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Old 11th Sep 2021, 15:42
  #326 (permalink)  
The Sultan
 
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SB-1 FLRAA Proposal Submitted

It has been rather boring in the waning days of summer (coming not too soon) until this gem dropped on Verticalmag:

https://verticalmag.com/news/sikorsk...x-to-u-s-army/

This has a number of things to comment on:

“Today, Team DEFIANT completed and submitted the proposal for the U.S. Army’s FLRAA competition
Amazing that for the first time in the FLRAA program Sikorsky-Boeing actually met a schedule. Proves they are better at writing fiction than they are at program management and cutting metal (actually molding composites).

“We’re very excited to be at this point. It’s been a long journey in a very short period of time.”
It has been EIGHT years since the FLRAA concept demonstrators were selected. Five years is a normal development cycle so where did the "very short time" come from?

Army’s need for an advanced rotorcraft capable of at least 230 knots and preferably capable of cruising 280 knots, much faster than traditional rotorcraft.
Data gathered in the ensuing flight test campaign, including level flight at 230 knots, was incorporated into the team’s FLRAA proposal.
Defiant X delivers speed where it matters
This ignores the original goal of the FLRAA requirements to have a 250 kt minimum cruise speed. The final requirements were changed once the shortfalls of the SB concept were known. What does "speed where it matters" even mean? For a long range assault aircraft (the LRAA in FLRAA) where high speed matters is in the cruise segment of a mission getting to the objective. This shaves hours off a mission. Where does SB think speed matters more?

while operating in the same footprint as the BLACK HAWK,
Was that a requirement in the final RFP? If it was? Why? Who cares?

Defiant X also has a tricycle-style landing gear with one wheel under the cockpit and two wheels aft whereas the operational prototype Defiant sported two front wheels and a tail wheel that protruded down from its tail boom.
What!!! The original concept made sense as it at least tried to keep the pusher prop out of the dirt. Going to a nose gear can only be a last resort to move the cg forward to reduce rotor loads at the sacrifice of operability. You strike the pusher on the ground flaring into a hot LZ, you are there for the duration.

Relative to the images released is it just me or does the gap between the rotors been significantly increase?




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