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F-35 Maintenance Reporting Evolves as Aircraft Matures

 - June 10, 2015, 10:30 AM
Servicemen view a system display of the F-35 Autonomic Logistics Information System. (Photo: Lockheed Martin)

Lockheed Martin has introduced the second of three major software releases it will deliver for the maintenance support system of the F-35 Lightning II fighter. The false reporting codes maintainers experienced using the Autonomic Logistics Information System (ALIS) on earlier blocks of the F-35 should be resolved as the air vehicle matures, the manufacturer said. But the system will be fielded without a radio frequency downlink that would enable the F-35 to send reports while in flight, a feature that has been deferred for later development.

Lockheed Martin (Chalet 316) describes ALIS as the “operations management backbone” of the F-35, an information technology infrastructure that captures and analyzes health and maintenance data for individual airframes as well as for the larger fleet. The system is designed to support F-35 operations, maintenance, fault-prediction and parts deliveries over the lifecycle of the fighter, providing maintainers with timely information over a distributed network.

As of this spring, ALIS Version 2.0, the second of three planned releases, was installed at nine military bases in the continental U.S. and at the F-35 Final Assembly and Check-Out facility Lockheed Martin operates with Alenia Aermacchi at Cameri Air Base in Italy. A version of the system was installed on the amphibious assault ship USS Wasp, where testers validated the system’s performance for F-35 shipboard operations.

“ALIS is progressing per its development plan,” said Jeff Streznetcky, ALIS program director with Lockheed Martin Mission Systems and Training in Orlando. “In terms of major releases, I’d say we’re two-thirds of the way there to getting ALIS fully developed and fielded to our customers.” The third release is planned in 2017 with the conclusion of the F-35 system development and demonstration phase.

Lockheed Martin was testing ALIS version 2.0.1 before releasing it into the field. This version supports a deployable version of ALIS contained in ruggedized transport cases that can be moved on and off aircraft carriers or amphibious ships and deployed to remote operating locations. Before it declares initial operational capability (IOC) of the F-35B short takeoff and landing variant as expected this summer, the U.S. Marine Corps will have verified the functionality of ALIS software as well as the “deployability” of system hardware, Streznetcky said.

An ALIS version 2.0.2 system was in development. This will support the Air Force’s planned IOC declaration for the F-35A in mid-2016. The final release–ALIS 3.X–was in an earlier phase of development, and will support IOC of the F-35C by the U.S. Navy as well as international partner operations.

Health Reporting Codes

The Marine Corps F-35B will begin operations with air vehicle Block 2B software. Fighters that Lockheed Martin delivered to Eglin Air Force Base in Florida, which is home to an integrated training center for F-35 pilots and maintainers, came with earlier versions of the aircraft software, designated Blocks 1B and 2A.

An ALIS predictive, or “prognostic,” health monitoring application that resides with the aircraft software has generated a high percentage of false positive health reporting codes (HRCs) in F-35s with earlier versions of that software. In a report accompanying the Fiscal Year 2016 defense authorization act this spring, the U.S. House Armed Services Committee said that it received “numerous complaints and concerns by F-35 maintenance and operational personnel regarding the limitations, poor performance, poor design and overall unsuitability of the ALIS software in its current form.” Department of Defense (DOD) officials who testified before the committee’s Subcommittee on Tactical Air and Land Forces in mid-April confirmed those reports.

With the health monitoring application, the F-35 generates HRCs that are recorded on a data storage device. The data is later downloaded into the ALIS system, which generates work orders for maintenance actions and administrative tasks for pilots and maintainers to close. Lockheed Martin acknowledged that maintainers at Eglin AFB experienced a high degree of false positive HRCs on F-35s with Block 1B and 2A software–reports that did not require any corrective action. The false reports served to induce unnecessary workload into the system.

The manufacturer described the problem of false-positive reports as a developmental issue that will be resolved as the F-35 air vehicle software matures. Fighters delivered to Luke AFB and Marine Corps Air Station Yuma, F-35 bases in Arizona that were activated after Eglin AFB, came with Block 2B software. Block 2B software “shows a 50 percent diagnostic improvement of false positives” versus the earlier software versions, Lockheed Martin said.

“As the air vehicle system has matured and the software that runs on the air vehicle has matured, the system has been able to fine tune its diagnostic capabilities,” Streznetcky said. “We’ve seen that from Block 1B to Block 2A and from Block 2A to 2B–a continuing reduction in the number of false health reporting codes that have been generated by the aircraft. I’m certain that what is being observed at Eglin is due in part to the fact that the jets they are operating with are of the 1B and 2A variety, and therefore an earlier product that came out of the development lifecycle. We do have objective data that indicates there’s a continual maturation of the prognostics capability on the aircraft.”

The problem should be resolved with later versions of F-35 air vehicle software, Lockheed Martin claimed. “We expect to reach negligible false HRCs with the delivery of Block 3i/3F and new ALIS software currently in development,” the manufacturer said.

One of the more compelling features system designers envisioned for ALIS–an RF downlink that would enable the F-35 to send health monitoring data to the ground while the fighter is airborne–has been deferred for later development in order to better secure the data stream. In the meantime, such data will be extracted from a storage device when the jet lands. While the deferral was “a joint decision” of Lockheed Martin and the DOD’s F-35 Joint Program Office (JPO), Streznetcky referred questions on that issue to the JPO.

Responding to an inquiry from AIN, the JPO issued the following statement: “The Prognostics and Health Management data downlink provides F-35 maintainers with an advanced look into aircraft diagnostics, consumables and weapons status prior to landing. Testing of the downlink revealed the need to upgrade it with enhanced security measures.

“Those improvements will be completed in follow-on development; specific timelines for all Block 4 capabilities are under program review. The downlink has no bearing on the aircraft’s diagnostics performance. The same information can be obtained once the F-35 lands.”