The incident involving Ethiopian Airline’s Boeing 787 Dreamliner igniting at London’s Heathrow Airport on Friday will present a public test of Boeing’s carbon technology.
Although preliminary investigation has suggested the aircraft’s lithium-ion batteries were probably not the cause of the fire, the incident has raised additional questions about the safety and reparability of the aircraft that Boeing had hoped would put the company ahead of its competitors.
"Everyone in the industry is going to follow this closely," said Hans Weber, president of TECOP International and an aviation consultant who has worked on composite testing technology. "It's the ultimate test."
In the quest for cutting operating and fuel costs, Boeing’s engineers turned to carbon composite materials that had been previously used in aerospace while also introducing some major innovations such as carbon-plastic composites and a weight-saving electrical system. The latter includes the troubled lithium-ion batteries, which caught fire on two 787s in January.
According to Weber, the burnt plane of Ethiopian Airlines will serve as a public testbed, revealing whether composite-built planes could be repaired promptly and at reasonable cost, as such extensive repairs have not yet been performed on a commercially operated carbon-based aircraft.
Unlike Airbus, which opted for composite panels bolted to a framework similar to conventional aluminum panels for its A350, Boeing created one-piece barrel-shaped fuselage sections. Though Boeing’s solution is said to offer better aerodynamics, it is more difficult to repair or replace.
The 787's composite skin can be patched by grinding out the damaged section, applying fresh layers of fibre and resin and then curing with heat under vacuum pressure, according to a Boeing engineer.
The work can be done on site, and repair stations have been learning to make repairs to service the plane around the world. However, questions remain regarding the complexity and cost of the repairs.
Boeing could make a new piece of fuselage and attach it if the damaged area was not too large, said the Boeing engineer. In the worst case, the entire rear section of the fuselage could be replaced, which, according to Weber, might cost more than the plane is worth.
The fire aboard Ethiopian Airlines Boeing 787 Dreamliner was spotted on Friday afternoon while the plane was parked at a remote stand. No passengers were onboard.
Britain's Air Accident Investigations Branch called the 787 fire a "serious incident" and said the initial investigation was likely to take several days.
Fires break out on parked planes about 60 times a year, and most are from human error such as leaving a circuit on or a discarded cigarette butt. A fire on a different type of plane might have gone unreported.