Pitot Blockage

The Pito in my Twin Astir is blocked.
The glider was stored for 6 monthes. Perfect befor - totaly blocked
after.
The blockage is between rear seat to the tail.
I'v tried to blow / suck as hard as can without any air movments.
It is imposible to insert a wire from the pito at the tail - probbaly a
90 degree connection inside.
Trying to push a 3/32 cable into the tube, it gets harder after 4 feet
because the vinyl tube is sticky and a lot of friction.

Any ideas?

Maybe a small animel crowled inside and died and now is swallen.
Should I send ants inside ? ;-

Avron Tal

We had the same problem this spring with our twin when a few bees
dcided to crawl into the pitot tube. We ended up having to take the
rudder off to disconnect the tubing and then we could free the blockage
of bee and nest with a piece of wire. It was a real pain and took a
few hours to complete the repair, but it was the only way...after we
tried a couple hours of what you described above

Adam

Hi Adam,

Is there access from the ruddder into tail and to the tube/pito
connection?
I take it from your letter that removing the rudder will let me
disconnect the tube inside the tail without cutting holes in the
fiberglass.

Avron

Yes, on our club's Twin Astir we can access the back of the pitot tube
by removing the rudder and then using a pair of forceps, or a small
hand, to disconnect it. Once we had the rubber tube disconnected, then
we could clean out the blockage with a piece of heavy gauge safety
wire, and blow it out from the instrument side (make sure you
disconnect all the instruments before you pressurize the line or you
could cause damage to them). We also have a small filter installed
behind the panel to trap any small particles or water that gets in the
lines. I hope it is as easy for you as it was for us. You may be able
to do it without removing the rudder if you find a good stiff single
strand wire that is flexible enough to make the bend in the tail and
then blow it out from the front.

Adam

Hi,

Of course you will want to be careful so that any debris that is knocked
loose does not blow into your airspeed indicator or speed-to-fly variometer.

Is the pitot mounted in the nose or tail?

I would recommend removing the tubing and replacing it if possible - for the
reason mentioned above.

I would try varios rods and pipe cleaners. Spraying silicone lubricant onto
the rod or cleaner may help it slide inside the tube.

I sell small filters that could be used to keep debris out of your
instruments. You would install close to the instruments - downstream of
the blockage. They are quite inexpensive.
http://www.soarmn.com/cumulus/ilec.htm#AirFilter

Paul Remde
Cumulus Soaring, Inc.
http://www.cumulus-soaring.com

"Avron" wrote in message
oups.com...
The Pito in my Twin Astir is blocked.
The glider was stored for 6 monthes. Perfect befor - totaly blocked
after.
The blockage is between rear seat to the tail.
I'v tried to blow / suck as hard as can without any air movments.
It is imposible to insert a wire from the pito at the tail - probbaly a
90 degree connection inside.
Trying to push a 3/32 cable into the tube, it gets harder after 4 feet
because the vinyl tube is sticky and a lot of friction.

Any ideas?

Maybe a small animel crowled inside and died and now is swallen.
Should I send ants inside ? ;-

Avron Tal

And the motto of this story is=20
Ask your self why the RAF etc have pretty little things flapping in the =
breeze that say Remove Before Flight=20
and buy yourself a Pitot head cover and Use it=20
I got mine from LAS Aero here in the UK wasn't expensive=20
So I'll be Flying on Sat or Supping tea in the clubhouse enjoy your =
repair !!!

And the motto of this story is Ask yourself why the RAF have pretty =
little things flapping in the breeze that say Remove Before Flight and =
buy yourself a Pitot head cover and use It they are not Expensive From =
LAS Aero

Hook up a compressed air tank to the tubing to blow out the tubing. Just
make sure ALL your instruments are disconnected beforehand!

"Avron" wrote in message
oups.com...
The Pito in my Twin Astir is blocked.
The glider was stored for 6 monthes. Perfect befor - totaly blocked
after.
The blockage is between rear seat to the tail.
I'v tried to blow / suck as hard as can without any air movments.
It is imposible to insert a wire from the pito at the tail - probbaly a
90 degree connection inside.
Trying to push a 3/32 cable into the tube, it gets harder after 4 feet
because the vinyl tube is sticky and a lot of friction.

Any ideas?

Maybe a small animel crowled inside and died and now is swallen.
Should I send ants inside ? ;-

Avron Tal

Perfect way to blow internal connection apart leadimg to painful
surgery.
This is last resort
UH