[Kato's 8]

Afternoon!
Could some one help me with a decision please. I was plumbing the static line to the various gages in panel. Basic set up is: Static line to a Safe air manifold, then branch off to the Alt, the ASI, the VSI, and the encoder. All from the manifold. Its a simple and clean way to do it but now I realize I dont know where the test equipment is to be tied in during the biennial transponder check.
Sooo... Should I add a t-fitting before the manifold and pug the unused port to tie in there or should I tee in AFTER the manifold and do same thing? Does it matter?
What is done when they tie in? I assume they pressurize and test for leaks maybe?
Why is transponder turned on during test? Do they pressurize to say 1000 feet AGL and then check transponder signal or something?
Basicly need a transponder/static sys check for dummies explanation and how I can make my system easily accesable later.
Its VFR and encoder is simple ameriking.
Thanks guys!
Bill

 

[longranger]

When I've been there while my 170 was being done, they use the static port on the outside of the airplane. No breaking in to the system; no need to provide a test port.

Transponder and altimeter get tested to 20000 ft (I think in 2000 ft increments??).

 

[Mike S]

I just had my xpnder check this week, and it was done with only a electronic gadget that sat on a tripod next to the plane. No actual physical contact with the plane at all.

The tech said that for a VAF certification, there was no need to check the static or pitot system.

 

[longranger]

I just had my xpnder check this week, and it was done with only a electronic gadget that sat on a tripod next to the plane. No actual physical contact with the plane at all.

The tech said that for a VAF certification, there was no need to check the static or pitot system.

How can you gauge the accuracy of your encoder without applying the various altitudes to the static system???

 

[Walt]

Rather than doing a bunch of copy and pasting, check my FAQ page on my website, I think it should answer all your questions, if not please let me know.

http://www.expaircraft.com/faq.htm

 

[Mike S]

How can you gauge the accuracy of your encoder without applying the various altitudes to the static system???

Set the EFIS to 29.92". The encoder is in the EFIS. This may not work for steam panels with separate encoders??

 

[longranger]

Set the EFIS to 29.92". The encoder is in the EFIS. This may not work for steam panels with separate encoders??

Still, you've got to change the pressure physically applied to the static system somehow, no matter where the encoder is.

 

[Mike S]

Miles, I have no idea what is needed, I only followed the instructions the guy with the license gave me.

 

[Walt]

An easily accessible test port on RV's can be a handy thing, sometimes my equipment has trouble sealing on the 'rivet' static port.

 

[longranger]

You can do a transponder-only check (does it receive interrogations and reply properly) without connecting to the airplane, but you HAVE to connect to the static system to check encoder accuracy.

 

[Mike S]

 

[Walt]

Due every 24 months.

VFR check reqmnts: Transponder only.

IFR check reqmnts: Transponder, altimeter, encoder (matches altimeter), static system.

 

[Kato's 8]

Ok so what I gather, since its VFR, I just need to turn on transponder and the check can be done w/o touching it? I've had this check done for VFR only citabria and the licensed person hooks something up but don't know what. He waits for transponder to start functioning after a warm up and then he's done. I was told he only needs to hook into antenna but no one here mentioned that so I question the antenna answer
I also heard you say the rivet is good access if I should decide to check system even though not required and an access port would be nice if rivets are not sealing.
Do I need to check static system and altimeter and encoder to altimeter match on the initial inspection since its a new build? Or is the plain ole transponder check all that's required?
Thanks for your help! I understand better now

 

[gasman]

Confused!!

I just had my xpnder check this week, and it was done with only a electronic gadget that sat on a tripod next to the plane. No actual physical contact with the plane at all.

The tech said that for a VAF certification, there was no need to check the static or pitot system.

What is a VAF certification?

 

[Walt]

Ok so what I gather, since its VFR, I just need to turn on transponder and the check can be done w/o touching it? I've had this check done for VFR only citabria and the licensed person hooks something up but don't know what. He waits for transponder to start functioning after a warm up and then he's done. I was told he only needs to hook into antenna but no one here mentioned that so I question the antenna answer
I also heard you say the rivet is good access if I should decide to check system even though not required and an access port would be nice if rivets are not sealing.
Do I need to check static system and altimeter and encoder to altimeter match on the initial inspection since its a new build? Or is the plain ole transponder check all that's required?
Thanks for your help! I understand better now

Normally the antenna is not disconnected, a directional antenna is aimed at your transponder antenna to take the measurements.

You don't "need" a static system check unless its for an IFR cert, but its usually a good idea so you have a leak free system.

For new certifications or if the encoder or altimeter has been replaced, a Data Correspondence Check must be accomplished to ensure the altitude data transmitted to ATC corresponds to within 125 feet of the altimeter normally used to maintain flight altitude (per CFR 91.217).

If you have a "glass" panel and the altitude data from it supplies the transponder then it will always match, if you have a seperate altimeter/encoder then it must be checked.