Wheelbarrowing and Flare

Has anyone seen wheelbarrowing occur? Prima facie, it appears too
improbable (ludicrous almost) a thing to happen but even the FAA
Airplane Flying Handbook copy that I have mentions it!

Also, while the ways of performing a flare is mentioned at many places,
the reason for a flare is conspicuously absent everywhere. Just why is
a flare needed vis-a-vis a 3-point landing? After all, birds just come
in and sit, without having to flare...

Ramapriya

Hi Ramapriya,

Ok, I'm game. It's Christmas morning here and I just work up.

You really need to start taking flight lessons. You have way too much
interest in all this to let it go to waste.

I'll answer your last question (topic) first, since it is also related to
your first question (topic) about 3 point landings.

Wheel barrowing (also known as porpoising) is a phenomenon which can occur
when you land flat, or on the nose wheel first, in tricycle gear aircraft.
It happens, I've seen it performed perfectly a few times by student and
non-student pilots. If in fact you saw the pilot do this, then you
witnessed poor pilot technique, regardless of the aircraft he was flying.

Landing flat and especially landing on the nose wheel first is an invitation
to wheel barrow, not to mention that the nose gear is not designed to
withstand the forces generated on it from such a landing. Take a look at
any tricycle gear aircraft and compare the main gear to the nose gear and it
becomes quite obvious as to why you want to land on the mains first.

Wheelbarrowing (porpoising) can quickly damage or destroy an aircraft if not
recovered from immediately. This is but one of the reasons for the 'flare'
you questioned, along with the fact that the flare is also a means of
slowing the aircraft down, thus eventually going from flying speed, to stall
speed, to wont fly anymore hit the ground and roll out speed.

If you look at birds very closely, especially in slow motion video, you will
see that they do indeed flare just before landing. Watch their wings
closely.

A bit of a mention about 3 point landings. Technically there is no such
thing as a 3 point landing in a tricycle gear aircraft. What you saw is
referred to as 'landing flat or a flat landing'. A 3 point landing is when
referring to a tail wheel aircraft that lands on the mains and tail
simultaneously, or even the mains and then the tail touches a second later.

Now on to your second post. "3 more questions"

1. A crosswind is a crosswind, regardless of whether you are taking off or
landing. The wind is still coming from 'across' the runway rather than
straight down the runway. The procedure 'simplified' is apply whatever
rudder is required to keep the nose pointed straight down the centerline,
with ailerons deflected into the wind. As speed increases it will require
less and less rudder and aileron.

2. If you 'tilt' the wing too much you certain can, and pilots have had
engine strikes. But it takes quite an impressive bank to do so. If it
requires that much of a 'tilt' or bank, then what that is telling you is
that the crosswind is too much for that aircraft in it's current
configuration. The same can be said for not having enough rudder to keep
the nose going straight down the runway. If it's a really significant
crosswind, then it's much easier for the novice to discern that it really
does require a combination of both rudder and aileron to land.

3. You slip the aircraft by cross controlling. i.e opposite rudder and
aileron. I sudden draft, or gust, can blow an aircraft a 'off-center'
regardless of whether they are slipping or not. It's just a matter of
experience, training and anticipating and then going around if you don't
like what you're seeing. Every pilot on this form has different thresholds
as to what type of winds and gust are acceptable to them, and what type of
sight picture they're comfortable with before they tuck tail and perform a
go around.

Hope that answered your questions appropriately in my half asleep state.
But heck, that's how I fly half the time anyway.

PJ

============================================
Here's to the duck who swam a lake and never lost a feather,
May sometime another year, we all be back together.
JJW
============================================

"Ramapriya" wrote in message
ups.com...
Has anyone seen wheelbarrowing occur? Prima facie, it appears too
improbable (ludicrous almost) a thing to happen but even the FAA
Airplane Flying Handbook copy that I have mentions it!

Also, while the ways of performing a flare is mentioned at many places,
the reason for a flare is conspicuously absent everywhere. Just why is
a flare needed vis-a-vis a 3-point landing? After all, birds just come
in and sit, without having to flare...

Ramapriya

I've never seen a bird land without flaring. Don't know where you got that,
but they most certainly do flare.

I used to have an ultralight and when I was fast taxi testing it, I noticed
that the back wheels got light first. It turned out it was somewhat out of
rig, but there was really nothing I could do about it. Once I got sort of
good in the thing, I used to let the back wheels come up on takeoff and
rolla long on the nosewheel for a while until it would catch a little bump
and then I'd pull the nose up. Not reall a wise thing to do, in retrospect,
but it was fun and got a lot of looks from whoever might be watching.

Also did a fairly nasty (no damage-but embarassing) late roundout in my
Tripacer once. It resulted in a pretty good bounce which I had to correct
with power for a good landing. They can get ugly quick if you don't react
right or, preferably, just go around and try again.

mike regish
"Ramapriya" wrote in message
ups.com...
Has anyone seen wheelbarrowing occur? Prima facie, it appears too
improbable (ludicrous almost) a thing to happen but even the FAA
Airplane Flying Handbook copy that I have mentions it!

Also, while the ways of performing a flare is mentioned at many places,
the reason for a flare is conspicuously absent everywhere. Just why is
a flare needed vis-a-vis a 3-point landing? After all, birds just come
in and sit, without having to flare...

