Originally Posted by
Raptor71
If I want to speak to my colleague without using the PTT with on my CW, is it possible?
Yes, with the ACP in I/C there is a open channel between the pair of you.
Problem is the fact that if you forget to turn it off after you finished using it, the channel remains open for all that plug in to listen to, including any ground staff plugged into the I/C outside the aircraft. Also, when it is selected, it mutes the speaker volume, thus on ground it makes sense to turn on speaker, as if a too large volume needs selecting on the ACP the most likely cause is an I/C switch on on of the installed ACP's being selected.
With the ACP PTT in I/C position, what will happen if I use the MIC position on the CW?
The MIC will override the ACP selected I/C, thus you can keep the channel open while responding to ATC.
( same question if instead I use the INT position)?
If I/C is selected, INT need not be used.
If I/C is deselected (e.g. during pushback) INT allows communication with external connected ground staff, inside flight deck you would need to speak up a bit louder to avoid having I/C selected and ground staff to hear all you checklist items and responses.
IF ACP PTT is used in R/T ( which is not spring loaded), I understand It allows me to transmit on any frequency without using the PTT sw on the CW.
The ACP PTT is identical to the function of the CW PTT. You transmit on the selected ACP function.