iFly GPS Forum

Heh. Well, I wasn't, either, Cobra--just taking back some of the good things I said about FlightAware earlier.

"You were almost certainly receiving your company's signal directly from his transmitter, without any involvement of the FAA's ground network." 

I hope not--because both airplanes were seeing the other only sporadically. The other guy's is factory-built and came with ADS-B installed. Mine is amateur built, and the ADS-B passed the FAA's tests for owner-installed jobs.

"I know you are unhappy with your experience of ADSB in your aircraft, but I think at least some of your experience is just a fact of life when flying at low altitudes..."

Yes about altitudes. It's not that I'm unhappy about ADS-B. But I do think that anyone who assumes it makes them safe is in for trouble.

"When other aircraft are within line-of-sight, and if you guys are equipped so you can receive each others' signals, then you'll see each other, even down low."

I'd like to think you're right. But our experience is not comforting.  We can receive each others' signals sometimes, and occasionally down low.  But not regularly.

"But the FAA and especially FlightAware may not see you when you're down in the weeds."

That's been spotty, too.  Sometimes the FAA's test site tracks me all the way down to water landings, but more than half the time it drops out (in my usual test area) when I get below 500 or 1,000 feet.  And it has tracked me only twice when I didn't get above 2,000 MSL at some time during the flight. The terrain is almost dead flat here. A Class C airport is 13 miles away, and my home airport has a tower right next to the terminal building. I've talked with several FAA employees on the phone, and they all have waffled in that burearcratic way that lets you know they aren't going to commit themselves on the record.

So I'm just generally amused by the whole thing--or have been since figuring out that iFly is not part of the problem (if it IS a problem, of course).

Cobra, I understood what you meant about line of sight. Antenna location and groundplane construction is definitely a potential problem. All Seareys I know of have the ADSB antenna mounted under a wing, near the leading edge. That's apparently an approved location. But we builders have debated it for some time because most of us fly low a lot. I'll ask on the Searey Technical Site if anyone has actually installed one on top of the wing. The groundplane is necessary because it's a fabric covered wing.  Most guys have used an inspection port cover, but the factory-built Seareys have a dedicated groundplane and locate it farther outboard under the wing. On the other hand, my installation passed the FAA's installer test, and in actual practice it works. I'm just not sure how well it works. What I am convinced of, however, is that ADS-B doesn't guarantee flight safety yet.

I don't think ADSB was ever intended to "guarantee flight safety".  What it was primarily intended for was to reduce the requirement for expensive rotating surveillance radar stations, and eventually to allow smaller spacing requirements between aircraft (read:  Commercial Airliners Flying Into Busy Major Airports) for improved traffic flow.

The tin-foil hat crowd will also tell you that it's intended to let Big Brother track your every movement.  However, your experience puts the lie to that theory.