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What is the ideal landing vertical speed for an airliner?

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Hey guys..I was just wondering what the ideal landing vertical speed is, so you don't bounce but also it's not really a hard landing. I've been flyin the 767 and according to FS flight tracker they have been anywhere from -65fpm to -270fpm, mostly around -140fpm. Are these stats okay? It doesn't seem like I am landing hard, but when I exceed 200fpm sometimes it does. I was wondering how it differs, if it does, with a 767/747 and different kinds of planes.-Justin

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Guest Caveman

The ideal vertical landing speed is zero. In theory a properly executed landing approach will place the aircrafts gear on the runway the instant the plane is reaching its minimum flying speed for it's current (landing) configuration.The plane should not "drop" to the runway (underspeed), nor "fly" to it (overspeed).The *best* landing is one uses all the aircrafts "energy" the instant the wheels touch the tarmac so it is a question of "timing" rather than setting the vert speed to some value and just "plopping" plane on the runway.You will definitely have a neg rate of descent for any given plane that will be more or less constant as the aircraft is sliding down the glideslope depending on its approach but this neg rate of decent should climb back towards the zero line as the nose is brought up in a higher angle of attack during the "flare" and reach zero at the end of the flare when the wheels hit the tarmac.There are many variables of flight making changes during this phase of the landing; most of which are non-linear, but with practice, a no bounce, smooth landing can be made.

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Guest The Ancient Brit

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>whatever you have set in the vertical speed, it will reduce>the rate to almost zero. With the autothrottle disengaged the>aircraft slows down to IAS120 or less and gently, ever so>gently, descends that last few feet.I don't think this particular method would be "approved" by airlines. And it would definitely violate all kind of FAA rules when used in minimum (cat I) weather.Michael J.http://www.reality-xp.com/community/nr/rsc/rxp-higher.jpg

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Guest The Ancient Brit

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Guest Stamatis

The landing gear is designed to take about 600 fpm drop.I am sure I had read that the design limit for airliner's landing gear is a lot higher than 600 fpm...Stamatis

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Guest

I can't speak for the newer 767's, but for the 707 variant I fly for the USAF, we don't watch the VVI on the landing. If anyone is, then they are plain wrong. Emphasis on the landing flare is maintaining centerline alignment, proper crosswind controls and visual detection of the appropriate pitch for a nice flare. This is one of the few times flying a heavy aircraft that "monkey skills" are required. However, our DASH-1 states that if above 235K lbs, a heavy landing is anything greater than 500 VVI. Another reason that VVI isn't used is that the pitot static instruments do not work properly in ground effect because of installation error and increases pressure from air deflection (ground effect). "Greasing" a landing is, contrary to popular belief, not a good thing. Heavies are supposed to be landed "firmly", especially on wet runways because you have to break the water surface or else you hydroplane. A good landing is defined as crossing the runway threschold at 35-50 ft, and landing in the first 1000-2000 ft. (this varies by aircraft but the idea is the same). If you do not land within those parameters, you are invalidating your landing data and it could have catastrophic results. Case in point, keep the nose up and attempting aerobraking as long as possible will guarantee that your landing distance will exceed the available runway most likely. Landing is a science in itself, and it's not as simplistic as FS makes it seem.

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