The Army issued a cure-notice to Lockheed on 10 April 1969, citing 11 technical problems, and unsatisfactory progress on the program. The main issues were the half-P hop vibration issue, and the aircraft gross weight exceeding program requirements. In response, Lockheed proposed an "improved flight control system" (ICS) to reduce rotor oscillations, and steps for removing excess weight and addressing other minor issues in production helicopters. The Army felt Lockheed's solutions to the cure-notice issues would delay the program and increase costs. Citing Lockheed's inability to meet the production timeline, the Army canceled the AH-56 production contract on 19 May 1969, but retained the development contract in hopes that the issues could be resolved.