曝光臺(tái) 注意防騙 網(wǎng)曝天貓店富美金盛家居專營店坑蒙拐騙欺詐消費(fèi)者

The US Army’s Advanced Composite Airframe Program (ACAP) and the US Air Force funded
DMLCC-BW (Design and Manufacture of Low Cost Composites- Bonded Wing) program have
provided major advances in composites technology for helicopters. Development of syntactic
foams and bonded assembly technology played a major role in increasing composites usages in
helicopters.
Composites played a crucial role in the development of the tilt-rotor V-22 due to its weight
sensitivity. The V-22 uses composite nacelles, wing, fuselage skins, empennage, side body
fairings, and doors as shown in Figure 10. Composites usage in the V-22 is approximately 50
percent of the airframe weight. The DMLCC- BW program provided the bonded assembly
technology used in the V-22. Bonded assembly virtually eliminates mechanical fastening and
allows structural attachments to be integrated into the components. The ACAP program provided
advances in manufacturing technology to reduce costs of the composite components. Automated
fiber placement technology applications to the fuselage resulted in a 53 percent cost savings since
the V-22 aft fuselage skin could be fabricated in one integral piece rather than assembly of 10
skin panels in the original design.
(SM1) 1-10
100%
50%
0%
Carbon
Metal
Fiberglass
Other
Figure 10. V-22 Material Application
The RAH-66 composites applications consist of the tail rotor shroud, main and tail rotor blades,
exhaust doors, lower tail cone, dome and vertical and horizontal stabilizers. The Bell/Agusta
BA609 consists of a third generation composite wing structure and is heavily influenced by the
DMLCC- BW wing program. The BA609 demonstrated low cost and defect free bonded
assembly.
Composite engine air intake ducts with integral heating systems are used on the GKN-Westland
EH101 and Super Lynx 300 helicopters. The inlet duct’s aerodynamic shape is very complex,
transitioning from a rectangular to a ring shaped cross-section and is difficult to fabricate with
metals. Metallic construction requires several parts with joints and multiple fasteners. A
composite duct on the other hand can be manufactured as one-piece, thus saving weight and
assembly costs.
The Eurocopter Tiger has carbon/glass hybrid prepreg engine fairings, glass prepreg blades and a
fuselage, cockpit and tail boom built from Carbon prepreg.
Conclusions
For increased future applications of composites in aircraft structures lowering their costs is
essential. The affordability lesson learned from a survey of US and European aircraft are as
follows:
1. Unitize and integrate multiple parts to reduce fabrication costs in the early stages of the
design process. One such example taken from the US Air Force Composites
Affordability Initiative (CAI) program is shown in Figure 11.
(SM1) 1-11
2. Simplify design and apply automation to reduce variable fabrication costs
• Replace lightly loaded integral stiffeners with Syncore sandwich construction
• Utilize fiber placement, performs, and other innovative material forms to reduce manual
lay-up
• Design for efficient manufacturing processes such as fiber placement and RTM
3. All aspects of the design and manufacturing processes must be addressed to achieve
lower cost composite structures.
• 95% Fewer Metal Components
• 33% Fewer Composite Components
• 96% Reduction in Fasteners
TTooddaayy
DDeessiiggnn FFoorr AAffffoorrddaabbiilliittyy
Reduce Part Count Improve Producibility
Dramatically Reduce Assembly Costs
• Reduce Part Count • Improve Producibility
• Dramatically Reduce Assembly Costs
6363% Figure 11. Unitized Structure for Affordability
References
1. Anon, “ A Brief Look at Composite Materials in Airbus Commercial Aircraft”, High
Performance Composites March/April 1999.
2. Heth, Jenny, “Helicopter Industry Designs for Composites”, High Performance
Composites May/June 2000.
3. Mezzadri, Jean-Claude, “Aerospace Composite Materials are Mature”, SAMPE Europe
Opening Session 1999.
4. Anon, “Materials in the Current Air Force”
(SM1) 1-12
QUESTION/ANSWER FORM
LOW COST COMPOSITE STRUCTURES
Name of Author Ravi Deo
Paper Number 1
Name of Discusser Samy Amin, Pratt & Whitney, Canada
Question: Any plans to look at composite applications in gas turbine
engines?
Answer: Not that I am aware of at this time.
ONCE THIS FORM HAS BEEN DULY COMPLETED PLEASE RETURN TO THE
AVT PANEL ASSISTANT – THANK YOU
Original equipment
manufacturers (OEMs) have
several lines of
communication with airlines’
　
中國航空網(wǎng) m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：航空資料35(120)