Narrative:

The problem was discovered on takeoff roll just after takeoff thrust was set. The cockpit indications were a large airframe vibration and noise. The captain decided to reject the takeoff and the noise and vibration stopped. At first we thought it was a tire problem, but the taxi back to the ramp was a smooth ride. Next we surmised that there was a cargo canister in the cargo area and it had come loose even though the load manifest showed the aircraft was empty of cargo. The problem arose because maintenance was performed on the aircraft that needed a ballast pallet to be placed in the main cargo hold on one of the forward stations, and subsequently the ballast pallet was not removed before flight. The pallet is a flat piece of metal that was placed on the cargo deck floor with a slab of concrete on it. I was told the concrete slab weighed about 7400 pounds. On takeoff roll, the concrete slab slid off the metal pallet, rolled the length of the cargo deck and wedged itself into the tail section of the airplane. It punched a hole in the fuselage and probably caused other internal damage that I couldn't see upon post flight. One of the contributing factors to this incident are maintenance procedures not being fully completed and the documentation saying that it was. If the maintenance procedure was properly completed, then the ballast pallet would have been removed. If the documentation was done properly, then the aircraft would not have been dispatched for flight as it still had an unsecured ballast pallet inside of it. Another contributing factor is the load manifest. The load manifest showed that all cargo stations of the main cargo deck were empty, when in fact there was a pallet with a concrete slab in one of the forward main cargo position. This situation could possibly have been a lot worse. What if the ballast pallet had started rolling down the cargo hold at takeoff rotation? Would it have gone all the way through the airplane taking out the control lines, hydraulic lines, and other important parts of the airplane? Even if it would not have, would this radical aft shift in center of gravity still have allowed the aircraft to be controllable? One other plausible consideration is if the aircraft had gotten airborne the slab of concrete could also have rolled forward in landing roll during braking, compromising the crew cabin, possibly injuring or killing the crew. As for corrective action, we should ensure maintenance is properly completed before it is documented complete, and the load manifest should also be visually verified correct by the load-master before flight. Supplemental information from acn 344022: weight and balance indicated a void aircraft and doors were closed when crew arrived. Maintenance had the weight in place while performing an engine change and forgot it after work was complete. No logbook entry had been made for the ballast.

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Original NASA ASRS Text

Title: B757 FREIGHTER TKOF ABORTED WHEN UNKNOWN CARGO, BALLAST, SHIFTS AND SLIDES TO REAR OF ACFT.

Narrative: THE PROB WAS DISCOVERED ON TKOF ROLL JUST AFTER TKOF THRUST WAS SET. THE COCKPIT INDICATIONS WERE A LARGE AIRFRAME VIBRATION AND NOISE. THE CAPT DECIDED TO REJECT THE TKOF AND THE NOISE AND VIBRATION STOPPED. AT FIRST WE THOUGHT IT WAS A TIRE PROB, BUT THE TAXI BACK TO THE RAMP WAS A SMOOTH RIDE. NEXT WE SURMISED THAT THERE WAS A CARGO CANISTER IN THE CARGO AREA AND IT HAD COME LOOSE EVEN THOUGH THE LOAD MANIFEST SHOWED THE ACFT WAS EMPTY OF CARGO. THE PROB AROSE BECAUSE MAINT WAS PERFORMED ON THE ACFT THAT NEEDED A BALLAST PALLET TO BE PLACED IN THE MAIN CARGO HOLD ON ONE OF THE FORWARD STATIONS, AND SUBSEQUENTLY THE BALLAST PALLET WAS NOT REMOVED BEFORE FLT. THE PALLET IS A FLAT PIECE OF METAL THAT WAS PLACED ON THE CARGO DECK FLOOR WITH A SLAB OF CONCRETE ON IT. I WAS TOLD THE CONCRETE SLAB WEIGHED ABOUT 7400 LBS. ON TKOF ROLL, THE CONCRETE SLAB SLID OFF THE METAL PALLET, ROLLED THE LENGTH OF THE CARGO DECK AND WEDGED ITSELF INTO THE TAIL SECTION OF THE AIRPLANE. IT PUNCHED A HOLE IN THE FUSELAGE AND PROBABLY CAUSED OTHER INTERNAL DAMAGE THAT I COULDN'T SEE UPON POST FLT. ONE OF THE CONTRIBUTING FACTORS TO THIS INCIDENT ARE MAINT PROCS NOT BEING FULLY COMPLETED AND THE DOCUMENTATION SAYING THAT IT WAS. IF THE MAINT PROC WAS PROPERLY COMPLETED, THEN THE BALLAST PALLET WOULD HAVE BEEN REMOVED. IF THE DOCUMENTATION WAS DONE PROPERLY, THEN THE ACFT WOULD NOT HAVE BEEN DISPATCHED FOR FLT AS IT STILL HAD AN UNSECURED BALLAST PALLET INSIDE OF IT. ANOTHER CONTRIBUTING FACTOR IS THE LOAD MANIFEST. THE LOAD MANIFEST SHOWED THAT ALL CARGO STATIONS OF THE MAIN CARGO DECK WERE EMPTY, WHEN IN FACT THERE WAS A PALLET WITH A CONCRETE SLAB IN ONE OF THE FORWARD MAIN CARGO POS. THIS SIT COULD POSSIBLY HAVE BEEN A LOT WORSE. WHAT IF THE BALLAST PALLET HAD STARTED ROLLING DOWN THE CARGO HOLD AT TKOF ROTATION? WOULD IT HAVE GONE ALL THE WAY THROUGH THE AIRPLANE TAKING OUT THE CTL LINES, HYD LINES, AND OTHER IMPORTANT PARTS OF THE AIRPLANE? EVEN IF IT WOULD NOT HAVE, WOULD THIS RADICAL AFT SHIFT IN CTR OF GRAVITY STILL HAVE ALLOWED THE ACFT TO BE CONTROLLABLE? ONE OTHER PLAUSIBLE CONSIDERATION IS IF THE ACFT HAD GOTTEN AIRBORNE THE SLAB OF CONCRETE COULD ALSO HAVE ROLLED FORWARD IN LNDG ROLL DURING BRAKING, COMPROMISING THE CREW CABIN, POSSIBLY INJURING OR KILLING THE CREW. AS FOR CORRECTIVE ACTION, WE SHOULD ENSURE MAINT IS PROPERLY COMPLETED BEFORE IT IS DOCUMENTED COMPLETE, AND THE LOAD MANIFEST SHOULD ALSO BE VISUALLY VERIFIED CORRECT BY THE LOAD-MASTER BEFORE FLT. SUPPLEMENTAL INFO FROM ACN 344022: WT AND BAL INDICATED A VOID ACFT AND DOORS WERE CLOSED WHEN CREW ARRIVED. MAINT HAD THE WT IN PLACE WHILE PERFORMING AN ENG CHANGE AND FORGOT IT AFTER WORK WAS COMPLETE. NO LOGBOOK ENTRY HAD BEEN MADE FOR THE BALLAST.

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.