F-22 EMD (Block 1.0, 2.0, 3.0)

The EMD refers to the initial Engineering and Manufacturing Development aircraft used for testing, software development, and flight envelope expansion during the early stages of the program

These apply to the 9 EMD test aircraft (Raptors 4001–4009, tail numbers 91-4001 through 91-4009), built during Engineering & Manufacturing Development. They are not production configurations — they represent progressive stages of flight test and software maturity. All 9 EMD aircraft are externally near-identical to production F-22As.

While the overall layout was similar to the YF-22 prototype, the external geometry saw significant alterations; the wing's leading edge sweep angle was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%.[28] The radome shape was changed for better radar performance, the wingtips were clipped for antennas, and the dedicated airbrake was eliminated. To improve pilot visibility and aerodynamics, the canopy was moved forward 7 inches (18 cm) and the engine inlets moved rearward 14 inches (36 cm). The shapes of the fuselage, wing, and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. The internal structural design was refined and reinforced, with the production airframe designed for a service life of 8,000 hours.

Aside from advances in air vehicle and propulsion technology, the F-22's avionics were unprecedented in complexity and scale for a combat aircraft, with the integration of multiple sensors systems and antennas, including electronic warfare, communications, identification friend or foe (IFF).

The EMD contract originally ordered seven single-seat F-22As and two twin-seat F-22Bs, although the latter was canceled in 1996 to reduce development costs and the orders were converted to single seaters.

The first two were EMD aircraft in the Block 1.0 configuration for initial flight testing and envelope expansion, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the *Block 10 *configuration for development and upgrade testing, with the last two considered essentially production-quality jets.

Block 1.0

• Parent: Baseline EMD airframe
• Aircraft: Primarily Raptors 4001 & 4002
• Purpose: Initial flight envelope expansion, structural loads testing, engine/airframe integration
• What's different: Limited to ~80% structural load limits. Basic flight control software. No combat avionics — these were "flying structures" for envelope clearance. Raptor 4001 first flew 7 Sep 1997. Key limitation: Could not perform full-g maneuvers or weapons testing

Block 2.0

• Parent: Block 1.0 (same EMD program, next phase)
• Aircraft: Raptor 4003 onward
• Purpose: Production-representative structural testing
• What's different: 4003 was the first 100% structural loads aircraft — cleared for full-g flight testing, flutter testing, and high-AoA work. Still limited avionics. Represented the structural standard that production jets would be built to. Key milestone: Validated the production airframe could handle the full flight envelope

Block 3.0

• Parent: Block 2.0 (same EMD program, next phase)
• Aircraft: Raptor 4005 was first to fly Block 3.0 software (5 January 2001)
• Purpose: First combat-capable avionics software integration
• What's different: Full sensor fusion, APG-77 radar operational, ALR-94 electronic warfare suite active, AIM-120 and AIM-9 integration, CNI (Communications, Navigation, Identification) suite. This was the software baseline that proved the F-22 could actually fight. Predecessor to production Increment software. Key milestone: Proved the integrated avionics concept worked — the foundation for all production software

More info:

• War History Online - F-22