Narrative:

During a normal and regular flight from atl, GA, to cancun, mexico, on nov/xa/98, flying on an md-83 of a charter air carrier, we were climbing to our final cleared altitude of FL330 when we received a request from ATC to reach FL330 in 2 mins or less. At that point we were about FL295 with a rate of climb of 1300 FPM to 1500 FPM. The speed we use for normal climb is 290 KTS to approximately FL270 and .72 mach from there to whatever the cruise altitude will be. So we had .72 mach at the time we received the request and I increased the rate of climb reducing the mach number to mach .70, acquiring a good rate to comply with ATC request. We reached FL330 with mach .70 and started to experience light and occasional moderate turbulence at that altitude affecting considerably the performance of the aircraft. Few mins later, we were cleared to fly direct to an intersection ahead on the route. The turn worsened the condition, making it impossible to hold the airspeed, and we started to drop down fast. At that point we made several and desperate attempts with ATC to descend to a lower altitude, but unfortunately there was traffic affecting our descent. I saw how the airspeed was dropping low and at the first chance I advised ATC that we were unable to hold the altitude and we were leaving FL330 to FL280. Just before we started the descent, the aircraft came into one approach to stall and other came on few seconds later. At that time we were already descending and airspeed began to recuperate. We had control of the airplane all the time, but I think that if we would have stayed more time at that altitude a very bad situation would have happened. Now I understand that I made a great mistake accepting a request that has to be answered immediately, considering that we have to check on the best rate of climb speed, turbulence reports, and many other factors involving the security of the flight that may take more than 2 mins to check on. Also, the communication with ATC could have been more clear and precise of what was going on in addition to the turbulence. I am truly very concerned of what happened to me that day and I learned that no matter how professional you are or how experienced you are, quick decisions are never easy to make.

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Original NASA ASRS Text

Title: FLC OF AN MD83 EXCEEDED THE ACFT PERFORMANCE LIMITATIONS AS A RESULT OF INSUFFICIENT AIRSPD AT A HIGH CRUISE ALT CAUSED BY A SLOWER CLB SPD FOR A HIGHER RATE OF CLB TO ASSIGNED ALT. THE ACFT REACTED BY STALL BUFFETING BEFORE REGAINING SUFFICIENT AIRSPD IN AN EMER DSCNT. IN ADDITION, THE ACFT'S WT AND BAL EXCEEDED CTR OF GRAVITY FORWARD LIMIT.

Narrative: DURING A NORMAL AND REGULAR FLT FROM ATL, GA, TO CANCUN, MEXICO, ON NOV/XA/98, FLYING ON AN MD-83 OF A CHARTER ACR, WE WERE CLBING TO OUR FINAL CLRED ALT OF FL330 WHEN WE RECEIVED A REQUEST FROM ATC TO REACH FL330 IN 2 MINS OR LESS. AT THAT POINT WE WERE ABOUT FL295 WITH A RATE OF CLB OF 1300 FPM TO 1500 FPM. THE SPD WE USE FOR NORMAL CLB IS 290 KTS TO APPROX FL270 AND .72 MACH FROM THERE TO WHATEVER THE CRUISE ALT WILL BE. SO WE HAD .72 MACH AT THE TIME WE RECEIVED THE REQUEST AND I INCREASED THE RATE OF CLB REDUCING THE MACH NUMBER TO MACH .70, ACQUIRING A GOOD RATE TO COMPLY WITH ATC REQUEST. WE REACHED FL330 WITH MACH .70 AND STARTED TO EXPERIENCE LIGHT AND OCCASIONAL MODERATE TURB AT THAT ALT AFFECTING CONSIDERABLY THE PERFORMANCE OF THE ACFT. FEW MINS LATER, WE WERE CLRED TO FLY DIRECT TO AN INTXN AHEAD ON THE RTE. THE TURN WORSENED THE CONDITION, MAKING IT IMPOSSIBLE TO HOLD THE AIRSPD, AND WE STARTED TO DROP DOWN FAST. AT THAT POINT WE MADE SEVERAL AND DESPERATE ATTEMPTS WITH ATC TO DSND TO A LOWER ALT, BUT UNFORTUNATELY THERE WAS TFC AFFECTING OUR DSCNT. I SAW HOW THE AIRSPD WAS DROPPING LOW AND AT THE FIRST CHANCE I ADVISED ATC THAT WE WERE UNABLE TO HOLD THE ALT AND WE WERE LEAVING FL330 TO FL280. JUST BEFORE WE STARTED THE DSCNT, THE ACFT CAME INTO ONE APCH TO STALL AND OTHER CAME ON FEW SECONDS LATER. AT THAT TIME WE WERE ALREADY DSNDING AND AIRSPD BEGAN TO RECUPERATE. WE HAD CTL OF THE AIRPLANE ALL THE TIME, BUT I THINK THAT IF WE WOULD HAVE STAYED MORE TIME AT THAT ALT A VERY BAD SIT WOULD HAVE HAPPENED. NOW I UNDERSTAND THAT I MADE A GREAT MISTAKE ACCEPTING A REQUEST THAT HAS TO BE ANSWERED IMMEDIATELY, CONSIDERING THAT WE HAVE TO CHK ON THE BEST RATE OF CLB SPD, TURB RPTS, AND MANY OTHER FACTORS INVOLVING THE SECURITY OF THE FLT THAT MAY TAKE MORE THAN 2 MINS TO CHK ON. ALSO, THE COM WITH ATC COULD HAVE BEEN MORE CLR AND PRECISE OF WHAT WAS GOING ON IN ADDITION TO THE TURB. I AM TRULY VERY CONCERNED OF WHAT HAPPENED TO ME THAT DAY AND I LEARNED THAT NO MATTER HOW PROFESSIONAL YOU ARE OR HOW EXPERIENCED YOU ARE, QUICK DECISIONS ARE NEVER EASY TO MAKE.

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.