Narrative:

During climb out from ZZZZ passing approximately 15500 ft the stick shaker activated. Parameters: autoplt #2 engaged. Slats had just been retracted and airspeed was thought to be increasing. We were on the SID. In order to make the required climb gradient and SID altitude restrs; 15000 ft; we climbed out with slats extended and airspeed at 230 KTS. We had changed the climb speed a couple of times as we approached the 15000 ft restr. I was starting to let the aircraft accelerate and the captain said 'be careful we don't want to accelerate too much yet; we'll miss it?' after that input I rolled the speed back to 230 KTS again. After making the restr; I lowered the nose to start accelerating; I called for slat retraction at the sr bug and the captain moved the flap/slat handle. I selected FMS speed and the aircraft continued to accelerate in a shallow climb. The captain was running or had just finished the after takeoff checklist when the stick shaker began. I disconnected the autoplt. I was confused. How could we be getting a stall indication? I was sure the slats had been retracted and that we were accelerating. I noted that the yellow foot was up from the bottom and the yellow 'do not exceed' foot was down from the top. I could not rectify those 2 indications in my mind. I looked at the airspeed and we were accelerating and the stick shaker had stopped. In retrospect; I suspect automatic-slat-extension was trying to prevent a stall and had extended the slats without my noticing. The stick shaker had stopped and the nose was low. It is unknown to me if there was an lsas (low speed autoslat) input. The aircraft quickly accelerated to the do not exceed foot and the aural started saying 'slats overspd.' I began to raise the nose to stop the acceleration and reduce the airspeed. While that was going on the captain put the slat flap lever out then up and the slats retracted and the aurals ceased. We accelerated and climbed. We engaged autoplt #1 and the aircraft flew normally thereafter. There is another restr on the SID I remember looking at that and thinking about whether we would make that restr. I was concerned about the climb requirement and looking at the SID when the stick shaker started. I wonder if I inadvertently selected a speed mode after selecting FMS speed; accelerating and retracting the slats. I do not know that I did that but I may have. This incident was very confusing and happened very quickly. We had a stick shaker and within a few seconds were getting an overspd warning. I was very confused. Factors contributing to the chain of events leading up to this event. A very heavy aircraft (630000 pounds at takeoff); a steep climb in an odd climb out confign and a very contentious pre-departure environment contributed to the stress level in the cockpit. The cockpit discussion was all flight related but not all about this flight. My ability to compartmentalize the other stresses; so that concentration on the tasks at hand could be maintained; may have been compromised. Supplemental information from acn 734091: I was the pm (captain) during climb out. Autoplt #2 was engaged. The aircraft was accelerating after meeting a steep departure gradient. Passing approximately 15500 ft the stick shaker activated. I was alerted to the almost muffled sound of what could have been the stick shaker and the first officer mentioned something of the same. I moved my attentions from paper-sorting and navigating details to first monitoring the engines with an equally quick glance toward the airspeed indicator/ADI/and standby instrument. I only recall seeing what appeared as a band of yellow extending from the top and another from the bottom. What I thought I was seeing was an indication of being too fast and too slow all at the same time. 