Post by w***@cox.netNo sour grapes here. I've been a little out of the loop for a couple
of years when it comes to matters of officialdom. However, if you're
going to play the game, officially, you need to be up on things. I
know this from past experience, and it really is my fault for not
checking more thoroughly ahead of time.
Dear Gary,
I feel for you, having flown such a great flight and then to find out
that your recorder is no longer IGC-approved for World Records or FAI/
IGC badge flights. Mind you, in my record-breaking days I had a
number of flights turned down for failures to comply with one aspect
of the rules or another, so I've been there too! One flight I did
before the days of IGC-approved recorders, was turned down because the
proof that the motor glider engine had not been run was not positive
enough. So, the next weekend I flew it again but had an OO seal the
engine inside the engine bay with tape (which could have been broken
if I needed to run the engine to prevent a field landing). The tape
was unbroken at the end of the flight and it was validated. Now, with
IGC-approved recorders we have a much better worldwide system.
As you generously say above, you should have checked. On that point,
it it easy for anyone to check by simply going to the IGC GNSS web
site and downloading the latest IGC-approval document for that type of
recorder. In your case the three legacy Cambridge models 10, 20 and
25.
Go to: http://www.fai.org/gliding/gnss
then go straight to the end where there is the list of IGC-approval
documents for all 43 types of IGC-approved GPS recorders from 16
different manufacturers. BTW, there are three new types of recorder
under test for IGC-approval at this moment.
On the IGC GNSS web site, there are also free downloads and many other
things. For example, the free IGC Shell program for downloading and
validating IGC files, which was created by distinguished SSA member
Marc Ramsey, who often posts on this newsgroup.
The issue with the three legacy Cambridge models was wider than the
lack of Public/Private Key security. With 43 types of recorders with
all sorts of different characteristics, it was becoming more and more
difficult to treat them all in the same way. Therefore, in 2005, IGC
introduced a series of different IGC-approval levels for ALL IGC-
approved recorders. These levels are listed in para 1.1.3.3 of Annex
B to the Sporting Code (also on the IGC web pages).
Another factor with the legacy Cambridges is that the IGC Validation
process does not work with the IGC file, only with the CAI binary
format. There have been several cases of pilots losing flight
validation because they did not realise this and lost the CAI file.
The IGC GFA Committee asked Cambridge several times to change their
external software so that IGC file would validate directly, but this
was not done in the commercial turbulence that happened after Dr David
Ellis sold the business and it moved from Vermont. You might think
that you could always go back to the recorder and extract the CAI
binary. However, this may not be in the recorder because with these
early models, if setup information is changed, previous flights are
erasedfrom the memory. Bear in mind that the memory capacity of all
older-generation recorders is much less than modern ones and, except
for the Volkslogger, old files are over-written when the memory is
full. For instance, I remember a flight by Chris Rollings that was
over 12 hours and his legacy Cambridge recorder ran out of memory at a
4 second fix interval and started over-writing the first bit of the
flight.
If you read the IGC-approval document for the legacy Cambridges, these
cautionary notes are included, and some others.
So that's the moral, every now and again go and look at the
information provided free for you on the IGC web site !
Regards to all SSA people from this side of the pond,
Ian Strachan
Chairman IGC GFA Committee
Lasham Gliding Centre, UK