Boeing handed over the ceremonial keys of a new 747-8 Intercontinental to Lufthansa Tuesday in what will be the new longest passenger airliner in the skies. The aircraft is the stretched version of the popular 747-400 series Lufthansa currently flies.

The new Boeing jet will enter service at the beginning of June on the Frankfurt to Washington Dulles International Airport route. It features redesigned business and first class cabins that are more luxurious than its predecessor.

"We are excited and thrilled to welcome the 747-8 Intercontinental to our fleet," Lufthansa Chief Executive Carsten Spohr says in a release. "And our passengers will love the new interior, which includes our all-new full-flat business-class cabin."

So far no U.S. airline has placed orders for the stretched and now longest commercial airliner, which measures a little more than 250 feet — more than 18 feet longer than its predecessor.

Until the introduction of this aircraft, Lufthansa lagged behind most of the other major international airlines in offering a business class seat that converts into a fully horizontal bed. At the press of a button, the seat converts into the lie-flat position that measures about 6.5 feet long.

The seats themselves are arranged in a "V" formation allowing for greater shoulder room between seatmates. Other improved features in business class include additional storage space and a much larger, 15-inch individual entertainment screen at each seat.

Unlike the 747-400 where first class was upstairs, that class will be located in the nose of the aircraft on the main deck. The seats in this cabin also convert into fully horizontal beds as shown to the left.

The aircraft seats a total of 362 passengers: eight in first class, 92 in business class and 262 in economy.

Lufthansa ordered 20 of the 747-8, five of which will be delivered this year. As more aircraft come online, they will be deployed on additional routes to Chicago, Los Angeles, New Delhi and Bangalore.