Narrative:

Climbing through about FL260 speed slow light flickered on FMA; I clicked off autopilot and leveled aircraft noticed airspeed approaching 220 with engines normal; vertical velocity indicated 2700 when I clicked off autopilot. Had put autopilot on above 10;000 with speed select set to 300kts. At first could not understand what happened; but I believe at around 17000' when ATC cleared us to higher altitude I had used the vertical speed to continue climb and not confirmed that I had gone back to speed select. This let the aircraft climb at vertical speed instead of at a set speed. I did not confirm I had set speed select for the autopilot ;and to compound the error did not monitor the instruments and mode selected for the a/c.

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Original NASA ASRS Text

Title: An MD80 crew reported that during climb out the First Officer allowed the aircraft to accelerate to 300 kts with a 250 kt restriction. The Speed Select mode was changed to Vertical Speed to slow the aircraft and at FL260 a low speed alert sounded.

Narrative: Climbing through about FL260 speed slow light flickered on FMA; I clicked off autopilot and leveled aircraft noticed airspeed approaching 220 with engines normal; vertical velocity indicated 2700 when I clicked off autopilot. Had put autopilot on above 10;000 with speed select set to 300kts. At first could not understand what happened; but I believe at around 17000' when ATC cleared us to higher altitude I had used the vertical speed to continue climb and not confirmed that I had gone back to speed select. This let the aircraft climb at vertical speed instead of at a set speed. I did not confirm I had set speed select for the autopilot ;and to compound the error did not monitor the instruments and mode selected for the a/c.

Data retrieved from NASA's ASRS site as of April 2012 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.