No Transponder in RVSM Airspace
 

I'm a controller at ZFW. We have been told that an aircraft in RVSM airspace is still RVSM capable if it looses its transponder. The equipment qualifier is an ATC assigned /H . I was under the impression that one of the requirements of operating in RVSM airspace, among many, is TCAS that is approved for RVSM. An aircraft that doesn't have a transponder or Mode C for that matter is invisible to other TCAS equipped aircraft. My question is will the TCAS system still talk to one another even with the transponder inop? Does TCAS get the information on the host aircraft from the transponder or from the Air Data Computer? I argued that the aircraft was no longer RVSM capable without a functioning transponder and mode? Management told me I was wrong.

"The following equipment is required to be operating prior to entering RVSM airspace:
• Two independent primary altimeter systems
• One automatic altitude hold system
• One altitude alerting device
• Transponder (altitude reporting)"

This is cut and pasted right out of our ops manual. And, though it's not listed above, the MEL does say no RVSM if the TCAS is inop. Most RVSM aircraft are going to have two transponders, though. You could "lose one", turn the other one on, and still been okay for RVSM.

I'm talking no transponder at all. In your case both are inop. I say the aircraft is no longer RVSM capable.

"I say the aircraft is no longer RVSM capable."

I agree and both my FAA approved flight ops manual and my FAA approved MEL do, too.

I agree, no longer capable of RVSM. Of course, you could inform ATC and they could make the excpetion time/traffic permitting. But even in that case, you're still not technically RVSM capable. At least that the way I understand it.

Three exception to operating in RVSM airspace without the proper equipment. 1. Lifeguard 2. Military 3. RVSM certification test flights. As far as I know there are no other exception.

They, (ATC), will probably be the first ones to notice that that your transponder is TU. :oThe world is a whole lot prettier at FL280 and below anyway;)
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