A fire on an empty Boeing 787 Dreamliner on Friday forced London’s busy Heathrow Airport to temporarily close both its runways and attracted more unwelcome attention to the high-tech but problem-prone jet.

The cause of the blaze on the Ethiopian Airlines plane has not been determined.

But based on the location of the damage — in a section of the plane made in North Charleston — analysts said it doesn’t seem to be a recurrence of the battery problem that grounded all 787s for more than three months this year.

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Early theories ranged from human errors like something left in the plane or left on in the galley to airplane malfunction, such as a wiring fault.

“Until we even know where the fire started, you just can’t say,” Scott Hamilton of Issaquah, Wash.-based aviation consulting firm Leeham Co.

There were no passengers aboard the plane at the time of the afternoon incident, according to the London airport.

Television images showed firetrucks and fire-retardant foam around the jet, which was parked on a remote stand. They also showed serious damage to the top of the jet’s rear fuselage near its green, yellow and red tailfin.

The fire, wherever it started, breached the crown of the composite fuselage, leaving a hole and raising questions about how or if that can be repaired.

Mary Schiavo, a former inspector general for the U.S. Department of Transportation, said American and British investigators will be interested in the fire’s effect on the plane’s skin.

The National Transportation Safety Board said it was sending an “accredited representative” to Heathrow to assist in the investigation.

“Here they’re going to want to know how hot it was, and if it was so hot that you would expect anything to burn and melt, or if it wasn’t, what the implications of composites are,” said Schiavo, now an attorney at Motley Rice in Mount Pleasant.

According to several reports, the plane was sitting on the tarmac for eight hours before smoke was detected.

Asked what she thinks the most likely cause was, Schiavo said wiring.

“Because it was powered and if it had ground power it shouldn’t have been drawing much power from the battery unless it was a situation where it was overcharging,” she said.

Boeing released a statement on Twitter shortly after the incident was reported.

“We’re aware of the 787 event @HeathrowAirport and have Boeing personnel there,” the statement said. “We’re working to fully understand and address this.”

The plane in question, which bore the name “Queen of Sheba” and registration ET-AOP on its side, was one of four 787s Boeing has delivered to the African airline through last month, all from its 787 factory complex in Everett, Wash. According to reports, the plane was the first 787 to resume flights after the Federal Aviation Administration lifted its grounding order in April.

While this 787 did not undergo final assembly or delivery at the North Charleston Boeing complex, like all 787s, its aft-fuselage section was made here and its mid-body was assembled here.

The incident is likely to put pressure back on the Chicago-based aerospace giant, which seemed to be moving past the troubles it had with the 787’s lithium-ion battery in the first half of the year.

In those incidents, one on the ground in Boston and one in the air over Japan, the damage was to the bottom side of the jet, toward the middle and front of the fuselage.

Before the grounding, Boeing had delivered 50 787s, and was ramping up to make up for the years of delay before it delivered its first 787 in September 2011. Boeing is now making about seven 787s per month, with 1.5 per month coming out of North Charleston and the rest out of Everett.

Boeing shares, which had reached a 52-week high of 108.15 Friday, plunged down as much as 7 percent following news of the fire. The stock rebounded somewhat to closed down 4.7 percent at $101.87.

The British airport had reopened its runways by 6 p.m. BST – 1 p.m. EST – the airport reported on Twitter.

Meanwhile, a Thomson Airways 787 traveling from England to Florida on Friday had to turn back after experiencing a technical issue.

The British airline said that its from Manchester Airport to Sanford, Florida had returned to Manchester “as a precautionary measure.” Thomson said all passengers had disembarked from that plane and engineers are inspecting the aircraft.

Reach Brendan Kearney at 937-5906 and follow him on Twitter at @kearney_brendan. The Associated Press contributed to this report.

Ethiopian Dreams back in the air next week

BBC News – Boeing 787 Dreamliner returns to service in Ethiopia flight