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By C1FF
#1854924
For a Part ML aircraft maintenance programme for a privately operated aircraft <2000kg, does anyone know if an annual altimeter calibration is mandated.

I understand the FAA require an altimeter calibration every 2 years.
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By Flying_john
FLYER Club Member  FLYER Club Member
#1855021
When my aeroplane was on a CofA it was an annual requirement and even though its now on a PtF I still carry out a check on Pitot and static instruments with a test box, for fear of transgressing the Altitude traps we have here in the south east.
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By User72
#1856786
Look in the AMC to Part ML. If your aircraft uses a maint prog based on the MIP (and its a big IF), then the only requirement in the MIP is
Pitot-static system Perform functional check.
What is a "functional check"?
GM1 ML.A.302(d)(2) says "A functional test (or functional check) is a quantitative check to determine if one or more functions of an item performs within the limits specified in the appropriate maintenance data. The measured parameter should be recorded."

My interpretation of that is that you must test what the altimeter reads at (at least) one height/altitude. Of course the person signing for the check can always refuse to sign off the check unless he does what he feels is necessary.

FAA requirements are not relevant - their rules are just different.
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By LAE B2
#1859135
Sir with respect it states 1 or more functions to check. The alt indication would be classed as 1 of the functions - however to ascertain an altimeter/adc indication is functioning correctly its necessary to carry out checks covering the operating range (as a minimum) as there will be a spread - hysteresis - of indications . Not one height only - but a range of heights - probably set out in the AMM..e.g 500,1500,3000,5000,8000,10K & the results thereof indicate whether the alt (function) is fit for purpose and can be released for service