AN SMT TWIN JET EXPERIENCES A RWY EXCURSION AT DED; FL.

Narrative

I MISJUDGED MY FINAL APCH ALT AND AIRSPD AND WAS APCHING A LITTLE FAST AND HIGH. ON SHORT FINAL; I KNEW I WAS A LITTLE HIGH AND FAST BUT THOUGHT I WOULD TOUCH DOWN ABOUT 1/3 OF THE WAY DOWN THE 6000 FT RWY. SHORTLY AFTER PASSING THE THRESHOLD OF THE RWY; I REALIZED THAT IT WOULD BE MORE LIKE ABOUT 1/2 WAY DOWN THE RWY. I DECIDED TO GO AROUND. I STARTED RETRACTING THE SPD BRAKES AND ADVANCED TO FULL THROTTLE A LITTLE TOO FAST. UNFORTUNATELY; THE ENGS HAD DROPPED DOWN TO LOW IN RPM AND COULD NOT TAKE FULL THROTTLE. THEY STARTED TO COMPRESSOR STALL. I REDUCED THROTTLE AND STARTED TO MORE SLOWLY ADD THROTTLE. BY THE TIME I GOT THE SPD BRAKES RETRACTED AND THE ENGS TO ACCEPT FULL THROTTLE; I WAS 2/3 OF THE WAY DOWN THE RWY. THE ACFT WAS STILL SLOWING DOWN BECAUSE THE ENGS HAD NOT FULLY SPOOLED UP; THE FLAPS WERE DOWN AND THE GEAR WAS DOWN. TO START TO CLB I STILL NEEDED TO RETRACT THE FLAPS; WAIT FOR THE ENGS TO GET TO FULL PWR AND ACCELERATE TO CLB SPD. THE TREES AT THE END OF THE RWY WERE GETTING BIG AND I STARTED TO DOUBT THAT I WOULD BE ABLE TO ACCELERATE TO CLB SPD AND CLR THE TREES IN THE DISTANCE L. I DECIDED IT WOULD BE BEST TO MAKE DO WITH WHAT I HAD LEFT IN RWY; WHICH WAS ABOUT 2000 FT. AT THIS POINT I KNEW I COULD NOT STOP IN THE REMAINING RWY; BUT THERE WAS A REASONABLY LONG GRASS OVERRUN AREA. I OVERRAN THE END OF THE RWY BY ABOUT 100 FT. THERE WAS NO DAMAGE TO THE ACFT; OR ANY OTHER PROPERTY AND NO ONE WAS HURT. I HAD 2 OPPORTUNITIES TO AVOID THE SIT. FIRST; I KNEW I WAS NOT STABILIZED ON FINAL APCH GLIDE PATH AT THE PROPER SPD. AT 500 FT AND NOT PROPERLY STABILIZED I SHOULD HAVE DECIDED TO GO AROUND. THERE WAS NO FUEL PROB AND NO NEED TO SALVAGE THE APCH. SECOND; IF I HAD JUST STUCK WITH WHAT I HAD AND TOUCHED DOWN 1/2 WAY DOWN THE RWY; THIS WOULD HAVE LEFT ME 3000 FT TO STOP. WHILE THIS WOULD REQUIRE HARDER THAN NORMAL BRAKING I COULD HAVE EASILY STOPPED BEFORE THE END OF THE RWY. NORMALLY ON APCH; I GET STABILIZED ON GLIDE PATH AND AIRSPD; SET THE ENGS AT 16000-17000 RPM AND CTL AIRSPD WITH SPD BRAKES. IN THIS CONFIGN; THE ENGS CAN ACCEPT IMMEDIATE FULL THROTTLE. I MAINTAIN THIS CONFIGN UNTIL I HAVE THE RWY IS MADE SO GARS ARE NOT MUCH OF A PROB. BECAUSE I WAS HIGH AND FAST ON THIS APCH; I HAD PULLED THE ENGS BACK TO IDLE. I WAS BUSY WITH SALVAGING THE APCH AND FAILED TO KEEP IN MIND THAT THE ENGS WILL TAKE MUCH LONGER THAN NORMAL TO SPOOL UP. THIS ACFT TAKES LONGER THAN MOST TO EXECUTE MISSED APCHS. THIS IS BECAUSE ENG SPOOL UP TIMES; THE NEED TO MODULATE THROTTLES AS ENGS SPOOL UP; ALL CTLS ARE HYD AND THEY DO NOT RESPOND VERY QUICKLY. FIRST YOU NEED TO RETRACT THE SPD BRAKES; THEN THE FLAPS; AND FINALLY THE LNDG GEAR. THE FLAPS ARE CTLED BY THE L-HAND AND YOU NEED TO HAVE YOUR HAND ON THE SWITCH THE ENTIRE TIME THE FLAPS ARE RETRACTING. THUS YOU CANNOT BE CTLING THE THROTTLES AND FLAPS AT THE SAME TIME. MISSED APCHS MUST BE PLANNED AND COMMENCED EARLIER THAN MOST ACFT. I STARTED MISSED APCH PROCS TOO LATE.