Considering the history of multi-service fighter programs, the F-111 comes to mind, but there is also the JPATS, JSTARS and the Osprey tilt-rotor, it should surprise no one that Rand Corp’s analysis of the such programs shows that there are no savings. In fact, it shows that developing aircraft variants separately is less expensively than a common aircraft with service-specific variants.

The theoretical savings are a mirage:

A Rand Corp. report produced to guide future U.S. Air Force program plans has concluded that the F-35 Joint Strike Fighter program will cost more than three single-service programs would have done. That conclusion drew a sharp riposte from Lockheed Martin, which accused the report’s authors of using “outdated data” that overstated the F-35’s projected operating costs by a factor of two.

Lockheed Martin based its criticism on numbers that cannot be found in the report. The company declined to give a source for those numbers, stating that they were “government data.” The Joint Strike Fighter program office distanced itself from the argument, saying it had “no real issues” with the report, and did not confirm any of the company’s figures.

Rand’s Project Air Force team produced the report, which was requested in 2012 by then-commander of Air Force Materiel Command Gen. Donald Hoffman, as it became clear the JSF would be running many years behind the schedule that was planned up to 2010.

The study was based on historic data up to November 2011, including the fiscal year 2010 selected acquisition report (SAR). Rand, a think tank founded by the Air Force and still closely associated with the service, did not use the fiscal year 2011 SAR (issued in March 2012) which disclosed a three-year slip in development and actually reported higher cost projections than the 2010 report.

Because the JSF program is incomplete, and because no other joint fighter program has been completed as planned, the researchers used data from a variety of programs—from the F/A-18E/F and F-22 fighters to the T-6A turboprop trainer and E-8C surveillance platform—to gauge the historical cost increases in joint and single-service programs.

They did not focus on absolute costs, but on the percentage growth of estimated costs between the launch of a full-scale development program (Milestone B; MS B) and points five and nine years after MS B, the latter corresponding to the most recent JSF data available in late 2011.

………

Researchers compared the actual growth of F-35 estimates at the nine-year mark with growth rates for three separate programs based on historic growth with the F-22, the most comparable single-service fighter program. The same adjustments were applied to O&S costs, although a later and higher estimate of F-22 operational costs (at 14 years after MS B) was also included.

The study’s conclusion: The JSF estimated life-cycle cost (LCC) in 2010 was already higher than that of three single-service programs. “Under none of the plausible conditions that we analyzed did JSF have a lower LCC than the notional single-service programs.” The report does not recommend any changes to the JSF program, but advises the Air Force to avoid joint projects in future.

Of course, this does not answer why this is so.

One could argue that it is typically ambitious of joint programs, since the military’s goal of getting more bang for the buck is almost always more bang, not less buck, but if that were the case, the JPATS, the T-6 Texan II, where an extant turboprop trainer was adapted to a tri-service primary trainer would not have had a greater cost growth than the T-45 Goshawk, a naval advanced trainer, where an advanced jet was fully navalized to to land on carriers, but it did have a greater percentage cost growth.

When you further add the specifics of the JSF, specifically the Marine Corps requirement for STOVL, which f%$#s up the other variants in some very profound ways.