1 is actually not bad.. A classic glider trainer (SGS 2-33) in average condition is just a bit better.. The difference is the best glide speed. 50mph vs 150mph.

Slipping to lose altitude fast is a regularly trained maneuver for glider pilot.

Still an amazing feat to pull that landing.

The 2-33 is speced at a glide ratio of 22:1. You might be thinking of the 2-22 which is speced at 17:1.

As someone who learnt to glide on modern (30:1 glide ratio) glider, those numbers make me think of truly ancient hardware...

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