Original sources of the 1947 Roswell Balloon and Mogul Episodes
This trip was made in support of Project Helios. The primary purpose was to visit present or potential suppliers of materials need for the project. A major point of interest is the view on plastic films under consideration for the balloons. Pliofilm still seems to have most potential; nylon and polythene (polyethylene) are nowhere near mature enough to be seriously considered.
Since 1946 when the first plastic balloon program was started at General Mills, our engineering staff has been extremely interested in the prospects of contributing to stratospheric manned flight experiments. On project HELIOS, a gondola and balloon system was designed and built. In subsequent years, tremendous improvements in plastic balloon systems have taken place. This proposal covers the design and fabrication of two gondolas and of two balloons. It is planned that one gondola will be instrumented and flown unmanned on a 128 TT balloon to an altitude of approximately 90,000 feet. The second gondola would be a demonstration flight with a human observer to 115,000 feet on a balloon of 2,700,000 cubic feet capacity.
This report describes the first outdoor inflation and flight attempt of a full-size pliofilm balloon on April 24, 1947. Purpose of the test was to obtain data on (1) proposed method of inflation; (2) use of plastic ground cover; (3) behavior of the aerostat at low wind velocity; (4) weighing off the aerostat; (5) rate of ascent; (6) operation of appendix; (7) excess lift for safe take-off without dragging; (5) balloon suspension system; (9) behavior of suspended parachute. Several preconceived opinions on these points were found wanting. A suspension harness failure precluded an actual flight. Nevertheless, the experiment was very revealing, producing information vital to any future attempt. Prior to the first outdoor inflation, a trial inflation had also been successfully made at the balloon loft.
Between June 1946 and May 1947 the contractor has designed and built the gondola and auxiliary equipment for Helios to within 75% of completion, and has tested and built seven large, and several small balloons made of various plastic films. Through trial and error it has been shown that the present design will fly if the proper plastic film is used. The ideal balloon material has not yet been found, but an adequate plastic film, polyethylene, is now in production and 500 lbs. of this film will be available for assembling in June. A balloon which loses practically no lift in twelve hours has been developed. It has a diameter of 70 feet and a volume of 165,000 cubic feet. By stressing the cellophane-taped seams, it is possible to use a film of lower tensile strength and keep the weight of each cell below 100 pounds.
The New York University Balloon Group was organized in November, 1946 to develop and fly constant level balloons that would carry Army Air Forces' instruments aloft for the long range detection of nuclear explosions. In 1947, while awaiting the delivery of the polyethylene balloons to be used in these flights, tests were made using clusters of neoprene, meteorological sounding balloons. In June, flight operations started in Alamogordo AAF, NM where three full-scale flights were launched. One of these, NYU Flight #4, was last reported over Arabela, NM. From a recent examination of the Weather Bureau winds aloft reports and of the ground tracks of the two subsequent NYU flights, it appears that Flight #4 is a likely candidate to explain the debris later recovered north-northwest of Arabela
N.B. The 1940s Project Helios should not be confused with the recent Helios Project
The full reports from which these excerpts derive may be found at our UFO web-site.