164
votes
Why do airplanes use MAYDAY when in danger but ships send SOS?
The difference here isn't between ships and aircraft: it's between Morse code and voice.
The SOS signal is only for Morse code. It's short, easy to send, and easy to recognise. But it's not as ...
- 12.6k
138
votes
Accepted
What happens if a language other than English is used over the radio?
During the 1990s I flew into countries on every continent except Antarctica. As an American English speaker flying U.S. registered airplanes, I never had a complaint that a controller had trouble ...
- 39k
117
votes
Accepted
How do civilian pilots and ATC verify that other people on the radio are who they claim to be?
This is a reasonable question, and to an outside the simple answer of We don't / can't might seem a little bit jarring.
After-all, we live in a time of hacking, terrorism and so on and I can ...
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111
votes
Why is "Affirm / Negative" used instead of "Yes / No"?
Why do we say "TANGO" on the radio for the letter "T"? Because "T" could get garbled or misunderstood to be "B", "E", "or "V". "NO" could become "oh?", "YES" could become "us", and so on...the ...
- 881
103
votes
Why do English-speaking pilots and ATC say "Niner" instead of "Nine"?
According to Wikipedia:
The pronunciation of the digits 3, 4, 5, and 9 differs from standard English – being pronounced tree, fower, fife, and niner. The digit 3 is specified as tree so that it is ...
- 98.1k
98
votes
Accepted
How was I able to just plug in my headphones and listen to ATC and pilot chatter?
This is a feature offered on some United Airlines aircraft and flights. It's an interesting way to hear what's going on in the cockpit. You can find lots of information by searching for United channel ...
- 9,114
74
votes
Accepted
What are the advantages of squawking 7700?
If you make a radio call, unless you are on 121.5 (or 243 military), then only the station you are talking to will initially know about the emergency. Initial calls should always be with the unit you ...
- 30.9k
70
votes
Accepted
Why is "Affirm / Negative" used instead of "Yes / No"?
Because it makes you sound cool and very Top Gun!
Negative Ghostrider. The pattern is full
Seriously though, short words, especially at the end and beginning of transmissions are often clipped. When ...
- 30.9k
67
votes
Accepted
Is it OK to greet ATC?
It is not part of the standard phraseology by any means, but it is fairly common, as is a very quick pleasantry when changing frequency.
[station name], Good morning, G-ABCD, [request]
and
G-...
- 27.6k
62
votes
Why does the ICAO alphabet use "Charlie" for C?
Hard C sounds too much like K. Ch (Charlie) will not be confused with K (Kilo). And soft C sounds too much like S (Sierra).
- 8,725
61
votes
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How does an Airbus aircraft connect to the Internet?
There are three different ways that aircraft can give internet access to its passengers, which will most likely be on at around 38,000 feet. First off, to have Inflight wifi, there needs to be a ...
- 690
60
votes
Accepted
Why do military pilots report "gear down" during their traffic calls?
In the U.S., military ATC (and civilian controllers working at military fields) are required to:
"Remind aircraft to check wheels down on each
approach unless the pilot has previously reported
...
- 26.3k
55
votes
Why do military pilots report "gear down" during their traffic calls?
Other answers mention "it's the rules" without specifying why the rules are what they are.
Civilian airplanes are for the most part assumed to be in proper working order after a flight, ...
- 6,227
55
votes
Why do we say certain things three times (e.g., "Mayday, Mayday, Mayday"), rather than two or four?
Yep, the critical commands are repeated 3 times. This ensures there is ABSOLUTELY zero doubt in anyone's mind (especially on a big crew airplane) of what needs to be done in a critical situation. It ...
- 511
52
votes
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How are duplicate call signs dealt with?
The scenario you're asking about is common. Let's say that your Delta 158 from South Korea to Detroit is running several hours late, and the decision is made to operate the A320 DTW-BOS on time. ATC ...
