A British Airways Boeing 787-8 (G-ZBJG) was struck by lightning shortly after departure from London Heathrow on July 22nd en route to Chennai in India. The flight, BA35, continued on the 9 hour flight to India, but upon landing it was discovered that the aircraft had 42 to 46 holes in the fuselage from lightning strike damage. This was an unusual level of damage to a 787 and the worst outcome to date from a lightning strike to that aircraft type.
While the flight completed the trip safely, British Airways decided to return the aircraft to London on July 29th without passengers to undergo maintenance. A day later, the aircraft was returned to service, a week after the incident.
With metal aircraft, electricity can easily be conducted across the skin to a wing-tip or other edge from which lightning can easily be dissipated. Composite aircraft are built with metal foil, woven wire, or most commonly an expanded metal mesh to dissipate the impact of lightning strikes. The two aircraft with more than 50% composite material, the 787 and A350, utilize different approaches to lightning strike protection for their composite fuselages.
This incident, which caused a one week loss of revenue on a 787-8, indicates that while passengers remained safe, the aircraft required specialized maintenance that apparently could not be performed locally once the aircraft landed, necessitating an expensive ferry flight back to its home base.
Repairing damage to metal aircraft is fairly straightforward, as a “scab patch” is placed over a damaged area and riveted in. Composite aircraft require a more complex repair process that requires removing the damaged composites from affected areas, replacing them with new material that includes new lightning strike protection, and heating that area to cure and chemically bond the new material to the existing composites. This incident shows just how expensive that process can be on the Boeing 787.
.” A day later, the aircraft was returned to service, a week after the incident.” This statement is rather ambiguous though it is partially alluded to in the heading. “A day later” in relation to what ?
The aircraft was said to have returned to operations a day after repairs.
The aircraft returned to service one day after it arrived back in London for maintenance.
But the net result was a week without revenue, as apparently action to return it to service
could not be performed in Chennai.
http://newsite.airinsightresearch.com/boeing-787-grounded-week-lightning-strike/
The linked article does NOT claim that BA performed a repair, just that the airframe was inspected by personnel at Heathrow. The elapsed time from departure from LHR on July 22 to the return to service (presumably on July 30) appears to be due to uncertainty about whether the “42 to 46 holes” were misreported:
“British Airways has confirmed that the lightning strike occurred, but says that it “does not recognise the description of the damage”
Your assertion that “This incident shows just how expensive that process can be on the Boeing 787,” apparently in contrast to repairs of a metal fuselage, is not supported in any way by that article. That BA chose to consume those non-revenue days at Chennai and then to absorb the cost of a ferry flight to LHR for further inspection may be entirely due to lack of experience/expertise of BA personnel.
The article includes:
“An individual jet liner is struck about once every two years, on average, and aeroplanes are designed accordingly,” he says. “Once in a while there’s exterior damage – a superficial entry or exit wound – or minor injury to the plane’s electrical systems, but a strike typically leaves little or no evidence. You might not even notice it.”