Large Transport
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance
Flight Crew Rejected Takeoff; Flight Crew Returned To Gate
Human Factors
While operating the flight controls as PF (Pilot Flying); and beginning the takeoff roll; after brake release; as power was applied and throttles passed through approximately 10;000 ft-lb torque; the Captain/Pilot Monitoring and I simultaneously heard and felt a 'thud' which we immediately interpreted as a possible load shift. The Captain called for a rejected takeoff which we conducted in accordance with company procedures. We taxied back to the ramp; parked and shut down all engines. All hands conducted an inspection of the load. The skid load consisting of approximately eight long steel drill pipes; approx 15 feet long by 18 inches in diameter appeared to have shifted approximately two linear feet aft from the original loaded position. (Caused by) inadequate securing of cargo skid load; suspected due to improperly affixed and/or inadequate number of aft securing straps and/or chains.
On takeoff roll a noise was heard and felt in the cockpit.  The takeoff was rejected and the aircraft returned to the ramp for evaluation.  Upon examination it was determined that a portion of the cargo had shifted aft. Insufficient aft restraint on the affected portion of the cargo.
Air carrier flight crew reported rejecting the takeoff after hearing a load shift at power application.