Boeing's stock plummeted more than 4.5% in only a few hours on 12 July as safety concerns about the 787 were revived by an onboard fire that appeared to severely damage the composite structure of an empty Ethiopian Airlines Dreamliner parked at London Heathrow.
The incident that shut down the world's busiest airport temporarily is now the subject of an investigation by the UK's Air Accidents Investigation Branch, with Boeing, the US National Transportation Safety Board and the Federal Aviation Administration also dispatching representatives to assist.
Ethiopian released a statement saying the aircraft had been parked at the airport for more than 8h and was empty when the fire was finally noticed.
Video of the external structure revealed the most significant damage in the crown of the aft fuselage where the leading edge of the tail attaches to the airframe. That area stretches above the last few rows of the passenger cabin, the rear lavatories and the rear galley section.
Although the worst visible damage to the Ethiopian 787 seems far removed from the underbelly electronics bays, the scene showing airport fire crews dousing the jet with foam retardant quickly revived memories of the incidents involving overheating batteries in January that led to a four-month worldwide grounding.
But 787 flights are continuing as scheduled, despite an unknown technical issue that forced a Thomson Airways 787 to return to Manchester after take-off as a precautionary measure.
Other carriers publicly professed confidence in the twinjet. United Airlines assured worried travellers on Twitter it was operating the 787 as scheduled, and LAN Airlines filed a flight plan for an inaugural service to Lima, Peru from Los Angeles using the Dreamliner.
At the same time, the fire raised fresh jitters about the twinjet despite Boeing's claims it has experienced fewer glitches overall with the Dreamliner's introduction than the airframer saw 18 years ago on the 777.
The incident appears to mark the second confirmed fire onboard that spread to the cabin. The first such incident took place in 2010, while the 787 was still in flight test. The investigation revealed the fire was the result of an assembly error on a component in the electrical system.
The British Air Line Pilots Association (BALPA) released a statement late on 12 July suggesting the incident could shake the confidence of 787 flight crews if the cause is not identified.
"Pilots and crew need to have utmost confidence in the aircraft and all parties in the industry need a full and transparent explanation as to what has been identified as the root causes in this series of events," BALPA says.
The status of the damaged aircraft, registered as ET-AOP, remains unknown as this article went to press. The extensive fire damage shown in the fuselage crown appears to exceed Boeing's public descriptions of repair capabilities for the 787's composite structure.
Given the extent of the damage, investigators will likely also check the fire tolerance of the resins used in the 787's carbonfibre reinforced plastic-based fuselage.