- 45k
51
votes
Accepted
Callsign includes the term 'with Kilo' ; What does that signify?
What that probably means is that the pilot is reporting that they have ATIS information kilo. Automatic Terminal Information Service (ATIS) is a radio broadcast on a specific frequency (often a local ...
- 52.1k
51
votes
Accepted
What does ATC do during "slow" times?
Admin stuff, emails, chat with a colleague if you are not alone on shift, read up on (ever changing) procedures, eat, read a book, make sure the coffee machine works, meditate, watch TV. Anything goes,...
- 35.4k
50
votes
What is your responsibility when a distraught pilot is on frequency?
On frequency, if control is responding to the distressed aircraft you should stay quiet and let them work the problem. This would not be a great time to ask for flight following or traffic advisories ...
- 98.1k
50
votes
Accepted
Should I contact ATC if I don't have a transponder?
Every US controller I've ever heard from says they'd prefer to be talking to every aircraft in their airspace, period. This lets them know your intentions and allows them to move you around if needed, ...
- 27.4k
49
votes
Accepted
What kind of assistance can another aircraft provide to an incapacitated pilot?
This is speculative and I haven't looked at the links you gave, but I can think of a few things:
Having another aircraft there gives ATC a way to gather information that they otherwise couldn't. For ...
- 71k
47
votes
What happens if a language other than English is used over the radio?
This is much more common than just the countries you list. In Mexico, for example, ATC communications with Mexican carriers are entirely in Spanish and many of the controllers have thick accents.
...
- 35.1k
44
votes
Is it OK to greet ATC?
Technically you are not suppose to and for the greatest safety, internationally recognized vocabulary should always be used.
However, I have noticed most heavy pilots and many controllers do a ...
- 11.2k
43
votes
How often does a pilot ask ATC for a repeat?
How often is hard to quantify, but in general I would suggest the answer is all the time.
ATC is there to help you, as a service to you as a pilot. Sometimes out of necessity things are said quickly ...
- 27.6k
42
votes
Accepted
When should a pilot use the word "takeoff?"
The word "Takeoff" should only be used when clearing somebody for takeoff, acknowledging your takeoff clearance, or cancelling/acknowledging a cancelled takeoff clearance.
"Departure" should be used ...
- 10.4k
42
votes
Accepted
Does air traffic control identify a distress situation when an aircraft flies triangles in the sky?
To my surprise, this does exist, at least in the UK. According to the Manual of Air Traffic Services:
7 Emergency Triangle Procedure
7.1 Pilots lost or uncertain of position and experiencing ...
- 71k
41
votes
What is meant by "Fox Two"?
Fox codes are used by NATO military aircraft to designate a release of an air-to-air munition, generally missiles.
Fox One is a semi-active radar guided missile, for example the AIM-7 Sparrow. This ...
39
votes
How was I able to just plug in my headphones and listen to ATC and pilot chatter?
ATC and aircraft communications (at least in the US) are not restricted for receiving. Anyone can purchase (or make) an "Air band" receiver (or scanner radio) tunable through (roughly) 118-140 MHz and ...
- 301
38
votes
What are the advantages of squawking 7700?
Aircraft squawking 7700 are getting a special indication (e.g highlighted, distinct colour, boxed) on Air Traffic Control (ATC) displays. This helps to identify the emergency aircraft not only to the ...
- 77.1k
38
votes
Accepted
Why do we say certain things three times (e.g., "Mayday, Mayday, Mayday"), rather than two or four?
Procedure calls for the mayday distress signal to be said three times in a row so that it won't be mistaken for another word or phrase that sounds similar under noisy conditions. The use of Mayday ...
- 486
37
votes
Accepted
What is your responsibility when a distraught pilot is on frequency?
Do not respond to irrelevant chatter on aviation frequencies.
There are already way too many people who think it is ok to chit chat and joke on the radio while they are flying.
Not only does this ...
- 13.1k
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