Narrative:

Editorial type PIC decided to get current after a long period (6 months plus) of flying inactivity. Preflight was unusually lengthy due to airplane being in similar shape as PIC, i.e., all tires were half flat after several months of sitting on the line unflown. Fuel truck had to return to FBO for more air before tires could be filled, and fueler discovered an enormous black widow spider in tire well that had to be extricated before air could be pumped. Then, after engine start, PIC and right seat passenger (a flight instructor) smelled burning and shut down the engine to check for bird nest or other problem, but could discover nothing. We moved the fire extinguisher to back seat so that it would be within easy reach. During runup, 1 magneto ran rough and mixture had to be leaned to correct. By the time we reached the hold line at runway 29, I PIC was anxious to go. We had agreed that my friend the flight instructor would handle communication, but I called tower and asked for takeoff clearance before handing over the microphone. There was no activity at this point in the pattern for runway 29, and my mindset included 2 thoughts: 1) the tower controller would clear us for takeoff, and 2) my friend, being a flight instructor, would back me up on communication. I never did 'hear' what the controller said. The bottom line is that I took off and then heard from the tower after takeoff that we had not been cleared for departure. Other relevant factors: my friend is a little hard of hearing and may not have copied the controller's instructions. We have also flown together so much that I expect her to catch all my mistakes and, at times, am not vigilant enough on my own behalf. Ironically, the last time I flew with her was in her retractable gear plane, with me in the right seat supposed to be backing her up. On 1 touch-and-go we almost had a gear-up because she had forgotten to put the gear down. It was great to get up again, but maybe I'd better find someone meaner to fly with, and vice versa. P.south. I did apologize to the tower later for not listening well enough.

Related reports:

Google
 

Original NASA ASRS Text

Title: UNAUTHORIZED TKOF PERFORMED AFTER RWY INCURSION. UNAUTHORIZED RWY ENTRY OP.

Narrative: EDITORIAL TYPE PIC DECIDED TO GET CURRENT AFTER A LONG PERIOD (6 MONTHS PLUS) OF FLYING INACTIVITY. PREFLT WAS UNUSUALLY LENGTHY DUE TO AIRPLANE BEING IN SIMILAR SHAPE AS PIC, I.E., ALL TIRES WERE HALF FLAT AFTER SEVERAL MONTHS OF SITTING ON THE LINE UNFLOWN. FUEL TRUCK HAD TO RETURN TO FBO FOR MORE AIR BEFORE TIRES COULD BE FILLED, AND FUELER DISCOVERED AN ENORMOUS BLACK WIDOW SPIDER IN TIRE WELL THAT HAD TO BE EXTRICATED BEFORE AIR COULD BE PUMPED. THEN, AFTER ENG START, PIC AND R SEAT PAX (A FLT INSTRUCTOR) SMELLED BURNING AND SHUT DOWN THE ENG TO CHK FOR BIRD NEST OR OTHER PROBLEM, BUT COULD DISCOVER NOTHING. WE MOVED THE FIRE EXTINGUISHER TO BACK SEAT SO THAT IT WOULD BE WITHIN EASY REACH. DURING RUNUP, 1 MAGNETO RAN ROUGH AND MIXTURE HAD TO BE LEANED TO CORRECT. BY THE TIME WE REACHED THE HOLD LINE AT RWY 29, I PIC WAS ANXIOUS TO GO. WE HAD AGREED THAT MY FRIEND THE FLT INSTRUCTOR WOULD HANDLE COM, BUT I CALLED TWR AND ASKED FOR TKOF CLRNC BEFORE HANDING OVER THE MIKE. THERE WAS NO ACTIVITY AT THIS POINT IN THE PATTERN FOR RWY 29, AND MY MINDSET INCLUDED 2 THOUGHTS: 1) THE TWR CTLR WOULD CLR US FOR TKOF, AND 2) MY FRIEND, BEING A FLT INSTRUCTOR, WOULD BACK ME UP ON COM. I NEVER DID 'HEAR' WHAT THE CTLR SAID. THE BOTTOM LINE IS THAT I TOOK OFF AND THEN HEARD FROM THE TWR AFTER TKOF THAT WE HAD NOT BEEN CLRED FOR DEP. OTHER RELEVANT FACTORS: MY FRIEND IS A LITTLE HARD OF HEARING AND MAY NOT HAVE COPIED THE CTLR'S INSTRUCTIONS. WE HAVE ALSO FLOWN TOGETHER SO MUCH THAT I EXPECT HER TO CATCH ALL MY MISTAKES AND, AT TIMES, AM NOT VIGILANT ENOUGH ON MY OWN BEHALF. IRONICALLY, THE LAST TIME I FLEW WITH HER WAS IN HER RETRACTABLE GEAR PLANE, WITH ME IN THE R SEAT SUPPOSED TO BE BACKING HER UP. ON 1 TOUCH-AND-GO WE ALMOST HAD A GEAR-UP BECAUSE SHE HAD FORGOTTEN TO PUT THE GEAR DOWN. IT WAS GREAT TO GET UP AGAIN, BUT MAYBE I'D BETTER FIND SOMEONE MEANER TO FLY WITH, AND VICE VERSA. P.S. I DID APOLOGIZE TO THE TWR LATER FOR NOT LISTENING WELL ENOUGH.

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.