Takeoff without clearance.

Attributes
ACN	139254
Time
Date	199003
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : mkg
State Reference	MI
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	climbout : takeoff
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 40 flight time total : 2600
ASRS Report	139254
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : non radar
Events
Anomaly	aircraft equipment problem : less severe incursion : runway other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	Pilot Deviation

Narrative:

Took off west/O clearance. Advised by departure control. No action taken. No evasive action required. No landing aircraft. Caused by misunderstanding tower, I thought I was cleared. I have had radio problems and plane has been in several times in last 3 months to correct them. This was first flight to test most recent repairs. When the headset boom microphone is plugged in, there has been a tendency to block out all reception from 5 to 10 mins after engine start. Avionics people went on a test flight with me 2 weeks ago and believe they identified the problem (a ground) and corrected it. Departure control advised I was transmitting on one frequency and receiving on another. With the audio switch panel configured for the 'both' switch off and the other in 'automatic' this should not happen. It will be checked out again thoroughly before next flight.

Original NASA ASRS Text

Title: TKOF WITHOUT CLRNC.

Narrative: TOOK OFF W/O CLRNC. ADVISED BY DEP CTL. NO ACTION TAKEN. NO EVASIVE ACTION REQUIRED. NO LNDG ACFT. CAUSED BY MISUNDERSTANDING TWR, I THOUGHT I WAS CLRED. I HAVE HAD RADIO PROBS AND PLANE HAS BEEN IN SEVERAL TIMES IN LAST 3 MONTHS TO CORRECT THEM. THIS WAS FIRST FLT TO TEST MOST RECENT REPAIRS. WHEN THE HEADSET BOOM MIKE IS PLUGGED IN, THERE HAS BEEN A TENDENCY TO BLOCK OUT ALL RECEPTION FROM 5 TO 10 MINS AFTER ENG START. AVIONICS PEOPLE WENT ON A TEST FLT WITH ME 2 WKS AGO AND BELIEVE THEY IDENTIFIED THE PROB (A GND) AND CORRECTED IT. DEP CTL ADVISED I WAS TRANSMITTING ON ONE FREQ AND RECEIVING ON ANOTHER. WITH THE AUDIO SWITCH PANEL CONFIGURED FOR THE 'BOTH' SWITCH OFF AND THE OTHER IN 'AUTO' THIS SHOULD NOT HAPPEN. IT WILL BE CHKED OUT AGAIN THOROUGHLY BEFORE NEXT FLT.

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.