----- Original Message -----
From: "Kingsley Hurst" <hurstkr@growzone.com.au>
Subject: Re: Europa-List: wheel landings
<hurstkr@growzone.com.au>
|
| > BUT the answer to the monwheel Europa is that it should be landed on the
| > stall, so that the she's not flying when you touch.|
| Hello Ferg and others,|
| With the sum total of a couple of landings in a mono, I speak from
| observation rather than experience.|
| When people talk about stalling the mono on landing (the ideal thing to do
| IMHO), I cannot help but wonder how the mono CAN stall unless the tail
wheel | only is on the ground and the main wheel considerably above. My
reasoning | is that because the deck angle of the fuse (with main and tail
wheels on the
| ground) is around 7 degrees from memory. (too lazy to check the manual at
| the moment) and the wing incidence is 2.5 degrees, this means the angle of
| attack of the wings with both wheels on the ground is around 9.5 degrees.
| If I remember correctly, a wing stalls with an AOA of around 14 degrees.
| Considering that when landing the wing is also in the influence of 'ground
| effect', can somebody explain to me how the wing can possibly properly
stall | with such a low AOA ? Cheers Kingsley
KH:
I guess several others answered for me. I believe if you learn
to master this machine, you will be able to fly the length of the runway
with power and only the tailwheel aground. We used to do this with Otters at
airshows.
My mistake was in speaking of absolutes. Landing is some
science, much art so my purpose was to infuse a 'feeling' for what is
happening during approach and landing. None of us has ever done this first
time out - it takes perserverence and dedication. Nevertheless, once
acquired it stays with you and every landing after that adds to the
appreciation.
Both Patrick and Jim answered your question which was not
frivilous because when the tailwheel hits, it pitches the craft forward and
down which does indeed reduce the AoA. However during this exercise, the
speed is falling below that necessary for sufficient lift and the aircraft
flops down where no amount of noseup pressure will resurrect flight. The
advantage is in knowing when this occurs, because there is a speed at which
the stab will have sufficient authority to lift the wings against the
tailwheel. You should be well below that to start with. This brings up gusts
which is another skill altogether.
As several others will attest, big 'planes carry 'way' (a marine
term for momentum) and so when a gust arrives, the first thing that happens
is the airspeed rises accordingly. This can ruin your day if the gust
reduces headwind because the airspeed jumps below stall. The 'big guys' take
half the value of a gust and add it to the approach speed, thus reducing the
risk by half (on average). Of course they never subtract 1/2 the gust for
obvious reasons.
BUT in a small a/c (like the Euro or Moth) you're leaf in the
wind. The machine is up with a headgust, down with a loss of gust. Because
the Euro is so slick, extra speed translates into late landing. All this
should be going through the gray stuuf as you approach. Lightplane drivers
will confirm that they have learned to sniff the wind, look for signs, watch
the windsock. Really, big machine aviators should too but for other reasons.
I'm sure you find the Air France chap in Toronto was suckered into
continuing because he was not told of a lowlevel wind component - perhaps
indetected - and you can bet your boots the insurance lawyers won't bring it
up. At many US fields, lowlevel wind sensors reveal previously-unrecognised
outflow winds from nearby cu-nims. To absolve aviators of faulty charges
they should be available everywhere. Until then, a healthy respect for the
50foot wind is priceless and no less true with light aircraft.
Jim and the others will probably tell you their noses are
sniffing the wind vector out every ten seconds, until they don't even
realise it - it's like riding a bike - it becomes instinctive. You read the
wind from all these inputs during an approach, (from first contact if by
radio to 20 or 30 feet above the ground) and you'll never be surprised.
Another thing: This is often missed during checkout, but a
quick, short burst of power will often straighten out an impending swerve.
Yes, it can tend to add speed, but it's first effect is to pull the machine
straight ahead. Got to be short, mind you. Try it out in the air to see if a
swift burst doesn't work on occasion. It sure works with a Stearman or
Harvard. The other advantage is, if it doesn't have the desired effect -
you're on your way to a Go Around earlier. Naturally this applies only to
tractors!
I'll shut up now.
Ferg
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