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By AlanC
#1806555
MikeW wrote:Totally irrelevant.
It's barometric. Pressure transducer.


Aha. Yes, so I see. I was thinking of something totally different, weekend memory strikes again :oops:. Still a point worth making though for others, given the increasing amount of airspace infringement reports where a GPS log is used as proof of altitude, much as with a low flying issue I consulted on last year elsewhere in the world, where a regulator tried to use a GPS log as proof of negligence.

Modern barometric transducers a much better way than an ageing mechanical system :thumleft:!
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By Flying_john
FLYER Club Member  FLYER Club Member
#1807883
a. Barometrically derived altitudes are required for pilot compliance with published and air traffic controller-issued altitudes within the National Airspace System. The coexistence of barometric and geometric altitudes in the flight deck may confuse pilots, due to their similarity. For example, corrected barometric altitude and geometric altitude relative to MSL represent height above MSL, even though they differ by how they’re derived.

b. Pilots reading geometric altitude relative to MSL could reduce their vertical separation from other aircraft, because geometric altitude sometimes differs from the barometrically derived altitudes that other aircraft are using.

c. It’s important, therefore, to make geometric altitude relative to MSL clearly identifiable and distinguishable from barometric altitude, so pilots won’t confuse them and risk a reduction in vertical aircraft separation.
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By Smaragd
FLYER Club Member  FLYER Club Member
#1911308
Unfortunately at the moment some previous posts on this thread are not visible, so perhaps my question has already been answered. I have the instructions for resetting a Kollsman altimeter pressure setting (lock screw on the front, pin on the side). However my altimeter is a United Instruments 5934 with just a screw on the front next to the main adjustment knob, nothing on the side. Does anyone know how to reset this altimeter?
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By xtophe
#1911330
From memory, the screw need to be removed completely, a tiny screwdriver or unfolded paper clip used to move aside a little "copper or brass" plate. Then the knob can be pulled and adjusted.

Then realign little plate with tiny screwdriver and reinstall the screw
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By Smaragd
FLYER Club Member  FLYER Club Member
#1921561
xtophe wrote:From memory, the screw need to be removed completely, a tiny screwdriver or unfolded paper clip used to move aside a little "copper or brass" plate. Then the knob can be pulled and adjusted.

Then realign little plate with tiny screwdriver and reinstall the screw


That did the trick! Thanks to all for the help.