The aircraft was being flown to retirement at the 309th Aerospace Maintenance and Regeneration Group, the US military aircraft storage facility at Davis–Monthan Air Force Base, Arizona. The aircraft was in its initial climb out of Savannah/Hilton Head International Airport, when it went into a left bank before losing altitude and crashing. Eyewitnesses have reported that the aircraft appeared unstable after takeoff, and that one engine was shut down during the flight. The aircraft impacted on Augusta Road, then a fire ignited that destroyed the entire airframe, apart from the tail. All personnel on board the aircraft were killed, but nobody on the ground was killed or injured as a result of the accident. A video of the accident was recorded by a nearby surveillance camera. The accident investigation was within the jurisdiction of the active duty United States Air Force, which assembled an investigation board.
Aftermath
As a precautionary measure, the governor of Puerto Rico, Ricardo Rosselló, ordered all WC-130 aircraft to remain grounded until the conclusion of the accident investigation. The governor also ordered an assessment of the WC-130 fleet in the Puerto Rico Air National Guard. Additionally, commanders of the active duty USAF were directed to observe a one-day pause in operations, to review and identify potential safety concerns that may lead to mishaps. A section of highway 21 at the impact site was closed immediately after the accident, and the Air National Guard provided funds to the United States Army Corps of Engineers for repairs and cleanup. Traffic was diverted around the crash site to adjacent road SR 307 through a temporary detour, until the completion of repairs. The closed section of highway 21 was reopened for public use on June 8, 2018. The aircraft’s wreckage was recovered and moved to a storage facility in Joint Base Charleston, South Carolina by mid-May.
Investigation
The investigation carried out by the USAF found the root cause of the crash to be pilots error following an engine malfunction. During the takeoff roll, engine number 1 experienced performance fluctuations which went unnoticed until after takeoff. The engine power dropped from nearly to under 300, causing the aircraft to pull to the left, nearly departing the runway. The investigation found that the takeoff should have been aborted but was not. Furthermore, the investigation determined that the flight crew had failed to adequately prepare for emergency actions, and the maintenance technicians failed to properly diagnose and repair the malfunctioning engine before flight. After the flight crew retracted the landing gear, they identified that engine No.1 was malfunctioning but did not perform the takeoff continued after engine failure procedure or follow the engine shutdown checklist, nor did they complete the after takeoff checklist. The flaps had been set to 50% for takeoff and were not retracted. The approved method of manoeuvring a multi engine aircraft in such a situation is to bank the aircraft so that the malfunctioning engine is on the high-side wing. In this case, the pilot incorrectly applied left bank and rudder, instead of banking to the right. At an air speed of 131 knots this combination ultimately led to a left wing stall resulting in a loss of control. The maximum altitude was, which was insufficient to regain control of the aircraft.
