fokkerc2

C-2 Military transport version of the Fokker F.9, powered by three 220 hp (164 kW) Wright J-5 radial piston engines, accommodation for two pilots and 10 passengers; three built in 1926 for the US Army Air Corps en.wikipedia.org/wiki/Fokker_F.VII

The aircraft serving as the backdrop to this photo is the Atlantic-Fokker C-2A named "?" ("Question Mark"), USAAC Serial Number 28-120, which, due to aerial refueling, was able to set an endurance flight record of over 150 hours from January 1 - January 7, 1929. The aircraft's commander (Carl "Tooey" Spatz) and crew of officers (Ira Eaker, Pete Quesada, and Harry Halverson) would go on to be important leaders of the US Army Air Force during the Second World War, and afterwards in the US Air Force. See: en.wikipedia.org/wiki/Question_Mark_(aircraft)

Distinguished aviator (then-) Lieutenant Albert F. Hegenberger (US Army Air Corps) aboard the aircraft "Bird of Paradise," an Army Air Corps Atlantic-Fokker C-2 (itself derived from the Fokker F.VIIa/3m tri-motor airliner) (AAC Ser. No. A.C. 26-202) modified for long distance flight. The instrument just next to Hegenberger's left knee is an aperiodic compass (a.k.a. "deadbeat compass"), a compass which did not oscillate as an aircraft changed headings or was affected by turbulence.

Hegenberger and Lt. Lester J. Maitland (US Army Air Corps) would complete the first non-stop flight from the mainland United States (Oakland, CA) to Hawaii (Wheeler Field, Oahu) aboard "Bird of Paradise," from June 28–29, 1927.

A bit odd to come across this photo (and the photo below) in this most recent posted collection of circa-1921 Bain photos, though Hegenberger was involved with developing navigation instruments and techniques for the Air Service at that time. The "Bird of Paradise" wouldn't be procured until the 1926 Fiscal Year.

See also:
en.wikipedia.org/wiki/Albert_Francis_Hegenberger
en.wikipedia.org/wiki/Bird_of_Paradise_(aircraft)
Here's a photo from the San Diego Air Space Museum's (SDASM) collection on the Flickr Commons of Hegenberger (L) and Maitland (R) next to the aircraft: