US Army evaluators tasked with selecting the service’s next troop-carrying helicopter found that the Sikorsky-Boeing proposal lacked sufficient design detail to be considered.

New details related to the army’s Future Long Range Assault Aircraft (FLRAA) programme were revealed in a 13 April report by the US Government Accountability Office (GAO), an independent federal auditing agency.


Source: Sikorsky-Boeing

The Sikorsky-Boeing DefiantX lost the Future Long Range Assault Aircraft competition to Bell’s V-280

As a result of a design deficiency, the army board charged with choosing between the Sikorsky-Boeing DefiantX and Bell’s V-280 Valor proposal deemed the Sikorsky-led design “unacceptable” under service programme requirements, says the GAO’s report.

“The [army] found that Sikorsky’s proposed architecture was insufficiently detailed, including, most unequivocally, that it did not allocate functions to several subsystems,” it says.

The “unacceptable” designation was not related to the DefiantX’s actual flight performance. 

Bell in December won the FLRAA contract, a deal the army estimates could be worth $70 billion over decades. The service ultimately plans to replace its fleet of 2,300 Sikorsky UH-60 Black Hawks with the FLRAA design.

However, Sikorsky parent Lockheed Martin challenged the army’s choice, triggering a review by the GAO. Details about the army’s decision had been kept from the public until now.

The GAO formally denied Sikorsky’s protest on 6 April, says the report, which confirms the army’s assessment, solidifying Bell’s win. “We conclude that the army reasonably evaluated Sikorsky’s proposal… as technically unacceptable.”

While flight-performance details remain undisclosed, the GAO says the army assessed Bell’s tiltrotor design as having superior performance to Sikorsky’s compound-coaxial design.

Notably, the DefiantX was assessed as being substantially cheaper than the V-280 – costing just over 50% the price of Bell’s proposal. But the GAO notes that the army essentially considered that price estimate to be unusable.

V-280 in US Army green

Source: Bell

Bell’s V-280 tiltrotor is set to replace Sikorsky’s UH-60 Black Hawk as the US Army’s utility lift and troop-carrying helicopter

“While [Sikorsky’s] proposed price is lower, the offer is based on an unacceptable engineering design,” the GAO quotes an unnamed army official as saying.

That official, identified only as the “Source Selection Authority” (SSA), did not find a similar issue with Bell’s submission.

“[Bell’s] proposed price, in comparison to the design’s [independent government estimate], is reasonable and provides the best value to the government,” the SSA said in the original contract decision.

The GAO notes that under published standards for the FLRAA competitive selection process, the army weighted performance and engineering designs as more important than cost.

Sikorsky, in its protest, disputed the army’s conclusion that its plans were insufficiently detailed, alleging that the service applied different standards to the two bids.

During its more than three-month review of the case, the GAO says the army used the analogy of architectural blueprints for a house in describing a critical flaw in the Sikorsky-Boeing submission. 

“Sikorsky’s proposal provided something similar to a drawing of what the house looked like on the outside, a basic indication of the size and shape of the house,” the army told GAO auditors.

“Such a picture did not provide the functional detail that the army required, showing what the space would look like on the inside (ie, how the system functions would be allocated to different areas of the system – for example, that food storage and preparation would be allocated to a space for the kitchen),” the report notes.

The GAO says the army used fair and appropriate criteria in assessing the radically different designs.