- Unlikely Alliance, Dual Benefits
- Composite Repair Process Enhancements
- Specialised Field Support
- Sesto Elemento Future Development
With eleven 787-8s now in service with All Nippon Airways and Japan Airlines, as the world fleet grows, so too does the propensity for the inevitable occurrences of in-service damage, varying from ramp rash, air bridge impacts as well as MRO-related mishaps and other airport related impacts.
While the missions between car and airplane are different (naturally), the similarities go far beyond the skin, with both Lamborghini and Boeing sharing knowledge and experience with how to deal with a critical decision when accidents happen – to repair or replace composites.
Working with Boeing and the University of Washington’s Advanced Composite Structures Laboratory, Lamborghini developed a “single cell” cage for the Aventador, much in the same way Boeing devised the single piece monolithic barrels for the 787 fuselage. Not only does this save weight, but the strength of the component(s) as well as durability increases significantly.
“We set up a complete strategy in order to determine whether to repair or replace pieces of a car if it becomes damaged. Of course, we made a lot of analyses and identified a few zones that are more critical than others to the safe operation of the car,” said Casper Steenbergen, who heads up Lamborghini’s Advanced Composite Research Center.
“The 787 has been designed from the start with the capability to be repaired in exactly the same manner that airlines would repair an airplane today — with bolted repairs. The ability to perform bolted repairs in composite structure is service-proven on the 777 and offers comparable repair times and skills as employed on metallic airplanes,” says Boeing.
Critical to both support paths for the 787 and the Aventador is the development of specialist non-destructive testing that can be performed virtually anywhere in the world using portable thermography and ultrasound equipment.
“The 787 structure has been designed with adequate strength margin to retain ultimate (certification) load capacity with non-visible damage present and un-repaired for the life of the airplane. If there is an incident where the aircraft has been potentially damaged, the preliminary assessment of the 787 structure would be a visual inspection. Depending on the exact nature of the incident and the findings of a visual inspection, additional damage assessment techniques may be required. This would most likely be a pulse-echo (or other forms of ultrasonic) inspection,” states Boeing.
While Aventador owners will likely have provisions for other automobiles, that is not always the case with airlines, whose schedules can be heavily disrupted through AOG events, as well as incurring significant financial penalties as a result of unplanned downtime and pulling in of other airplanes to compensate for flight changes.
“Airlines have the option to perform bonded composite repairs, which offer improved aerodynamic and aesthetic finish. These repairs are permanent, damage tolerant, and do not require an autoclave. While a typical bonded repair may require 24 or more hours of airplane downtime, Boeing has taken advantage of the properties of composites to develop a new line of maintenance repair capability that requires less than an hour to apply,” adds Boeing.
Bonded repairs have the benefit of not just removing the risk of material corrosion, but also rejoins structures as well as paring out weight-related loads – in effect, it’s as if there had been no damage at all.
It is this sort of co-operation that Boeing and Lamborghini have had to develop in order to make the 787 and Aventador not just serviceable, but also keep intact their residual values in the event any serious structural damage renders either an insurance write-off.
This is part of the reason why Lamborghini was initially reluctant to commit to a production variant of the Sesto Elemento – in part because of the widespread use of carbon fiber but also the cost of repairs given that the suite of technology behind it is both proprietary as well as hideously expensive when it comes to what essentially is a niche product whose costs may never be recouped. Lamborghini is however looking at how it can take lessons from the Aventador and incorporate those into a lower risk Sesto Elemento development, either as a standalone product or as a natural successor to the successful, but now older Gallardo family.
While no one wants an accident, the term itself lends to the fact that damage, however unintentionally caused can have wide-ranging effects. As Boeing increases 787 production and learns from the in-service fleet over the years to come, composite knowledge as well as curable technologies to assist in repairs, as well as development for new airplanes will be invaluable.
The delays to the 787 have been well documented. No question.
What is less talked about is the inherent risks Boeing took to get that airplane where it is today. The 787 has heralded a massive materials leap forward for Boeing – and with the hubbub about composite wings finding their way onto the planned 777-8X and 777-9X family, Boeing’s edge with composite technology is one that will set the marker not just for the aerospace aerostructures industry – but for any industrial field where composites can make an everlasting impact.