Ramapriya

A student busted one of our 150s years ago by wheelbarrowing it. He'd
tried to land twice before, both times too fast and high, and had to go
around. This time he was going to land no matter what, and that's when
it happened.
A good landing starts on downwind. Get the airplane properly
positioned, at the right speed and glidepath, start the roundout when
still out of ground effect to prevent floating from excessive speed,
and touch down on the mains with the nose high. Not as easy as it
sounds.

Dan

In article . com, Ramapriya wrote:
Has anyone seen wheelbarrowing occur? Prima facie, it appears too
improbable (ludicrous almost) a thing to happen but even the FAA
Airplane Flying Handbook copy that I have mentions it!

Haven't seen it myself, but it does happen. It's a result of trying to
force the airplane onto the runway before it's ready. The nose winds
up touching down first.

This is bad for several reasons. One of which is that the nose is
ahead of the plane's center of gravity, making it directionally
unstable. One result of which is the infamous ground loop.

Tailwheel airplanes have the same CG/stability issues, so when
you hear about ground loops, it's usually associated with them.


Also, while the ways of performing a flare is mentioned at many places,
the reason for a flare is conspicuously absent everywhere. Just why is
a flare needed vis-a-vis a 3-point landing? After all, birds just come
in and sit, without having to flare...

You don't spend much time watching birds, do you? They do flare.

It's not that there's an rule requiring airplanes to flare, it just
falls out naturally as you transition from a gliding descent into
level flight just above the runway. The idea is to touch down
onto the runway at very little (almost zero) sink rate.

HTH,

Morris

"PJ Hunt" wrote

I'll answer your last question (topic) first, since it is also related
to your first question (topic) about 3 point landings.

PJ, note that Ramapriya's questions deal primarily with jet transports.

Wheel barrowing (also known as porpoising)

Wheel-barrowing and porpoising are NOT the same. Wheel-barrowing always
results from a too-high speed on the ground and the airpane's attitude
remains relatively stable in a nose too-low attitude. Porpoising results
from landing on the nose wheel in a nose-low attitude resulting in the
airplane rebounding into a nose-high attitude and then repeating this
"porpoising" maneuver. Wheel-barrowing can also occur during takeoff
when one attempts to hold the airplane on the ground after normal take-
off speed.


2. If you 'tilt' the wing too much you certain can, and pilots have
had engine strikes.

Jetliner takeoff wings-level to avoid this situation.

The same can be said for not having enough rudder to keep the nose
going straight down the runway.

That's what the nose-wheel steering is for.

3. You slip the aircraft by cross controlling.

Never done in jetliners...too uncomfortable for the passengers.

Bob Moore
CFI ATP B-707 B-727

"Ramapriya" wrote

Also, while the ways of performing a flare is mentioned at many places,
the reason for a flare is conspicuously absent everywhere. Just why is
a flare needed vis-a-vis a 3-point landing? After all, birds just come
in and sit, without having to flare...

The flare reduces the rate of descent for a smooth touchdown. Normal
rate of descent during approach is probably 500-800 fpm and one would
really like to touchdown at less than 100fpm. Of course, the flare
also keeps one from putting too much stress on the relatively weaker
nosewheel.

Note that jets landing on an aircraft carrier do not flare.

Bob Moore

On 25 Dec 2004 02:00:24 -0800, "Ramapriya" wrote:

Has anyone seen wheelbarrowing occur? Prima facie, it appears too
improbable (ludicrous almost) a thing to happen but even the FAA
Airplane Flying Handbook copy that I have mentions it!

Saw one today by someone who was obviously uncomfortable in their new
Bonanza.

z

Ramapriya wrote:

Has anyone seen wheelbarrowing occur? Prima facie, it appears too
improbable (ludicrous almost) a thing to happen but even the FAA
Airplane Flying Handbook copy that I have mentions it!

I've seen it at least twice. The worst case was a Cessna trying to get in before
the field closed for the Sussex County Airshow. The nosewheel hit first and
bounced. Then the mains hit and bounced. The nosewheel came down again, harder.
The plane started porpoising. The third time the nosewheel hit, the tire was
nearly flattened. The noise was impressive. He managed to keep it down on the
fourth strike -- I think the plane had just given up trying to fly by that time.

Also, while the ways of performing a flare is mentioned at many places,
the reason for a flare is conspicuously absent everywhere. Just why is
a flare needed vis-a-vis a 3-point landing?

Typically, the nosegear is more delicate than the mains. The steering mechanism
also may give trouble at high speeds (shimmy is a problem with many designs).
The general idea is to keep the nosewheel off the ground until you're sure there
won't be a problem.

It's also true that the consequences of "wheelbarrowing" can be severe. If the
nosewheel touches before the mains, the back end of the plane continues down
until the mains hit. Once the mains hit, the back end stops traveling down, but
the plane continues to rotate, and the nose wheel leaves the ground again.
Over-reaction by the pilot may cause the nosewheel to come back down even
harder. There have been cases of prop strikes, flattened tires, loss of
directional control, and even cases in which the nosegear broke off. And doing
it in front a a thousand people or so is embarrassing. Flaring properly is an
excellent way of ensuring that this never happens to you.

George Patterson
The desire for safety stands against every great and noble enterprise.

In article , Bob Moore wrote:
"Ramapriya" wrote

Note that jets landing on an aircraft carrier do not flare.

Jets do not land on carriers. They make controlled crashes.


Morris (yeah, old joke, but someone had to say it)