Narrative:

We were cleared for takeoff from teb via the runway 19 dalton departure. After takeoff the pilot is to maintain VFR; fly runway heading to 800 ft; then turn right to 280 degree heading and maintain 1300 ft until cleared to climb. After takeoff; I reduced power and upon completing the turn to 280 degrees; I engaged the autoplt climbing at 350 ft per minute. Both the co-pilot and myself called 'altitude capture' as per sops and observed the flashing 'altitude capture' annunciation on the ADI's. Seconds after confirming altitude capture; I glanced at the altimeter again and realized the aircraft was still climbing. The 'altitude capture' annunciation had disappeared and was now replaced with a 300 FPM climb rate annunciation. I immediately pushed the nose over; stopping the climb at 1400 ft and descended back to 1300 ft. As I stopped the climb; ny called saying they showed us at 1500 ft. This was the busiest time of the flight; and neither the co-pilot nor myself can identify for certain what happened to cause this. Possible explanations may be: 1) the autoplt pitch control knob may have been bumped after altitude capture. 2) the flight director V/south button may have been accidentally depressed after altitude capture. 3) an unfortunate 'glitch' with the autoplt; malfunctioning at just the wrong time. Reviewing the dalton departure after the flight; I realized for the first time that the altitude assignment reads; 'maintain VFR at or below 1300 ft.' in the future I plan to set the altitude alerter to 1200 ft instead of 1300 ft to prevent this problem.

Related reports:

Google
 

Original NASA ASRS Text

Title: A FALCON 20 ON THE TEB DALTON DEP EXCEEDED THE INITIAL LEVEL OFF ALT WHEN THE AUTOPLT FAILED TO CAPTURE 1300 FT.

Narrative: WE WERE CLRED FOR TAKEOFF FROM TEB VIA THE RWY 19 DALTON DEP. AFTER TAKEOFF THE PLT IS TO MAINTAIN VFR; FLY RWY HEADING TO 800 FT; THEN TURN R TO 280 DEG HEADING AND MAINTAIN 1300 FT UNTIL CLRED TO CLB. AFTER TAKEOFF; I REDUCED PWR AND UPON COMPLETING THE TURN TO 280 DEGS; I ENGAGED THE AUTOPLT CLBING AT 350 FT PER MINUTE. BOTH THE CO-PLT AND MYSELF CALLED 'ALTITUDE CAPTURE' AS PER SOPS AND OBSERVED THE FLASHING 'ALTITUDE CAPTURE' ANNUNCIATION ON THE ADI'S. SECONDS AFTER CONFIRMING ALTITUDE CAPTURE; I GLANCED AT THE ALTIMETER AGAIN AND REALIZED THE ACFT WAS STILL CLBING. THE 'ALTITUDE CAPTURE' ANNUNCIATION HAD DISAPPEARED AND WAS NOW REPLACED WITH A 300 FPM CLB RATE ANNUNCIATION. I IMMEDIATELY PUSHED THE NOSE OVER; STOPPING THE CLB AT 1400 FT AND DSNDED BACK TO 1300 FT. AS I STOPPED THE CLB; NY CALLED SAYING THEY SHOWED US AT 1500 FT. THIS WAS THE BUSIEST TIME OF THE FLT; AND NEITHER THE CO-PLT NOR MYSELF CAN IDENTIFY FOR CERTAIN WHAT HAPPENED TO CAUSE THIS. POSSIBLE EXPLANATIONS MAY BE: 1) THE AUTOPLT PITCH CTL KNOB MAY HAVE BEEN BUMPED AFTER ALTITUDE CAPTURE. 2) THE FLT DIRECTOR V/S BUTTON MAY HAVE BEEN ACCIDENTALLY DEPRESSED AFTER ALTITUDE CAPTURE. 3) AN UNFORTUNATE 'GLITCH' WITH THE AUTOPLT; MALFUNCTIONING AT JUST THE WRONG TIME. REVIEWING THE DALTON DEP AFTER THE FLT; I REALIZED FOR THE FIRST TIME THAT THE ALT ASSIGNMENT READS; 'MAINTAIN VFR AT OR BELOW 1300 FT.' IN THE FUTURE I PLAN TO SET THE ALTITUDE ALERTER TO 1200 FT INSTEAD OF 1300 FT TO PREVENT THIS PROB.

Data retrieved from NASA's ASRS site as of January 2009 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.