'A coffin corner at 15000 plus ft.' I tried to reason. Did we have false airspeed indications? Then the aircraft rapidly accelerated to the do not exceed foot and the aural was actually saying 'slats overspd' or was it 'overspd slats.' I am still unsure of the exact order of verbiage used and my first thoughts were centered around a stall condition based on the vibration of the columnand the first officer's comments; yet the airspeed indications were soon to visually cue me to an over-speed condition. As the first officer disconnected the autoplt to ease the nose of the aircraft a bit up from a now lower than desired attitude; the yellow bands began to separate and I recall hearing 'overspd' and seemingly later the call 'slats' from the warning system. During this time I am trying to process the information in the order received. Somehow we were too slow and too fast at the same time; a shallow descent was now being arrested by clicking off the autoplt; yellow airspeed bands nearly touched in the center of the airspeed tape; and a quick flash of red letters in the lower left of the ADI (an area often hidden by the yoke). In between all of the above events; I reached for the slat handle and tugged it aft in an attempt to verify its position and if necessary to extend slats. I again glanced at the standby airspeed in my attempt to quickly understand what the trends were by comparisons of all displayed airspds. I finally reached a confirmation of our airspeed (now 300 KTS and increasing). The warnings ceased; and I verified the slats were stowed. We accelerated and climbed normally thereafter and autoplt #1 was engaged. I made a logbook entry at the end of the exhausting duty day in an attempt to accurately relay what could be recalled to alert those in charge of what we perceived to have happened. Now; after some rest; I suspect automatic-slat-extension was trying to prevent a stall and had extended the slats. Perhaps I simply retracted the slats on command without first verifying the airspeed? Or perhaps this occurred after a pilot commanded (speed intervention) airspeed decrease. (The PF had intervened with several changes earlier; and I did not note such action at the time of the events. It is only speculation on my part.) the aircraft system seemed to have performed as designed. The stick shaker stopped; the nose was low; and the airspeed was increasing. This incident occurred without notice and I was 'out of the flying loop' and well into the secretarial duties of the flight (15000 ft; climbing rapidly). It was very confusing; largely to the short duration of each separate warning/event. We had stick shaker and within a few seconds were getting an overspd warning. Factors contributing to this event: the entire duty period was 'more than stressful' with over 3 hours of my time usually spent on 'normal' preflight and in-flight duties having been derailed and hopelessly 'lost' by having to deal with operational and far conflicts created by a 'surprise' (to us) airworthiness directive; an unrevealed aom maintenance required bulletin; and resultant operational procedure. This was very mentally fatiguing. A heavy aircraft (maximum gross takeoff); a steep climb gradient requirement (6.5%) to a very high altitude; at a new (to me) airport and trip pairing; were also possible contributors. One note: an observation that I should have forwarded upon the first installation of these standby airspeed indicators (on another fleet) is that the airspeed indication 'wheel' moves entirely contrary to what the mind perceives as 'normal.' that is; the wheel spins the wrong way. The installed wheel spins to display increasing airspds further and further left. Every other instrument of measurement that I have ever encountered (thermometers; pressure gauges; speedometers; etc) work opposite to show increasing values; increasing values are shown to the right. This event proves to me that I was correct in my long-held assumption that when most needed; interpretation of this instrument's indications would be very difficult and time consuming.

