WASHINGTON — Although the Joint Program Office maintains the F-35 program remains on track, the Pentagon's top weapons tester recently raised concerns that the fifth-generation fighter jet's software development could fall behind.

In a Dec. 11 memo, Michael Gilmore, the Defense Department’s director of operational test and evaluation, described as being "not realistic" called the JPO’s current plan to finish work on the F-35’s Block 3F software — the final software block required for full warfighting capability — by July 31, 2017., "not realistic." Rushing the testing schedule and weapons deliveries in order to meet this deadline "constitutes a very high risk of failing" Initial Operational Test and Evaluation — the final phase of testing before a full-rate production decision, Gilmore said.

The JPO recognizes there are about four months of "potential risk" in the 3F testing schedule, but maintains testing will be completed by the summer of 2017, according to spokesman Joe DellaVedova. He stressed that the JPO will not take any "shortcuts" to meet that deadline.

"The JPO does not intend on 'short-cutting' any required test points," DellaVedova wrote in a Jan. 22 email to Defense News. "Removal of test points by the combined JPO, industry and warfighting team occurs only after a thorough and disciplined review of what is required to deliver the promised capabilities."

The goal is to deliver full Block 3F capabilities in the fall of 2017, he said.

As of Jan. 15, Block 3F development flight testing had completed approximately half of all baseline test points, DellaVedova noted.

"Any critical deficiencies identified during the remainder of development flight testing and IOT&E will be coordinated with key stakeholders including the Services and operational test team, to determine the need for any required fixes or other follow-up actions," DellaVedova wrote.

Gilmore's memo, first reported by Aviation Week on Jan. 22, also points to "poor performance" during developmental testing of Block 3i, which is the next planned software release. The Marine Corps declared its F-35B variant operational — called Initial Operational Capability — last summer using Block 2B software; the Air Force plans to declare IOC for its F-35As later this year with Block 3i; and the Navy will declare IOC for the F-35Cs in 2018 with the full 3F software package.

DellaVedova defended Block 3i, saying the software has been continually improved throughout the development test and evaluation process. Early versions of 3i did contain deficiencies, but these issues were addressed and resolved in later increments of the software, he said. The latest version of 3i is being flown with "improved results," he said.

The IOC dates for the Air Force and the Navy are on track, according to DellaVedova.

However, some on Capitol Hill are concerned about potential schedule delays due to software issues, according to a pair of congressional sources.

Until Air Force Secretary Deborah Lee James certifies that the F-35s delivered in fiscal year 2018 will have full combat capability — including "Block 3F hardware, software, and weapons carriage" — Congress will limit procurement funds for the plane, according to the fiscal year 2016 FY-16 National Defense Authorization Act. With the reduced funding, the Air Force can only purchase 34 aircraft, not the 44 in the service’s fiscal 2016 FY-16 budget request, or the extra three F-35As added to this year's appropriationsin the appropriations bill, according to one congressional source.

If the aircraft are not fully combat capable for the fiscal 2018 FY-18 deliveries, it may be too early to begin ramping up production due to future potential retrofit costs, the source said. Right now, the program is preparing for a steep increase in deliveries over the next few years.

Gilmore's memo also raised concern about the Autonomic Logistics Information System, the F-35's integrated maintenance and management system, particularly regarding cyber deficiencies.

"(ALIS) continues to struggle in development with deferred requirements, late and incomplete deliveries, high manpower requirements, multiple deficiencies requiring work-arounds, and a complex architecture with likely (but largely untested) cyber deficiencies," Gilmore wrote.

The JPO has supported more than 2,000 cyber tests of the program, and is committed to ensuring the F-35 will be cyber-secure, DellaVedova said.

"The JPO absolutely agrees with DOT&E that robust cyber vulnerability testing is essential," he wrote. "Our shared objective is to safeguard the F-35 enterprise against the continually evolving cyber threat."

Email: lseligman@defensenews.com

Twitter: @laraseligman

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