FRIENDCOPTER - Integration of Technologies in Support of a Passenger and Environmentally Friendly Helicopter
Overview
Background & policy context:
Today's helicopters need to be further improved in order to gain more environmental and public acceptance. Helicopters generate external noise, cabin noise and vibrations due to the complex nature of their dynamic systems. They also suffer from NOx emissions, as other transport systems. It was therefore, essential that these issues be addressed in order to improve the situation for the new generation rotorcrafts and to make them environmentally friendly and acceptable to the general public.
Objectives:
FRIENDCOPTER intended to achieve the following main goals:
- Acoustic footprint areas reduced between 30% and 50%, depending on the flight conditions;
- A reduction of up to 6% of fuel consumption for high-speed flight;
- Cabin noise levels below 75 dBA, similar to airliner cabins for normal cruise flight;
- Cabin vibrations below 0,05 g, corresponding to jet smooth ride comfort for the same flight regime.
Due to the large and fast rotating rotor, the non-symmetric rotor flow, the close vicinity of the main gearbox and passenger heads and the specific requests of maximum engine performance, the targets mentioned above were highly challenging, requiring a strong high tech initiative.
Methodology:
The project was structured as follows, into six work packages (WPs):
WP1 - Specifications
The objectives of WP1 were:
- To ensure well defined and harmonised start of the project by confirming and quantifying the project targets and key deliverables envisaged through the main helicopter manufacturers and the engine manufacturer;
- To provide guidelines for an overall integrated research approach on development and operation of environmentally friendly helicopters by specifying the methods to be applied;
- To take precautions against technical imponderabilities by a risk assessment with respect to the methods applied and by identification of potential alternative procedures.
The following methods were used:
- The provision of guidelines for the work planning of the other WPs;
- Rough quantification of the final results expected in the different WPs;
- Specifications of the methods planned including risk assessment.
A specification report defining targets and methods of the programme was issued.
WP2 - Noise abatement flight procedures
WP2 was concerned with the reduction of noise on the ground through operational means (noise abatement procedures) and the prediction of the acoustic impact of such rotorcraft flight operations. Specifically, WP2 aimed to:
- Develop methodologies for the design of operationally viable noise abatement procedures;
- Design and validate the necessary prediction tools to assess the acoustic impact of rotorcraft flight procedures on the ground and assist in the development of low-noise flight procedures.
In terms of noise reduction, the objective was to reduce acoustic footprint areas between 30 % and 50 %, depending on the flight condition.
The tasks within this WP were split into three main topics:
- Identification of the needs and specific objectives relating to noise abatement procedures;
- Development of the models needed to predict the noise emitted by helicopters during various phases of flight and the tools necessary to design low-noise flight procedures;
- Full scale flight tests on different helicopter models in order to provide noise data to the prediction models and assess the low-noise procedures.
WP3 - Engine noise reduction.
The objective of WP3 was to reduce a component of helicopter noise, relevant mainly during take-off and climb, i
Share this page