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Original NASA ASRS Text

Title: THE CREW OF A HEAVY MD11 REPORTS A STALL INDICATION DURING CLB AFTER A HIGH ALT SLAT RETRACT AS THEY ATTEMPTED TO MAKE SID ALT CONSTRAINTS.

Narrative: DURING CLBOUT FROM ZZZZ PASSING APPROX 15500 FT THE STICK SHAKER ACTIVATED. PARAMETERS: AUTOPLT #2 ENGAGED. SLATS HAD JUST BEEN RETRACTED AND AIRSPD WAS THOUGHT TO BE INCREASING. WE WERE ON THE SID. IN ORDER TO MAKE THE REQUIRED CLB GRADIENT AND SID ALT RESTRS; 15000 FT; WE CLBED OUT WITH SLATS EXTENDED AND AIRSPD AT 230 KTS. WE HAD CHANGED THE CLB SPD A COUPLE OF TIMES AS WE APCHED THE 15000 FT RESTR. I WAS STARTING TO LET THE ACFT ACCELERATE AND THE CAPT SAID 'BE CAREFUL WE DON'T WANT TO ACCELERATE TOO MUCH YET; WE'LL MISS IT?' AFTER THAT INPUT I ROLLED THE SPD BACK TO 230 KTS AGAIN. AFTER MAKING THE RESTR; I LOWERED THE NOSE TO START ACCELERATING; I CALLED FOR SLAT RETRACTION AT THE SR BUG AND THE CAPT MOVED THE FLAP/SLAT HANDLE. I SELECTED FMS SPD AND THE ACFT CONTINUED TO ACCELERATE IN A SHALLOW CLB. THE CAPT WAS RUNNING OR HAD JUST FINISHED THE AFTER TKOF CHKLIST WHEN THE STICK SHAKER BEGAN. I DISCONNECTED THE AUTOPLT. I WAS CONFUSED. HOW COULD WE BE GETTING A STALL INDICATION? I WAS SURE THE SLATS HAD BEEN RETRACTED AND THAT WE WERE ACCELERATING. I NOTED THAT THE YELLOW FOOT WAS UP FROM THE BOTTOM AND THE YELLOW 'DO NOT EXCEED' FOOT WAS DOWN FROM THE TOP. I COULD NOT RECTIFY THOSE 2 INDICATIONS IN MY MIND. I LOOKED AT THE AIRSPD AND WE WERE ACCELERATING AND THE STICK SHAKER HAD STOPPED. IN RETROSPECT; I SUSPECT AUTO-SLAT-EXTENSION WAS TRYING TO PREVENT A STALL AND HAD EXTENDED THE SLATS WITHOUT MY NOTICING. THE STICK SHAKER HAD STOPPED AND THE NOSE WAS LOW. IT IS UNKNOWN TO ME IF THERE WAS AN LSAS (LOW SPD AUTOSLAT) INPUT. THE ACFT QUICKLY ACCELERATED TO THE DO NOT EXCEED FOOT AND THE AURAL STARTED SAYING 'SLATS OVERSPD.' I BEGAN TO RAISE THE NOSE TO STOP THE ACCELERATION AND REDUCE THE AIRSPD. WHILE THAT WAS GOING ON THE CAPT PUT THE SLAT FLAP LEVER OUT THEN UP AND THE SLATS RETRACTED AND THE AURALS CEASED. WE ACCELERATED AND CLBED. WE ENGAGED AUTOPLT #1 AND THE ACFT FLEW NORMALLY THEREAFTER. THERE IS ANOTHER RESTR ON THE SID I REMEMBER LOOKING AT THAT AND THINKING ABOUT WHETHER WE WOULD MAKE THAT RESTR. I WAS CONCERNED ABOUT THE CLB REQUIREMENT AND LOOKING AT THE SID WHEN THE STICK SHAKER STARTED. I WONDER IF I INADVERTENTLY SELECTED A SPD MODE AFTER SELECTING FMS SPD; ACCELERATING AND RETRACTING THE SLATS. I DO NOT KNOW THAT I DID THAT BUT I MAY HAVE. THIS INCIDENT WAS VERY CONFUSING AND HAPPENED VERY QUICKLY. WE HAD A STICK SHAKER AND WITHIN A FEW SECONDS WERE GETTING AN OVERSPD WARNING. I WAS VERY CONFUSED. FACTORS CONTRIBUTING TO THE CHAIN OF EVENTS LEADING UP TO THIS EVENT. A VERY HVY ACFT (630000 LBS AT TKOF); A STEEP CLB IN AN ODD CLBOUT CONFIGN AND A VERY CONTENTIOUS PRE-DEP ENVIRONMENT CONTRIBUTED TO THE STRESS LEVEL IN THE COCKPIT. THE COCKPIT DISCUSSION WAS ALL FLT RELATED BUT NOT ALL ABOUT THIS FLT. MY ABILITY TO COMPARTMENTALIZE THE OTHER STRESSES; SO THAT CONCENTRATION ON THE TASKS AT HAND COULD BE MAINTAINED; MAY HAVE BEEN COMPROMISED. SUPPLEMENTAL INFO FROM ACN 734091: I WAS THE PM (CAPT) DURING CLBOUT. AUTOPLT #2 WAS ENGAGED. THE ACFT WAS ACCELERATING AFTER MEETING A STEEP DEP GRADIENT. PASSING APPROX 15500 FT THE STICK SHAKER ACTIVATED. I WAS ALERTED TO THE ALMOST MUFFLED SOUND OF WHAT COULD HAVE BEEN THE STICK SHAKER AND THE FO MENTIONED SOMETHING OF THE SAME. I MOVED MY ATTENTIONS FROM PAPER-SORTING AND NAVING DETAILS TO FIRST MONITORING THE ENGS WITH AN EQUALLY QUICK GLANCE TOWARD THE AIRSPD INDICATOR/ADI/AND STANDBY INST. I ONLY RECALL SEEING WHAT APPEARED AS A BAND OF YELLOW EXTENDING FROM THE TOP AND ANOTHER FROM THE BOTTOM. WHAT I THOUGHT I WAS SEEING WAS AN INDICATION OF BEING TOO FAST AND TOO SLOW ALL AT THE SAME TIME. 