My guess is the Airco DH-10.
Verifying information for a specific "almost was first" is near impossible, unless you are privy to a very specific source.
I noticed a peculiar thing about verifying the specifics regarding the history of an aircraft such as this, that is, each source has a slightly different slant, or even biase, on a same basic story, depending on the author's perspective.
For instance, in the old profile publication, printed in the UK, in their record of the German fighter ace, Werner Voss, in his final combat with British SE5's, they wrote off the German fighter ace's ability to make flat turns and quickly face an opponent as "sloppy half-spins", whereas Arch Whitehouse in his book Fighting Wings recorded that Voss' ability to make a 180 deg turn without aelorons was an amazing feat that enabled him to in fact put holes in each and every plane in the British squadron before they finally got him.
Tom
Tom T
“Failure is the opportunity to begin again more intelligently.”-Henry Ford
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