Transonic speeds, just below the sound barrier, are the most critical spot of the flight envelope for a fighter plane. These are the speeds where, historically, the majority of aerial combat takes place. And it is at these speeds where the F-35 needs to be the most nimble to be an effective fighter.
The program has attempted to fix the maneuverability performance problems by making changes to the F-35’s flight software rather than by redesigning the actual flight surfaces that are the cause of the problems. The software, called control laws, translates the pilot’s stick commands into behavior by the aircraft. One would expect that certain force by the pilot on the stick would result in an equivalent response by the plane. Because of the software changes, that’s sometimes not the case. For example, if a pilot makes a sharp stick move to turn the plane, the control law software now results in a gentler turn to prevent problems such as (and including) dig-in. F-35 apologists try to dismiss such issues by claiming that the F-35 was never intended for close-in aerial dogfighting, a claim belied by the Air Force’s insistence that the jet be equipped with a short range air-to-air gun.
As an air-to-air fighter, the F-35’s combat capability is extremely limited because at the moment the software version only enables it to employ two missiles, and they have to be the radar-guided advanced medium-range air-to-air missiles (AMRAAMs); in the future it will carry no more than four if it wants to retain its stealth characteristic. The F-35’s capability as an air-to-air fighter is currently further limited because the AMRAAM is not optimized for close, visual-range combat. (Eventually, upgraded software versions will allow the plane to carry missiles other than AMRAAMs, but not any time soon.) This means that any fight the F-35 gets into had better be short, because it will very quickly run out of ammunition.
Its gun would be available in close-in fighting as well, but it’s not currently working because the software needed to effectively use it in combat hasn’t been completed. The cannon in the F-35A sits behind a small door on the side of the aircraft that opens quickly an instant before the cannon is fired—a characteristic intended to keep the aircraft stealthy. Test flights have shown that this door catches the air flowing across the surface of the aircraft, pulling the F-35’s nose off the aimpoint resulting in errors “ that exceed accuracy specifications .” Engineers are working on yet more changes to the F-35’s control laws to correct for the door-induced error. Making these changes and performing the subsequent “regression” re-testing to confirm the effectiveness of the changes have delayed the actual gun accuracy tests. Until these tests occur, no one can know whether the F-35A’s cannon can actually hit a target.
The F-35B and F-35C will both use an externally mounted gun pod rather than an internal version like the Air Force model. Because of differences in the shape of the fuselage of the two models, the Marine Corps and Navy will use different model gun pods. Both have been test-fired on the ground, but the flight tests to see what effect the pods have on the jet’s aerodynamics are only just now beginning. DOT&E has warned that, as happened with the gun door on the F-35A, unexpected flight control problems are likely to be discovered. The fixes to these will have to be devised and then tested as well. Only then will the program be able to begin the fuller in-flight accuracy testing, which is necessary to determine whether the gun pod is accurate.
Developmental testing delays, and the process of fixing the problems that testing will likely uncover, are severe enough that the program may not have an effective gun for Initial Operational Test & Evaluation. This could not only further delay scheduled testing but also, more importantly, prevent the aircraft from reaching the warfighter any time soon.
Infective as an Interdiction Bomber:
There are several major reasons F-35s will have extremely limited interdiction usefulness—the Air Force’s and Marine Corps’ declaration of “initial operational capability” notwithstanding.
For instance, defense companies in Europe, Russia, China, and even Iran have been hard at work for years developing and producing systems to defeat stealth aircraft. And they have had some success. We saw this clearly in 1999, when a Serbian missile unit shot down an F-117 stealth fighter with an obsolete Soviet-era SA-3 surface-to-air missile (SAM), a system first fielded in 1961. Serbian air defense crews discovered they could detect the stealth aircraft by using their missile battery’s longwave search radar. Then, using spotters and the missiles’ own guidance radars, the Serbian forces were able to track, target, and kill one stealthy F-117. To show that was no fluke, the Serbian SAMs hit and damaged another F-117 so badly it never flew in the Kosovo Air War again.