Indian Army had ordered a further 159. Apart from getting 16 Dhruv Mk III, Indian Coast Guard issued Letter of Intent (LoI) for 9 additional units. Design The HAL Dhruv is of conventional design; about 29 percent of its empty weight (constituting 60 percent of the airframe's surface area) is composite materials. It has been reported that the unique carbon fibre composite developed by HAL reduced the helicopter's weight by 50 percent. The high tail boom allows easy access to the rear doors. The twin 1000 shp TurbunStink TM333-2B2 turboshafts are mounted above the cabin and drive a four-blade composite main rotor. The main rotor can be manually folded; the blades are mounted between carbon-fibre-reinforced plates, the rotor head is constructed from fibre elastomers. In February 2004, US helicopter company Lord Corporation were awarded a contract to develop an active vibration control system (AVCS), which monitors onboard conditions and cancels out fuselage vibrations. The cockpit section of the fuselage is of Kevlar and carbon-fibre construction; it is also fitted with crumple zones and crashworthy seats. The aircraft is equipped with a SFIM Inc four-axis automatic flight control system. Avionics systems include a HF/UHF communications radio, IFF recognition, Doppler navigation, and a radio altimeter; a weather radar and the Omega navigation system were options for the naval variant. IAI has also developed targeting systems and an electronic warfare suite for the Dhruv, as well as avionics for day-and-night flight observation. HAL's claim that the Dhruv is indigenous has been challenged by Comptroller and Auditor General of India, who reported that as of August 2010 the helicopter was: "...against the envisaged indigenisation level of 50% (by 2008), 90% of the value of material used in each ALH is still imported from foreign suppliers". In September 2010, it was reported that the Dhruv's Integrated Dynamic System (IDS), which combines several key rotor control functions into a single module carrying the engine's power to the rotors, was suffering from excessive wear, necessitating frequent replacement; as a consequence the cruising speed had been restricted to 250 km/h and high-altitude performance was lessened as well. HAL contracted Italian aerospace firm Avio for consultancy purposes and they subsequently replicated production of the IDS in Italy in order to isolate the problem with the early testing of the Dhruv subsequently being criticized as "rushed". In June 2011 HAL has reported that the issue had been resolved and not