transponder failure

[uchy]

What are the consequences of a transponder failure? Problems and limitations to consider?
Thanks

[ACMS]

So ATC most likely won't be able to see you on their Radar at all unless they are lucky and still have Primary Radar.

So what do you reckon will happen??

I'd say a lot of talking and a lot bigger separation required......

Equals delay for you and everybody around you.

Followed by headache.......

Followed by a nice cold one in the pub.....

[aterpster]

Commercial airplanes have two.

[wiggy]

Total loss of transponders these days pretty much guarantees ATC will deny you access to large portions of airspace, especially upper airspace, for all the reasons ACMS pointed out....FWIW I'll also add to his/her list the fact that you're also not "visible" on anybody's TCAS....

Hence aterpster's comment that commercial aircraft will have two...

[Skyjob]

Possible block altitude required for flight to operate...
Many states mandating TCAS operative.
Even if your MEL allows dispatch, a check must be made with each and every country passing through to ensure the flight is allowed to enter its sovereign airspace

[underfire]

Usually you get a couple of nice fellows in F-16's on each side to help you find the runway...expect to offload somewhere on the tarmac.

[STBYRUD]

Eurocontrol composed a memo on this earlier this year:
http://www.eurocontrol.int/sites/default/files/publication/files/NetAlert-19.pdf

In short - there is no universal solution to the issue!

[Una Due Tfc]

You won't be allowed in RVSM airspace.

You won't be allowed in areas with SSR coverage only.

You MAY be allowed into procedural airspace (IE Oceanic)

[jmmoric]

In Denmark at least you will be allowed to fly to the nearest airport where the transponder can be fixed - It does require thorough coordination with ATC on when and how.

Not a problem for those of us that are used to procedurel control in a combined radar/procedurel enviroment though ;)

[Jonfra]

Recent example:

28 September 2013 Transponder failure: LOT Polish Airlines Boeing 787-800, registration SP-LRA performing flight LOT41 from Warsaw to Toronto, was descending towards Toronto when approach control directed crew to use another transponder. ATC lost LOT41's tag off radar. Approach queried a minute later and crew responded they had tried the other transponder but received a fail indication.



Aircraft was serviced and turned around for a flight back the same day:



28 September 2013 outbound from Canada Transponder failure: LOT Polish Airlines Boeing 787-800, registration SP-LRA performing LOT42 from Toronto back to Warsaw climbing out of Toronto when crew halted their climb at FL270 due to transponder failure, then decided to continue towards Warsaw at FL270. About 130 nm west-southwest of Keflavik her crew diverted to Iceland.



LOT reported the transponder malfunction prompting Norway to not permit overflight of the aircraft.



Ironically radar data show the Mode-S transponder of the aircraft, including position reporting, worked without flaw throughout the flight but the crew had conflicting indications.