Guy Norris Los Angeles

The tension is mounting for Boeing and its 787 operators as the company prepares to hand over certification data to the FAA from exhaustive tests of the redesigned lithium-ion battery system.

The timing of Boeing's recovery plan from the 787 grounding—now entering its 10th week—and the resumption of commercial services in particular, all hinges on FAA approval of these certification tests. Boeing, which fast-tracked the certification process by conducting around-the-clock ground tests in its extensive Seattle laboratory complex, hopes it will be wrapping up the final reports this week. Testing is also scheduled to include flights of the revised battery system on one aircraft, provisionally set for March 23-24, and ground evaluation in another.

Yet the under-the-gun manufacturer and its customers could see 787s back in the air sooner than most industry observers expect. Assuming the FAA agrees the redesign complies with the special conditions set out in its January airworthiness directive, airline sources say Boeing could be granted approval to resume production flight tests as early as the end of this month. The move would help clear the logjam of completed aircraft building up at Everett, Wash., and Charleston, S.C., and mark a major step toward resuming normal operations.

The aircraft, including some that were undergoing work at a paint facility in Fort Worth when the grounding occurred, will only fly if they have been modified with the battery enclosure and venting system. Airline sources say the batteries on each aircraft also must be either original “901” units that have passed Boeing's new inspection system or be of the updated design agreed on with lithium-ion battery manufacturer GS Yuasa.

In addition, a number of other aircraft stranded at airports around the world are also expected to be cleared for one-off ferry flights to modification centers by the end of the month. Aircraft thought to be cleared for these flights, which will be permitted without the need for the battery enclosure, include LOT Polish Airlines' 787s in Chicago and Warsaw and a United Airlines 787 in Los Angeles; all will be ferried to United's maintenance facility in Houston. Several Qatar Airways aircraft are also expected to make ferry flights to Doha International Airport by March 31, including one airplane stored at London Heathrow Airport and four others at various sites around Qatar. In addition to the battery tests and checks required by the FAA for a one-off ferry flight approved in February, the batteries in each aircraft will be required to pass Boeing's new inspection procedure before flying.

However, despite these encouraging signs for operators, it could still take approximately two more months before services resume. Even assuming swift FAA approval, airlines indicate the earliest commercial flight could resume is not until late May. All Nippon Airways (ANA), the launch airline for the 787 and—with 17 of the type in its fleet—the carrier that has been impacted the most by the grounding, believes that even when regulators agree that the redesign meets the revised special conditions applied to certification, the retrofit kit will take approximately a month to be installed in its aircraft. Similar holdups face those awaiting delivery of new aircraft. Norwegian Air, which was due in April to accept the first of three 787s scheduled for 2013, has leased two Airbus A340s—one for two months and the other for three—to provide capacity in the interim.