According to a recent story published in Naval News, for the first time, the power module for the F-35C Lightning II multirole combat aircraft has been delivered by a CMV-22B Osprey to an aircraft carrier at sea, the USS Carl Vinson. The engine was an F-135 Power Module which is common to all three variants of the F-35 aircraft. To the casual observer, this may not seem like an event of much importance, but for the Navy and the Marine Corps that fly the plane, this is a very big deal.

It is said that when it comes to the Art of War, amateurs talk about tactics while professionals talk about logistics. And the F-35 coming into naval service created some unique logistical challenges for the Navy and Marine Corps. There are some 500 F-35s currently in service building to a peak strength of over 2,400. While the F-35 holds out the promise of incredible performance and combat capability, none of that will matter if these aircraft cannot be sustained while operating at sea. One of the major problems was that the hot exhaust of the F-35’s engine tended to melt the flight decks of the ships they were landing on. The same problem existed with the V-22 Osprey and its engine nacelles when in the vertical position. The Navy solved that problem by making the decks more heat-resistant. The F-35 also incorporates an automated parts system that tracks every component installed on this enormously complex aircraft to keep track of its performance and durability. This system has also been plagued with data entry problems that are still being worked out.

This is in no way unique to the introduction of a new aircraft into the Navy or Air Force. You can plan very carefully to take all factors into account, but logging hours with the F-35 in the real world is necessary to find problems no one ever thought of. One of those problems for the F-35 was engine swaps. The Lightning II uses the Pratt and Whitney, F-135 Power Module designed to be unplugged and removed from the aircraft. It is then shipped as a single unit to a maintenance facility ashore to be overhauled and then returned to the squadrons as a spare. Building a fleet of F-35s is pricy but their construction cost isn’t the only cost involved.  To keep these planes flying and fighting requires a very long and expensive logistics “tail” of spare parts and engines. This is why about 70 percent of the Navy’s weapons budget is just for the sustainment of the weapons it already has.

When it comes to the F-35C and its modular powerplant, the Navy needed to buy hundreds of spare engines that need to be replaced after a certain number of running hours are logged. The problem was how to get them out to the aircraft carriers that have Lightning squadrons. The F-135 Power Module is a beast in terms of weight and size. It’s over 4,500 lbs and too large to fit into the cargo bay of the ancient C-2A Greyhounds. Further, you cannot just slam the F-35C’s engine onto the deck during a carrier landing and not expect it to be damaged. In contrast, the Osprey will be able to land vertically with a minimum of shock and vibration to the Power Module.