Program slashes maintenance time for the B-2 fleet

  • Published
  • By René Boston
  • Air Force Research Laboratory Space Vehicles Directorate Public Affairs
A critical material scale-up problem that directly affected the operational maintainability of the Air Force’s B-2 Spirit fleet has been solved, thanks to engineers from the Materials and Manufacturing Directorate, working with the B-2 Systems Group and material processing experts.

Through this effort, Alternate High Frequency Material, or AHFM, configured aircraft have shown much lower maintenance manhours per flight hour and have maintained a fly rate more than double the rest of the fleet.

“To date, four AHFM B-2 bombers have been delivered to the Air Force,” said Doug Carter, program manager. “The rest of the fleet will be modified with AHFM progressively as they undergo periodic depot maintenance.”

To improve the B-2 fleet mission capability rate, a major effort was initiated by the B-2 System Group to remove tape covering access panel gaps and fasteners and replace it with AHFM. This material exposes the gaps and fasteners for easy removal and replacement of access panels, without any material restoration required. Successful flight tests demonstrated the effectiveness of the AHFM design, but upon material scale-up for fleet-wide implementation, consistent batch-to-batch performance could not be obtained.

Consequently, the fleet-wide AHFM implementation was postponed due to the high risk associated with the material performance. With the threat of cancellation, experts from the Manufacturing Technology Division initiated a $2.8 million AHFM Rapid Response Process Improvement, or RRPI, program within weeks to solve the B-2 System Group’s primary maintainability problem. This team rapidly identified AHFM manufacturing problems and implemented solutions.

The successful program gave the B-2 Systems Group and Air Combat Command the confidence to implement AHFM fleet-wide, both increasing mission capability rate and decreasing maintenance manhours per flight-hour by 50 percent. The program resulted in a significant increase in aircraft availability and cost savings.

“In fact,” added Mr. Carter, “AHFM is projected boost the (mission capability) rate by 15 percent, which is equivalent to providing the Air Force with an additional six to seven B-2 aircraft.”

In addition, the AHFM RRPI program developed and validated a repeatable manufacturing process that enabled material transition to the B-2 fleet. Key factors that were inhibiting consistent batch-to-batch production were identified . AHFM was re-implemented within six months of the RRPI initiation. The B-2 Systems Group was able to proceed with fleet-wide implementation.

Production of AHFM-like materials had previously been done in modest quantities by small specialty material manufacturers. Throughout this program, the Manufacturing Technology team demonstrated the capability to manufacture material in large quantities (500-gallon batches) that consistently meet tight performance specifications. This has enabled the manufacturer to reliably deliver material on-time and on-budget, reducing aircraft downtime.

"This program is just one example of how the Manufacturing Technology program routinely helps the Air Force field advanced capability while simultaneously reducing cost and cycle time,” said John Mistretta, chief of the Manufacturing Technology Division.

The AHFM RRPI program enhanced the fleet’s high-priority maintainability program and improved material delivery schedule and production cost. The program reduced the material production schedule from 26 weeks to 12 weeks and implemented an improved test method that saves eight days per batch.

Maintenance actions previously requiring a week of aircraft downtime for repair now require as little as 30 minutes. The results of this program have caught the attention of other weapon system program offices.

“Lessons learned from this program are being applied to the production of new weapon systems, thereby saving the Air Force additional dollars,” Mr. Carter said.