PLT OF AN AMATEUR BUILT LONG EZ WAS PREVENTED FROM CLBING ABOVE 500 FT AGL AFTER TKOF DUE TO THE SPD BRAKE EXTENDING AND THE CABLE BECOMING DISCONNECTED FOR RETRACTION. THE SPD BRAKE BLOCKED ENG COOLING SO ADDITIONAL AIRSPD IN LEVEL FLT WAS NECESSARY TO FORCE THE SPD BRAKE TO RETRACT.

Narrative

ON THE AFTERNOON OF DEC/XA/98; ABOUT XA00; I TOOK OFF FROM JEFFERSON COUNTY ARPT (BJC) FOR A SHORT FLT TO LONGMONT (2V2). DURING THE TKOF ROLL OR CLBOUT; THE SPD BRAKE ON MY LONG EZ DEPLOYED; THE RETRACT CABLE DISCONNECTED. THE CLBOUT WAS REDUCED; BUT AT FIRST I THOUGHT IT WAS THE TURB AND DOWNWASH FROM THE MOUNTAINS JUST TO THE W. BY THE TIME I FIGURED WHAT WAS WRONG; THE CYLINDER HEAD AND OIL TEMPS WERE REALLY GOING UP. THE SPD BRAKE BLOCKS MOST OF THE COOLING AIR FLOW IN A CLB. I LEVELED OFF AT ABOUT 500 FT AGL TO TRY AND ACCELERATE TO GET THE TEMPS DOWN AND TO GET THE SPD BRAKE TO BLOW BACK UP TO THE RETRACTED POS. TO TURN BACK TO BJC WOULD HAVE PUT ME OVER A MORE POPULATED AREA; SO I CONTINUED OVER THE LEAST POPULATED AREA AHEAD AND THAT ALSO TOOK ME TOWARD LOWER TERRAIN. IN A FEW MINS; I WAS ABLE TO SPD UP AND THE BOARD RETRACTED AND THE TEMPS WENT BACK TO NORMAL. NO MORE PROBS DURING THE FLT TO LONGMONT. I WAS NEVER BELOW 500 FT AGL; BUT FOR A SHORT WHILE I MIGHT HAVE BEEN OVER OTHER THAN A SPARSELY POPULATED AREA. I HOPE THIS DID NOT CAUSE AN INCONVENIENCE TO ANYONE. I AM NOW IN THE PROCESS OF REBUILDING THE RETRACT SYS FOR THE SPD BRAKE SO THIS PROB SHOULD NOT HAPPEN AGAIN.