Developing C-17A Control Laws In-Flight
Abstract
The C-17A was known for Level 2 handling qualities during aerial-refueling and extensive turbofan time delay during both aerial-refueling and powered-lift configuration landing. This increased the pilot compensation required for aerial-refueling and decreased safety margins for adverse wind condition landings. The Aerial-Refueling Handling Qualities Improvement (ARHQI) was a three-axis control law designed to improve HQ with a vertical-speed feedback loop. Additionally, ARHQI implemented flap and spoiler bias with elevator feedback to create a throttle-controlled drag differential, with zero net pitching moment, to augment relative fore-aft control and reduce time delay. Robust Flight Path Control was a control law designed to reduce time delay by mixing flap, spoiler, and elevator with throttle movement to increase powered-lift control. These two control laws were developed in a risk-reduction program including control law first-flight, safety build-up, in-flight control law tuning, offset landings, tanker contacts, and lessons learned for future flight control developmental testing.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2018
- Accession Number
- AD1061320
Entities
People
- Daniel Edelstein
- Duncan Reed
- Patrick Ris
Organizations
- Air Force Test Center