Six US Marine Corps Lockheed Martin F-35B Lightning II aircraft landed on board the USS Wasp amphibious assault ship on 18 May, where they will begin the first phase of shipboard operational testing for the force’s Joint Strike Fighters.

Two weeks of testing – dubbed OT-1 – will now be conducted in the lead up to achieving initial operational capability, acting as the “connecting block” between the testing team, engineers and fleet operations. The equipment, personnel and support used throughout will be similar to those that will be employed in routine operations.

“It’s an interim half-step between fully deployed operations and development tests,” Maj Richard Rusnok, the Marine Operational Test Evaluation Sqn 22 F-35B detachment officer, says.

F-35B landing on USS Wasp - USMC

US Marine Corps

After arriving, the aircraft displayed their short take off and vertical landing capabilities, the USMC says.

Day and night testing using various aircraft configurations will take place during OT-1, as well as day and night weapons loading.

The digital interoperability of the aircraft and ship systems will also be tested throughout the two weeks, along with the F-35B landing signal officer’s launch and recovery software and the logistical and maintenance elements of at-sea deployments.

Modifications had to be made to the Wasp in order for it to accommodate the F-35B, including the installation of the Autonomic Logistics Information System. The Wasp is currently the only vessel in the fleet to have all of the integrated F-35B modifications, Rusnok says.

F-35B landing on USS Wasp - USMC

US Marine Corps

The F-35 will replace three USMC types: the Boeing AV-8B Harrier, Boeing F/A-18 Hornet and the Northrop Grumman EA-6B Prowler.

“We’re looking at the manpower and logistical efficiencies in performing aircraft maintenance and aircraft sustainability over one type/model/series, versus three separate types of legacy aircraft,” says Col Robert Rauenhorst, commanding officer of Marine Operational Test and Evaluation Sqn 22.

The six aircraft involved belong to the Marine Fighter Attack Training Sqn 501 based in Beaufort, South Carolina, and the Marine Fighter Attack Sqn 121 based in Yuma, Arizona.

The USMC has received 33 “B” short take-off, vertical landing model F-35s out of 50 ordered, and one “C” carrier-based model out of two ordered. Requirements are currently 353 for the former and 67 for the latter, Flightglobal’s MiliCAS Fleets database says.