The U.S. Air Force has grounded its fleet of stealthy Lockheed Martin F-35 Joint Strike Fighters (JSF) after one aircraft caught fire on takeoff Monday at Eglin Air Force Base in Florida. While the pilot got out of the stricken jet without injury, the roughly $200 million machine could be a total loss.
“The airplane aborted during takeoff due to a fire in the rear of the aircraft, the pilot egressed safely without injury, and the fire was extinguished,” Air Force spokeswoman Maj. Natasha Waggoner told The Daily Beast.
Monday’s fire is one of the most serious incidents suffered by the long-troubled and expensive F-35 program, and it could be the first time an aircraft has been lost.
The jet was originally conceived in the 1990s as a relatively low-cost way to replace the Pentagon’s myriad fleet of ageing fighters with a single common design. The Pentagon hopes to buy 2,443 of the jets to replace everything from A-10 Warthog ground-attack planes, to multirole F-16 and F/A-18 fighters, to the AV-8B Harrier jump jet. There are three versions of the F-35: one version designed for flying from normal land bases, another to fly off aircraft carriers, and another that can land vertically.
But the JSF program has been plagued with repeated delays and numerous technical problems over it is 12 year history. Many of the problems stem from the fact that the Pentagon decided to design, built, test and fly the F-35 all at the same time rather than sequentially like a normal program.
The F-35 was originally intended to be operational with the U.S. Marine Corps by 2010. Now, the Pentagon hopes to have a basic version in the hands of Marine operators by the mid-2015. A fully capable jet won’t be available until 2018.
The original idea to replace different combat aircraft with a single design has resulted in the most expensive defense program in the history of mankind, with the price tag ballooning from $220 billion to about $400 billion.
The Pentagon has effectively bet the future of American airpower on the F-35 though. Despite the astronomical cost, numerous delays, and technical hiccups, the Pentagon has no choice but to continue with the mammoth program: neither the Air Force nor the Marines have a backup if the F-35 program were to die. Only the Navy has the short-term ability to buy additional Boeing F/A-18E/F Super Hornets—which are far cheaper than the F-35 but may not be useful past about 2030.
The Pentagon has effectively bet the future of American airpower on the F-35.
So even though the F-35 continues to suffer glitches in testing—such as cracks being discovered in the airframe or fuel line failures—the program continues with Monday’s incident being just one in a long line of malfunctions.
As for Monday’s incident, sources said the damage to the F-35 was severe and the jet could be a total loss. At the very least, the damage amounts to what the Air Force calls a Class A mishap, which causes more than $2 million in damage. While officials would not comment on the extent of the damage or the cause of the fire, one source suggested that the jet’s integrated power pack could be the cause.
The integrated power pack, which is basically a combination of a 200 horsepower gas turbine, battery, and cooling system, has caused problems in the past—including a 2011 fire.
Congressional sources told The Daily Beast that the fire was in the aircraft’s Pratt & Whitney F135 engine. "The pilot had an engine fire indication on take-off. He safely egressed the aircraft and the fire was extinguished. It is SOP [standard operating procedure] to sequester aircraft for investigation purposes," a Senate aide said.
That is not inconsistent with what sources told The Daily Beast earlier, which could mean that a fire that originated in the Honeywell-built integrated power pack spread to the engine and the rest of the aircraft.
The F135 engine has had several teething problems over the course of its development. Earlier in flight-testing, the engine suffered from vibrations at supersonics speeds in a phenomenon engineers have dubbed a “screech”. Additionally, fan and turbines blades have cracked in testing and on at least one flight test aircraft. But overall development of the F135 has gone relatively smoothly.
If the investigation into the fire were to show that a design or manufacturing flaw in the engine or integrated power pack caused the fire, subcomponents might need to be redesigned and older aircraft may have to be modified to meet to the new standard. However, because the Pentagon is solely responsible for its hardware once the contractor delivers it, the taxpayer is ultimately on the hook to pay for those modifications. That would be the case even if Pratt & Whitney or Honeywell had designed or built flawed hardware.
"We are aware of the incident at Eglin AFB," Pratt & Whitney said in a statement. "We stand ready to assist the Air Force in their investigation."
As a result of the incident, the Air Force has decided to “temporarily suspend” flying its version of the F-35 while it investigates what went wrong. Initially, the Air Force suspended flying only at the unit where the fire occurred, but the service extended the grounding to the all of its F-35s until it is sure the aircraft is safe to fly.
“As a precautionary measure, the Air Force has decided to temporarily suspend all F-35A operations until it is determined that flights can resume safely,” Waggoner said, noting that such practice is common in aviation. “It ensures the safety of our crews and our aircraft so we can determine there is no fleet-wide issue that needs to be addressed."
The F-35 Joint Program Office (JPO), which manages the roughly $400 billion Joint Strike Fighter program for Air Force, Navy and Marines, does not consider the F-35 to be formally grounded however. “No F-35s have been grounded. Air worthiness authorities did not direct a fleet stand down,” said Kyra Hawn, a spokeswoman for the F-35 program office in an emailed statement. “We expect flights to resume in the coming week.”
The fact that the F-35 JPO has not directed the F-35 fleet be formally grounded suggests that the fire might be traceable to a one-off failure rather than a fundamental design defect.
The F-35 JPO could provide no additional information on what caused the F-35 to catch on fire. Nor would they confirm the extent of the damage to the jet. “We will not speculate on cause of the fire while the investigation is underway,” Hawn said.
The U.S. Navy and the U.S. Marine Corps, which also fly their own versions of the F-35, have not suspended their flying operations.
There are currently 104 F-35 in the Pentagon’s arsenal — split between Air Force, Navy and Marine Corps variants, according to Lockheed.