171–180 of 197 posts
Earlier quoted context omitted.
Dumb question: how would a cellphone work given they don't work on passenger aircraft?
General aviation flies a lot lower and slower than passenger jets.
Earlier quoted context omitted.
I've found that unless I'm under about 10000' and under about 150 knots, cell phones don't work very well in GA either.
Nice plane you have, if you fly above 10000' or above 150 knots frequently :-)
Living in San Francisco, I've always been curious if GPS will eventually let both SFO runways stay open in poor visibility conditions one widely adopted. Does anyone know?
Earlier quoted context omitted.
> Air traffic controllers have primary radar and secondary radar in addition to ADS-B information. No they don't. Most secondary (surveillance) radar in the US has been shut down already. The FAA has been busy shutting down basically anything that requires maintenance, and LORAN is gone too. I believe the whole point of ADS-B out was to shut down basically the rest. Source: commercially-rated pilot.
So then if everything goes to ADS-B and GPS, doesn't that create a potential single-point-of-failure scenario, as isn't the data that ADS-B sends out itself derived from GPS? Having all navigation information come from a single source strikes me as about a good idea as the single AoA sensor on the 737MAX. I'd like to be wrong about this, but I'm not sure how I am. How am I potentially wrong about this?
It doesn't have to make sense.
Earlier quoted context omitted.
Are they also getting rid of VOR for navigation? https://en.wikipedia.org/wiki/VHF_omnidirectional_range (Sorry, paywall is blocking me)
Not too familiar with aviation or IFR. Isn't VOR primarily a beacon that you use to orient yourself, doesn't seem like it helps the ATC maintain separation etc..
I suspect VORs will be kept for airport locations and en route instructions, but most others will be shut down in favor of GPS.
Earlier quoted context omitted.
General aviation flies a lot lower and slower than passenger jets.
I've accidentally had phones on during takeoff and they lost signal within seconds. Were they already going too fast? Or was there jamming?
A lot of comments seem to be about spoofing. Remember that there are multiple humans in the loop -- experienced pilots and experienced air traffic controllers -- and multiple levels of redundancy. Pilots have access to barometric altitude, radar altitude, traditional VHF navaids, TCAS-issued resolution advisories (based on directional antennas, not GPS)... in addition to GPS. Air traffic controllers have primary rada…
> buying an aviation radio off the shelf and just chatting on the frequency or issuing fake clearances if you want to be a mass murderer Incidentally, I am happily surprised that that never seems to happen. One could so easily create so much chaos at an airport... There is no authentication whatsoever.
https://en.wikipedia.org/wiki/Airband
One of the reasons why airband radio uses amplitude modulation is so that a much more powerful transmitter (ground based, operated by air traffic control or tower personnel, with access to very high Tx powers), can transmit on top of spurious transmissions coming from low powered aircraft or handheld transmitters. The big ground based Tx can step on an interloper and communicate its message to all aircraft on the same frequency.