The Army has issued a broad agency announcement for research and development into manned and unmanned drive systems within rotorcraft engines, such as corrosion-resistant gearbox housings, lubrication systems as well as artificial intelligence and machine learning for "drive system prognostics."
The Technology Development Directorate within Army Combat Capabilities Development Command’s Aviation and Missile Center is interested in the “development and demonstration of rotorcraft engine and drive system technologies" as part of the “Supplemental Power, Efficient Engines and Drives (SPEED) program,” the Nov. 5 notice states.
The goals of the R&D effort are to improve component life, power density, reduced life-cycle costs and “loss of lubrication performance improvements” within rotorcraft drive systems, and to improve fuel consumption, power density, sustainability and “surge margin” within rotorcraft engines, according to the notice.
The Army plans to spend $11.4 million on this R&D effort for rotorcraft drive systems and engines between fiscal year 2026 and FY-30, according to the service. The government expects to issue multiple awards each year based on available funds, with each award having a period of performance between 12 and 24 months.
As part of the effort, DEVCOM is seeking technologies “related to topological optimization of additively manufactured corrosion-resistant gearbox housings.” The goals are to reduce weight while “maintaining performance requirements” and to prevent “housing corrosion with a lightweight solution that is not easily damaged,” according to the notice.
The R&D effort will also include research into ways to increase “loss of lubrication emergency operation time” that will allow pilots more time to make decisions on how and where to land.
Rotorcraft gearboxes are required to operate for 30 minutes after a loss of lubrication, according to the Army. And gear coatings can “potentially provide a lightweight solution” to improve loss of lubrication capability. DEVCOM is looking for technologies that improve this capability, “particularly using small, pressurized containers of emergency lubrication material that is expelled upon temperature rise in the gearbox,” the notice states.
AI needed to predict drive system failures
The broad agency announcement notes operation and sustainment costs account for about 70% of the total life-cycle cost of rotorcraft, which can occur when components are removed before they fail.
Army rotorcraft that are part of the service’s Future Vertical Lift portfolio will not initially “have access to past failure data” and won’t be able to develop “condition indicators,” which could lead to “overly conservative inspection intervals” for parts of the drive system. To offset this problem, the Army wants to use AI models to predict drive system failures in FVL aircraft, which could cut down on these conservative inspection intervals.
This part of the R&D effort will involve integrating “physics-based models with actual usage data” to accurately predict failures for these aircraft. The Army anticipates that employing AI models for this type of predictive maintenance could reduce life-cycle cost and increase aircraft availability.
Advanced manufacturing to improve turbine performance
Another aspect of this aviation R&D initiative will be to study ways of incorporating advanced and additive manufacturing processes when making turbine components. The traditional process of manufacturing these parts is through casting, forging and “Computer Numerical Control” machining processes, according to the Army.
The traditional processes “limit the ability to fabricate aerodynamically optimized designs that could improve engine efficiency and enhance cooling capacity,” the notice states. More complex designs could be achieved through additive manufacturing, although the Army’s ability to do this for turboshaft engines has not yet been demonstrated.
Through advanced manufacturing, the Army hopes to reduce fuel consumption due to optimized blade aerodynamics and achieve an improved power-to-weight ratio.
Hybrid VTOL
Separate from the main R&D effort described in the broad agency announcement is an initiative by the Army to solicit “critical data and insights” on hybrid vertical-takeoff-and-landing (VTOL) as well as short takeoff and landing (STOL) concepts.
“The Army is seeking to leverage industry expertise to inform Army decision-making regarding the feasibility, operational impact, cost of adoption and requirements applicable to hybrid technologies for future Army missions,” the notice states.
The Army plans to spend $1.3 million in FY-26 and $1.5 million in FY-27 on this VTOL research effort, with the possibility of making between two and four awards with a period of performance between 12 and 24 months.
The Army is primarily focused on Group 4 and 5 size “unoccupied aircraft” that have a weight of up to 10,000 pounds at takeoff, which have VTOL and STOL capabilities.
Autonomy is a “desirable capability” for these aircraft, but it is not the focus of the S&T effort, the notice states.
The VTOL and STOL research will ultimately inform the Army’s aviation S&T strategy, requirements development and transition planning.
“The scope of this initial Government-funded effort is anticipated to be primarily analytical. However, it may include system integration and testing depending on individual entry points based on maturity of applicant development efforts, industry cost share, or future funding (none currently identified),” the announcement states.
The solicitation will remain open until July 3, 2027.