Advanced Composite materials

1. Advanced Composite materials Used in construction on new technology aircraft and considerations in their use Péter Marosszéky FRAeS MIFA MAOPA (USA) Adjunct Senior Lecturer & Research Fellow University of New South Wales School of Aviation Faculty of Science New Technology composites

2. Introduction • The areas that need to be considered: • Occupational Health and Safety • Advanced composites • Damage tolerance and assessment • Repair Assessments • Repair schemes & processes • Specialized equipment & tooling • Approved MRO’s • Training New Technology composites

3. Health & Safety Hazards • Risks & hazards can be controlled • Use of MSDS data • A wide range of safety procedures have been developed and approved • Current FAR 145.163 and EASA Advisory Circular 65-33 requirements • High overheads & retraining • Manufacturer programs ie: Boeing’s “Gold Care” program New Technology composites

4. Advanced Composites • A range of advanced composites in use on new generation aircraft • Two primary advanced composites are in use on the Boeing 787 and the Airbus A350XB • Boeinghave opted for the Torayca 3900-series highly toughened carbon fibre-reinforced epoxy prepreg – unidirectional tape (various widths) & narrow slit tape (for fibre replacement) and woven fabric forms Majority of the 3900 – series made from intermediate modulus T800S fibre. New Technology composites

5. Advanced Composites • Boeingcontinued: • The surface finishing provides resistance against moisture and contaminant ingress: Cytec SurfaceMaster 905. • A high-temperature bisaleimide composite material, that allows application & removal of paint without compromising the integrity of the sub-structure New Technology composites

6. Boeing 787 series New Technology composites

7. Boeing 787 continued • Other primary structures • Window frames & Engine Nacelles use Hexcel HexMC trademarked as HexPly AS4 carbon fibre prepreg (350°C/177°F cure) 8552 epoxy prepreg resin (Nordam) • Wing & Trailing edge components use Hexcel’s HexFlow RTM6 with Cytec Surface Master 905 • Some landing gear components utilize Hexcel IM-7 fibre. New Technology composites

8. Airbus A380 series • Primary structure: • Empennage – Carbon fibre reinforced plastic (CFRP) • Fin leading edge – Glass fibre reinforced plastic (GFRP) • Radome – Quartz fibre reinforced plastic (QRFP) • Upper sections of fuselage – Glass reinforced Aluminium Laminate (GLARE) New Technology composites

9. Airbus A380 series New Technology composites

10. Airbus A350XB series • Airbus have selected the Hexcel HEXPLY M-21E Carbon fibre toughened epoxy prepreg composite for primary structures New Technology composites

11. Damage tolerance & assessment • Advanced composites have Significant weight, stiffness and strength advantages over Aluminium • Advanced composites are susceptible to damage with greater resistance than Aluminium • Advanced composites are susceptible to sunlight (infra-red) exposure, however pre-spun prepreg carbon fibre is less affected due to the tight weave reducing surface area of resins/catalysts New Technology composites

12. Damage tolerance & assessment continued… • Boeing and Airbus tests have been validated by the ASTM • Advanced Carbon fibre in use on the 787 and A350 has been certified to allow continued airworthiness if impact contact does not leave a visible sign, no further action need be taken • If damage is visible then action must be taken in accordance with the respective SRM (Structural Repair Manual) New Technology composites

13. Damage tolerance & assessment continued… • An example of the effects of damage and subsequent fatigue propagation, tests have shown that in tight weave carbon fibre a breach of the structure not exceeding 2.54cm/1.0in. Will not propagate any further • Larger areas of damage repaired and processed in accordance with manufacturer specifications will have permanent repair status. New Technology composites

14. Damage tolerance & assessment continued… • Airbus research and assessment (validated by (ASTM) has shown the damage tolerance of GLARE is significantly better than Aluminium, however not as resistant Carbon fibre prepreg New Technology composites

15. Damage tolerance & assessment continued • Electrical and Fluid exposure damage. • Electrical: • Advanced Carbon composites are electrical conductors • Copper mesh is embedded in the structure to provide for conductivity and earth return for electrical systems as the “earth return” New Technology composites

16. Damage tolerance & assessment continued… • Fluid exposure: • Coatings applied during manufacture provide protection against phosphate ester fluid (Hydraulic fluids) ingress • Water and waste protection against ingress • Corrosion is prevented by the use of Titanium fasteners New Technology composites

17. General & specific applications New Technology composites

18. Repair assessments • Considerations of damage assessment • Area of damage • Location • Structural requirements • Type of material • Equipment and materials available at location New Technology composites

19. Repair assessments continued… • Repair must be in accordance with manufacturers SRM • Must consider: • Proximity to major structural elements • Aerodynamic cleanliness especially for RVSM and RNP factors • Repair permanency New Technology composites

20. Inspection products • Portable FTIR4100 Fourier Transform Infra-Red (FTIR) spectroscopy to measure the effect of heat damage caused by lightning strikes, fire and engine exhaust • Olympus NDT35RDC hand held device check for possible impact damage include sub-surface damage • BondMaster1000e multi-mode test device to check for disbonding & delaminations. • OmniScan MX and Epoch 1000i using two similar ultrasonic phased array device to detect cracks, delaminations and inclusions New Technology composites

21. Repair Schemes & processes • Most repairs envisaged for in-service will be conducted in-situ, manufacturers have designed specific repair schemes for the range of materials & structures • MRO’s are developing processes for repair & maintenance of advanced composites eg; Lufthansa Technik AG has developed a method for the semi-automated repair of fibre composites, process uses scanning to within 1/100th of a millimetre using optical measurement techniques & computer controlled milling machine to create the bonded surface & perfectly matched pre-cuts of individual composite layers. New Technology composites

22. Specialized equipment & tooling • Some of these include: • The HEATCON HCS9200B Dual zone hot bonder • The HEATCON HCS9000B Single zone hot bonder • The HEATCON HCS2046-02 Phosphoric Acid Containment System (PACS) • A range of Composite Cutting Tools (CCT) for accurate and damage free machining & shaping New Technology composites

23. Approved organizations • Currently most MRO’s and airline MRO’s are gearing up for regulator & manufacturer accreditation • OEM’s also provide after market services for operators that do not have access to approved organizations. New Technology composites

24. Training • There are a number of training organizations that provide Advanced Composite training in addition to OEM’s. This type of training is referred to as Advanced Skills training, requiring on-going refresher training to retain qualifications and proficiency. • A Part 145 organization must receive training from a Part 147 training organization. New Technology composites

25. Questions • Thank you New Technology composites