Wright J65

However a series of delays due to design changes by Curtiss-Wright, such as substituting the Sapphire's machined midsection solid forged diffuser frame with a fabricated one of welded nodular iron,[3] led to its service introduction slipping two years.

However, in service it was found that while pressure was maintained even at low speeds and RPM, the first stages were stalling and this was causing significant vibration and fatigue issues.

Wright solved this by adding inlet ramps that closed off the outer portions of the intake at low RPM.

Nevertheless, along with the Martin B-57 Canberra, its original application, the J65 went on to power versions of the North American FJ Fury, Douglas A-4 Skyhawk, Republic F-84F Thunderstreak, and the two Lockheed XF-104 Starfighter prototypes.

Final assembly was carried out in a 768,000 sq ft (71,300 m2) portion of a purpose built plant in Willow Springs, Illinois.

XB-47D fitted with two YT49 turboprops and four-blade paddle propeller