Narrative:

On jul/xa/95 I was the first officer of service from dfw to hou (AT72 aircraft). My position was that of PNF for this leg. Captain was in command as PIC as well as the PF. This was our second leg coming off a reduced rest period -- with even less rest after the hotel was 45 mins late picking us up at the airport the night before. Our position was approximately 60 NM north of navasota VOR (tnv) at 15000 ft. ZHU cleared us to cross marit intersection at 9000 ft at our discretion. 6 NM past tnv VOR on the struk 8 arrival. At 15 DME north of tnv VOR, I asked captain maybe he would want to begin his descent (to make the restr). Upon realizing how close we were (about 21 NM) he quickly agreed and put the autoplt into a descent mode. At this time I began to get busy with PNF duties of getting ATIS, calling inbound company, reviewing the arrival route. Descending through 10000 ft I also switched on landing light and sterile cockpit light (normal procedure) and proceeded to remove the approach plate for VOR DME runway 22 at hou. ZHU then switched us to houston approach. I began to check in with approach by saying 'houston approach, X with you descending through 7.5...' I paused knowing something was very wrong. As I scanned the entire instrument panel to assess the situation I realized captain had us in a 3000 FPM descent without resetting the altitude selector. It still read 15000 ft. The autoplt had been put into a 3000 FPM descent with no pre- selected altitude. 'Where the hell are we going...?' were my next words. He immediately selected the autoplt off, added power and proceeded to climb back to our assigned altitude. I conveyed the fact that we were assigned 9000 ft. He asked me to verify the altitude -- I did with approach. After about 2 mins houston approach said...'X you're supposed to be at 9000 ft.' by this time captain had recovered and leveled off at 9000 ft so my response was, 'roger, we are level at 9000 ft.' the flight continued without further incident or event.

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Original NASA ASRS Text

Title: FLC DSNDS THROUGH ASSIGNED ALT.

Narrative: ON JUL/XA/95 I WAS THE FO OF SVC FROM DFW TO HOU (AT72 ACFT). MY POS WAS THAT OF PNF FOR THIS LEG. CAPT WAS IN COMMAND AS PIC AS WELL AS THE PF. THIS WAS OUR SECOND LEG COMING OFF A REDUCED REST PERIOD -- WITH EVEN LESS REST AFTER THE HOTEL WAS 45 MINS LATE PICKING US UP AT THE ARPT THE NIGHT BEFORE. OUR POS WAS APPROX 60 NM N OF NAVASOTA VOR (TNV) AT 15000 FT. ZHU CLRED US TO CROSS MARIT INTXN AT 9000 FT AT OUR DISCRETION. 6 NM PAST TNV VOR ON THE STRUK 8 ARR. AT 15 DME N OF TNV VOR, I ASKED CAPT MAYBE HE WOULD WANT TO BEGIN HIS DSCNT (TO MAKE THE RESTR). UPON REALIZING HOW CLOSE WE WERE (ABOUT 21 NM) HE QUICKLY AGREED AND PUT THE AUTOPLT INTO A DSCNT MODE. AT THIS TIME I BEGAN TO GET BUSY WITH PNF DUTIES OF GETTING ATIS, CALLING INBOUND COMPANY, REVIEWING THE ARR RTE. DSNDING THROUGH 10000 FT I ALSO SWITCHED ON LNDG LIGHT AND STERILE COCKPIT LIGHT (NORMAL PROC) AND PROCEEDED TO REMOVE THE APCH PLATE FOR VOR DME RWY 22 AT HOU. ZHU THEN SWITCHED US TO HOUSTON APCH. I BEGAN TO CHK IN WITH APCH BY SAYING 'HOUSTON APCH, X WITH YOU DSNDING THROUGH 7.5...' I PAUSED KNOWING SOMETHING WAS VERY WRONG. AS I SCANNED THE ENTIRE INST PANEL TO ASSESS THE SIT I REALIZED CAPT HAD US IN A 3000 FPM DSCNT WITHOUT RESETTING THE ALT SELECTOR. IT STILL READ 15000 FT. THE AUTOPLT HAD BEEN PUT INTO A 3000 FPM DSCNT WITH NO PRE- SELECTED ALT. 'WHERE THE HELL ARE WE GOING...?' WERE MY NEXT WORDS. HE IMMEDIATELY SELECTED THE AUTOPLT OFF, ADDED PWR AND PROCEEDED TO CLB BACK TO OUR ASSIGNED ALT. I CONVEYED THE FACT THAT WE WERE ASSIGNED 9000 FT. HE ASKED ME TO VERIFY THE ALT -- I DID WITH APCH. AFTER ABOUT 2 MINS HOUSTON APCH SAID...'X YOU'RE SUPPOSED TO BE AT 9000 FT.' BY THIS TIME CAPT HAD RECOVERED AND LEVELED OFF AT 9000 FT SO MY RESPONSE WAS, 'ROGER, WE ARE LEVEL AT 9000 FT.' THE FLT CONTINUED WITHOUT FURTHER INCIDENT OR EVENT.

Data retrieved from NASA's ASRS site as of July 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.