Narrative:

After flying an aircraft with the new hot mic switch; I can see a few problems that might arise with the switch placement. I think that by putting the switch on the yoke could cause problems with missed communications; either with ATC or crew. When you place the switch in the hot mic position; it enables a continuous communication between the flight crew; which is great. However; when a call is received from ATC; you have to either use the ptt switch; hand mic; or control switch. Most people use the control wheel switch; especially during takeoff and landing which enables them to have the other hand free near the console; in order to change frequencies; altitude; flaps; gear; etc. When I would try to transmit using the control wheel switch; I had to override the hot mic switch and would over apply pressure; which would cause me to transmit; thus blocking out ATC and disabling the hot mic position during a critical phase of flight. I think the best place to put a hot mic switch would be on the push to talk switch on the center console. If you could lock the intercom into the hot position; it would allow continuous communication within the cockpit and enable pilots to use either hand mic or control wheel transmit switch at their discretion without a lapse of communication between the crew members during the approach and departure phase when the control wheel transmit switch is used most often. In essence; you could avoid missed communications; the blocking of ATC instructions; and have a continuous open communication between the pilots during the most critical portion of the flight without any possibilities of mistakes that may arise.

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Original NASA ASRS Text

Title: An air carrier first officer believes the hot microphone switch on the control yoke would be more appropriately located on the center console.

Narrative: After flying an aircraft with the new hot mic switch; I can see a few problems that might arise with the switch placement. I think that by putting the switch on the yoke could cause problems with missed communications; either with ATC or Crew. When you place the switch in the hot mic position; it enables a continuous communication between the flight Crew; which is great. However; when a call is received from ATC; you have to either use the PTT switch; hand mic; or control switch. Most people use the control wheel switch; especially during takeoff and landing which enables them to have the other hand free near the console; in order to change frequencies; altitude; flaps; gear; etc. When I would try to transmit using the control wheel switch; I had to override the hot mic switch and would over apply pressure; which would cause me to transmit; thus blocking out ATC and disabling the hot mic position during a critical phase of flight. I think the best place to put a hot mic switch would be on the Push To Talk switch on the center console. If you could lock the intercom into the hot position; it would allow continuous communication within the cockpit and enable Pilots to use either hand mic or control wheel transmit switch at their discretion without a lapse of communication between the Crew Members during the approach and departure phase when the control wheel transmit switch is used most often. In essence; you could avoid missed communications; the blocking of ATC instructions; and have a continuous open communication between the Pilots during the most critical portion of the flight without any possibilities of mistakes that may arise.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.