Pratt & Whitney is designing a new class of jet engines optimized for Collaborative Combat Aircraft (CCA) and advanced cruise missiles. This initiative reflects a broader shift in U.S. Air Force priorities toward cost-effective, high-performance propulsion systems for unmanned platforms operating in contested environments. The development aligns with emerging requirements under the Air Force’s Next Generation Adaptive Propulsion (NGAP) and Adaptive Engine Transition Program (AETP), while also carving out a niche below those flagship efforts.
New Engine Class Targets Sub-AETP Applications
The new engine family is intended to fill a gap between traditional expendable missile engines and the high-end adaptive-cycle engines developed under AETP. According to Jennifer Latka, Vice President of Pratt & Whitney’s F135 program, this engine class will be “smaller than AETP” but still leverage lessons learned from adaptive propulsion research. It is designed to power platforms that are more affordable than manned fighters but more capable than current-generation drones or cruise missiles.
While full specifications remain undisclosed due to classification and competitive sensitivities, the engine is reportedly being tailored for long-range missions with high subsonic or low supersonic speeds—ideal for CCA drones operating alongside manned aircraft like the F-35 or B-21 Raider. The same propulsion core could be adapted for advanced cruise missiles requiring greater range and survivability in contested airspace.
Strategic Fit Within USAF’s CCA Vision
The U.S. Air Force’s CCA program aims to field multiple classes of autonomous collaborative aircraft that can operate as force multipliers alongside manned platforms. These drones are expected to perform roles such as ISR (intelligence, surveillance, reconnaissance), electronic warfare (EW), decoy operations, strike missions, and even air-to-air combat.
The propulsion system plays a critical role in enabling these missions by balancing range, speed, thermal signature management, and affordability. Unlike legacy drone engines derived from commercial turbofans or turbojets like the Williams F107 used in Tomahawk cruise missiles or Honeywell TF33 variants found in legacy ISR aircraft—the new engine class will be purpose-built with modularity and stealth considerations from inception.
Modular Design Philosophy Informed by AETP
The design approach draws heavily from technologies matured under AETP—particularly variable-cycle capabilities that allow the engine to optimize performance across different flight regimes. However, unlike the GE XA100 or Pratt XA101 demonstrators intended for sixth-generation fighters under NGAD (Next Generation Air Dominance), this new engine will likely omit some complexity to reduce cost and weight.
Instead of full three-stream adaptive cycles seen in AETP prototypes—which allow switching between high-thrust combat mode and fuel-efficient loiter mode—the CCA/cruise missile engine may use simplified variable geometry components or fixed-cycle designs with enhanced thermal management systems. Such trade-offs aim to deliver 70–80% of adaptive benefits at significantly lower cost per unit.
Dual-Use Potential Across Munitions and UAVs
This propulsion family could serve as a common core across multiple mission sets:
- Collaborative Combat Aircraft: Medium-sized UAVs operating semi-autonomously with manned fighters; requires high endurance and moderate thrust-to-weight ratios.
- Cruise Missiles: Long-range standoff weapons needing compact form factors with efficient fuel burn at subsonic speeds; potentially replacing legacy AGM-86B/C/D engines.
- Attritable Platforms: Low-cost strike drones designed for swarming or saturation tactics; benefit from simplified yet reliable jet propulsion.
This dual-use potential mirrors trends seen in other domains—for example Northrop Grumman’s efforts on common avionics cores across loitering munitions—or Lockheed Martin’s push toward open architecture across its UAV portfolio.
Competitive Landscape: GE vs Pratt vs Others
This development positions Pratt & Whitney against General Electric—which has also hinted at similar efforts outside NGAD/AETP—and potentially smaller firms like Kratos or Aerojet Rocketdyne exploring expendable turbine solutions. GE’s XA100 remains ahead in TRL within the adaptive space but may be too large/complex for expendable or semi-expendable applications like CCAs or cruise missiles.
Boeing’s MQ-28 Ghost Bat (developed with Australia) uses a commercial-derived turbofan; however future iterations may adopt purpose-built powerplants if U.S.-aligned CCAs require deeper integration into joint strike packages involving radar cross-section constraints or long-duration loitering over denied territory.
Toward Flight Testing: Timeline Still Unclear
No flight test dates have been announced publicly. However, given recent USAF budget allocations—including $392 million requested in FY25 for CCA development—it is likely that prototype testing could begin within 24–36 months if funding continues apace. Latka confirmed that “hardware is already running,” suggesting ground testing has commenced on early demonstrators.
If successful, this propulsion line could enter low-rate production before the end of the decade—timed with initial operational capability targets set by USAF for its first tranche of CCAs around 2028–2030.
Implications for Future Strike Architecture
The emergence of this new engine class underscores how propulsion innovation remains central to distributed airpower concepts championed by USAF leadership under initiatives like Agile Combat Employment (ACE). Smaller but capable engines enable wider dispersal of assets without relying on vulnerable forward bases—a key requirement when facing peer adversaries like China across vast Indo-Pacific distances.
If adopted widely across CCAs and next-gen cruise missiles alike, Pratt’s new engine line could become a cornerstone component underpinning future U.S. airpower projection strategies—offering both flexibility in platform design and resilience through quantity over exquisite complexity alone.
