Discussion
I have a plane app on my phone which alerts me to icao codes amongst other things.
It seems that planes squawking 7700 in the UK happens many times a day. Isn't it an emergency code? What circumstances are these codes used and why are there so many of them? Does anyone have any real world examples?
It seems that planes squawking 7700 in the UK happens many times a day. Isn't it an emergency code? What circumstances are these codes used and why are there so many of them? Does anyone have any real world examples?
Yes it is an emergency code.
Any transponder equipped aircraft can use it. Basically a declaration to Air Traffic Control that I have a problem and I'm going to need help. Could be anything...
In the airline world, ATC centres will filter out traffic above or below their part of the sky they are responsible for. Eg, low level ATC unit for traffic lower down will filter out high altitude traffic. IF, and aircraft ( high up) squawks mayday (7700) it will appear on that particular controllers screen indicating that aircraft has an issue up high and might possibly be about to hurtle down into his/hers airspace very rapidly. We can descend at massively higher rates in an emergency than we would normally do.
The last time I had to use it (quite a few years ago) was for a passenger cardiac arrest. I had to dive down and went straight into Manchester from 39000ft. ( You don't forget these kinds of flights!).
Why so often? Who knows,
Any transponder equipped aircraft can use it. Basically a declaration to Air Traffic Control that I have a problem and I'm going to need help. Could be anything...
In the airline world, ATC centres will filter out traffic above or below their part of the sky they are responsible for. Eg, low level ATC unit for traffic lower down will filter out high altitude traffic. IF, and aircraft ( high up) squawks mayday (7700) it will appear on that particular controllers screen indicating that aircraft has an issue up high and might possibly be about to hurtle down into his/hers airspace very rapidly. We can descend at massively higher rates in an emergency than we would normally do.
The last time I had to use it (quite a few years ago) was for a passenger cardiac arrest. I had to dive down and went straight into Manchester from 39000ft. ( You don't forget these kinds of flights!).
Why so often? Who knows,
aeropilot said:
silverfoxcc said:
LimaDelta said:
7500 is the one you need to be concerned about.
Why?
Seventy Seven - going to heaven
Seventy Six - nothing but clicks
Seventy Five - taken alive
Seventy Oh Four - sick on the floor
Geneve said:
I think it’s most often used for practice Pan Pan calls on 121.5 - you have to squark 7700 for a position fix.
Useful practice for both sides.
Although, I’m sure some people announce ‘practice’ when they are actually lost and don’t want to embarrass themselves.
On a flight shortly after June we were asked to to carry out a practice mayday by the home airfield on 121.5. It helps the people at D&D (distress & diversion) keep on top of their skills. Useful practice for both sides.
Although, I’m sure some people announce ‘practice’ when they are actually lost and don’t want to embarrass themselves.
A good friend had use for them a few years back when his chart fell out of his flexwing
Geneve said:
I think it’s most often used for practice Pan Pan calls on 121.5 - you have to squark 7700 for a position fix.
Useful practice for both sides.
Although, I’m sure some people announce ‘practice’ when they are actually lost and don’t want to embarrass themselves.
I was a passenger in an R44 a few years ago when a practice Pan call turned into a real one when we took a sizeable bird strike into the rotor hub - we were on the ground so quickly that we lost radio communications with the ATC unit before they could work out quite what was going on.Useful practice for both sides.
Although, I’m sure some people announce ‘practice’ when they are actually lost and don’t want to embarrass themselves.
As an ex-air traffic controller I have had 3 Mayday aircraft call me whilst console. All landed safely, but it focusses the mind. The supervisor will get rid of the other aircraft you are dealing with to allow you to concentrate on one aircraft and clear the frequency so the emergency aircraft is not overloaded, and you need to give them range and bearings, start arranging crash cover at the airfield (a really well drilled procedure and dead easy) and keep everyone updated.
Normally aircraft squawk 7700 (codes are allocated via this list) and transmit on the emergency frequency then the Distress and Diversion cell (D&D) get an auto triangulated position and start assisting the pilot, handing over to the ATC agency that will get the ac on the ground. Mine were aircraft already on frequency.
