Narrative:

While on a vector of 340 degrees at 6000 ft MSL, in contact with ZLA, instrument student under the hood attempted to attain smx ATIS. While doing so, we entered light chop and the student accidentally switched communication #2 to the off position for approximately 90 seconds (or 2 mins). I (the cfii) was watching traffic approach from 3 O'clock low. I noticed no squelch and found the problem and immediately contacted ZLA, at which time I was advised to climb immediately to 8000 ft and proceed direct guadalupe VOR, in VMC conditions. During postflt debrief, we felt that the causes of the incident were the turbulence, cfii inattn to cockpit events while watching for traffic. In the future it would be best to establish crew procedures for keeping each pilot in the loop in order to insure correct selection of cockpit items.

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Original NASA ASRS Text

Title: RADIO COM WAS LOST DURING AN IFR TRAINING FLT AND WAS NOT RECOGNIZED BY THE INSTRUCTOR PLT UNTIL TFC BECAME A FACTOR. THE STUDENT, WHILE UNDER THE HOOD, HAD ACCIDENTALLY SWITCHED THE RADIO OFF WHILE ATTEMPTING TO TUNE ANOTHER RADIO DURING TURB.

Narrative: WHILE ON A VECTOR OF 340 DEGS AT 6000 FT MSL, IN CONTACT WITH ZLA, INST STUDENT UNDER THE HOOD ATTEMPTED TO ATTAIN SMX ATIS. WHILE DOING SO, WE ENTERED LIGHT CHOP AND THE STUDENT ACCIDENTALLY SWITCHED COM #2 TO THE OFF POS FOR APPROX 90 SECONDS (OR 2 MINS). I (THE CFII) WAS WATCHING TFC APCH FROM 3 O'CLOCK LOW. I NOTICED NO SQUELCH AND FOUND THE PROB AND IMMEDIATELY CONTACTED ZLA, AT WHICH TIME I WAS ADVISED TO CLB IMMEDIATELY TO 8000 FT AND PROCEED DIRECT GUADALUPE VOR, IN VMC CONDITIONS. DURING POSTFLT DEBRIEF, WE FELT THAT THE CAUSES OF THE INCIDENT WERE THE TURB, CFII INATTN TO COCKPIT EVENTS WHILE WATCHING FOR TFC. IN THE FUTURE IT WOULD BE BEST TO ESTABLISH CREW PROCS FOR KEEPING EACH PLT IN THE LOOP IN ORDER TO INSURE CORRECT SELECTION OF COCKPIT ITEMS.

Data retrieved from NASA's ASRS site as of July 2007 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.