The 787 is the first airplane new applicant that must directly comply with all of the regulations associated, that came out of the changes to [FAR FAA Par 21] 981 and 954. We have worked out way with the FAA in very great detail, every detail in that airplane. Down to every fastener, every bracket, every system, every material, and we probably have more testing on that piece for that regulation than any other part of the airplane. And having been involved in that early on, I tend to think the rule is extra interesting. I am confident that we have done everything we can to understand, engineer and comply with that rule. Now there are some things in that rule that both the FAA and us had to work around, because it was an area, quite honestly, where the FAA got prescriptive in terms of design rather than writing requirements so we worked our way through that. Normally you don't want the airplane to be struck by lightning because it's a maintenance headache. But it's my wish that this airplane gets struck a lot because it will put a lot of people... to go through this at an engineering discussion is at the PHD level. I've been through it and I'm confident. I know the people in the FAA who have worked really hard and have not compromised on the safety on this airplane, specifically in this area of regulation. I don't understand the motive in that, but I'm confident that we have done, and that the people across the table from us have worked their butts off. That was the comment by then-787 chief engineer Mike Delaney on the 787's lightning strike protection system.During a test flight in May, Mike Delaney got his wish. ZA001 was struck by a rare bolt of lightning over Puget Sound, and returned to Boeing Field unscathed. Dreamliner One's lightning strike continues the unbroken streak of Boeing development aircraft enduring lightning strikes in flight testing. Scott Fancher, vice president and general manager of the 787 program walked around ZA001 following its flight that day:
"Post-flight inspections revealed absolutely no damage," said Fancher, who took over the Dreamliner testing program in December 2008. "I walked around the airplane an hour after it landed and you couldn't tell a thing had happened."While the importance of safely flying away from a lightning strike is very validating for the 787 and its more-electric architecture and highly integrated computer systems, the strike itself deserves some additional context.
Electro-magnetic safety of majority-composite aircraft is arguably the most challenging aspect of designing with heavy use of these materials, as a the natural faraday cage protection of a metallic structure is no longer present.
Worth noting, as a standard part of flight test 787s are flown with a special electro-static dissipating fuel additive for additional protection on top of the native protection designed into the systems and structure. While a real-world strike in a testing environment is a crucial milestone, there are important differences from a production aircraft in a commercial environment.
This was also not the first lightning strike of a majority-composite primary structure aircraft. In fall 2009, a production standard Hawker 4000 was struck by lightning near Wichita Mid-Continent Airport in Kansas. The strike happened while the aircraft, RC-7 (N711GD), was on approach and struck the right side of the aircraft near the first officer's seat close to the avionics bay. The aircraft also landed normally with no impact on any of the aircraft systems, requiring only a minor paint touch from the scorch marks on the outer fuselage.
Photo Credit Wings777
Photo Credit Wings777