Lycoming LTC1K-4K
The Lycoming LTC1K-4K was the T53-derived free-turbine engine adapted for the Bell XV-15 tiltrotor. Modifications allowed vertical starting and operation as each wingtip nacelle rotated between helicopter and airplane modes. Two engines drove the proprotors through nacelle transmissions and an interconnecting shaft. NASA’s history gives 1,250 shaft horsepower for normal continuous operation and 1,550 shaft horsepower for takeoff, with the characteristics table limiting the takeoff rating to ten minutes. Those engine ratings are distinct from the lower power imposed by the XV-15’s helicopter-mode transmission torque limit.
Identity
- Aliases
- LTC1K-4KLTC1K4K
- Domains
- aviation
- Identity Level
- model
- Kind
- turboshaft
- Name
- Lycoming LTC1K-4K
- Status
- unknown
Details
- Description
- The Lycoming LTC1K-4K was the T53-derived free-turbine engine adapted for the Bell XV-15 tiltrotor. Modifications allowed vertical starting and operation as each wingtip nacelle rotated between helicopter and airplane modes. Two engines drove the proprotors through nacelle transmissions and an interconnecting shaft. NASA’s history gives 1,250 shaft horsepower for normal continuous operation and 1,550 shaft horsepower for takeoff, with the characteristics table limiting the takeoff rating to ten minutes. Those engine ratings are distinct from the lower power imposed by the XV-15’s helicopter-mode transmission torque limit.
- Family
- Lineage
- Note
- Modified T53-L-13B adapted for starting and operation throughout the XV-15 tilting-nacelle range.
- Related Propulsion System
- Relationship
- direct-derivative-of
- Sources
- Accessed Date
- 2026-10-29
- Note
- Engine development section and Appendix A document T53-L-13B modifications for vertical starting/running and the LTC1K-4K designation; continuous and takeoff ratings are distinct.
- Published Date
- 2000
- Publisher
- NASA
- Title
- The History of the XV-15 Tilt Rotor Research Aircraft: From Concept to Flight
Links
Assets & Meta
- Creation Time
- October 29, 2026 at 15:25:22 UTC
- Updated Time
- October 29, 2026 at 15:25:22 UTC
Other
- Sources
- Accessed Date
- 2026-10-29
- Note
- Engine development section and Appendix A document T53-L-13B modifications for vertical starting/running and the LTC1K-4K designation; continuous and takeoff ratings are distinct.
- Published Date
- 2000
- Publisher
- NASA
- Title
- The History of the XV-15 Tilt Rotor Research Aircraft: From Concept to Flight