'A COFFIN CORNER AT 15000 PLUS FT.' I TRIED TO REASON. DID WE HAVE FALSE AIRSPD INDICATIONS? THEN THE ACFT RAPIDLY ACCELERATED TO THE DO NOT EXCEED FOOT AND THE AURAL WAS ACTUALLY SAYING 'SLATS OVERSPD' OR WAS IT 'OVERSPD SLATS.' I AM STILL UNSURE OF THE EXACT ORDER OF VERBIAGE USED AND MY FIRST THOUGHTS WERE CTRED AROUND A STALL CONDITION BASED ON THE VIBRATION OF THE COLUMNAND THE FO'S COMMENTS; YET THE AIRSPD INDICATIONS WERE SOON TO VISUALLY CUE ME TO AN OVER-SPD CONDITION. AS THE FO DISCONNECTED THE AUTOPLT TO EASE THE NOSE OF THE ACFT A BIT UP FROM A NOW LOWER THAN DESIRED ATTITUDE; THE YELLOW BANDS BEGAN TO SEPARATE AND I RECALL HEARING 'OVERSPD' AND SEEMINGLY LATER THE CALL 'SLATS' FROM THE WARNING SYS. DURING THIS TIME I AM TRYING TO PROCESS THE INFO IN THE ORDER RECEIVED. SOMEHOW WE WERE TOO SLOW AND TOO FAST AT THE SAME TIME; A SHALLOW DSCNT WAS NOW BEING ARRESTED BY CLICKING OFF THE AUTOPLT; YELLOW AIRSPD BANDS NEARLY TOUCHED IN THE CTR OF THE AIRSPD TAPE; AND A QUICK FLASH OF RED LETTERS IN THE LOWER L OF THE ADI (AN AREA OFTEN HIDDEN BY THE YOKE). IN BTWN ALL OF THE ABOVE EVENTS; I REACHED FOR THE SLAT HANDLE AND TUGGED IT AFT IN AN ATTEMPT TO VERIFY ITS POS AND IF NECESSARY TO EXTEND SLATS. I AGAIN GLANCED AT THE STANDBY AIRSPD IN MY ATTEMPT TO QUICKLY UNDERSTAND WHAT THE TRENDS WERE BY COMPARISONS OF ALL DISPLAYED AIRSPDS. I FINALLY REACHED A CONFIRMATION OF OUR AIRSPD (NOW 300 KTS AND INCREASING). THE WARNINGS CEASED; AND I VERIFIED THE SLATS WERE STOWED. WE ACCELERATED AND CLBED NORMALLY THEREAFTER AND AUTOPLT #1 WAS ENGAGED. I MADE A LOGBOOK ENTRY AT THE END OF THE EXHAUSTING DUTY DAY IN AN ATTEMPT TO ACCURATELY RELAY WHAT COULD BE RECALLED TO ALERT THOSE IN CHARGE OF WHAT WE PERCEIVED TO HAVE HAPPENED. NOW; AFTER SOME REST; I SUSPECT AUTO-SLAT-EXTENSION WAS TRYING TO PREVENT A STALL AND HAD EXTENDED THE SLATS. PERHAPS I SIMPLY RETRACTED THE SLATS ON COMMAND WITHOUT FIRST VERIFYING THE AIRSPD? OR PERHAPS THIS OCCURRED AFTER A PLT COMMANDED (SPD INTERVENTION) AIRSPD DECREASE. (THE PF HAD INTERVENED WITH SEVERAL CHANGES EARLIER; AND I DID NOT NOTE SUCH ACTION AT THE TIME OF THE EVENTS. IT IS ONLY SPECULATION ON MY PART.) THE ACFT SYS SEEMED TO HAVE PERFORMED AS DESIGNED. THE STICK SHAKER STOPPED; THE NOSE WAS LOW; AND THE AIRSPD WAS INCREASING. THIS INCIDENT OCCURRED WITHOUT NOTICE AND I WAS 'OUT OF THE FLYING LOOP' AND WELL INTO THE SECRETARIAL DUTIES OF THE FLT (15000 FT; CLBING RAPIDLY). IT WAS VERY CONFUSING; LARGELY TO THE SHORT DURATION OF EACH SEPARATE WARNING/EVENT. WE HAD STICK SHAKER AND WITHIN A FEW SECONDS WERE GETTING AN OVERSPD WARNING. FACTORS CONTRIBUTING TO THIS EVENT: THE ENTIRE DUTY PERIOD WAS 'MORE THAN STRESSFUL' WITH OVER 3 HRS OF MY TIME USUALLY SPENT ON 'NORMAL' PREFLT AND INFLT DUTIES HAVING BEEN DERAILED AND HOPELESSLY 'LOST' BY HAVING TO DEAL WITH OPERATIONAL AND FAR CONFLICTS CREATED BY A 'SURPRISE' (TO US) AIRWORTHINESS DIRECTIVE; AN UNREVEALED AOM MAINT REQUIRED BULLETIN; AND RESULTANT OPERATIONAL PROC. THIS WAS VERY MENTALLY FATIGUING. A HVY ACFT (MAX GROSS TKOF); A STEEP CLB GRADIENT REQUIREMENT (6.5%) TO A VERY HIGH ALT; AT A NEW (TO ME) ARPT AND TRIP PAIRING; WERE ALSO POSSIBLE CONTRIBUTORS. ONE NOTE: AN OBSERVATION THAT I SHOULD HAVE FORWARDED UPON THE FIRST INSTALLATION OF THESE STANDBY AIRSPD INDICATORS (ON ANOTHER FLEET) IS THAT THE AIRSPD INDICATION 'WHEEL' MOVES ENTIRELY CONTRARY TO WHAT THE MIND PERCEIVES AS 'NORMAL.' THAT IS; THE WHEEL SPINS THE WRONG WAY. THE INSTALLED WHEEL SPINS TO DISPLAY INCREASING AIRSPDS FURTHER AND FURTHER L. EVERY OTHER INST OF MEASUREMENT THAT I HAVE EVER ENCOUNTERED (THERMOMETERS; PRESSURE GAUGES; SPEEDOMETERS; ETC) WORK OPPOSITE TO SHOW INCREASING VALUES; INCREASING VALUES ARE SHOWN TO THE R. THIS EVENT PROVES TO ME THAT I WAS CORRECT IN MY LONG-HELD ASSUMPTION THAT WHEN MOST NEEDED; INTERP OF THIS INSTRUMENT'S INDICATIONS WOULD BE VERY DIFFICULT AND TIME CONSUMING.

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.