A two-year-old, previously undisclosed partnership between Epic Aircraft parent Aircraft Investor Resources (AIR) and Farnborough Aircraft Corp. Ltd. (FACL) has ended in legal action. The companies had been cooperating in the joint development of their respective Epic LT and Kestrel JP100 (formerly Farnborough F1) turboprop-single designs. UK-based FACL is suing AIR of Las Vegas for up to $100 million in damages, alleging that AIR has failed to deliver the F1 prototypes that FACL paid it to build and that AIR has sought to extract additional payments from FACL by threatening to destroy the first prototype aircraft. AIR has countersued, claiming that the F1/Kestrel JP100 illegally incorporates Epic design features and components.