The F-35 is projected to carry a larger variety of weapons as more software, bomb racks, and testing to validate these are developed—but we will not know until 2021 which of those weapons are actually combat suitable. Moreover, in order to carry something other than two large guided bombs it will have to use external weapons and racks, significantly reducing the plane’s already disappointing range and maneuverability—and, of course, more or less eliminating stealth.
The ability to penetrate heavily defended airspace to destroy fixed targets deep in enemy territory is an often-cited justification for the F-35. Of course, the F-35’s limited range—less than legacy F-16s—means that it is unlikely to be able to perform what the Air Force likes to call “deep strikes” well inside the homeland of large nations such as Russia and China.
The 2016 DOT&E report describes some official foot-dragging that has delayed putting the F-35’s penetrating ability to the test. For instance, the program is only now starting to receive the critical ground radar simulator equipment, which mimic enemy radar systems, that are needed to conduct robust testing of the F-35’s effectiveness in highly contested, near-peer, scenarios. It’s only receiving that equipment because it was sought and procured by DOT&E when it became clear that the Services and the JSF Program Office were not going to pursue a test infrastructure adequate for replicating the near-peer threats the F-35 is expected to be able to counter. Deliveries of this equipment have begun but will not complete until early 2018. The JPO has not planned or budgeted for developmental flight-testing against it.
The military does developmental and operational testing of stealth aircraft at the Western Test Range at Nellis Air Force Base in Nevada. The tests are conducted against the ground radar simulator equipment and surface-to-air missile (SAM) launchers. Aircraft being tested fly over these arrays to see if the aircraft’s onboard sensors—in particular its electronic warfare systems and ground mapping radar—combined with offboard intelligence provided via data links can detect the threats and respond appropriately, such as by warning the pilots, jamming the signals, or firing defense suppression missiles.
The problem is a complicated one because the radar signals that reveal the presence of a SAM, for instance, thereby allowing the aircraft to either target the SAM or avoid it, are not necessarily distinctive and often closely resemble the signals of radars that pose no immediate threat to the aircraft. The F-35 can't carry enough weapons to bomb everything. Its sensor and sensor fusion system must be able to tell the difference between enemy SAM radars that pose a genuine threat and the many innocuous radars that may be within range of detection—general purpose air surveillance radars, short-range, low-altitude air defense radars targeting weapons and not aircraft, and even nearby civilian air traffic control and weather radar systems.
Equally crippling, until the ground radar simulator equipment is in place, the F-35 program will be unable to properly develop, validate, and update the F-35’s mission-critical onboard software files, called Mission Data Loads (MDLs). MDLs are huge files specifying all target and threat locations together with their individual electronic and/or infrared signatures and all relevant mapping data. Without accurate, up-to-date MDLs, the F-35 cannot find targets or evade and counter threats—nor can it carry out the networking and sensor fusion functions that are said to be its primary strengths. The F-35 cannot go to war without its MDLs. The MDLs also need to be updated continuously with information concerning such things as threats, targets, and signals that is gathered on every F-35 mission. F-35 pilots can only be sure the MDLs they need to survive work properly after they have been tested over ranges equipped with the necessary ground radar simulator equipment.
New and complete MDLs must be created for each theater or conflict zone by a central reprogramming lab using massive data inputs from the relevant combat command. F-35s operating out of England would have different files from F-35s based in Japan, for example. Only one such reprogramming lab exists today and, due to JPO mismanagement, it is has only recently been scheduled to receive necessary upgrades to produce a validated MDL. It takes the lab 15 months to produce a complete MDL. If F-35s are suddenly needed in a new, unanticipated theater of operation, those F-35s will not be able to fly combat missions for at least 15 months.
Because the full range of necessary ground radar simulator equipment for the reprogramming lab is not yet in place, DOT&E stated that the earliest the reprogramming lab will be able to produce validated MDLs just for IOT&E will be June 2018. That is nearly a year after the planned IOT&E start in August 2017—and two years after the Marines declared the F-35B initially operationally capable. DOT&E further stated that F-35 MDLs suitable for combat “will not be tested and optimized to ensure the F-35 will be capable of detecting, locating, and identifying modern fielded threats until 2020.”
