Hindustan Aeronautics (HAL) has conducted noise measurement flight trials for the Dhruv advance light helicopter (AHL).
The testing was conducted in compliance with the International Civil Aviation Organisation (ICAO) to achieve certification from the European Aviation Safety Agency (EASA).
The process involved advanced acoustic programming, and compensation of atmospheric variables against measured noise levels. It was aimed to measure the external aircraft noise levels in three flight conditions, such as take-off, approach and flyover.
HAL CMD T Suvarna Raju said: "The EASA representatives witnessed the entire flight test and preliminary analysis of the recorded noise data, weather parameters and the aircraft parameters shows that the noise levels are within the acceptable limits specified by ICAO for ALH."
The test witnessed eight flights constituting 96 noise runs as part of practise and certification runs.
The hardware, software and technical support for the programme was delivered by Spanish company Anotec Consulting.
Earlier, HAL conducted assessment of test sites at Kolar, Hosur and Mysuru in coordination with EASA and the Spanish firm.
However, EASA finally approved Mysuru airfield as the test site suitable for noise measurement.
The ALH Dhruv helicopter is designed to meet the requirements of both military and civil operators, the company stated.
Currently, the helicopter is being operated by the Indian Air Force, Indian Army, Indian Navy, Coast Guard, BSF and State Governments. The company has also delivered Dhruv to Ecuador, Mauritius and the Maldives.
This all-weather helicopter is a multi-role, multi-mission new generation helicopter in the 5.5t weight class, and is capable of carrying nearly 16 people at heights of up to 10,000ft.
Image: During the test, eight flights constituting of 96 noise runs were carried out as part of practice and certification runs. Photo: courtesy of Hindustan Aeronautics Limited.