Narrative:

[I was] taxiing for takeoff on runway xxr. Clearance was to 'cross runway xxl; hold short of xxr'. I crossed runway xxl and as I was setting the parking brake holding short of runway xxr; the parking brake handle came off of the cable in my hand. I thought I was not moving and bent over to the floor to pick up the handle. When I looked back up I had crossed the hold short line onto the edge of the runway. There was no immediate traffic departing or arriving. Ground control asked what happened; and then cleared me across.very frightening episode; as nothing like this has happened to me before. The parking brake arrangement is very poor to begin with ergonomically; but when the handle falls off while applying the brake; it is disconcerting. I was quite confident that I was stationary while retrieving the broken handle and was in shock when I looked back up and realized what happened. Single pilot is certainly not without hazards that don't present themselves when there are two pilots.

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Original NASA ASRS Text

Title: A pilot reports taxiing a Beechcraft BE55 Baron for takeoff and while setting the parking brake to hold short of a crossing runway; the brake 'T' handle came off of the brake cable. After he bent over to the floor to pick up the handle; he realized the aircraft had crossed the hold short line onto the edge of the runway.

Narrative: [I was] taxiing for takeoff on Runway XXR. Clearance was to 'cross Runway XXL; hold short of XXR'. I crossed Runway XXL and as I was setting the parking brake holding short of Runway XXR; the parking brake handle came off of the cable in my hand. I thought I was not moving and bent over to the floor to pick up the handle. When I looked back up I had crossed the hold short line onto the edge of the runway. There was no immediate traffic departing or arriving. Ground Control asked what happened; and then cleared me across.Very frightening episode; as nothing like this has happened to me before. The parking brake arrangement is very poor to begin with ergonomically; but when the handle falls off while applying the brake; it is disconcerting. I was quite confident that I was stationary while retrieving the broken handle and was in shock when I looked back up and realized what happened. Single pilot is certainly not without hazards that don't present themselves when there are two pilots.

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.