The Air Force’s New Gunships Shake, Rattle and Roll
Vibration problems threaten to delay the AC-130J
The U.S. Air Force’s newest AC-130J Ghostrider gunships will enter service later than expected because of plans to load extra weapons on the four-engine planes. But the Pentagon’s top weapons tester is even more worried that other nagging problems could hold up the aircraft.
In 2014, crews had trouble picking out targets because the two prototypes were shaking so much in the air, according to the latest annual report from the Director of Operational Test and Evaluation.
On top of that, one of the aircraft had a mid-air accident that completely shut down test flights. “Several problems require resolution and will affect the subsequent development test schedule,” the report explains.
For one, the AC-130J apparently vibrates much more than the previous AC-130W Stinger II aircraft. Crews had serious trouble focusing powerful sensors and pointing laser designators at targets.
In a fight, this could mean the difference between shooting an enemy or hitting friendly troops nearby. The AC-130 is a modified C-130 transport plane armed with huge side-mounted gun turrets.
The report doesn’t explain why the new aircraft shake so much. However, the Ghostriders have more powerful engines than any of the previous AC-130s. The four Rolls-Royce turboprops with their special six-bladed propellers could easily jerk sensitive equipment around quite a bit.
In addition, the video cameras and weapons on the J-models are designed to be easily removed and replaced. The mounts for these systems might not stay in place as well as the more permanent hardware on older variants.
If that wasn’t bad enough, electrical interference—like putting your wireless router too close to the microwave—caused problems for new hand-held controls. When the crew uses the remotes, the Ghostrider’s various turrets often start and stop moving without warning, the report notes.
“The program has reported some progress in the laboratory environment
on both issues, but definitive solutions have not yet been
demonstrated on the aircraft,” the Pentagon evaluators say in their overview.
Far more worrisome, one of the AC-130Js experienced a “temporary departure from controlled flight” on a test mission, according to the report.
While the report added few details, the pilots apparently had to fly the gunship faster than recommended—putting equally ill-advised strain on the airframe—to escape a more serious accident.
After the February 2014 incident, the Air Force promptly stopped flying the prototypes for an undisclosed amount of time. The service launched an investigation and issued new rules to the test crews on how to handle the gunships.
As a result of all these issues, the Ghostriders have completed less than a third of the planned test flights. As of January, both prototypes had been in the air for fewer than 100 hours in total.
In the end, the Ghostriders will be four months late for their first assessment of how they might fare on real-life missions. The Pentagon doesn’t expect a more comprehensive initial operations test and evaluation—needed before full production can begin—until October.
Have gun, won’t travel
Unfortunately, that timeline could drag out even more if the Air Force can’t get its third prototype AC-130J ready for the experiments.
The flying branch plans to install a 105-millimeter howitzer on this prototype. Until recently, this massive cannon was a standard weapon on all of the AC-130 models. But the flying branch expected the next generation of gunships to rely on precision-guided munitions such as Hellfire and Griffin missiles and GBU-39 Small Diameter Bombs.
In November 2012, AC-130Ws dropped the GPS-guided SDBs on targets in Afghanistan for the first time ever, according an official briefing. Marine Corps KC-130J Harvest Hawk gunships have already fired Hellfires and Griffins in combat, too.
But the huge gun is significantly cheaper than any of these guided weapons. And the shells contain far less explosives, making them better suited to densely populated areas full of civilians.
“An AC-130 … precisely delivers very low yield munitions with a 30 and a 105 [millimeter cannons] … and they’re very inexpensive to deliver,” Lt. Gen. Bradley Heithold, the commander of the Air Force Special Operations Command, told Breaking Defense.
So three years ago, the Air Force started looking at ways to mount the devastating weapon onto the Stinger IIs and Ghostriders. With the new armament fitted, the Ghostrider’s crew would expand from seven to nine. The weight of the gun, ammunition and other gear could also change how the planes handle in flight.
But the program—nicknamed Dragon Fire—has not produced a suitable arrangement yet, according to the report.
If the flying branch can’t provide the third prototype for tests, Pentagon weapon testers recommend adding an extra crew member to the cannon-less AC-130Js. This addition would help make the evaluation more “operationally relevant,” according to the annual review.
The aerial commandos also expect a “directed energy weapon”—like a deadly laser or millimeter-wave beam—to replace the howitzer in the future, Heithold said. The Air Force has toyed around with this idea for a decade.
In 2007, Boeing announced it installed a turret-mounted laser in the belly of an old DC-130H—originally used to launch Ryan Firebee target drones—for further study. Two years later, Air Force crews successfully fired the weapon and reportedly destroyed a target on the ground.
But there’s been little to no news about this so-called “Advanced Tactical Laser,” and it’s unclear if the project was really a success. Four years ago, the Pentagon canceled development of a similar, larger system fitted to a heavily-modified Boeing 747 airliner.
Regardless, the Pentagon report doesn’t mention beam weapons of any sort as part of the current test plan.
The Air Force is also still looking at whether the new Ghostriders can actually survive in a real fight. In their 2014 assessment, the evaluators voiced serious concerns about the aircraft’s apparent lack of armor.
At the same time, commanders in the field are still demanding the gunships. Most recently, AC-130s have been among the many planes attacking Islamic State militants in Iraq.
The flying branch already plans to “buy back” two of the older AC-130U Spooky IIs in the next budget request—which have the valuable howitzer—to help avoid any shortfalls, Heithold said.
The Air Force originally planned to get rid of the older gunships in the next few years. But the General insisted that the problems with the Ghostriders shouldn’t be seen as “delays.”
“I wouldn’t call it a delay,” Heithold explained. The plan is to “field the J-model correctly.”
With all of these hurdles, American commandos and other troops on the ground can only hope the Air Force will have the Ghostriders ready for action sooner rather than later—without the excessive shaking.