Narrative:

I understand we have experienced 2 more high altitude/low speed events in the MD80 fleet in the past month. As a former safety representative; I agree with my colleague that our air carrier does not do a good enough job of closing the loop between real-world safety events and our training and procedures. I have suggested a training/checklist solution to low-speed MD80 events in the past; and have been ignored. I do so again here. My experience is that most crews do not pay close enough attention to the critical moments after leveloff. A short 30-60 second check after leveloff can quickly identify most all autothrottle; EPR system; aircraft weight; aircraft loading; other autoflt system; engine sync system; etc; problems that can lead to low speed events. I conduct such a check after each leveloff at initial cruise or climb to higher altitude. In essence; what we are doing is verifying the performance we expect when we consult the altitude capability chart before climbing. After leveloff; I check to see that engine power is stable; at or near the expected EPR 'and' N1 predicted by aircraft performance charts or 'perf.' sometimes; power is not stable because of a sync system problem. A procedure exists for troubleshooting this situation in the QRH. I have found almost no MD80 first officer's who are aware of its existence. Very; very few first officer's pay attention to MD80 power and autothrottle operation immediately after leveloff; in my view. Aircraft overweight; aircraft misloading resulting in instability; EPR probe problems; autothrottle problems; and the like will all manifest as unstable power; with excessive excursion; oscillation; instability; or excessive split between engines. The crew can then elect the proper remedy; such as terminating engine sync operation; applying engine heat; terminating use of autothrottles; or descending to a lower altitude. In my view; the addition of a cruise checklist item such as 'engine power/performance check' and proper training of such an item; would eliminate or at least vastly reduce MD80 low speed events. It would also serve as an excellent simulator training discussion item as it touches on several aircraft system.

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Original NASA ASRS Text

Title: MD80 CAPTAIN EXPRESSES POSSIBLE SOLUTION TO THE HIGH ALTITUDE LOW AIRSPEED EVENTS THAT HAVE BEEN OCCURRING IN THE FLEET.

Narrative: I UNDERSTAND WE HAVE EXPERIENCED 2 MORE HIGH ALT/LOW SPD EVENTS IN THE MD80 FLEET IN THE PAST MONTH. AS A FORMER SAFETY REPRESENTATIVE; I AGREE WITH MY COLLEAGUE THAT OUR ACR DOES NOT DO A GOOD ENOUGH JOB OF CLOSING THE LOOP BTWN REAL-WORLD SAFETY EVENTS AND OUR TRAINING AND PROCS. I HAVE SUGGESTED A TRAINING/CHKLIST SOLUTION TO LOW-SPD MD80 EVENTS IN THE PAST; AND HAVE BEEN IGNORED. I DO SO AGAIN HERE. MY EXPERIENCE IS THAT MOST CREWS DO NOT PAY CLOSE ENOUGH ATTN TO THE CRITICAL MOMENTS AFTER LEVELOFF. A SHORT 30-60 SECOND CHK AFTER LEVELOFF CAN QUICKLY IDENT MOST ALL AUTOTHROTTLE; EPR SYS; ACFT WT; ACFT LOADING; OTHER AUTOFLT SYS; ENG SYNC SYS; ETC; PROBS THAT CAN LEAD TO LOW SPD EVENTS. I CONDUCT SUCH A CHK AFTER EACH LEVELOFF AT INITIAL CRUISE OR CLB TO HIGHER ALT. IN ESSENCE; WHAT WE ARE DOING IS VERIFYING THE PERFORMANCE WE EXPECT WHEN WE CONSULT THE ALT CAPABILITY CHART BEFORE CLBING. AFTER LEVELOFF; I CHK TO SEE THAT ENG PWR IS STABLE; AT OR NEAR THE EXPECTED EPR 'AND' N1 PREDICTED BY ACFT PERFORMANCE CHARTS OR 'PERF.' SOMETIMES; PWR IS NOT STABLE BECAUSE OF A SYNC SYS PROB. A PROC EXISTS FOR TROUBLESHOOTING THIS SITUATION IN THE QRH. I HAVE FOUND ALMOST NO MD80 FO'S WHO ARE AWARE OF ITS EXISTENCE. VERY; VERY FEW FO'S PAY ATTN TO MD80 PWR AND AUTOTHROTTLE OP IMMEDIATELY AFTER LEVELOFF; IN MY VIEW. ACFT OVERWT; ACFT MISLOADING RESULTING IN INSTABILITY; EPR PROBE PROBS; AUTOTHROTTLE PROBS; AND THE LIKE WILL ALL MANIFEST AS UNSTABLE PWR; WITH EXCESSIVE EXCURSION; OSCILLATION; INSTABILITY; OR EXCESSIVE SPLIT BTWN ENGS. THE CREW CAN THEN ELECT THE PROPER REMEDY; SUCH AS TERMINATING ENG SYNC OP; APPLYING ENG HEAT; TERMINATING USE OF AUTOTHROTTLES; OR DSNDING TO A LOWER ALT. IN MY VIEW; THE ADDITION OF A CRUISE CHKLIST ITEM SUCH AS 'ENG PWR/PERFORMANCE CHK' AND PROPER TRAINING OF SUCH AN ITEM; WOULD ELIMINATE OR AT LEAST VASTLY REDUCE MD80 LOW SPD EVENTS. IT WOULD ALSO SERVE AS AN EXCELLENT SIMULATOR TRAINING DISCUSSION ITEM AS IT TOUCHES ON SEVERAL ACFT SYS.

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.