Are composites safe? Speculation is dangerous, and conspiracy theory worse. Yet the fact remains we have witnessed another composite fibre incident in the Air Transat Airbus rudder event (Flight International, 15-21 March). Maintenance rather than design may prove to be the cause, yet the apparent acceptance of composite constructions, known unknowns, by the aviation industry, has major implications for any aircraft builder. Even if we ignore the role of rudder detachment from the fin in the AA587 story, composite design and construction remains an issue. The industry knows about badly "cured" composites as new build structures, but what does it know about the effects of time, temperature, and fatigue on key resin states, peel effects, and the very fibre of such components during their life? And what of substituting fibre for metal without designing-in load paths as subchassis structures that can carry stress and damage? Ultrasound may help, but our tools for monitoring composites are few. Composite analysis using electrical potential and acoustic laser techniques for structural integrity checks exist, but are old composites subject to them? Do we now have a new phenomenon to consider – the ageing composite airframe? Has time already told? Lance Cole Swindon, Wiltshire,UK
No liability for BA flight Whatever the view taken by the US Federal Aviation Administration, UK Civil Aviation Authority and other safety experts, the impression that British Airways could have been faced with a compensation bill of £100,000 ($193,000) if it had cancelled its long-range three-engine Boeing 747 flight (Flight International, 8-14 March) is wrong. The new European law on compensation is bad, and the European Regions Airline Association (ERA) continues to condemn it. One of its major failings is its complete lack of clarity which has led to much misreporting of the new passenger rights. What is clear is that an airline is not required to pay compensation if a flight is cancelled because of extraordinary circumstances beyond its control. These include "unexpected flight safety shortcomings" – surely an engine failure at take-off fits this description. Because the law is unclear, ERA has tried to reduce confusion by publishing a guide for air travellers on www.eraa.org. A dispute between passengers and airline staff would be the last straw in circumstances such as the BA flight. Andrew Clarke Director Air Transport Policy ERA, Woking, Surrey, UK
Sound Balance The European Express Association (EEA) may welcome Directive 2002/30/EC ("Cargo carriers applaud Europe's new noise rules" – Flight International, 25-31 January), but the balanced approach does not address the challenge of noise from growth in day and night operations at many European Union airports. The balanced approach was a device for the International Civil Aviation Organsiation to buy time. The prime safeguard, tougher ICAO Chapter 4 noise standards, is a chimera. Most of today's aircraft already perform better than tomorrow's standard – there is little pressure on industry (airlines and manufacturers) there. Scope for operational measures to reduce noise impact is limited and safety must remain paramount in defining operational practice and controlling pilot workload. And then there are land-use measures, hardly something an individual airport can address and over which the European Commission has no obvious competence. Development has long since taken place around many airports that have been established on the edge of major conurbations for 50 years and more, and they are located there precisely because that was the market for which they were built, and for which they continue to serve. The directive addresses operating restrictions as a line of last resort in the balanced approach, and nothing else. Growing operations at night, when ambient noise levels are lower, will be a key battleground for testing the efficacy of this policy. Martin Wright Sutton, Surrey, UK
Three always beat one Surely flying on three engines for about 9h is safer than flying for 3h on one engine? I am curious to know how P Eves (Flight International, 8-14 March) makes the assertion "It surprises me that the BA captain and the airline operator did not consider Murphy's Law." What makes your correspondent think that the crew and company did not take all factors into account before making an informed and evaluated decision to continue with the flight? Matters such as these are a question of informed risk assessment. It is surely the aircraft commander who is in the best position to make such judgements. Aviation still represents one of the safest methods of travelling even when there is an engine out. Robert Taylor Nottingham, UK
Source: Flight International
