On Fri, 22 Apr 2005 18:40:03 +0200 (CEST), Nomen Nescio
] wrote:
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From: Rolf Blom
"Bounced landing"?
What's that?
It's when you land too fast, and the plane still has enough lift to
bounce you back up; you can start oscillating or 'gallop' if you use
elevator to get back down, since lowering the nose adds speed & lift
again. Can be a nasty roller-coaster ride along the runway.
I'd really not call that a bounce as it's usually referred to as a
porpoise.
Thanks for taking the trouble to offer an answer, but I was trying to make
a (obviously poor) joke.
In 30 years I've never bounced a landing. Not even as a student.
I've had some I'd call ricochets:-))
I've "skipped" a couple of landings where the wheels lightly graze the
the runway a couple of times. And I've done, um, let's say 1 or 2 landings
where I thought about visiting a dentist to see if I loosened a couple of fillings
on touchdown. But I've never contacted the runway hard and fast enough to
put the plane back in the air.
That makes you a very rare individual indeed.
This thread actually has me a bit concerned that I'm destined to become
one of those "experienced" pilots that finds themselves in an NTSB
report the first time they DO bounce a landing! How the hell do you practice
a bounced landing if you've never done one?
This is my opinion.
I'm not sure just how serious this is but ... Landings are bounced due
to excessive speed, AND/OR landing on the nose gear first.
There are also gusty winds where you touch down nicely and then get
hit by a strong gust that lifts the plane as much as 10 feet. There
are some who wouldn't call this a bounce, but it will be if not
properly handled.
If the bounce is due to a gust, REMEMBER you are flying but you do not
have enough speed to keep flying and that gust will not last forever.
It the gust only lifted you a little, set it back down, but anything
more than a little is time for power. If it's high enough that
dropping in from that height is going to break or bend something
important put the power in and go around.
"When in doubt, go around!"
In many planes it is very difficult to get it on the mains first when
you have excessive speed. In this case the pilot recognizes the
excess rate of descent and pulls the nose up and the plane contacts on
the mains. Unfortunately he now has the nose up and when it rebounds
off the mains plus the lift it's back up and sometimes for quite a
distance. *Typically* easing the nose into the proper position at the
proper time will fix it as there is still enough energy to flare.
_BUT_NOT_ALWAYS! They sometimes do take just a shot of power.
"When in doubt, go around!"
If the plane is coming in at a too high a speed in a normal attitude
the nose gear will contact first, bringing the nose up as the mains
are continuing down. This results in a rather steep nose up rebound.
Instinct is to get the nose down, but usually too much and there is
not enough energy left to flare which makes the next bounce even
higher. This is called a "Porpoise" as it imitates the actions of
one. Usually they end up busting the nose gear on #3. Every one I've
seen did 3 and broke the gear.
The remedy is a timely application of power.
A Porpoise is *dangerous* and it's better to swallow one's pride and
just go around. Those of us who have done enough of them (yes I admit
it) can often apply power and controls in such a manner as to salvage
many of these, but the old adage still holds true:
"When in doubt, go around!"
I fly in just about any kind of weather except ice and in
thunderstorms. I've flown in strong, gusty winds, and even gusty
cross winds since early on as a student. That being the case, I've
bounced, porpoised, and ricoched my way down many a runway.
I also practice right up to the airplane's limits(and mine) for cross
winds which are over double the "demonstrated cross wind component" in
the POH.
I also like to practice short field landings using everything from a
stabilized pattern to a steep slipping U-turn to the runway. This too
has resulted in a few rather un elegant landings, some of which even
the term *arrival* is a bit kind.
I was watching some crop dusters yesterday. The winds were picking up
and gusty. One made three landings before it was down to stay. Those
guys have experience most of us will never approach.
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Roger
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