(Last Updated On: July 18, 2018)
Two US C-130 Crashes within One Year - Cases of Bad Machine or Bad Flying?
Only within a short span of one year, two US C-130 crashes took place with both aircraft mysteriously falling from the sky. The C-130 Hercules is by far the most dependable transport military's work-horse for the past six decades. It is not only surprising that these planes crashed in the manner they did but also the fact that the US Air Force and the US Marines have been quite silent about it or tend to be pointing fingers in areas which technically don't make sense.
The 2017-18 crashes came after two years of the last US C-130 Hercules plane crash which took place on Oct. 2, 2015, when a US Air Force C-130 crashed at Jalalabad Airfield in Afghanistan, killing six airmen. The Jalalabad crash was determined in 2016 to be a tragic case of pilot error. Before that, in 2012, another Air Force C-130H crashed in South Dakota while fighting a fire, killing four of the six crew members on board. The pattern is that US continually loses C-130 planes every 2-3 years with significant loss of precious lives.
Let's review the two crashes and build a a more pragmatic picture of possible causes.
Crash No. 1 - Puerto Rico Air National Guard WC-130H - 2 May, 2018
On May 2, 2018, a WC-130H belonging to the Puerto Rico ANG crashed in the US province of Georgia, soon after leaving from Savannah Air National Guard Base. The Hercules slammed against the highway on Georgia State Route 21 at 1126 Hrs (local). The nine manifested crew members could not survive the fatal crash.
The WC-130H plane involved on that ill-fated day was on its last mission pending retirement and final storage at Davis–Monthan Air Force Base, Arizona.
The aircraft immediately after take-off from Savannah Airport was steadily gaining height, when witnesses described that while the aircraft was still at low altitude, itwent into a left bank before losing altitude and crashing. The aircraft smashed at high rate of decent upon the Augusta Road (part of Georgia State Route 21), which resulted in a huge plume of fire ignited that completely disintegrated airframe into hardly recognizable small pieces. Only the tail section of the aircraft remained intact. The last moments of the mishap aircraft were caught on a local webcam footage from a nearby vicinity.
As a precautionary measure, all WC-130H aircraft belonging to the Puerto Rico ANG have been grounded on the order of governor of Puerto Rico, Ricardo Rosselló pending a comprehensive review of the incident and and possible identification of factors that may have potentially contributed to the crash.
Last reports confirmed that the aircraft’s wreckage had been relocated and positioned in a warehouse located at Joint Base Charleston, South Carolina.
Hypothesis No. 1 (Low Altitude Stall)
The video evidence available shows the aircraft in a deep rate of decent indicative of loss of lift i.e. stall, and as the stall aggravated, it was followed by complete loss of control of the aircraft and its attitude. We know that the aircraft stall at a such a low altitude was the reason the airplane crashed. Why the aircraft stalled is the answer one needs to look further. Another incident which comes to mind with a similar low altitude stall was teh C-130J crash in Jalalabad, Afghanistan. See the FDR capture and investigation report below:-
Hypothesis No. 2 (Single/Multi-Engine Failure)
The legacy C-130 airplane is equipped with four turboprop T56 engines capable of producing 4,350 shaft-horsepower each. It's also known that the aircraft was not carrying any significant payload that day, therefore, failure of one or even two engines would not resulted in complete loss of lift. Even in a two-engine failure situation, the steps are given in the Dash-One (Flying Manual) on how to keep the plane airworthy and control the situation.
Hypothesis No. 3 (Extreme Pitch-Up Attitude)
The video footage available only shows the aircraft when it had entered the stall zone, what it does not show are the moments before it, where the attitude of the aircraft may have been such which induced the stall itself. Just after take-off if the aircraft nose was pitched-up to a point where the wings entered the stall zone, it may have been impossible for the crew to recover the aircraft at such low altitude. Following are some of the salient possibilities which may caused the aircraft to pitch-up beyond the normal flight envelope:
(a) Obstruction in Movement of Flight Controls. Any obstruction in the movement of flight controls would have catastrophic results. There have been cases before as well, where some mechanical lock or some object was kept in the control path (linkages/cable etc.) which either the maintenance crew and/or the flight crew forgot to remove prior to take-off. The obstruction may have caused restriction in movement of controls during takeoff leading to an undesired aircraft attitude.
(b) Flight Crew Actions. The pilot or co-pilot, whoever was in-command of the aircraft during take-off, may have inadvertently or advertently pitched the nose up to a point which led to the stall. The intent of such an action may have further ramifications and may warrant a deeper probe of the psychiatric history of the flight crew.
Hypothesis No. 3 (Mechanical Failure)
Another possibility may have been a catastrophic mechanical failure which may be to material fatigue or inappropriate maintenance actions during assembly/rigging of critical flight control systems.
Crash No. 2 - United States Marine Corps KC-130T - 10 July, 2017
The 2017 United States Marine Corps KC-130 crash happened around 4 PM nearby time on Monday, July 10, 2017, when a Lockheed KC-130T Hercules of the United States Marine Corps (USMC) smashed on the ground inverted, following a flat-spin, killing every one of the 16 individuals on the manifest. The airplane was from Marine Aerial Refueler Transport Squadron 452 (VMGR-452) based at Stewart Air National Guard Base, New York. Aircraft wreckage was found in Leflore County, Mississippi.
The Hercules in question was a Lockheed KC-130T Hercules tanker/transport of the United States Marine Corps flying with the nickname "Triple Nuts" due to the imprinted number "000" on its nose.
The aircraft was initially delivered to the United States Air Force in 1993 and later was transferred to the United States Navy and then assigned to the U.S. Marine Corps. It was damaged on the ground during a storm on 1 June 2004 at Naval Air Station Joint Reserve Base Fort Worth, Texas. As a result of the storm, it was flipped onto its port wingtip, damaging a refueling pod. It was quickly repaired and placed back into service.
The accident probably entails a mid-air break up at an altitude around 20,000 feet (6,100 m) while it was flying from Marine Corps Air Station Cherry Point to Naval Air Facility based in El Centro, California. The aircraft came down 85 miles (137 km) in an inverted spin just north of Jackson, Mississippi.
Hypothesis No. 1 (Propeller Blade Separation)
According to limited details available of the investigation report, a propeller blade had separated/ruptured mid-flight from its hub, extensively damaging the fuselage and hitting the engine on the other side. The aircraft was carrying ammunition or explosive material onboard which further aggravated the risk. Propeller separation from the hub or following a complete gearbox failure are known to have happened earlier on the C-130 aircraft. However, in some past instances, the crew had managed to safely land the aircraft, as seen below:-
Hypothesis No. 2 (Structural Failure)
The legacy C-130 airplane has been prone to structural failures in the past, especially its wings. Remembering the Walker California. crash, when a C-130A went down on 17 June 2002, while it was dropping fire retardant material on a 10,000 acre forest fire. near Walker, California. The wings suddenly snapped off and the aircraft crashed near a commercial area. All the 3 crew members were killed.
However, the KC-130T crash presents no such evidence, as the wings can be clearly seen to be intact and attached to the fuselage upon impact (as seen below):
The video evidence available on both the crashes point to probable human lapses in both cases, whereby, the chain of events culminated into the catastrophic events. It is imperative to state that concerned authorities must release investigation findings (preliminary or final) to bring closure to these two events and present answers to the families who lost their loved ones in these two accidents.