I also witnessed an undercarriage collapse; the pilot could not get the gear down properly so we knew what was coming; they flew around and burnt off enough fuel (too low to dump but the burn rate was high with the gear partially deployed) and the crash crews chased the aircraft down the runway and were at the aircraft as it slewed to a stop.
Normally aircraft squawk 7700 (codes are allocated via this list) and transmit on the emergency frequency then the Distress and Diversion cell (D&D) get an auto triangulated position and start assisting the pilot, handing over to the ATC agency that will get the ac on the ground. Mine were aircraft already on frequency.
I also witnessed an undercarriage collapse; the pilot could not get the gear down properly so we knew what was coming; they flew around and burnt off enough fuel (too low to dump but the burn rate was high with the gear partially deployed) and the crash crews chased the aircraft down the runway and were at the aircraft as it slewed to a stop.
Edited by Julietbravo on Monday 18th October 15:22
Julietbravo said:
I also witnessed an undercarriage collapse; the pilot could not get the gear down properly so we knew what was coming; they flew around and burnt off enough fuel (too low to dump but the burn rate was high with the gear partially deployed) and the crash crews chased the aircraft down the runway and were at the aircraft as it slewed to a stop.
Virgin A340 LHR 90's? Edited by Julietbravo on Monday 18th October 15:22
I'm surprised there are so many daily occurrences. I consider it as a Mayday, but also one where you don't have the chance to make a radio call.
I'm sure our ATC colleagues can confirm but I've been taught that it's possible that ATC will not necessarily require you to change to 7700 after declaring a Mayday?
I'm sure our ATC colleagues can confirm but I've been taught that it's possible that ATC will not necessarily require you to change to 7700 after declaring a Mayday?
For people interested this is a really interesting interview of the chap who was the ATC supervisor when Speedbird 38 (the BA 777) crashed at Heathrow.
Part 1 - http://airlinepilotguy.com/adam-spink-and-speedbir...
Part 2 - http://airlinepilotguy.com/adam-spink-and-speedbir...
There are plenty of interesting other stories by the same chap, and the parent podcast - airlinepilotguy is pretty interesting for enthusiasts.
Part 1 - http://airlinepilotguy.com/adam-spink-and-speedbir...
Part 2 - http://airlinepilotguy.com/adam-spink-and-speedbir...
There are plenty of interesting other stories by the same chap, and the parent podcast - airlinepilotguy is pretty interesting for enthusiasts.
Mabbs9 said:
I'm surprised there are so many daily occurrences. I consider it as a Mayday, but also one where you don't have the chance to make a radio call.
I'm sure our ATC colleagues can confirm but I've been taught that it's possible that ATC will not necessarily require you to change to 7700 after declaring a Mayday?
Correct - if the aircraft is inbound to you, and there is nothing else in the way, the pilot is working hard and changing the code has minimal benefit - why make their life harder by giving them something else to do. You have an direct line to D&D so you can let them know. I'm sure our ATC colleagues can confirm but I've been taught that it's possible that ATC will not necessarily require you to change to 7700 after declaring a Mayday?
It's what's called a conspicuity code - very useful and on the list of things to do in an emergency, but the first thing is always to fly the aircraft.
Mabbs9 said:
I'm surprised there are so many daily occurrences. I consider it as a Mayday, but also one where you don't have the chance to make a radio call.
I'm sure our ATC colleagues can confirm but I've been taught that it's possible that ATC will not necessarily require you to change to 7700 after declaring a Mayday?
It would be unusual in an en route environment not to but as above it would appear at an aerodrome unit there would be limited benefit at a time of already high workload so they’ve taken a pragmatic approach to its use. I can’t think of an occasion where I’ve not used it for a mayday, it’s incredibly effective at letting the numerous sectors and agencies around us that we’re going to be busy and to not call us or bombard us with traffic where at all avoidable. Essentially 7700 means “leave me alone”.I'm sure our ATC colleagues can confirm but I've been taught that it's possible that ATC will not necessarily require you to change to 7700 after declaring a Mayday?
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