View Single Post
  #2  
Old May 30th 12, 03:19 AM posted to rec.aviation.soaring
Darryl Ramm
external usenet poster
 
Posts: 2,403
Default Position Recorders, Accuracy, and Badge altitude gains

On Tuesday, May 29, 2012 12:52:24 PM UTC-7, wrote:
On Sunday, May 27, 2012 4:44:25 PM UTC-4, Tony wrote:
Leah and I are down here at Chilhowee for a VSA rally and had an enjoyable flight in the Ka7 today attempting a silver altitude gain for the highly sought after VSA Silver Coin. Unfortunately by the time we were hot, tired, hungry, in pain, and had to pee we hadn't quite made the gain. I found the trace for my FlywithCE interesting though. We released about 2400 MSL and I soon remembered that I hadn't turned on the FlywithCE. So I turned it on at about 3000 I think. Check out the trace: http://www.onlinecontest..org/olc-2....l?dsId=2421969

It seems that the FlywithCE was trying to insist that I had started on the ground, then realized that wasn't right, and attempted to correct for it by jumping the altitude up about 3000 feet. If it had just recorded the actual altitude it would've been fine. I would've had a trace starting in mid-air, right where I turned on the recorder.

The IGC decided that position recorders like the FlywithCE will be allowed for Silver and Gold altitude gain after this fall. Would I be able to claim this obviously bogus trace for Silver Altitude? (evil grin). I suspect this is a problem associated with not turning the thing on until mid flight but dang shouldn't it just record what the actual position is???


When your observer goes to fill out the badge application, he or she has to make some statements as to how the flight log was controlled. It would seem reasonable to expect this might include noting that the logger was not only properly installed, but on.
Try again Tony
UH


It might seem reasonable to expect official observes to do lots of things. But there is no requirement AFAIK for the OO to report anything except that they observed the flight, even when required to do things like seal a particular model of flight recorder to the cockpit I suspect many badges have been approved where it is assumed the OO did things that they did not. At least with the current SSA OO worksheet the OO gets to check a box they either sealed the flight recorder to the aircraft or observed the aircraft after landing. Nowhere on that SSA form is there any mention of the flight recorder being powered on or a place for the OO to note that the flight recorder is powered on/operating before flight.

There is no requirement in anything I can recall in the sporting code, pilot & OO guide or any flight recorder or position recorder document that requires (or even suggests) the OO note that the flight recorder is powered on before flight. And in practice from most of the badge and record flights I've seen the turning the device on before the flight has been left to the pilot. And just being on may not be enough. An OO would ideally need to note that the device has acquired a 3D fix or or has been on long enough to be expected to acquire a 3D fix.

Not all of these devices provide the pilot/OO with a way to determine if a 3D fix is being correctly received, and for some devices with a slow cold start (e.g. if the receiver has been powered off a long time and/or moved a long distance while off) and/or poor antenna location this might take significantly longer than folks are expecting. And without that indicator if there was a non-obvious antenna problem the OO might assume things are fine, and if the devices then (as might be the case here) report invalid 3D fixes as if they were valid then there may be no way to work out the data in invalid. This really seems to be a technical issue that deserves investigation, not something that hoping that human (OO) procedures can or should somehow paper over. If I'm missing any relevant rules or guidance here please let me know.

Darryl