Narrative:

Following an IMC descent to visual conditions, significant turbulence was encountered. Apparently as I was tuning my radio from approach control frequency to ground control frequency, I must have accidentally bumped the selector frequency switch from tower, which had previously cleared me to land on runway 29. I was about 4 mi out when cleared to land. I heard no further radio traffic. After rollout, I reached to switch to ground and discovered that I was already on that frequency. I contacted ground prior to the intersection of runway 7/25 and requested back taxi on runway 25. Ground approved that and instructed me to turn left on taxiway a. I was distracted by an aircraft in position on runway 25 and missed taxiway a. Ground instructed me to make an immediate left turn on the next taxiway, which I did. During taxi to the FBO, ground instructed me to call the tower on the telephone. I called immediately. I was asked if I heard the tower instruct me to roll out past runway 7/25 and exit at taxiway G. I said, 'negative' and told them that I had somehow been on ground control frequency shortly after I was cleared to land. I apologized for missing taxiway a. This incident resulted from 1) poor ergonomic design of the radio control head. In this case, I think I bumped the frequency selector switch during turbulence or bumped it as I selected the next standby frequency. 2) as a result of being off frequency (tower) I did not hear my post landing instructions and did not know an aircraft was in position on runway 25. If I knew that, I would not have been looking to determine his intentions and would have made my turn on taxiway a. Contributing factors: I was distracted by the emt and nurse on the intercom. Single pilot operations. Corrective actions: far 135 air ambulance operations should be mandated by FARS to be 2 pilot operations -- period! I am a retired military pilot with 4 jet type ratings. This type flying is the most demanding/dangerous I have ever done. Normally, I always have the third radio tuned to the tower, today too many things were going on and I didn't. It could have cost more than a phone call to the tower!

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Original NASA ASRS Text

Title: PLT FAILS TO COMPLY WITH TWR INSTRUCTIONS FOR CLRING THE RWY AFTER LNDG.

Narrative: FOLLOWING AN IMC DSCNT TO VISUAL CONDITIONS, SIGNIFICANT TURB WAS ENCOUNTERED. APPARENTLY AS I WAS TUNING MY RADIO FROM APCH CTL FREQ TO GND CTL FREQ, I MUST HAVE ACCIDENTALLY BUMPED THE SELECTOR FREQ SWITCH FROM TWR, WHICH HAD PREVIOUSLY CLRED ME TO LAND ON RWY 29. I WAS ABOUT 4 MI OUT WHEN CLRED TO LAND. I HEARD NO FURTHER RADIO TFC. AFTER ROLLOUT, I REACHED TO SWITCH TO GND AND DISCOVERED THAT I WAS ALREADY ON THAT FREQ. I CONTACTED GND PRIOR TO THE INTXN OF RWY 7/25 AND REQUESTED BACK TAXI ON RWY 25. GND APPROVED THAT AND INSTRUCTED ME TO TURN L ON TXWY A. I WAS DISTRACTED BY AN ACFT IN POS ON RWY 25 AND MISSED TXWY A. GND INSTRUCTED ME TO MAKE AN IMMEDIATE L TURN ON THE NEXT TXWY, WHICH I DID. DURING TAXI TO THE FBO, GND INSTRUCTED ME TO CALL THE TWR ON THE TELEPHONE. I CALLED IMMEDIATELY. I WAS ASKED IF I HEARD THE TWR INSTRUCT ME TO ROLL OUT PAST RWY 7/25 AND EXIT AT TXWY G. I SAID, 'NEGATIVE' AND TOLD THEM THAT I HAD SOMEHOW BEEN ON GND CTL FREQ SHORTLY AFTER I WAS CLRED TO LAND. I APOLOGIZED FOR MISSING TXWY A. THIS INCIDENT RESULTED FROM 1) POOR ERGONOMIC DESIGN OF THE RADIO CTL HEAD. IN THIS CASE, I THINK I BUMPED THE FREQ SELECTOR SWITCH DURING TURB OR BUMPED IT AS I SELECTED THE NEXT STANDBY FREQ. 2) AS A RESULT OF BEING OFF FREQ (TWR) I DID NOT HEAR MY POST LNDG INSTRUCTIONS AND DID NOT KNOW AN ACFT WAS IN POS ON RWY 25. IF I KNEW THAT, I WOULD NOT HAVE BEEN LOOKING TO DETERMINE HIS INTENTIONS AND WOULD HAVE MADE MY TURN ON TXWY A. CONTRIBUTING FACTORS: I WAS DISTRACTED BY THE EMT AND NURSE ON THE INTERCOM. SINGLE PLT OPS. CORRECTIVE ACTIONS: FAR 135 AIR AMBULANCE OPS SHOULD BE MANDATED BY FARS TO BE 2 PLT OPS -- PERIOD! I AM A RETIRED MIL PLT WITH 4 JET TYPE RATINGS. THIS TYPE FLYING IS THE MOST DEMANDING/DANGEROUS I HAVE EVER DONE. NORMALLY, I ALWAYS HAVE THE THIRD RADIO TUNED TO THE TWR, TODAY TOO MANY THINGS WERE GOING ON AND I DIDN'T. IT COULD HAVE COST MORE THAN A PHONE CALL TO THE TWR!

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.