Ineffective as a Close Air Support Platform
The F-35 has plenty of shortfalls performing air-to-ground interdiction missions well away from the immediate battlefield, but it is even worse in its other intended air-to-ground role directly in support of engaged troops, close air support (CAS). DOT&E concluded that the F-35 in its current configuration “does not yet demonstrate CAS capabilities equivalent to those of fourth generation aircraft.” This statement is particularly disturbing in light of the Air Force chief’s recent statements that the service intends to renew its efforts to cancel the CAS-combat-proven A-10 in 2021.
CAS is the other major mission where a lack of an effective cannon will significantly limit the F-35’s combat usefulness.
An effective cannon is essential for many CAS missions where any size bomb, guided or unguided, would pose a danger to friendly troops on the ground or where there are concerns about collateral damage, such as in urban environments. The cannon is even more crucial when our troops are being ambushed or overrun by enemies only meters away, in “danger close” situations where only pinpoint effects delivered by the most highly accurate fire can help our side and kill or disperse the enemy. Ground commanders interviewed as part of a recent RAND study said they preferred the A-10’s cannon fire even to guided munitions because 80 percent of the cannon rounds fired hit within a 20-ft radius of the aiming point, providing exactly the kind of precision that danger close situations absolutely require. Cannons are also most useful for hitting moving targets because a cannon burst can lead the target in anticipation of movement.
None of the three F-35 models in the current fleet can use cannons in combat. In fact, none of them are even close to completing their developmental flight tests—much less their operational suitability tests—for airframe safety, accuracy, and target lethality. Even worse, based on preliminary test experience, it appears that the severe inaccuracy of the helmet-mounted gunsight on all three F-35 versions that makes the cannon ineffective in air-to-air combat will also make it ineffective in CAS—and that the helmet’s accuracy problem may be technically inherent and incurable. Note that the cannon accuracy requirements for CAS are considerably more stringent than for air combat: when shooting in close proximity to friendly troops, even minor accuracy problems can have tragic consequences. As mentioned before, the gun pods for the Marines’ F-35B and the Navy’s F-35C will likely add another source of inaccuracy—also possibly incurable—and remain untested for CAS. The combat suitability of F-35 cannons for CAS will not be known until the end of Block 3F IOT&E, which is unlikely before 2021. Failure to complete these CAS tests realistically—a distinct possibility given JPO mismanagement and delaying of test resources—will certainly jeopardize the lives of American troops.
In addition to the critical cannon inaccuracy problem, the error-inducing chaos of symbol-clutter in the pilot’s helmet display is particularly dangerous in the CAS role. DOT&E says the current system is “operationally unusable and potentially unsafe to complete the planned testing due to a combination of symbol clutter obscuring the target, difficulty reading key information, and pipper [aimpoint] stability.” Even when the symbols being displayed by the helmet do not obscure the pilot’s ability to see the target, the F-35’s canopy might. The jet’s canopy is a thick acrylic material with a low observable coating to preserve stealth. This makes the canopy less transparent and according to the DOT&E appears to be distorting the pilot’s view.
Further limiting the cannon’s effectiveness in each version of the F-35 is the number of 25 mm rounds it carries—182 for the F-35A and 220 for the B and C. This is grossly deficient for CAS, especially when compared to the over 1,100 30 mm shells carried by the A-10. While the A-10 has enough cannon rounds for between 10 and 20 attack passes, any variant of the F-35 will only have enough for two, maybe four, passes.
Even more limiting in the effective use of any CAS weapon, cannon or other, is the F-35’s inability to fly low and slow enough to find typical hard-to-see CAS targets and safely identify them as enemy or friendly, even when cued by ground or air observers. Due to its small, overloaded wings, the F-35 cannot maneuver adequately at the slow speeds that searching for concealed and camouflaged targets requires—and being completely unarmored and highly flammable, it would suffer catastrophic losses from just the small rifle and light machinegun hits inevitable at the low altitudes and slow speeds required. In sharp contrast, the A-10 was specifically designed for excellent low and slow maneuverability and, by design, has unprecedented survivability against those guns, and even against shoulder-fired missiles.