Narrative:

During climbout from dfw airport on air carrier flight xx jun/wed/89, the controller issued a clearance to turn to a heading of 300 degree to intercept the dfw 274 degree radial, climb to and maintain 16,000', and maintain 250 KTS until advised. As the first officer and PNF, I proceeded to read back the clearance and program the FMS computer for route, speed, and altitude. The captain selected speed intervention of 250 KTS and heading select to the assigned intercept heading. He also attempted to couple VNAV function of the autoplt but this was not accepted by the autoplt so he used flight level change and speed of 250 KTS to climb to the assigned altitude of 16,000' at 250 KTS (16,000' was selected in the altitude window correctly). He then monitored for traffic and my programming of the FMS. Unfortunately, the autoplt entered an altitude capture mode approaching 10,000' instead of continuing to climb to the selected 16,000'. In addition, the automatic throttle disregarded the 250 KT speed intervention and continued to accelerate. The controller called to ask our speed and as I looked up from the FMS I noticed approximately 330 KTS. I replied 330 KTS slowing to 250 KTS assigned. It should be noted that the climb page on the FMS was programmed for VNAV operation from 1000' AGL up but it also malfunctioned when VNAV was selected at 1000'. At the time of the incident, the 2 of us were given an intercept heading, an altitude change, and a speed restriction. In the process of attempting to accomplish the programming of the FMS, listen for ATC and watch for traffic, the airspeed capture of the automatic throttles was overlooked until the speed approached 330 KTS. Callback conversation with reporter revealed the following: reporter states that he had programmed the FMS for departure but was at the time very busy dealing with ATC vectors and the captain had entered the speed restriction manually into the FMS but the system ignored the restriction and speed increased all the way to the barber pole where that limitation was activated. Many things were taking place at this time and it was difficult for the reporter to say for sure what was happening. The entire event was entered into the maintenance log but the outcome was not known to the reporter. Supplemental information from acn 114194: at no time did the FMC give a warning that it had failed.

Related reports:

Google
 

Original NASA ASRS Text

Title: AIRSPEED DEVIATION FROM ASSIGNED DURING CLIMB.

Narrative: DURING CLIMBOUT FROM DFW ARPT ON ACR FLT XX JUN/WED/89, THE CTLR ISSUED A CLRNC TO TURN TO A HDG OF 300 DEG TO INTERCEPT THE DFW 274 DEG RADIAL, CLIMB TO AND MAINTAIN 16,000', AND MAINTAIN 250 KTS UNTIL ADVISED. AS THE F/O AND PNF, I PROCEEDED TO READ BACK THE CLRNC AND PROGRAM THE FMS COMPUTER FOR ROUTE, SPEED, AND ALT. THE CAPT SELECTED SPEED INTERVENTION OF 250 KTS AND HDG SELECT TO THE ASSIGNED INTERCEPT HDG. HE ALSO ATTEMPTED TO COUPLE VNAV FUNCTION OF THE AUTOPLT BUT THIS WAS NOT ACCEPTED BY THE AUTOPLT SO HE USED FLT LEVEL CHANGE AND SPEED OF 250 KTS TO CLIMB TO THE ASSIGNED ALT OF 16,000' AT 250 KTS (16,000' WAS SELECTED IN THE ALT WINDOW CORRECTLY). HE THEN MONITORED FOR TFC AND MY PROGRAMMING OF THE FMS. UNFORTUNATELY, THE AUTOPLT ENTERED AN ALT CAPTURE MODE APCHING 10,000' INSTEAD OF CONTINUING TO CLIMB TO THE SELECTED 16,000'. IN ADDITION, THE AUTO THROTTLE DISREGARDED THE 250 KT SPEED INTERVENTION AND CONTINUED TO ACCELERATE. THE CTLR CALLED TO ASK OUR SPEED AND AS I LOOKED UP FROM THE FMS I NOTICED APPROX 330 KTS. I REPLIED 330 KTS SLOWING TO 250 KTS ASSIGNED. IT SHOULD BE NOTED THAT THE CLIMB PAGE ON THE FMS WAS PROGRAMMED FOR VNAV OPERATION FROM 1000' AGL UP BUT IT ALSO MALFUNCTIONED WHEN VNAV WAS SELECTED AT 1000'. AT THE TIME OF THE INCIDENT, THE 2 OF US WERE GIVEN AN INTERCEPT HEADING, AN ALT CHANGE, AND A SPEED RESTRICTION. IN THE PROCESS OF ATTEMPTING TO ACCOMPLISH THE PROGRAMMING OF THE FMS, LISTEN FOR ATC AND WATCH FOR TFC, THE AIRSPEED CAPTURE OF THE AUTO THROTTLES WAS OVERLOOKED UNTIL THE SPEED APCHED 330 KTS. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: REPORTER STATES THAT HE HAD PROGRAMMED THE FMS FOR DEP BUT WAS AT THE TIME VERY BUSY DEALING WITH ATC VECTORS AND THE CAPT HAD ENTERED THE SPEED RESTRICTION MANUALLY INTO THE FMS BUT THE SYSTEM IGNORED THE RESTRICTION AND SPEED INCREASED ALL THE WAY TO THE BARBER POLE WHERE THAT LIMITATION WAS ACTIVATED. MANY THINGS WERE TAKING PLACE AT THIS TIME AND IT WAS DIFFICULT FOR THE REPORTER TO SAY FOR SURE WHAT WAS HAPPENING. THE ENTIRE EVENT WAS ENTERED INTO THE MAINT LOG BUT THE OUTCOME WAS NOT KNOWN TO THE REPORTER. SUPPLEMENTAL INFORMATION FROM ACN 114194: AT NO TIME DID THE FMC GIVE A WARNING THAT IT HAD FAILED.

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