Check airspeed indicator Annual inspection

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MoonlightVFR
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Joined: Sun Jan 02, 2005 5:55 pm

Check airspeed indicator Annual inspection

Post by MoonlightVFR »

Twenty five years ago I had a disappointing experience.

Aircraft in for annual inspection. It passed . Paid the fees at front desk.

Went to airplane and discovered hole in headliner, zipper in headliner deceased.

The biggy was that air craft was tied down and the air speed indicator was registering 40 Knots ; setting still. Yes someone blew it up with compressed shop air.


What is the current suggested procedure for testing this instrument in annual inspection. Instrument is working perfectly.
No squawk?. Does it even have to be tested since no squawks?
gradyb, '54 B N2890C
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Bruce Fenstermacher
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Re: Check airspeed indicator Annual inspection

Post by Bruce Fenstermacher »

No requirement to test as far as I'm concerned. Want to know what should be done at an annual inspection? Look at Cessna's check list as well as the 100 series service manual and 43.13 appendix d: https://www.ecfr.gov/cgi-bin/text-idx?c ... 1.43_117.d
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Bruce Fenstermacher, Past President, TIC170A
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GAHorn
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Re: Check airspeed indicator Annual inspection

Post by GAHorn »

The 40 mph static indication is certainly an indication of "improper operation." Had the aircraft been approved for return to service?

A "home brew" method of testing/calibrating your airspeed can be found here: http://www.iflyez.com/manometer.shtml
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Bruce Fenstermacher
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Re: Check airspeed indicator Annual inspection

Post by Bruce Fenstermacher »

gahorn wrote:The 40 mph static indication is certainly an indication of "improper operation." Had the aircraft been approved for return to service?

A "home brew" method of testing/calibrating your airspeed can be found here: http://www.iflyez.com/manometer.shtml
George, reread his post carefully. That static reading was 25 years in the past. Instrument is currently working perfectly. He is asking how to check it at annual. I'm wondering why he would be checking it if it is operating normally. I wouldn't.
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GAHorn
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Re: Check airspeed indicator Annual inspection

Post by GAHorn »

I got the "jist" of his original post and made my post accordingly. The question asked "Was the aircraft approved for return to service" was intended to point out that any damage caused by the shop is still their problem....especially so if they've approved it's return.... and also to point out to all that approval for "return to service" by the repairman/shop is mandatory after work is performed.... before the [uowner/]pilot[/u] may actually return it to service. It's a shared responsibility.

The link was added for general information.

FAR43 (as you so correctly posted, Bruce) specifies the instruments MUST be inspected. The degree to which they are "inspected" is up to the judgement of the inspector and the tolerance of the owner.
Inspection...(is it installed correctly? is it's pneumatic lines connected? is it in good condition? is it's glass clear and not cracked?..) ...is not TESTING. A visual inspection and a confirmation of operation (owner/pilot statement of operability) is all that's necessary to meet the rule, IMO.
IN fact,.... an inspector who "tests" the instrument had better hold certification as an instrument repair station, ..... or he's exceeding his certification authority and he'd better not mess with it other than look at it. :?
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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c170b53
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Re: Check airspeed indicator Annual inspection

Post by c170b53 »

Pitot static check required each 24 months to check the blind encoder /altimeter correlation, guess what other instruments should be checked also. My VSI is out a bit, (no wonder I thought my engine conversion is fantastic :D )
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
flyboy122
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Re: Check airspeed indicator Annual inspection

Post by flyboy122 »

They make a piece of equipment to check this. It's made by Barfield, and a lot of shops have them. The one I used did pitot/static and airspeed. It's pretty nifty and easy to use, but probably something you are better off borrowing than owning.

DEM
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DaveF
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Re: Check airspeed indicator Annual inspection

Post by DaveF »

My ASI is checked every two years by the guy who does my 91.413 and 91.411 static and transponder certs. He doesn't charge extra, he just does it because his Barfield box can, so why not?
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