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FAA to Pilots: Keep Transponders On While Taxiing

Safety Alert for Operators 15006 was published by the FAA last week to ensure that pilots realize the need to keep their aircraft transponders turned on to the altitude-reporting mode even when operational on the ground in airport movement areas. ( More...

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cwhitty07 2
Great! Now i have to disable my traffic system on every startup and after every landing so I don't get continuous aural and visual traffic warnings while taxiing!
James Carlson 1
Indeed. Unintended consequences.
Hank Surface 1
This has been in the AIM for several years but mostly ignored by pilots and instructors.
Wasn't this something that ASDE-X was supposed to alleviate, at least at most major airports?
The issue is pilots not turning it on, or operating in Mode C.
I thought Transponder Mode S was the solution for the transponder querying traffic (so that it could basically be "always on")?
bbabis 1
Many avionics installations use WOW switches or speed sensors to automatically put the transponders in STBY on the ground no matter what position the function switch is in. Sometimes overriding this is user selectable but an avionics shop may need to make the change.
Ralph Rios 1
This is exactly right. I have the "new" style of modern, digital transponder. It senses when my airspeed exceeds a certain threshold and only then does it turn on to ALT reporting. To meet this mandate, I'd need to manually override after every startup AND landing, or figure out how to reprogram this setting.
James Carlson 1
The only WOW switch I've got is for my beacon. I replaced the original incandescent with an LED-based one, and, wow, that sucker is bright. ;-}
Sounds like the programmers of the ASDE-X decided that altitude is a component required for proper tracking. That new system must be dropping transponders not providing all expected information, regardless of how trivial.
It's not the system, it's pilots not turning the transponder on, or operating in in Mode C.
James Carlson 2
That might be the problem, but that's not what the SAFO says. It doesn't distinguish S vs C at all. Instead, it says that we need to have the transponder on and in "altitude reporting" mode when in a movement area.

I still have no Mode S, so I'll follow the SAFO by enabling Mode C before taxi. It probably doesn't help, but shouldn't hurt. And it'd be nice if the SAFO were more detailed about the specific requirements.

I think that complying with rules is certainly easier if I know the rationale.
bbabis 3
Rationale? That is never to be known or discussed. You are not to reason why; you are but to do and fly.
Paul Smith 1
The rationale? You can't handle the rationale!
bbabis 0
Even better!
It seems that this is being read wrong. At ASDE-X airports, the airport chart says to operate with alt. reporting. During the past year or so, it has been recommended to operate in the on position at all other airports. Since there has been some non-compliance at ASDE-X airports, it seems that they want the transponders on at all airports now.
James Carlson 1
Read wrong how? I see nothing in the SAFO that specifies any different procedures based on installed equipment or on the airport capabilities. I'd certainly be willing to act differently, but I do need to have my nose rubbed in it. What are you saying that I am reading wrong?

Or are you saying that the SAFO is written in a way that's ambiguous and is almost certain to cause more confusion due to the wide variance of equippage in the world? If so, then I agree.


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