Narrative:

After initial climb to FL350, aircraft performed slow and sluggish. At FL350 we were unable to hold desired speed with cruise EPR set. We advised ATC that we were unable to hold FL350 and requested FL310. We were cleared to FL310 and aircraft was able to perform within limits. Flight operated without further incident to bil. I suspected aircraft was loaded improperly and requested a load audit upon arrival in bil. The total number of bags matched, however, on a saturday afternoon flight to bil, in the fall, we carried approximately 80 passenger, of which 80% were heavily loaded hunters. I personally saw approximately 100 bags/duffel bags unloaded from aft cargo that had to weigh 75-100 pounds each (much greater than the standard 25 pounds). Also loaded with 45 gun cases each at least 60-75 pounds (also much greater than the standard 25 pounds). My best estimate is that the aircraft was at least 10000 pounds overweight for that altitude. I discussed this with dispatch, both while airborne and on the ground, and was advised that this can happen during the hunting season. My recommendation is for some type of procedure to take these hunters and large bags into effect. The ramp personnel in bil also commented that this is an ongoing problem that occurs on all flts to and from bil. This is a serious situation that should be addressed before a serious incident would happen.

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Original NASA ASRS Text

Title: DC9 CREW WAS OVERLOADED BY APPROX 10000 LBS.

Narrative: AFTER INITIAL CLB TO FL350, ACFT PERFORMED SLOW AND SLUGGISH. AT FL350 WE WERE UNABLE TO HOLD DESIRED SPD WITH CRUISE EPR SET. WE ADVISED ATC THAT WE WERE UNABLE TO HOLD FL350 AND REQUESTED FL310. WE WERE CLRED TO FL310 AND ACFT WAS ABLE TO PERFORM WITHIN LIMITS. FLT OPERATED WITHOUT FURTHER INCIDENT TO BIL. I SUSPECTED ACFT WAS LOADED IMPROPERLY AND REQUESTED A LOAD AUDIT UPON ARR IN BIL. THE TOTAL NUMBER OF BAGS MATCHED, HOWEVER, ON A SATURDAY AFTERNOON FLT TO BIL, IN THE FALL, WE CARRIED APPROX 80 PAX, OF WHICH 80% WERE HEAVILY LOADED HUNTERS. I PERSONALLY SAW APPROX 100 BAGS/DUFFEL BAGS UNLOADED FROM AFT CARGO THAT HAD TO WEIGH 75-100 LBS EACH (MUCH GREATER THAN THE STANDARD 25 LBS). ALSO LOADED WITH 45 GUN CASES EACH AT LEAST 60-75 LBS (ALSO MUCH GREATER THAN THE STANDARD 25 LBS). MY BEST ESTIMATE IS THAT THE ACFT WAS AT LEAST 10000 LBS OVERWT FOR THAT ALT. I DISCUSSED THIS WITH DISPATCH, BOTH WHILE AIRBORNE AND ON THE GND, AND WAS ADVISED THAT THIS CAN HAPPEN DURING THE HUNTING SEASON. MY RECOMMENDATION IS FOR SOME TYPE OF PROC TO TAKE THESE HUNTERS AND LARGE BAGS INTO EFFECT. THE RAMP PERSONNEL IN BIL ALSO COMMENTED THAT THIS IS AN ONGOING PROB THAT OCCURS ON ALL FLTS TO AND FROM BIL. THIS IS A SERIOUS SIT THAT SHOULD BE ADDRESSED BEFORE A SERIOUS INCIDENT WOULD HAPPEN.

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.