The FB-22 was to have a maximum speed of Mach 1.92. While an early FB-22 concept featured no tailplanes, the design incorporated twin tailplanes and likely would have fixed engine nozzles as opposed to the thrust vectoring nozzles on the F-22. The design could also have been adapted to use a more powerful engine, such as the F-35 Lightning II's Pratt & Whitney F135, or the General Electric/Rolls-Royce F136. According to Air Force Magazine, the combination of range and payload of the FB-22 would have given the concept a comparable effectiveness to that of the B-2 armed with 2,000-pound (910 kg) bombs. This placed the aircraft in the category of a regional bomber, comparable to that of the F-111, as it was intended to replace the F-15E Strike Eagle and take over some of the missions of the B-1 and B-2. Range was almost tripled from 600 miles (970 km) to more than 1,600 miles (2,600 km), which could have been extended by external fuel tanks. With stealth, the aircraft's maximum combat load was to have been 15,000 pounds (6,800 kg) without stealth, 30,000 pounds (13,600 kg). Unlike the F-22, the FB-22 was designed to be able to carry bombs up to 5,000 pounds (2,300 kg) in size. Various figures give the payload of the FB-22 to be 30 to 35 Small Diameter Bombs this is compared to the F-22's payload of eight of such 250-pound (110 kg) weapons. The wing, which was around three times that of the F-22, enabled the storage of a much larger amount of weapons and fuel.
Instead, the company left the fuselage intact as it enlarged the wing to a more delta shape. With an early design, Lockheed Martin lengthened and widened the fuselage to increase the internal weapons load it was later found that doing so would have incurred a cost penalty of 25–30% in weight, materials and development. To this end, the company devised several concepts that saw significant structural redesigns with respect to the fuselage and wings, while retaining much of the F-22's avionics. One primary objective of the internal studies was to exploit the F-22's air-to-ground capability while keeping costs to a minimum. The F-22, while designed as an air superiority fighter, embodied some degree of air-to-ground attack ability. Experience gleaned from Operation Enduring Freedom in Afghanistan demonstrated the value of a bomber that could remain in theatre in the absence of surface-to-air missiles. In 2001, Lockheed Martin began studies on the feasibility of the FB-22 as the company sought to leverage the design and capabilities of the F-22 Raptor.