August 19, 2014: Learning from past mistakes that have spelt trouble for the ALH programme, HAL has decided to go in for a critical design review of the rotor system it has developed for the Light Utility Helicopter prototype. While HAL is moving ahead with the rotor development, the design team has felt it felt necessary to review the rotor system design (critical design review) by an independent agency in order to preclude issues which could come up during the rig tests and flight tests. According to HAL, the rotor design is based on the earlier experience of developing a 5.5 ton class helicopter. The main rotor of the helicopter is a four bladed hinge less type rotor with FEL rotor head with elastomeric bearings (Conical and Radial). The tail rotor is a four bladed bearing less rotor designed to meet all the anti- torque, directional control and manoeuvring requirements. For the review, HAL expects that there will not be major changes in the type of rotor system adopted: hingeless concept for the main rotor, bearingless concept for the tail rotor, number of blades, etc. The design review of the rotor system design needs to primarily cover the safety of design, flying quality characteristics, vibration issues, manufacturing, maintenance, time before overhaul and lifing.