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I regularly fly in a PC flight simulator, and I'm currently trying to refine landings in medium-to-large airliners in various weather conditions.

A problem I've faced in some conditions while flying the 737-800 has been bouncing on touchdown, where I lose just enough lift in the last few feet of my approach to touch down firmly on the main gear only, before bouncing back up 5-10 feet.

While I'm already looking into avoiding this kind of bounce whenever possible, I'd like to know what common procedures are in this situation assuming the gear is left intact and there's no urgent failures or factors (such as a fuel emergency) which would time-constrain a landing. Specifically; would a real-world flight in this situation go around, adjust thrust, adjust flare, or do something else entirely?

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    $\begingroup$ 5-10 feet, you're probably going too fast, and the bounce is more of a "refusal to stop floating"... $\endgroup$
    – SnakeDoc
    Jan 23, 2018 at 21:02
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    $\begingroup$ You might want to read up on FedEx Flight 14 and FedEx Flight 80. $\endgroup$
    – user
    Jan 24, 2018 at 15:51
  • $\begingroup$ MD-11 is notoriously famous for its flight characteristics if bounced. It should not be considered a common example when discussing a bounced landing. $\endgroup$
    – Jpe61
    Dec 3, 2019 at 5:34
  • $\begingroup$ The dynamics affecting the aircraft during the seconds surrounding touchdown are fairly complicated (e.g. ground effect, landing gear strut damping, airframe structural modes). PC simulators typically do not model these accurately. $\endgroup$
    – pericynthion
    Dec 3, 2019 at 6:43
  • $\begingroup$ in addition to what @pericynthion states, many PC flight simulator flyers tend to focus too much on making silky smooth landings, often ending up floating a lot and then forcing themselves down hard when they notice they're not touching down normally. An airliner should land firmly but gently, so with enough vertical speed to stay put but not enough to cause damage or bouncing. Forget about that 1m/s touchdown speed, 100 is fine :) $\endgroup$
    – jwenting
    Dec 5, 2019 at 7:29

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Well, "5 to 10 feet" is not "slightly." One or two feet is "slightly," and in that case you can maintain your landing attitude or pitch very slightly nose-down -- really a matter of the slightest change in pressure, not really a perceptible change in pitch -- and you'll land soon after that.

However, for a larger bounce, the concern, especially on the longer 737's, the -800 and -900 and -900ER, is a tail-strike. The tail skid protects the tail from a strike on takeoff, but on landing the geometry is different and the skid won't be what contacts the runway; it will be the fuselage. And while tail strikes on takeoff are more common, it's the tail strikes on landing that are far more damaging & expensive. So avoiding one of those is a major concern. Thus, the usual guidance in the event of a bounced landing in the 737-800 is not to attempt to salvage the landing, but rather to go around. You may touch down again during the go-around, and that's okay, but you're better off aborting the landing & taking it around to try again, than to risk damaging the aircraft by trying to recover from a high bounce.

One thing that complicates recovering from a bounce is the fact that your spoilers may have extended when you touched down the first time -- and the last ten feet to the runway with spoilers fully extended & power already at idle, won't look nearly the same as the usual last ten feet to the runway, with power coming off & no spoilers. You'll settle fast, and hard, and you won't have the elevator authority you're used to for adjusting the sink rate. You can pull back, but the change in attitude probably won't arrest the sink rate the way you think it will -- you'll just hit harder & in a more nose-high attitude. Thus the increased risk of hitting the tail.

On a shorter aircraft without the tail-strike concerns (say a 737-200, -300, -500, -600, or -700), it might be possible to salvage the bounced landing, although 10 feet up is a pretty high bounce -- even if you had a lot of airspeed to play with and runway ahead of you, I'm not sure it would be wise trying to sort that situation out -- go around & try again.

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    $\begingroup$ I changed "and you'll land momentarily after that" to "and you'll land soon after that". In American English, momentarily means "after a moment"; in British English, it means "for a moment", so there's scope for confusion. (To a British person, "landing momentarily after a bounce" would suggest making a second bounce.) $\endgroup$
    – David Richerby
    Jan 24, 2018 at 16:16
  • $\begingroup$ @DavidRicherby Good to know! $\endgroup$
    – Ralph J ♦
    Jan 24, 2018 at 16:38
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    $\begingroup$ @DavidRicherby FWIW, both usages are valid in American English. They're usually just distinguished by context. $\endgroup$
    – reirab
    Jan 24, 2018 at 19:46
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Your first reaction should be to advance the throttles. Not all the way, but to around 40%. This keeps the plane flying and avoid it sinking onto the ground in an impact that might collapse the landing gear.

Your second instinct would be to avoid large or abrupt pitch changes. If you attempt to chase it, you might end up in pilot-induced oscillations. Forget about the VSI and radar altimeter, fly the AI. Pitch to about 2~3 degrees up.

That is why you always have one hand on the throttles and the other hand on the yoke while landing.

Now that you have accomplished all that, you can evaluate your options. What is the condition that caused the bounce? Is there a strong and gusty crosswind? Poor height judgment? Excessive airspeed? How likely is it that you can land it on the remaining runway? Are you trying to land on a 13,000 feet runway on a calm day, or 7,500 feet runway on a rainy night?

You need to make a decision quickly. Ralph J has already stated the things that can go wrong when you try to salvage a bounced landing, which I will not repeat here.

Also, as stated, a bounce to 10 feet in real life is a very hard bounce, and more than a few passengers will certainly be upset. Unless there is an emergency or fuel situation, a go-around is always an option. And the reason why pilots have license is to ensure they won't end up going-around every time until they run out of fuel.

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  • $\begingroup$ Glad you addressed the general case. $\endgroup$
    – mongo
    Jan 15, 2019 at 1:22
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I that case, you just have to keep the nose up at the same angle and you don't touch anything... Just wait to be back on the ground. This is the safest way because :

  1. if you put more engine power at this particular moment you will perform a very long landing and it's not safe at all.
  2. If you try to pull the nose up, you"ll risk to touch the tail.

To avoid to rebound, try to wait until 10 to 20 feet on a 737 (30 to 40 feet on a B777) on the radio altimeter and just retain a little bit (few degrees) the pitch command back with a firm and quite fast move and block the position of the pitch ( do not try to continue the backward movement ) On real airliner that's what we do and then the ground effect will normally play its role and you'll make a very soft landing.

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  • $\begingroup$ My concern is that this doesn't account for the possibility of running out of runway, and as @RalphJ mentioned, the possibility of a tail strike on longer airframes; but this is good advice if neither of those are factors. Thanks! $\endgroup$
    – Jules
    Jan 24, 2018 at 13:33

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