landing on water

Publié le par Juliette

 

 

 

http://acro.harvard.edu/MITSA/news_letters...2/news9902.html 



"Landing on water: Over the years, there has been an on-going debate on whether
it is better to land gear up or gear down on water. Current thought from Tom Knauff
is to always land gear down. The rationale is that a water landing with gear up will
result in the tail touching down first with the tail being sucked into the water. This in
turn results in the nose pitching up and a higher angle of attack for the wings. Given
the higher angle of attack, the glider then shoots back into the air until it stalls. Upon
stalling, the nose drops down and dives steeply into the water. Put the gear down in
a water landing and try to keep the tail from dropping. Dropping the gear also results
in increasing water resistance, which further slows down the ship. Another water l
anding aspect Tom relayed is that one always wants to land close to and parallel to
the shoreline, but not so close as to hit the bottom in the event something goes
wrong during the landing. You will want to maintain good aileron control for as long as
possible. You do not want one of the wing tips hitting the water first at a high speed
as the glider may flip. Once the glider has settled to a stop, it may float for awhile.
I once saw a PIK that had been taken off the bottom of a lake and restored.
This one flew better than it floated. "

 

 

He lined up parallel to the
shore line about 50 ft. out. He had some flap in and the
gear down, and
was using the dive brakes. He did a short field type of
approach with the tail skimming the water. When the wheel
dug in the
fun began. Hank said the water came over the canopy
with a big whoosh, and by the time it cleared water was
rising fast in
the cockpit. Hank felt some real urgency to get out as
the water came up to mid-chest. He released the belts and
chute.
About that time the plane stopped sinking. The buoyancy
of the wings was slowing the descent to the bottom. Hank
got out
in water over his head and started swimming and
dragging things to the shore. Two fisherman were on shore
and helped get
the plane close to shore but by this time it was a real
imitation of the Titanic. He did get it shore enough to
keep the nose
above water but the rest was down and full.

The retrieve got the call with Hank giving a brief
recount of the landing and telling them he had no idea
where he was
because the GPS was underwater and not working. Pepe
Sayer, and several locals packed up the trailer and
headed south.
Getting the plane out of the water was quite a chore as
it was very heavy. The guys chose to work in their
underwear and
have dry clothes for the trip home. Admiral Nixon as he
was now known did not have this dry clothes option.

Hank talked about the incident at this morning's pilot
meeting. Hank took a lot of ribbing with jokes about
being overweight at
the grid, to replacing his GPS with a fishfinder. I am
just glad he was standing before us to take it. The plane
was damaged.
Hank said that if he had it to do over again he would
not have used the dive brakes. When the water went over
the wings it
folded both brakes back and put enough stress on the
left wing to crush it at the aft root. The flaps were
also slightly
damaged but Hank said he would have used them no matter
what.

We were hoping that the high cu's we saw yesterday on
the plateau would be over us today. Overnight, very dry
Canadian air
moved down over us and dried out the whole task
area....

 

 

 

 

 

 

 

 

 

 

 

 

 

Commenter cet article

ucak bileti 03/08/2016 03:53

thank you by admin