Pilot of a small transport was distraction and failed to hear ATC instructions to climb resulting in...

Attributes
ACN	288173
Time
Date	199411
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : saf
State Reference	NM
Altitude	msl bound lower : 11000 msl bound upper : 13000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Route In Use	enroute airway : v263
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 60 flight time total : 6000 flight time type : 60
ASRS Report	288173
Person 2
Affiliation	Other
Function	observation : passenger
Qualification	other other : other
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

En route mry to dpa, fuel stop at 11H. Passing saf I became aware of a strange 'clicking' sound. Determined it was not airframe or engine, investigated radios. Turned each off momentarily, no luck. Finally determined problem caused by a headset microphone a passenger had removed and hung up while napping. Vibration caused microphone to occasionally strike the hard shell of the headset phones thereby making a sound and breaking squelch. I then noticed I had neglected to switch back on the radio I was working center. I called center, center said they had been trying to reach me, that I was 'well below' MEA: climb to 13000 ft, because of excellent WX I had the terrain in sight and was safely above it. Thoughts: I was probably 'off the air' several mins due to momentarily forgetting to switch the radio back on: not hard to do when preoccupied with an unusual problem. While the problem and its solution did not seem threatening, I probably should have informed center what I was doing. Because of good WX, there was no danger, but center could not know this.

Original NASA ASRS Text

Title: PLT OF A SMT WAS DISTR AND FAILED TO HEAR ATC INSTRUCTIONS TO CLB RESULTING IN AN ALT WELL BELOW THE MEA.

Narrative: ENRTE MRY TO DPA, FUEL STOP AT 11H. PASSING SAF I BECAME AWARE OF A STRANGE 'CLICKING' SOUND. DETERMINED IT WAS NOT AIRFRAME OR ENG, INVESTIGATED RADIOS. TURNED EACH OFF MOMENTARILY, NO LUCK. FINALLY DETERMINED PROB CAUSED BY A HEADSET MIKE A PAX HAD REMOVED AND HUNG UP WHILE NAPPING. VIBRATION CAUSED MIKE TO OCCASIONALLY STRIKE THE HARD SHELL OF THE HEADSET PHONES THEREBY MAKING A SOUND AND BREAKING SQUELCH. I THEN NOTICED I HAD NEGLECTED TO SWITCH BACK ON THE RADIO I WAS WORKING CTR. I CALLED CTR, CTR SAID THEY HAD BEEN TRYING TO REACH ME, THAT I WAS 'WELL BELOW' MEA: CLB TO 13000 FT, BECAUSE OF EXCELLENT WX I HAD THE TERRAIN IN SIGHT AND WAS SAFELY ABOVE IT. THOUGHTS: I WAS PROBABLY 'OFF THE AIR' SEVERAL MINS DUE TO MOMENTARILY FORGETTING TO SWITCH THE RADIO BACK ON: NOT HARD TO DO WHEN PREOCCUPIED WITH AN UNUSUAL PROB. WHILE THE PROB AND ITS SOLUTION DID NOT SEEM THREATENING, I PROBABLY SHOULD HAVE INFORMED CTR WHAT I WAS DOING. BECAUSE OF GOOD WX, THERE WAS NO DANGER, BUT CTR COULD NOT KNOW THIS.

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.

Pilot of a small transport was distraction and failed to hear ATC instructions to climb resulting in an altitude well below the MEA.