Radio communications gettin stepped on ?

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What is deal today with aircraft freq use when two or more planes or
ATC try communicating on same freq ? (Stepping on each other) Do you
still get that ugly squeal like metal screeching sound ?
How come in over 30 years there hasnt been some better newer
improved means so this does not happen ? It is awful scary when the
freq gets busy and when this happens or ya can't even get a word in
to tell ATC your position or intentions when the airport gets busy.

Is there some way pilots or ATC handles this better these days ?

It seems really incredible this still exist in 2010, that this very
poor means of communicating with many aircraft sometimes in a
confined smaller area like at airport where lot of planes are trying
to takeoff or land. Is this such a big difficult technical problem
to solve or at least improve ? I know the big airlines also use a
datalink as additional means to transmit info. Do the big jetliners
also have to deal with this radio "stepping on" problem ?

-- jim kenn, March 7, 2010


About ten years ago, the FAA put a lot of money and effort into a "next-generation" digital radio link. alludes to this. Basically the program was scrapped because the cost to both the FAA and the airlines had skyrocketed. If the FAA had been involved with the cell phone network, you'd be paying $10,000 per month for service.

Do airliners deal with this problem? Yes. Captain Sully's initial emergency call after the bird strike NW of LGA was stepped on.

-- Philip Greenspun, March 7, 2010

To answer your follow-up question below... It doesn't matter if you can't talk to ATC. ATC's job is to separate airplanes in instrument conditions. If a pilot can't talk to them, he or she is supposed to continue to fly his/her clearance, possibly all the way to a landing at your destination, and they will talk to other pilots to vector them out of the no-radio aircraft's way.

ATC cannot fly the airplane for you. They are not there to take split-second action. If you can't break into the chatter while still outside the Delta airspace, fly a couple of big circles and try again. If they've assigned you to enter a right downwind Runway 29, there is no need for you to talk to them again until you're on the downwind wondering what your sequence is (i.e., whom to follow). If they don't give you a sequence and you can't break into the frequency, I think it would be perfectly legal to continue on the downwind and make a left turn to the north, exiting the Delta airspace to try again.

This is why pilots are required to carry reserve fuel. Inability to land immediately or talk to ATC is not supposed to result in an emergency.

-- Philip Greenspun, March 7, 2010

Oh yeh think I remember now when Sully called the ATC hearing the weird garbled radio feedback during his emergency. This whole aviation radio limitation problem is really really frustrating I think to most pilots especially in an emergency and is pretty scary at times. Sometimes it gets so busy at Hanscom you can't talk really to ATC because every second is taken up with ATC or other planes talking. It made me pretty nervous sometimes when coming back into Hanscom trying to land when it was so busy.

Has the FAA ever figured out over all the years how many accidents that maybe this radio limitation thing might have contributed or been the cause ? What tips or ways can you deal with it or get by safely at least when it gets super busy like this on the radio ?

-- jim kenn, March 7, 2010

Here are some tips I use:

1. Be brief on the radio. If everyone uses this advice, there is less congestion. My flight instructor always reminded me to try to lose the "umms" in your radio calls and when called by the shortened form of your call sign (12A instead of 1234A), to reply with the shortened form.

2. Make your radio calls allowing for the possibility that there will be congestion. For example, if I am flying into a Class D, I don't wait until I am 1 nm out to try to make my call. I will probably make it 5 nm out or so. That way, if I have to wait for the frequency to open up, I still have plenty of room.

Also, at our local airport, we are 3 nm away from the Class B surface area for SFO. Because the time is so short, I request my Bravo transition ("cleared to enter Class Bravo") from our ground control, who requests it for me from SFO while I am taxiing.

3. Have an alternate plan just in case. If you can't get through (or if your have radio failure), think ahead of time what you would do. It is usually pretty simple. For example, I would turn away from the Class D if I couldn't get through to them on the radio, but I am more relaxed if I think through ahead of time what I would do.


-- Todd Ramming, March 7, 2010

another thought is just to wait a second and listen to the frequency before speaking/ checking in. Rather simple, but it works every time.

-- Rob Evers, March 17, 2010