Helicopters are widely used in the field of general aviation due to their excellent low altitude performance. As a key capability for helicopter flight performance, near ground maneuvering flight is an important subject in helicopter flight testing. In order to ensure the safety and controllability of helicopters during ground maneuvering flight tests, real-time monitoring of some key parameters during helicopter flight is necessary. In response to the testing requirements for close range measurement of rotor tail rotor and real-time monitoring and alarm of aircraft near ground height during helicopter flight tests, key technologies such as matrix laser ranging technology and platform control algorithms were studied to determine the design plan for key testing technologies for helicopter near ground flight. Based on this, a helicopter near ground flight safety monitoring and alarm system was developed to achieve high-precision measurement within a hundred meters of ground height during helicopter maneuvering test flights, with accuracy and time delay meeting the requirements of flight test. This has important reference significance for the design of future helicopter flight test systems.