Altimeter Calibration Height

Honestly, I don't know how you guys got Newton involved.

How about a (better) hypothetical?

The imaginary aircraft is sitting at Imaginary Airfield (KIMG), which
sits at a billiards-table-flat 50 MSL. The aircraft's static port is
mounted at the centerline of the fuselage, which is 10 feet from the
ground. The instrument in question is mounted 4 feet above the centerline.

What will the gauge read when set to the proper barometric scale? 50,
60, or 64 feet?

TheSmokingGnu

TheSmokingGnu wrote:
Honestly, I don't know how you guys got Newton involved.

How about a (better) hypothetical?

The imaginary aircraft is sitting at Imaginary Airfield (KIMG), which
sits at a billiards-table-flat 50 MSL. The aircraft's static port is
mounted at the centerline of the fuselage, which is 10 feet from the
ground. The instrument in question is mounted 4 feet above the centerline.

What will the gauge read when set to the proper barometric scale? 50,
60, or 64 feet?

Not enough potential aswers, you for got:

Under IFR

Under VFR

Pass Go and collect $200

No one is going to tell me how to set my altimeter

--
Jim Pennino

Remove .spam.sux to reply.

What will the gauge read when set to the proper barometric scale? 50, 60, or 64 feet?

That depends on what the people in the calibration shop did to it. My
understanding is that the =installation= is certified. It would be
logical for the certified installation to be calibrated to the wheel
height. It would be equally logical for it to be certified to the
instrument height.

It's an FAA certification. 'nuf said.

Jose
--
Get high on gasoline: fly an airplane.
for Email, make the obvious change in the address.

On Apr 3, 12:11 am, TheSmokingGnu
wrote:
The imaginary aircraft is sitting at Imaginary Airfield (KIMG), which
sits at a billiards-table-flat 50 MSL. The aircraft's static port is
mounted at the centerline of the fuselage, which is 10 feet from the
ground. The instrument in question is mounted 4 feet above the centerline.

What will the gauge read when set to the proper barometric scale? 50,
60, or 64 feet?

Any of the above ;-) To repeat what I posted back on March 9th...

The actual altimeter test is described in FAR 43 CFR Appendix E, and
allowable error varies from 20' at sea level, to much more at higher
altitudes.

http://www.flightsimaviation.com/dat...t_43-appE.html

In theory, the instrument is calibrated on the bench to read at its
own height, but can later be adjusted in the aircraft to read wheel
height. Whether it should be or not, doesn't seem to be addressed in
the regulations that I could find.

There's an old saying, that "hell for scientists" is defined as a
place where all the conditions are perfect, but none of the
instruments are.

Kev