Boeing cuts 787 wireless system
Unforeseen obstacles prompt Boeing to switch to a wired network for the new jet. One unexpected benefit: It's lighter.
Seattle Times aerospace reporter
Boeing has abandoned its plan to install a wireless inflight-entertainment system on the 787 Dreamliner, one it had touted earlier as saving weight and complexity by eliminating wires.
Boeing will substitute a wired system with cables running to each seat row, instead of a wireless antenna at each row, to feed movies and music to passengers' seats.
Mike Sinnett, director of 787 systems, said the switch will ease the plane's development schedule rather than cause any delay. Paradoxically, he said, the change will reduce weight.
"We're putting in about 50 pounds of wiring and taking out about 200 pounds of other gear" including wireless antennae, wireless access points and thickened ceiling panels, said Sinnett. "And from a schedule point of view, it makes life easier for us."
Boeing made the decision earlier this month because of performance problems with the technology and the lack of bandwidth spectrum in some parts of the world. The switch was first reported Wednesday afternoon on The Wall Street Journal's Web site.
Sinnett said Boeing discovered in December that the wireless chipsets planned for the system didn't perform as expected. In addition, it had difficulty getting regulatory approval around the globe to use the wireless frequencies.
Also, the intended frequencies had to be shared with weather radar in certain parts of the world, reducing the bandwidth available for transmitting movies.
Sinnett said Boeing held onto the wireless system as long as possible, expecting a wired system would add weight. But when the performance issues forced the switch, engineers found the net effect is to reduce weight.
One Boeing engineer who works on the 787 inflight-entertainment systems — and who asked not to be identified as he wasn't authorized to speak publicly — said the decision to switch back to a wired system was not a shock.
"The thinking for a long time has been to keep our options open," the engineer said. "In some ways, it's not that big a deal."
Still, on the heels of a Wall Street analyst's report Monday — hotly denied by Boeing — that the 787 faced likely delays, news of the about-face on the wireless cabin system may prompt more unease in the stock market.
Complex wiring problems caused massive delays and cost overruns on Airbus' A380 superjumbo project.
The issues are not comparable, Sinnett insisted. The 787 Dreamliner will have just 61 miles of wiring, compared with 91 miles on the 767 it will replace and 329 miles of wiring on the double-decker A380.
The 787, Sinnett said, has been designed from the start with a standard systems architecture so that about 85 percent of the wiring is standard on all jets. The 15 percent that varies according to customer specifications is the "simplest element of the system," he said.
The wired system will still preserve the flexibility of the previously wireless passenger cabin, by running wiring under the floor in the seat tracks to each row. The seat-track approach, a departure from traditional wired systems, was developed to bring power cables to each 787 seat.
To change the seating configuration, an airline will not have to change that under-floor wiring but just will plug the seat systems into a different point in the track.
The net impact, Sinnett said, is less technical risk, some weight saved, the system's flexibility and quality preserved plus "a bit of schedule relief."
Dominic Gates: 206-464-2963 or firstname.lastname@example.org