Pitot/Static/Transponder check

[ScottM]

I just had my first pitot/static/transponder check done and I was wondering what they actually do to see that everything is working correctly and all items are in alignment?

I have noticed that when my altimeter goes about 10 feet past a point, like 5010 the transponder output says 5100 feet. I always think that I am about to get in trouble from ATC when see a deviation of a hundred feet when I have only bounced 10 or 20 feet.

 

[Joe B]

I just had my first pitot/static/transponder check done and I was wondering what they actually do to see that everything is working correctly and all items are in alignment?

They hook a vacuum pump and calibrated gauge up to the static system and start taking readings. Once the system reaches the max certified altitude they close a valve - the system has to "maintain altitude" for a few minutes to make sure it's airtight.

I have noticed that when my altimeter goes about 10 feet past a point, like 5010 the transponder output says 5100 feet. I always think that I am about to get in trouble from ATC when see a deviation of a hundred feet when I have only bounced 10 or 20 feet.

Normal. You've dialed in an altimiter setting, such as 29.42, which happens to be 50' off from the transponder's built-in setting of 29.92. Not to worry - the controller dials the altimiter setting into his/her console which corrects the altitude for all the transponders on the screen. So the controller sees pretty much the same altitude as you see on your altimiter (provided you've dialed in the altimiter setting the controller gave you).

There's one small exception: When the altimiter setting is half-way between hundreds off from 29.92 a small change in your altitude can cause the transponder to jump to the next hundred, as in the example you gave. Controllers know about this and expect it so they don't worry about ±100'

Regards,
Joe

 

[Tom-D]

They hook a vacuum pump and calibrated gauge up to the static system and start taking readings. Once the system reaches the max certified altitude they close a valve - the system has to "maintain altitude" for a few minutes to make sure it's airtight.



Normal. You've dialed in an altimiter setting, such as 29.42, which happens to be 50' off from the transponder's built-in setting of 29.92. Not to worry - the controller dials the altimiter setting into his/her console which corrects the altitude for all the transponders on the screen. So the controller sees pretty much the same altitude as you see on your altimiter (provided you've dialed in the altimiter setting the controller gave you).

There's one small exception: When the altimiter setting is half-way between hundreds off from 29.92 a small change in your altitude can cause the transponder to jump to the next hundred, as in the example you gave. Controllers know about this and expect it so they don't worry about ±100'

Regards,
Joe

Just to add ->

Your Transponder changes the altitude it is sending half way between each 100' --50'----150'----250'---ect. so, if you are at 5010 the transponder will send 5000' and has been since you pased thru 4950, and will go to 5200' at 5050'.

 

[poadeleted20]

BTW, it's an altimeter/static/transponder check; the pitot system is not checked, and there is no requirement to check it.

 

[KennyFlys]

BTW, it's an altimeter/static/transponder check; the pitot system is not checked, and there is no requirement to check it.

For this reason, I discovered my commercial ride DE likes the term "Static System" and does not want to hear "pitot-static system."

 

[Tom-D]

BTW, it's an altimeter/static/transponder check; the pitot system is not checked, and there is no requirement to check it.

Many pople get that confused, the Pitot system is the positive pressure system that drives the airspeed indicator, the static system is the barometric pressure system that drives the altimeter, Mode C and the VSI.

The rule says:
91.411 Altimeter system and altitude reporting equipment tests and inspections.

(a) No person may operate an airplane, or helicopter, in controlled airspace under IFR unless-

(1) Within the preceding 24 calendar months, each static pressure system, each altimeter instrument, and each automatic pressure altitude reporting system has been tested and inspected and found to comply with appendix E of part 43 of this chapter;

those are the plumbingthe altimeterand the Mode C

 

[Tim]

Many pople get that confused, the Pitot system is the positive pressure system that drives the airspeed indicator, the static system is the barometric pressure system that drives the altimeter, Mode C and the VSI.

The rule says:
91.411 Altimeter system and altitude reporting equipment tests and inspections.

(a) No person may operate an airplane, or helicopter, in controlled airspace under IFR unless-

(1) Within the preceding 24 calendar months, each static pressure system, each altimeter instrument, and each automatic pressure altitude reporting system has been tested and inspected and found to comply with appendix E of part 43 of this chapter;

those are the plumbingthe altimeterand the Mode C

Where is the check for VFR? Where you been Tom?

 

[Tom-D]

Where is the check for VFR? Where you been Tom?

I believe that the issue of having or not having the transponder/mode C is a case of how usefull do you want your aircraft to be.

Where are you going to be month of June?

 

[Tim]

I believe that the issue of having or not having the transponder/mode C is a case of how usefull do you want your aircraft to be.

Where are you going to be month of June?

I will be here. My retired brother living in New Mexico is coming up too. Just got my Xpnder checked for 135.00 had it done by a different guy this year.

 

[poadeleted20]

The transponder check requirement for all transponder use whether under IFR or VFR, regardless of controlled or uncontrolled airspace, is in a different regulation -- 14 CFR 91.413. If it isn't checked per 91.413, you aren't allowed to turn it past STBY in a US-registered aircraft.

 

[mikea]

I have personal knowledge because at my last check the Mr. mobile guy found the altimeter case had a leak. I got a VFR-only sign off. I just told the mechanic that if he finds that this time to replace the altimeter.

 

[Tom-D]

I will be here. My retired brother living in New Mexico is coming up too. Just got my Xpnder checked for 135.00 had it done by a different guy this year.

