Thanks. In my search I noted at a California Training field some machines which may have been those at LAX, but the photo is now lost in the ether. One must note that the USA in 1931 deemed the Army to be the major setting for aerial activity, with the Naval Air Service rowing along behind. In those days the United Kingdom was lingering with its April Fools Day 1918 effort, with a Fleet Air Arm of the Royal Air Force attached. I note the very sad state of the Army Air Corps Memorial at Middle Wallop, barely established and already in mild distress.
Hey-ho, OH I regret on the 26th Anniversary of my becoming a civilian.