Narrative:

While climbing through FL250 for FL290 the aircraft loss IAS and started to approach a stall condition as the aircraft was banked in a turn. Just prior ATC cleared our flight direct to a waypoint that was not loaded into the INS's (inertial navigation system). Being the PNF, I was asked by the captain to load the new waypoint into the 3 INS units. The pilot flying had reduced IAS to 290 KTS in order to increase the rate of climb to meet a crossing restr. The so had the master flight plan which I needed to get the latitude/longitude to put into the INS units. I retrieved the flight plan and inserted the latitude/longitude into the INS units. This procedure took about 1 1/2 mins. At this time I felt a vibration beginning in the aircraft. I looked to the flight instruments and noticed that the IAS had decreased to about 250 KTS and the captain (PF) was increasing thrust to the engines and decreasing the pitch attitude of the aircraft. The altitude of the aircraft descended from FL249 to FL244. I called ATC and advised the controller of this and said that we were now climbing to FL290.

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Original NASA ASRS Text

Title: SPD DETERIORATED ON CLB WHEN PF, CAPT, INCREASED CLB RATE TO MAKE XING RESTR. FO, WHO WAS 'HEAD DOWN' LOADING A WAYPOINT FELT ACFT VIBRATION AND LOOKED AT INSTS JUST AS CAPT WAS ADDING PWR AND LOWERING NOSE.

Narrative: WHILE CLBING THROUGH FL250 FOR FL290 THE ACFT LOSS IAS AND STARTED TO APCH A STALL CONDITION AS THE ACFT WAS BANKED IN A TURN. JUST PRIOR ATC CLRED OUR FLT DIRECT TO A WAYPOINT THAT WAS NOT LOADED INTO THE INS'S (INERTIAL NAV SYS). BEING THE PNF, I WAS ASKED BY THE CAPT TO LOAD THE NEW WAYPOINT INTO THE 3 INS UNITS. THE PLT FLYING HAD REDUCED IAS TO 290 KTS IN ORDER TO INCREASE THE RATE OF CLB TO MEET A XING RESTR. THE SO HAD THE MASTER FLT PLAN WHICH I NEEDED TO GET THE LATITUDE/LONGITUDE TO PUT INTO THE INS UNITS. I RETRIEVED THE FLT PLAN AND INSERTED THE LATITUDE/LONGITUDE INTO THE INS UNITS. THIS PROC TOOK ABOUT 1 1/2 MINS. AT THIS TIME I FELT A VIBRATION BEGINNING IN THE ACFT. I LOOKED TO THE FLT INSTS AND NOTICED THAT THE IAS HAD DECREASED TO ABOUT 250 KTS AND THE CAPT (PF) WAS INCREASING THRUST TO THE ENGS AND DECREASING THE PITCH ATTITUDE OF THE ACFT. THE ALT OF THE ACFT DSNDED FROM FL249 TO FL244. I CALLED ATC AND ADVISED THE CTLR OF THIS AND SAID THAT WE WERE NOW CLBING TO FL290.

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.