Astir CS TE line access

Anyone have any experience with accessing the TE/Pitot line connections in the fin of an Astir CS? Is there anyway to peek at the TE/Pitot lines where the plug into the ports at the back of the tube/ports in the fin? I want to see if the TE line is still attached to the back of the TE prob but can't seem to find anyway to get access to that area.

Also, has anyone ever replaced the TE(or pitot) lines all the way back to the fin in an Astir CS?

On Wed, 05 Feb 2020 19:35:29 -0800, soaringjac wrote:

Anyone have any experience with accessing the TE/Pitot line connections
in the fin of an Astir CS? Is there anyway to peek at the TE/Pitot lines
where the plug into the ports at the back of the tube/ports in the fin?
I want to see if the TE line is still attached to the back of the TE
prob but can't seem to find anyway to get access to that area.

You can check the integrity of those connections easily enough without
looking inside the fin.

Pitot: block the hole by putting your thumb firmly over it and, keeping
your thumb over the hole, wrap your hand firmly round the pitot probe to
warm it up while you or a friend watches the ASI. If the line has no
leaks the ASI reading will come up to 15-20 kts in a few seconds and then
stay steady until you let go of the pitot. The speed of the rise will
depend on how thick the metal is in the pitot probe and the value of the
steady reading depends on how much warmer your hand is than the ambient
air. If the reading peaks and then slowly drops while you're still
holding the pitot you may have a small leak. To repeat the test, let the
pitot cool down for a minute or two and then do it again.

TE: switch on the vario and turn the volume right up. Now put your hands
on each side of the TE probe, about 30-40 mm (1.5-2") apart and blow hard
between them. If there are no leaks you should hear the vario signal a
climb while you're blowing. Mechanical vario? Get a friend to watch it
while you blow.

I use both tests on my Libelle after putting the panel back in to check
that the pneumatic multi-connector is seated correctly and not leaking. I
can easily see the ASI (at the top centre of my panel) and hear the vario
with the canopy off but whether you can see your ASI may depend on where
it is in your panel and how high the Astir's rear cockpit rim is.

Also, has anyone ever replaced the TE(or pitot) lines all the way back
to the fin in an Astir CS?

Nope, never had to do that. If its anything like my glider, that will
involve cutting holes in the fin.


--
Martin | martin at
Gregorie | gregorie dot org

On Wednesday, February 5, 2020 at 7:35:31 PM UTC-8, soaringjac wrote:
Anyone have any experience with accessing the TE/Pitot line connections in the fin of an Astir CS? Is there anyway to peek at the TE/Pitot lines where the plug into the ports at the back of the tube/ports in the fin? I want to see if the TE line is still attached to the back of the TE prob but can't seem to find anyway to get access to that area.

Also, has anyone ever replaced the TE(or pitot) lines all the way back to the fin in an Astir CS?

Our club has a AStir CS and over the years we have problems with maintenance items on the TE and Pitot port in the vertical stabilizer. You can see the connections after taking off the horizontal stabilizer and use a flashlight. I found it is much easier to see at night or under a blanket in the day time. One of the biggest problems we have had was people were inserting the TE probe to far causing the tubing to push off the connector at the back.. Not all probes might not be like ours and allow this to happen, a poor design. Another is both the TE and Pitot port are the same inside diameter and more than once someone has inserted the TE in the pitot port. Needless to say the airspeed was crazy. Another really poor design feature.

Far as testing for leaks, I learned a trick from a local mechanic. Block off the lines at one end and suck on the other end. You can add extra tubing you are OK with putting in your mouth. Afte sucking, put you tongue on the end and see how long it hold a vacuum. A good system will not lose any suction for as long as you care to keep your tongue on the end.

We have never replaced the lines, but I would guess if it is possible, you will need to use the old line to pull new one through. Join the new and old with a good barbed fitting and be careful and patient. Lubing the line might help. Getting it wrong and you might be in for some rather cost repairs.

Hope this helps. IF you have a leak, I hope it will be at the end points and not need to replace the lines. That could be very risking. IN general the static plumbing in the CS is the craziest with 5 ports. 4 static in 2 pairs and one TE.

Buzz Graves

On Thursday, February 6, 2020 at 8:00:10 AM UTC-8, BG wrote:
On Wednesday, February 5, 2020 at 7:35:31 PM UTC-8, soaringjac wrote:
Anyone have any experience with accessing the TE/Pitot line connections in the fin of an Astir CS? Is there anyway to peek at the TE/Pitot lines where the plug into the ports at the back of the tube/ports in the fin? I want to see if the TE line is still attached to the back of the TE prob but can't seem to find anyway to get access to that area.

Also, has anyone ever replaced the TE(or pitot) lines all the way back to the fin in an Astir CS?

Our club has a AStir CS and over the years we have problems with maintenance items on the TE and Pitot port in the vertical stabilizer. You can see the connections after taking off the horizontal stabilizer and use a flashlight. I found it is much easier to see at night or under a blanket in the day time. One of the biggest problems we have had was people were inserting the TE probe to far causing the tubing to push off the connector at the back. Not all probes might not be like ours and allow this to happen, a poor design. Another is both the TE and Pitot port are the same inside diameter and more than once someone has inserted the TE in the pitot port. Needless to say the airspeed was crazy. Another really poor design feature.

Far as testing for leaks, I learned a trick from a local mechanic. Block off the lines at one end and suck on the other end. You can add extra tubing you are OK with putting in your mouth. Afte sucking, put you tongue on the end and see how long it hold a vacuum. A good system will not lose any suction for as long as you care to keep your tongue on the end.

We have never replaced the lines, but I would guess if it is possible, you will need to use the old line to pull new one through. Join the new and old with a good barbed fitting and be careful and patient. Lubing the line might help. Getting it wrong and you might be in for some rather cost repairs.

Hope this helps. IF you have a leak, I hope it will be at the end points and not need to replace the lines. That could be very risking. IN general the static plumbing in the CS is the craziest with 5 ports. 4 static in 2 pairs and one TE.

Buzz Graves

Thanks Buzz, great info. Can you get your hands on the connections in the fin at all with the horizontal off? Im going to take the horizontal off this weekend so i guess we will see. I am also going to do a bit of leak testing as well. Just trying to figure out what options i have and what i have access too. Ideally i would like to just replace the lines and have everything fresh, but yeah that seems risky. Hoping its something simple and easy. Maybe the old winter vario i have in there has a leak in its casing or something. I put in a new flask and all new lines forward of the wheel so everything is new, connections seem great, but leak testing will tell. I was getting these stick thermals before i replaced the lines so that is what is making me think its something rearward of the wheel.

Ah, yes. Inserting your probe in too far can be a huge problem for some, and not so much for others, eh?

Boggs