Cambridge Model 20 Issues

X-no-archive: yes
In article , Eric Greenwell
writes
Greg Arnold wrote:

Brian Iten's file with the high noise reading in on the OLC site for
April 4, if anyone wants to look at it.

I think we need the original file (.cai format) from the logger. The
noise recordings look much too high for gear down noise. What program
was used to produce the IGC file from the CAI file? If it was the
cai2igc.exe, perhaps that program does not rescale the engine noise
level to the IGC values?

I have has a look at Brian's .IGC file and it show maximum values of
195, which suggests that any rescaling is being done by the viewing
program and not on conversion to .IGC format. The download was done
using SeeYou.

What I do see is that the maximum value of 195 (equivalent to 999 on any
other recorder, and top-of-scale for Cambridge 10/20/25) is reached and
sustained (flat tops to ENL graph) during both Take-off/Tow and final
stage of flight to landing (presumably when the wheel was down), as well
as occasionally during what I take to be urination.

The ENL on this recorder is abnormally high. A new design of recorder
showing these characteristics would not get IGC approval.

I would guess that the ENL system on this recorder is in need of
adjustment/repair.

Best regards,

Tim Newport-Peace.
Technical Advisor to
Global Navigation Satellite System
Flight Recorder Approval Committee (GFAC)
of the International Gliding Commission
of the Federation Aeronautique Internationale