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Last week, 767 landing at Newark, high winds, a good deal of rocking in the last few minutes, some passengers quite distressed. The landing was harder and noisier than usual, and we immediately floated upwards, must have been a couple of seconds before we landed again.

The question I have is - in these circumstances (high winds), would the pilots have been flying the landing with a little less flare than usual and anticipating the bounce as a way of shrugging off some speed / energy; or, is it something you never quite know if it's going to happen or not, and would rather didn't happen at all?

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    $\begingroup$ Firm landings are entirely intentional in strong winds, as the answers say though, the bounce is not. $\endgroup$
    – Ron Beyer
    Jan 27, 2019 at 16:18
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    $\begingroup$ The "noise" may have been the reverse thrust of the jet engines working a little harder. Bouncing up a few feet isn't perfect, but it is one reason the main gear is supported by the strongest part of the plane, the wing spar structure. $\endgroup$
    – Robert DiGiovanni
    Jan 27, 2019 at 17:28

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Bouncing a landing is neither intentional nor desirable. There are several reasons why a student pilot might bounce, but for a professional pilot, it's most likely related to wind gusts, which are a challenge no matter how much training and experience you have.

Gusts are by their nature unpredictable, and if one hits the plane right as it's touching down, it can suddenly lurch upward and/or downward, resulting in a bounce. That's probably also why your plane was "rocking" before landing.

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    $\begingroup$ It's a problem with physics. Since your wings are generating lift, if a gust of wind hits the right way, then you will have a sudden change of lift that the pilot cannot respond to. $\endgroup$
    – Nelson
    Jan 28, 2019 at 4:28
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    $\begingroup$ bouncing is not desirable - I'll say: youtu.be/_wpOkUUCoZ8 $\endgroup$
    – Baldrickk
    Jan 28, 2019 at 10:57
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    $\begingroup$ Skip to 1:10 in that video unless you have a thing for looking at clips of heavy fog. $\endgroup$
    – User1000547
    Jan 28, 2019 at 21:11
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Bounces are bad news on airliners because you are becoming airborne again just as the lift dumpers pop out, which makes the second touchdown even more exciting and often leads to hard landing inspections, and in extreme cases broken gears.

The lift dump spoilers are supposed to limit bouncing tendency, but if you come down hard enough there is so much energy stored and released they don't come out fast enough or they are ineffective initially when they do or on some airplanes they won't even be triggered until the nose wheel is down.

When you have a significant bounce on a jet you aren't supposed to try to save the landing. It should be "go around - set thrust" and get out of there. It's called a "Balked Landing" which is a go-around initiated in a low energy state close to the ground. You MUST get the lift dumpers retracted, or prevent them from coming out, and setting go-around thrust will do that. You may touch down again and probably will, but you are supposed to continue with the go around.

There was an Air Canada Jazz RJ that bounced on landing and they tried to save the landing, but the bounce was so high and the lift dumpers were out so they collapsed one of the main gears on the second landing.

Like everything, there are nuances; a little skip, maybe only one gear touched, maybe they feel a balked landing procedure is more dangerous in gusty crosswinds than just landing, so a lot of crews will try to save it. So maybe this crew did a bad thing, maybe not. Without a lot more details, hard to say.

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    $\begingroup$ So the second landing is the pancake if the spoilers deploy. The Space Shuttle used a much shorter nose gear to make sure AOA was insufficient for flight while it was rolling out. Seems spoilers and reverse thrust could wait until mains were definitely down. I would build 5 mile runways for you all. $\endgroup$
    – Robert DiGiovanni
    Jan 28, 2019 at 6:33
  • $\begingroup$ Most airplanes only require both mains to be on the ground, plus several other parameters to be satisfied, weight on wheels, wheel speed, thrust at idle, fan speed near idle, etc in various and/or combinations for ground spoiler deployment. Another big no-no in jets is landing with power ahead of idle. If they are too far foward, the GLDs may not come out at all, and if you skip and then go "oops" and pull them back, enough other parameters may still be satisfied to make them deploy while you are several feet in the air and you'll come down hard. $\endgroup$
    – John K
    Jan 28, 2019 at 13:33
  • $\begingroup$ The bad on is when the nose gear slams and the plane starts to "porpoise". Generally a bounce is handled simply by allowing a little more air speed to bleed off, with gradual increase in yoke back pressure as it does. End of the runway with large/heavy would be a concern. $\endgroup$
    – Robert DiGiovanni
    Jan 28, 2019 at 17:22
  • $\begingroup$ If you touch nosewheel first, you are by definition way too fast. You can handle bounces on regular airplanes that way, but not on airplanes with lift dumpers. It's straight to the Balked Landing procedure for anything significant. $\endgroup$
    – John K
    Jan 28, 2019 at 22:43
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The reason an aircraft "bounces" on touch down is that it is going too fast to "settle" on the runway. Bouncing is far better than "pancaking" from 15 feet off the ground because you were going too slow. The difference is only a few knots in airspeed, especially for light GA aircraft.

Landing in gusty or variable winds will never be a perfect science. A light bounce only means the pilot erred on the side of caution, with plenty of runway to do it.

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    $\begingroup$ A 767 is hardly a "light GA aircraft". $\endgroup$
    – Martin Bonner supports Monica
    Jan 28, 2019 at 13:40
  • $\begingroup$ R/C is another notch down. Larger mass to S/A ratio would allow for finer speed control in wind. Agree that bounce is undesirable. Good management of it definitely is. Still think if they can build thousands of miles of rail road track and interstate highway, they can give pilots a few more feet of runway. $\endgroup$
    – Robert DiGiovanni
    Jan 28, 2019 at 17:12
  • $\begingroup$ @RobertDiGiovanni I hear you about a few more feet - my dad was a pilot in the RAF in the 1950's and 1960's, with numerous landings at Hot and High locations in the middle east and Africa. He told of some hairy episodes at both Nairobi and Salisbury (now Harare) flying a Bristol Britannia. The main issue in some places is finding the space. Take a look at San Jose airport on Google maps - there's simply no room for another foot, not with those freeways at both ends of the runway. $\endgroup$
    – dgnuff
    Jan 29, 2019 at 7:26
  • $\begingroup$ @dgnuff And that's why we have EMAS. :) $\endgroup$
    – reirab
    Jan 29, 2019 at 21:55
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Usually bouncing is completely undesirable, because this will increase your landing distance quite significantly to the extend you might overrun the runway if you don’t go around.... so better avoid it...

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