See the web page


http://www.whidbey.com/fairchild-nc19143/id14.htm

 

[Tim]

The transponder check requirement for all transponder use whether under IFR or VFR, regardless of controlled or uncontrolled airspace, is in a different regulation -- 14 CFR 91.413. If it isn't checked per 91.413, you aren't allowed to turn it past STBY in a US-registered aircraft.

The question isn't about weather the transponder needs to be done the question is for VFR where is the requirement and what is the procedure for a VFR only check on the static system? It Ain't Appendix E.

I say it is all in 91.217. 91.411 doesn't apply to VFR only. How ever 91.217 doesn't specificaly state IFR, in the same manner as does 91.413 for the transponder. 91.217 also gives the tolerance and the procedure for the test.

But hey, all I have is a highschool diploma

 

[tonycondon]

The transponder check requirement for all transponder use whether under IFR or VFR, regardless of controlled or uncontrolled airspace, is in a different regulation -- 14 CFR 91.413. If it isn't checked per 91.413, you aren't allowed to turn it past STBY in a US-registered aircraft.

isnt there a reg requiring transponder to be ON if installed? so basically requiring all transponders to be inspected?

 

[Tim]

isnt there a reg requiring transponder to be ON if installed? so basically requiring all transponders to be inspected?

That would be 91.215 Par.c If it was maintained I.A.W. 91.413

 

[poadeleted20]

The question isn't about weather the transponder needs to be done the question is for VFR where is the requirement and what is the procedure for a VFR only check on the static system?

There isn't one. If you don't fly IFR, there is no requirement to check the static system.

 

[poadeleted20]

isnt there a reg requiring transponder to be ON if installed?

No. 91.215 requires your transponder to be turned on any time you're in controlled airspace (Class E or higher) if it is properly inspected IAW 91.413. If it isn't so inspected, you are not allowed to turn it on at all, and then you have to stay out of the transponder-required airspaces listed in 91.215(b) (basically above 10,000 MSL, into Class A/B/C airspace, or into a Mode C veil) unless you get a waiver IAW 91.215(d) to go into some of those areas if your transponder is inop or overdue for inspection.

so basically requiring all transponders to be inspected?

Only if you want to go into 91.215(b)-listed airspace, obtain radar service, or be seen by ATC and TCAS/TPAS/etc-equipped aircraft.

 

[Tim]

There isn't one. If you don't fly IFR, there is no requirement to check the static system.

I wish all the repair stations knew that...........

 

[mikea]

No. 91.215 requires your transponder to be turned on any time you're in controlled airspace (Class E or higher) if it is properly inspected IAW 91.413. If it isn't so inspected, you are not allowed to turn it on at all, and then you have to stay out of the transponder-required airspaces listed in 91.215(b) (basically above 10,000 MSL, into Class A/B/C airspace, or into a Mode C veil) unless you get a waiver IAW 91.215(d) to go into some of those areas if your transponder is inop or overdue for inspection.

Only if you want to go into 91.215(b)-listed airspace, obtain radar service, or be seen by ATC and TCAS/TPAS/etc-equipped aircraft.

There isn't one. If you don't fly IFR, there is no requirement to check the static system.

So the "VFR approval" means the transponder has been inspected, but the static system hasn't? That's what my A&P, and the mobile check guy, and I assumed.

 

[poadeleted20]

So the "VFR approval" means the transponder has been inspected, but the static system hasn't?

There is no FAA definition of the term "VFR approval," so I guess it means whatever the shop says it means. However, a reading of the log entry should tell you which tests were done -- the transponder test per 91.413, the altimeter/static test per 91.411, both, or neither. You need both for IFR flying, the transponder test for VFR flying, and neither if you don't go anywhere you need a transponder.

That's what my A&P, and the mobile check guy, and I assumed.

I'm not a real big fan of "assumed."

 

[MBDiagMan]

I want to drag up this ancient (in aviation years) thread and bring it forward to todays ADS-B, Bravo airspace ruling with a question:

On today’s VFR charts, there is a 30 nM radius circle around Bravo airspace that seems to indicate that anywhere inside this circle, even underneath the veil, Mode C and ADS-B is required. I don’t think there is any question about that statement. My question becomes; Since it is under the veil, you are not in Bravo airspace, must you have a current VFR pitotstatic check in that portion which is inside the 30nM radius, but underneath the Bravo airspace.

I am trying to get the check on my airplanes done ASAP, but I need to make a flight very soon inside the circle, probably before the checks can be done.

Thanks in advance for your responses.

 

[flyingron]

Again, there is no required PITOT check. Altimeter / static checks are required only for IFR. There's no such thing as a "VFR pitotstatic check."

The only thing required for VFR is the transponder which includes the endoding system. You need to it to operate within in the mode C veil (even outside the class B boundaries) among other places.

 

[ateamer]

Suggestion: Be there in person when this check is done, ask questions and learn firsthand what they do to inspect it. No downside to knowing more about your plane and about maintenance procedures.

 

[Capt. Geoffrey Thorpe]

I am trying to get the check on my airplanes done ASAP, but I need to make a flight very soon inside the circle, probably before the checks can be done.

Per reg you are not supposed to operate your transponder without the check. ATC can give you an exception to fly inside the 30nm ring of death with it off if you call first.
Per reg you can not turn off the ADS-B and it has to report the same altitude as the transponder. I believe that ATC can provide an exception on that as well.

Options:
Get it checked.
Ignore the details of the reg and fly anyhow. My avionics guy commented that it was not unusual to work on aircraft that were 5 or more years overdue for the check.
Call ATC and ask for an exception to fly inside the circle with the stuff turned off (BTDT (pre-ADSB))