We know that the United States Air Force is committed to fielding the conventional runway version of the F-35.
After the start of the Afghanistan war, the head of the USAF stated that he could see a need for the service to split up its F-35 buy between the conventional runway version and the USMC short take-off and vertical landing (STOVL) version.
This idea (which now seems dead) has to be put in context. The goal of the USAF boss was not some STOVL fantasy super-close to the ground troops. It was based on the idea that the USAF could operate out of some shorter runways; knowing the limits of logistics.
This PDF file (click on link it doesn’t right-click, save-as well) is a school study from the USAF war college dated April of 2006. It states that the idea of STOVL for the USAF is a bad one; that even the USMC hasn’t proven the usefulness of STOVL ops with the Harrier and that if one wanted to be truly joint and save money, USAF should buy the U.S. Navy carrier version; the F-35C. It also points out other problems with the F-35B STOVL such as less endurance and range.
The paper is poorly written and full of holes ( I agree with the lack of worth of STOVL). For instance, the author doesn’t really explore the usefulness of the F-35 program. Since the F-35 won’t be able to do anti-access jobs and is too expensive for anything else, the real question is; Does the F-35 provide any value to the USAF? My opinion is, “no”.
In every major conflict involving US ground troops since Operation DESERT STORM, the USMC Harriers have not been unique in their ability to “move forward” and operate “close to the fight”. For example, during DESERT STORM “Hornets based at Shaik Isa utilized the airfield at Jabayl as a FARP [Forward Arming Refueling Point], just as the Harriers did at Tanajib, thus reducing transit time to and from the target area”.
Furthermore, USAF “F16s…generated a tremendous number of sorties while operating from a forward operating location (FOL) at King Khalid Military City (KKMC) in Saudi Arabia, located just 60 miles from the Iraqi border”.
“F-16s operating there were able to exchange their drop-tanks for extra ordnance: KKMC-based missions carried four Mk-84 2,000-pound bombs (double the normal load of two). FOL operations allowed the wing to fly more sorties per day; KKMC missions launched from the…main base in Abu Dhabi to bomb the KTO [Kuwait theater of operations]; landed and rearmed at KKMC for a second sortie to the KTO (which did not require refueling); landed and rearmed at KKMC for a third mission and after attacking the KTO, air refueled to return to Abu Dhabi.”
Like the USMC Harrier, the USAF F-16’s took advantage of a FOL, but the “F-16 carried a larger payload than either the Harrier or the Hornet, and delivered tons of ordnance…with a very small transit and turnaround time”.
Again, nearly ten-years later, during Operation ENDURING FREEDOM (OEF), the USMC Harriers were not alone in their ability to move forward and operate “close to the fight”. In October 2002, a six-airplane detachment of Harriers from Marine Attack Squadron (VMA)-513 set up shop at Bagram, near Kabul, where A-10s had been operating since March of that year.
Later during Operation IRAQI FREEDOM (OIF), Harriers took advantage of a FARP “at An Numaniyah, 60 miles south of Baghdad” but USAF A-10’s also “deployed forward” and operated out of “Tallil Air Base in Iraq”. However, logistics hampered Harrier operations. According to a “Harrier squadron commander…it was a major task keeping such aircraft supplied with jet fuel at that site”. This squadron commander went on to say, “It takes a lot of support and logistics…so we chose to use other platforms”.
Like the Harrier, the F-35B will be a logistics challenge. A number of logistics risks exist with the STOVL variant that do not exist for the other JSF variants, the primary being the vertical lift fan. Although a revolutionary design concept, the reliability and maintainability of the lift fan is still unproven. The lift fan operates on a single shaft that connects to the main engine and spins at a high-rate of speed. According to one study, this lift fan design causes “ added complexity” due to “the need for the clutch to engage and disengage the lift fan”.
Repair of the vertical lift components would very likely call for removing the engine, a traditionally “high repair time task”. Further, the lift fan and swivel nozzle adds to the logistics footprint especially when forward deployed.
According to one study, “While the JSF designers strive to reduce the complexity of the aircraft systems, the fact remains that the STOVL…will by nature be more difficult to maintain than either corresponding CTOL or [Navy] version”. This conclusion centered on “Naval Post Graduate School [studies] which compare projected component designs for the STOVL JSF to current Harrier design and projected [F-35C] design”.