Hmmm! 
You touch on an interesting point here when you say "....landed wheel down
trying to put them up the beach."

It seems quite obvious to me that just like paddock landings, no two water
outlandings are exactly the same; every water landing has its own
peculiarities, and hazards.

Whilst it might seem obvious, let me definitively state here, that in the
first instance, a water landing should be avoided at all costs!

Here are a few scenarios to consider, and no doubt there are many more:
 Landing in open waters - the sea, or a very large lake - Here wind and wave
action will be present, How are you going to deal with this? As far as I
can determine, nobody has seriously looked at this scenario. YouTube has
some fascinating footage of a T21? landing in relatively smooth seas. Quite
obviously, this ship has a fixed wheel, so the gear-up, gear-down option
does not apply. Also of interest here is the actual landing speed of the
glider. I am prepared to take bets, but it is very obvious that this glider
"lands" at a speed of about half the landing speed of a modern composite
fibre glass glider. Great landing. A question of interest is "What happened
next?"[Quite obviously it did not instantly sink.]  
 Landing close to an ocean-facing ridge/cliff. There may or may not be a
landing option. In the latter case this is generally defined as a crash if
things go pear-shaped!
 Landing in a relatively small lake, without much wave action ie relatively
smooth surface. 
 Landing in a river/canal: Ditto the above.

The last two scenarios seem to be the focus of the current thread, but as I
have pointed out above, THERE IS MUCH MORE TO CONSIDER!

Let me make a few comments, starting with the first line quote above. If
there is a beach, why not land on it - you do not have to "head" towards it.
Cath Conway has summarised  the situation, regarding what the manufactures'
recommend: Yes, it is very simple - land wheel down. Mike Borgelt has
pointed you towards some theory to consider as to just why you should do
this. In the lake scenario (without beaches), ALWAYS land parallel to the
shore, with say about 2 m of water under your keel - if you can judge this.
This will max out your chances if your glider decides to become a submarine.

In your post there is another point, that I think needs further discussion -
video evidence shows that the glider does not necessarily "RAPIDLY" sink as
you stated. It seems to me that in the instance presented, the glider is
happily floating along and is very far from sinking. Get your horse before
the cart. When the electrics/electronics are submersed, kiss them goodbye.
Here is another thought: After running the video of the water landing in
question a few times, it is very apparent that the video quality is of such
poor quality, that it is impossible to determine if the wheel is up or down.
Most posts seem to assume the wheel is up. In my opinion, highly unlikely if
we believe the theory ... which I do.        

Just why pilots get into the situation where they might experience one of
these scenarios is I think endlessly fascinating, but any discussion on this
is I think the possible start of a whole new (and possibly most
interesting), thread. Who want to start it?

Gary  



 

-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of DMcD
Sent: Saturday, 30 August 2014 3:53 PM
To: Discussion of issues relating to Soaring in Australia.
Subject: Re: [Aus-soaring] Water Landing

Sent to me in 2008:

Tests were carried out on a lake in Germany by Walter Schneider and
Wolf Lemke of LS fame. They ditched an LS1 prior to the World
Championships in Finland because they were worried about the lack of
land out options and the proliferation of lakes.

They assumed that landing wheel up would be the preferred option, but
discovered that the glider 'bounced' off the surface and dropped a
wing as the fuselage entered the water because of it's shape. They
tried it again with the wheel down, deliberately put the tail down
first and discovered that the wheel acted as a gentle brake and
controlled the whole process much better. I've seen the photographs,
so they may be available on some German web site somewhere.

During the Worlds in Borlenge Sweden, a couple of gliders were put
into lakes and all came out okay. I'm pretty certain they landed wheel
down trying to put them up the beach. The major issue with such
landings is that the glider sinks VERY quickly (regardless of wheel
position) and the electrics can cause problems as you'd expect. It's
certainly not recommended!
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