V-280 wins US ARMY FLRAA contract

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Boeing Shows How the Defiant X Is Not That Different From the Black Hawk

It appears Boeing and Sikorsky have begun their media effort to overturn the Bell FLRAA contract award.

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Lacking any valid Defiant X performance capabilities over the V-280 to extol, Boeing and Sikorsky are left with insinuating the V-280 is to big to be compatible with existing US Army infrastructure. But is the V-280 size even an issue?


Based on scaling the images in the Sikorsky/Boeing video, the Defiant X is larger than the UH-60 Blackhawk. Significantly larger.

Using the Blackhawk main rotor diameter of 53' 8"as a reference, the Defiant X main rotor is approximately 59' 9" in diameter.

Using again the Blackhawk main rotor diameter as a reference for scaling, the hangar door opening shown in the video is approximately 62' wide. For worst case rotor position this leaves less than 14" clearance to the door opening on either side when towing the Defiant X into the hangar.

Indexing the Defiant X main rotor to as shown in the video reduces the aircraft width to approximately 56' 6", increasing door clearance to 33" per side. This would seem to be adequate clearance, but raises the question of how would mechanics index those two huge main rotors prior to towing?

The Bell V-280 Valor may visually appear larger than the Defiant X, but based on published data the V-280 is significantly shorter in total length. With the V-280's two main rotors indexed to minimize width for towing into a hangar, the aircraft is approximately 59' 4" wide (again based on scaling published data). For a hangar with a 62' opening, this provides 16" clearance on either side when towing the V-280 into the hangar. Note: On the V-22, manually indexing the two main rotors common procedure, performed from the ground with the pylons at 90 deg using a lanyard looped around a blade, or by hand with the pylons rotated to 45 deg to facilitate reach. I assume a similar procedures can be used on the V-280.

The ease in being able to manually index the rotors on the V-280 could also facilitate parking the V-280 in hangers with door openings smaller than the Defiant X would fit. By manually reindexing the V-280 rotors after the first blade passes through the hangar door, the effective aircraft width would be approximately 51'.

As far as footprint on the ground, as noted the Defiant X is significantly larger than the UH-60 Blackhawk. Just look at the relative aircraft sizes in the Sikorsky/Boeing video. Therefore, with maintaining the same rotor to rotor clearances used on the Blackhawk footprint, this claim appears to be a stretch. Additionally, ground footprint comparisons of the Defiant X to the V-280 need to take into consideration the different proportions of each aircraft.