On 9 Jul 2003 09:59:04 -0800, (Mark James Boyd)
wrote:

My Volkslogger had some courses in it, and I had declared
one by pressing buttons. I changed my mind, disconnected
power, and wrote a written declaration. I reconnected
power and flew the flight. Much to my chagrin, the logger
had the old declaration on the .IGC file. Yep, I tested
this a couple more times. Bad feature. I've now eliminated
all courses from the logger. Problem solved, no more
electronic declarations. Since you have to provide the .igc
file with the paperwork, and the electronic declaration
is more recent, no way around this otherwise. Also be careful
because a small power interruption can cause this same redeclaration.
I use a seperate battery for the VL (actually a drill battery).
I like the idea of a written declaration anyway so my
towpilot and crew know the plan.

Thanks for the clarification. That makes sense now.

I'm surprised with what you say about the time stamp on the electronic
declaration. The EW model D manual says that the declaration is time
stamped from the logger's internal clock when the declaration is
recorded and that this time stamp is retained until the logger's
internal clock is reset, at which time the task declaration is wiped
and must be re-entered.

If the VL doesn't treat the declaration time stamp the same as the EW
model D then I'm certain you've done the right thing by clearing all
declaration information out of it. However, it may be worth double
checking that it really does reset the time stamp on power recycling
before giving up on electronic declaration.

I don't use electronic declarations, but then I use the EW model D,
which is a portable device that can only have a declaration recorded
via a computer (no keyboard - only one button on it) and I don't own a
glider, so may not always fly the same one. This just means that a
paper declaration is more convenient for me, but ymmv.

Technically I think tampered
with means and includes removing power from the VL.

That varies with the type of logger. Most loggers that use external
GPS receivers also include disconnecting the GPS as tampering. The EW
model D could care less about power (it has a 9v built-in backup
battery) but it records GPS disconnect/connect events, so
tamper-proofing includes looping the GPS data line round a permanent
part of the glider structure in such a way that it must be
disconnected to remove GPS and/or logger from the aircraft.

Also, if
you run out of memory before the OO disconnects the logger, how
can the OO verify the trace?

Is the VL so memory limited? The EW model D will record GPS and
pressure for 24 hours at a 4 second sample interval. I'd assumed this
was pretty standard.


--
martin@ : Martin Gregorie
gregorie : Harlow, UK
demon :
co : Zappa fan & glider pilot
uk :