330 transponder
 

Can anyone tell me what the stby mode of the transponder does? If you are at the gate, in auto, does the unit squawk with engines off. I was under the impression that oil pressure was needed.

Standby = idle doing nothing
Auto = on ground mode S only (no A/C), with TCAS on or airborne A/C/S

The reason I ask, the airline I'm working for now selects stby at the gate. The other airline I worked at kept the unit in auto. I'm trying to gather enough information to submit a change to keep the unit in auto for all operations. I was under the impression that the unit would not transmit any data without oil pressure.

I believe it does. Oil pressure not relevant. Makes it useable for ATC in towing etc

Thanks for the input.