Pitot-Static system test

[NC Bill]

Since the CT isn't certified for IFR is a bi-annual test of the pitot-static system required?

[Jim Meade]

 No, not required per FAR 91.411.   You must have the test if you are flying in controlled airspace under IFR.  You could fly practice IFR approaches (under VMC and VFR) and still not need the tests.

 

 Whether it's a good idea is a different question. 

 

 

 

 

\§ 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 appendices E and F of part 43 of this chapter;

 

 

[NC Bill]

That's the only requirement I could find also, Jim. 91.411

 

Thought I must have missed something.

[Doug Hereford]

NC Bill,

Don't forget however, that if you operate in the airspace listed in FAR 91.215, you need to have your transponder certified every twenty-four calendar months. This requirement is specified in FAR 91.413 and is commonly refered to as the "VFR check". It sends one to FAR 43 app. F. This appendix specifies the exact things that must be looked at on the transponder system. FAR 43 app. F is fairly limited in the scope of what is actually checked. Transponder power, frequency, and minimum triggering level are the main items. Side lobe suppression is also verified. The actual check is very quick, and will probably run under $120.00. (I used to charge $70).

 

Some things to keep in mind here: FAR 91.413 requires that if any maintenance is done which could introduce data correspondance error (altimeter/encoder/transponder) the integrated system must be checked IAW FAR 43 app E ©. What this actually means is that if you remove and reinstall the transponder, encoder, install new equipment, or repair associated wiring regardless of whether or not you fly IFR, the integrated system must be checked. Also, this check must be performed by an appropriately rated repair station or aircraft manufacturer.

 

As an appropriately rated repair station, I used to perform numerous VFR checks. I don't do them any more. The nature of the involved equipment (altimeter, encoder, transponder, and static system) is such that integrated system errors can occur over time. Altimeters are nothing more than calibrated barometric pressure instruments, and can drift out of tolerance, encoders drift as well. Static systems easily develope numerous leaks over time, and many maintenance people don't realize that R&R of transponders and or encoders or opening of static systems (except drains) can introduce integration error (which requires checks IAW FAR 91.413). What all this boils down to is that you can be flying around VFR, reporting an altitude much different that your actual flight altitude. ATC may be separating traffic based on reported altitudes for VFR and IFR traffic. This could set-up a dangerous situation. I now only do the "IFR checks" for this reason.

 

My advice is to have the IFR check done every twenty-four calendar months even though the regulations don't require it. It does however, run up to three times as much money (assuming no problems) but it is well worth it.

 

Doug Hereford