Pilot of vintage tail dragger without starter was handpropping aircraft with only the left main whee...

Attributes
ACN	121375
Time
Date	198908
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : 2w6
State Reference	MD
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 Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Plan	None
Aircraft 2
Make Model Name	Small Aircraft
Flight Phase	ground : parked
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot oversight : pic
Qualification	pilot : private
Experience	flight time last 90 days : 17 flight time total : 305 flight time type : 33
ASRS Report	121375
Events
Anomaly	aircraft equipment problem : less severe conflict : ground critical non adherence : far other anomaly
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Consequence	other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

My airplane is a vintage small aircraft tail dragger and is not equipped with a starter. During preflight, I untied the airplane and left a chock in front of the left main wheel. I was alone during this incident. As soon as the engine started, the RPM increased to well above idle although the throttle control in the cockpit was definitely at the idle position. The airplane jumped the chock and began a turn to the left. My airplane hit another airplane before I could get to the cockpit and secure the engine. No one was injured. The cause of the high RPM at engine start was as follows. Earlier in the day I had removed the engine cowling to take measurements for a new throttle cable. I noticed that the clamp which secures the throttle cable was loosening and I tightened the clamp. The cable must have slipped forward, however, so that when the throttle control in the cockpit was at the idle position, the throttle arm on the carburetor was well above the idle position. My contributions to this incident were not having the airplane tied down for starting and not having an a&P mechanic inspect the throttle linkage after I noticed that the clamp was loosening.

Original NASA ASRS Text

Title: PLT OF VINTAGE TAIL DRAGGER WITHOUT STARTER WAS HANDPROPPING ACFT WITH ONLY THE LEFT MAIN WHEEL CHOCKED, RESULTING IN RUNAWAY ACFT WHICH DAMAGED ANOTHER PARKED ACFT.

Narrative: MY AIRPLANE IS A VINTAGE SMA TAIL DRAGGER AND IS NOT EQUIPPED WITH A STARTER. DURING PREFLT, I UNTIED THE AIRPLANE AND LEFT A CHOCK IN FRONT OF THE LEFT MAIN WHEEL. I WAS ALONE DURING THIS INCIDENT. AS SOON AS THE ENGINE STARTED, THE RPM INCREASED TO WELL ABOVE IDLE ALTHOUGH THE THROTTLE CONTROL IN THE COCKPIT WAS DEFINITELY AT THE IDLE POSITION. THE AIRPLANE JUMPED THE CHOCK AND BEGAN A TURN TO THE LEFT. MY AIRPLANE HIT ANOTHER AIRPLANE BEFORE I COULD GET TO THE COCKPIT AND SECURE THE ENGINE. NO ONE WAS INJURED. THE CAUSE OF THE HIGH RPM AT ENGINE START WAS AS FOLLOWS. EARLIER IN THE DAY I HAD REMOVED THE ENGINE COWLING TO TAKE MEASUREMENTS FOR A NEW THROTTLE CABLE. I NOTICED THAT THE CLAMP WHICH SECURES THE THROTTLE CABLE WAS LOOSENING AND I TIGHTENED THE CLAMP. THE CABLE MUST HAVE SLIPPED FORWARD, HOWEVER, SO THAT WHEN THE THROTTLE CONTROL IN THE COCKPIT WAS AT THE IDLE POSITION, THE THROTTLE ARM ON THE CARBURETOR WAS WELL ABOVE THE IDLE POSITION. MY CONTRIBUTIONS TO THIS INCIDENT WERE NOT HAVING THE AIRPLANE TIED DOWN FOR STARTING AND NOT HAVING AN A&P MECHANIC INSPECT THE THROTTLE LINKAGE AFTER I NOTICED THAT THE CLAMP WAS LOOSENING.

Data retrieved from NASA's ASRS site as of August 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 vintage tail dragger without starter was handpropping aircraft with only the left main wheel chocked, resulting in runaway aircraft which damaged another parked aircraft.