1947-era documentation relative to the Roswell affair of July of that year is not non-existent. It is, however, certainly rare. One piece of documentation - not of military origin, but which came from a German citizen in the immediate wake of the controversial affair - is worth noting. It's a curious and interesting letter, to be sure. It was written by one Heinz-Adalbert Ahuis (see this link for information on Ahuis). At the time, he lived at 23 Asnabruck, Hansa-Str. 7, in what was then the British Zone of Germany. In his letter, which was sent to the American Embassy, and that was marked "Strongly Secret!" Ahuis wrote:
"Dear Excellency: "Last few weeks in American and German papers I read much about the so-called 'flying discs' (or 'flying targets') that are said to be seen suddenly coming up in some states of your country, and that are disquieting your publicity so much. I would like to examine more accurate the type that came down near Roswell (New Mexico). Please, do also take this matter as serious as it really is, and do not think it a vision."
Ahuis continued: "Just concerning this I am an expert. I am very skeptically as to the 'calming-explanation' of Brigadier General Roger Ramey and others, who say that these disks are merely meteorological observation-balloons - or supplements of them - etc. I am interested in this business very much, and so is the American Army, I am sure. In connection herewith and in order to explain my odd wish, Excellency, I must inform you of the following."
Ahuis got to the point of his communication: "Since 1929 till the end of the war by the way as a hobby I occupied myself - completely interested in sport only - in developing flying-models of all kind and shape, chiefly sail-planes and rocket types. Sailplane-soaring was and still is my favorite sport. With my researches in 1936, among others, I met also the idea of the 'flying disks' and pursued it, considering it already at that time once to be of any importance. Later I searched into the qualities of this model in connection with rocket-experiments, and about the good result I was extremely surprised. (Nowadays we could already use atomic power, too).
"I found, that my models of a 'flying disk' - in smaller and bigger size - 1.) for the investigation of the sphere, 2.) for military aims, and 3.) for the air-traffic of the future could and presumably will play a not too undervaluing figure, and in many a point even it will be superior to all other planes and rocket-projectiles, including the German 'V-2 - rocket' you know already; for I think it possible, manned_disks 1.) to fly every course we want, and 2.) to and safely again, (what we cannot absolutely affirm 3.) the most rocket-constructions know until today)."
Ahuis signed-off: "I am ready to continue my researches and developments of such a kind of disk-models and disk-planes (as well as still other very interesting ones) on a place in U.S.A. that seems fit for that purpose. Perhaps I may come and see you once to talk about some details necessary?"
To what extent - if at all - Ahuis' letter was followed up on remains unknown. Maybe, he just wanted to get the hell out of war-torn Germany and he used his UFO-themed letter as a form of leverage. We'll probably never know.