Constellation at Dayton, Ohio

Hi Mike!
Any excuse to put up a photo!
Here’s one I like, that was originally 2 Mb

Everybody’s watching football!
Except you, Ray Jade, and myself: I was just searching for the older threads containing the very instructions you have just written! Someone (perhaps myself) long ago asked for these instructions to be added to the FAQ, it comes up so often!

First mention of hangars in the USA:
http://www.pgparks.com/places/historic/cpam/3army.html
. . . the U.S. Army Signal Corps made preparations to open an aviation school at College Park, MD . . . In 1911 . . . A larger tract of land was leased, approximately “200 acres extending north along the Baltimore & Ohio Railroad property to a series of goldfish ponds and east to the Paint Branch of the Anacostia River, with a maximum cleared runway of 2,376 feet in an east-west direction.” The Army Quartermaster Department leased the field for $325 per month and erected four temporary wooden hangars 45 feet square along the railroad track . . .

Extract from my personal database

Hughes H-1. Exchangeable short and long span wings. With short span, set new closed-circuit speed record of 352 mph on September 13, 1935, pilot Hughes.
Modified as 1-B with 1 000 hp Pratt & Whitney engine, 280 gal fuel tanks and new 32 ft wing as 1936 Bendix Trophy entrant, but Hughes withdrew. With long span wings set new transcontinental record of 332 mph average on January 19, 1937, pilot Hughes. Re-engined with 1 100 hp Pratt & Whitney in 1937. Appeared in 1940 film “Men Against the Sky”. Total flying time only 40 hours. Stored at Hughes factory, Culver City, California.
Donated to National Air & Space Museum, Washington, DC in 1975, displayed with long span wings.

Yes, it was destroyed and in any case the prime mover of the project (see my post #7) was unfortunately killed, so there is no chance of a rebuild.

I think that international civil markings were agreed at the International Air Navigation Convention in Paris, to come into force on 22 July 1919. An interesting overview of British and Commonwealth markings is contained in the introductory chapters of the British Civil Aircraft Registers series of books.