Narrative:

Approximately 50 miles southwest of orf at FL390; I noticed it had been silent for a while. After checking the radios and trying to bring up ATC with no luck; we sent an ACARS message to dispatch to see if they could find what frequency we needed to be on. We finally got in contact with the controlling agency; who informed us we had a stuck microphone. After some minor troubleshooting; we still could not figure exactly how that happened. [I suggest we] install a transmit light on the radios.

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Original NASA ASRS Text

Title: B737 First Officer experiences a stuck Mic that goes undetected for a period of time. A new frequency is obtained from Dispatch and radio contact is successfully established.

Narrative: Approximately 50 miles southwest of ORF at FL390; I noticed it had been silent for a while. After checking the radios and trying to bring up ATC with no luck; we sent an ACARS message to Dispatch to see if they could find what frequency we needed to be on. We finally got in contact with the controlling agency; who informed us we had a stuck MIC. After some minor troubleshooting; we still could not figure exactly how that happened. [I suggest we] install a transmit light on the radios.

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.