The X-49A is based on the airframe of a Sikorsky YSH-60F Seahawk, but utilizes Piasecki's proprietary vectored thrust ducted propeller (VTDP) design and includes the addition of lifting wings.

The concept of the experimental program was to apply the VTDP technology to a production military helicopter to determine any benefit gained through increases in performance or useful load.

The "SpeedHawk" aircraft includes an SPU (third engine), high forward-swept wing concept, a 45-inch "fuselage plug" cabin extension, and several other drag reducing and performance-oriented improvements, including a rotor hub fairing, landing gear streamlining, and a fly-by-wire flight control system.

[4] In 2013, it was reported that Piasecki Aviation had made plans to use the VTDP design of the X-49 for their entry in the Future Vertical Lift program,[5] but were not chosen when that project moved into its Joint Multi-Role Technology Demonstrator (JMR-TD) phase.

[8] The cockpit controls were modified with the addition of a manual propeller pitch override on the collective lever for the ring tail.

The weight added to the X-49A demonstrator aircraft is estimated at 1,600 lb (730 kg) due to the requirement[citation needed] to not modify the existing mechanical control system.