What Reason Would A Pilot Have To Turn Off The Transponder In The Plane He Was Flying?

[sandyRoe]

If there's no g9d reason why have a switch to do it?

[237SJ]

There`s a switch to do everything on an aircraft - On, Off, Armed. They have to be set to the appropriate setting before flight.

[Buenchico]

Any electrical equipment (e,g. your computer or TV set) carries with it a slight risk of component failure, leading to a possibility of fire through overheating or erratic functioning (e.g. a transponder that keeps 'squawking' incorrect identification codes, confusing air traffic controllers).

So, in the event of such component failure, it would seem sensible to be able to turn the defective device off.

(Well, that's my theory anyway but Clanad will probably know better!)

[Peter Pedant]

You dont want to turn the engines off in flight do you
but there is still a switch to do it

[vulcan42]

I believe the switch is there to isolate the transponder when the aircraft are on the runway and taking off and landing, in other words to avoid confusion in the airport area.

[Hopkirk]

If there is a problem with anything in the world, the first thing to try is to switch it off then on again. (except perhaps a life support machine)

You can't do that unless you have a switch.

[Peter Pedant]

Hoppie

you can pull the plug out of the wall ( life support machine )
and that has defintiely been done

as with an anaesthetic machine whilst it is being used to anaesthetise a patient

( people are trained to cope with that sort of thing -
use T piece and 02 to hand ventilate patient just in case you were wondering what )

[Hopkirk]

I stand corrected.

[sandyRoe]

I was thinking of the Malaysian plane in the Indian Ocean. Taking the control of the transponder away from a pilot in case he switched it off and then ditched in the vastness of the sea was probably never a consideration.