SeeYou works perfectly well on an Intel Mac with Parallels. And at
least you can continue to use a computer that looks as if it was
designed by a grown-up with some aesthetic senses.

I have heard that some Mac based gliding logbook software is under
development which will display IGC traces including engine noise
level. Hopefully it will be featured in an up-coming issue of Keep
Soaring.

SeeYou most definitely does _display_ engine noise level and I believe
MOP levels _where they have been recorded by the logger_.

However, whether ENL or MOP is recorded is another matter. This
depends mostly on whether the logger is fitted with an Engine Noise
Level sensor.

Even if it is fitted with a sensor, this may not pick up
all engine level readings. This is currently a vexed question with the
FAI in IGC files. The noise of many electric and even jet engines are
not reliably picked up by current ENL sensors even though the noise
from jet engines is very clearly audible from outside.

To see if ENL has been recorded, check the IGC file. In the "I record"
near the top there should be an entry for ENL if the recorder is
capable of doing this…

I073638FXA3941ENL4246TAS4751GSP5254TRT5559VAT6063OAT

>From memory, the entry <3941ENL> means that engine noise level is
noted in the B record between bytes or fields 39-41.  The entry can be
a maximum of 999 and should ideally be this when the engine is running
normally.

B0845084909336N00833938EA005800050400799 910 8831328601400624

I guess they count from 0 like most nerds.

B084508490 9336N00833 938EA00580 00504007 999 108831328601400624

The numbers 999 should be the ENL record showing max engine noise.

If you are in doubt as to whether software such as SeeYou is at fault
or the ENL recording, you can easily check the traces on the OLC where
you can see ENL on a self launcher on the flight profile. Something
similar is normally shown in SeeYou.

Well that's the dream anyway. The reality with some new propulsion
systems is a bit different and the FAI have been a bit slow to respond
and in any case, it is not really easy.

The notes which follow are from the 2010-2011 FAI "technical
specifications for GNSS flight recorders" which can be downloaded from
the internet from an address which changes by the hour as the FAI move
the files around.



5.6.3 ENL and MOP numbers. The three ENL and MOP numbers as recorded
in IGC files must therefore differentiate between the "quiet engine"
and the "noisy cockpit" cases. This is done by carefully selecting the
frequency and gain at which the ENL system is most sensitive, and in
the case of MOP systems, testing the sensor provided by the FR
manufacturer, which could be acoustic, RPM, fuel flow, temperature
(for instance Jet Pipe Temperature). The ENL and MOP system is then
tested by GFAC in a range of motor gliders, gliders and powered
aircraft.

B8.5 Means-of-Propulsion (MoP) recording system. Tests will be made on
recording systems for the Means of Propulsion for motor gliders. Such
systems include those under Three-Letter Codes ENL and MOP. The
critical cases are described in para 5.6 of the main body of this
Specification. Tests will be made with the Recorder in a number of
types of glider and motor glider. These will include gliders with low
aerodynamic cockpit noise, also those with higher cockpit noise in
gliding flight. If the required results are not shown, modifications
to the ENL system must be made until they are, or an additional sensor
added under the MOP three-letter code (para 5.4 in the main body of
this document). For other aspects of ENL systems, see Chapter 5 of the
main body of this Specification.

B8.5.1 Tests with MoP running. Operation of both two-stroke and
four-stroke engines will be tested at power settings from maximum
power to power for level flight at slow speeds. Results will be
analysed to ensure that a clear difference in the IGC file data is
shown between all types of gliding flight, and any engine running at
positive thrust settings. A critical test will be with a relatively
quiet engine, typically a 4-stroke engine in a motor glider at power
for level flight.

B8.5.2 Tests without MoP running. For gliding flight, tests will be
made with the cockpit ventilation and other panels open, both straight
at high speed and during turns. In many gliders an "organ pipe" noise
can be heard in the cockpit and ENL will be recorded for this
condition. A particular test that will be made is turning at typical
thermalling speeds with cockpit panels open, because this is often
done when it is hot, and if the ENL is too high under this condition
it could be mistaken for a climb under power.

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