Pitot static drain access

[Mooneymite]

I had my pitot static check done today.  A fellow comes to my hangar and does the whole thing and he's very thorough even though he is not a "Mooney guy".  It's very convenient.

Today I asked him to check the pitot and static drains.  He quickly found and cleaned the static drain, but he was flumoxed on the pitot drain.  After pointing it out, he said, we were taking a chance messing with it because if it had to be replaced, there was no way to access it.

I assured him that it could be accessed either from the wing root fairing, or from the small access panel beneath the wing.  I was wrong.

After removing both the fairing and the access cover, we agreed that the airplane must have been built around that darn drain.

Does anyone know how to access the drain should it ever need to be replace?  ('74 C Model.)

• The first picture shows the drain near the lower left wing root....
• The second picture is the amount of room removing the wing fairing allows...even skinny fingers would have a problem getting in there....
• The third picture shows the lower access panel removed.  No help since there is a rib between the panel and the drain valve.
• The fourth picture is the drain valve which can only be seen with a mini cam on a wire.  Picture taken from above through that small space under the wing fairing.

[madjano]

Seems like you could get to it by removing the interior panel, but i have never specifically looked.

[Marauder]

I had my pitot static check done today.  A fellow comes to my hangar and does the whole thing and he's very thorough even though he is not a "Mooney guy".  It's very convenient.

Today I asked him to check the pitot and static drains.  He quickly found and cleaned the static drain, but he was flumoxed on the pitot drain.  After pointing it out, he said, we were taking a chance messing with it because if it had to be replaced, there was no way to access it.

I assured him that it could be accessed either from the wing root fairing, or from the small access panel beneath the wing.  I was wrong.

After removing both the fairing and the access cover, we agreed that the airplane must have been built around that darn drain.

Does anyone know how to access the drain should it ever need to be replace?  ('74 C Model.)

• The first picture shows the drain near the lower left wing root....
• The second picture is the amount of room removing the wing fairing allows...even skinny fingers would have a problem getting in there....
• The third picture shows the lower access panel removed.  No help since there is a rib between the panel and the drain valve.
• The fourth picture is the drain valve which can only be seen with a mini cam on a wire.  Picture taken from above through that small space under the wing fairing.

 

It is the most inaccessible component on the Mooney. I was going to replace mine when I did the static drain. Once I saw its location, I called uncle. I think it is the same drain as the static.

 

 

Sent from my iPad using Tapatalk Pro

[Mooneymite]

Let me think....

If the pitot drain leaks, the indicated airspeed will read low, right?

That's it!

The pitot drain is leaking and my Mooney is MUCH faster than I thought.  It's affecting my GPS groundspeed and my clock as well.

[Guest]

You have to remove the interior side panel to access the valve.  It can be repaired by unscrewing the two lines, then unscrewing the “T” fitting, then removing the spring, plunger( which is an AN Clevis pin) and the “O” ring.

Reassembly is equally challenging.

Clarence

[Mooneymite]

1 minute ago, M20Doc said:

You have to remove the interior side panel to access the valve.  It can be repaired by unscrewing the two lines, then unscrewing the “T” fitting, then removing the spring, plunger( which is an AN Clevis pin) and the “O” ring.

Reassembly is equally challenging.

Clarence

Ah!  So you access it from INSIDE the cabin????

I thoight about that, but it looked like the opening was filled with wires and tubes.

Thanks!

Here's hoping I never have to verify this.  

[Guest]

1 minute ago, Mooneymite said:

Ah!  So you access it from INSIDE the cabin????

I thoight about that, but it looked like the opening was filled with wires and tubes.

Thanks!

Here's hoping I never have to verify this.  

You could hire a proctologist to do this for you, it’s very similar work.

Clarence

[bradp]

That wing root access is right tight and there’s a ton of sharp $hit protruding into and around it, never mind the wiring bundle and plumbing that takes up more space.  

[RobertGary1]

I just removed the interior panel and used a couple different wrenches to unscrew it from the housing and replaced the seal.  Rarely necessary to do more than change the seal and clean with denaturalized alcohol  

-Robert

[RobertGary1]

I took this when I changed the seal in mine. I was laying where the pilot seat would be. 

[Mooneymite]

1 hour ago, RobertGary1 said:

I took this when I changed the seal in mine. I was laying where the pilot seat would be. 

Looks like you were upside down!

Thanks for posting.   At least now I know it can be done.  I passed the info along to the pitot static guy.  His comeback was.... "don't fix what ain't broke".

[RobertGary1]

1 hour ago, Mooneymite said:

Looks like you were upside down!

Thanks for posting.   At least now I know it can be done.  I passed the info along to the pitot static guy.  His comeback was.... "don't fix what ain't broke".

For sure. If he's not showing it leaking I wouldn't touch it.

 

-Robert