Boeing South Carolina has not yet revealed when its first 787 Dreamliner will take flight for the first time, much less when it will be delivered to Air India this summer.

But this much is certain: It won’t be the first Boeing airplane to be delivered from North Charleston, or even the first one delivered recently.

That’s because two 737s, the airframer’s best-selling single-aisle jets, were handed over to Turkish Airlines at Charleston International Airport in December, a Boeing spokeswoman confirmed.

Special circumstances led to the previously unreported Lowcountry deliveries.

The planes — Next-Generation 737-900ERs— were assembled in Renton, Wash., said Linda Lee, the spokeswoman, but then they had to been flown to Delaware where a Boeing subcontractor installed auxiliary fuel tanks.

Since the Delaware airport’s runway wasn’t long enough to accommodate a fully fueled take-off, Lee said, the planes had to make one more trip before flying home to Eurasia.

Turkish Airlines could not be reached for comment Monday. It picked Charleston, where the planes were officially delivered not by Boeing but by an aircraft servicing company.

“We just accommodate what the airline customer requests,” Lee said Monday.

Delivering from South Carolina is a good deal for Boeing and its buyers, too, thanks to the state’s tax code.

The list price of a 737-900ER is $89.6 million, according to Boeing’s website. Yet the S.C. sales tax for any maximum tax item, like aircraft, is just $300.

That same cap will also apply when Boeing South Carolina begins delivering its 787-8 Dreamliners — listed at $193.5 million — later this year.

But before any plane can be delivered, it must undergo flight tests.

On April 27, minutes before the first locally assembled Dreamliner rolled out of the factory, Boeing Commercial Airplanes CEO Jim Albaugh said it would take its first flight in three weeks.

He reiterated that prediction last Tuesday during his remarks at Boeing’s annual investor conference in St. Louis, saying “there’s a good possibility that airplane could fly toward the end of this week.”

But as of Monday, Boeing South Carolina did not have a firm date about the inaugural local flight.

Meanwhile, the situation is at least as uncertain at Air India, where a pilot strike is in its third week.

Hundreds of pilots are protesting wages and a plan to train their colleagues from the former Indian Airlines in how to fly the 27 Dreamliners on order.

Air India has been losing money since merging with Indian Airlines in 2007, and the strike has led to canceled flights, accusations and recriminations, and further financial problems for the airline.

Still, industry experts say the recently approved multibillion-dollar government bailout of the national carrier means the labor strife isn’t likely to affect the imminent deliveries from North Charleston and Everett, Wash.