Purpose of the flight and payload description
The STRATOLAB manned balloon program was born in middle 50's when the US Navy refloated a previous project from late 40's called Helios and managed by balloon pioneer Jean Piccard. It included the construction of a sealed rounded capsule, which was comissioned by the Navy to General Mills Inc., a balloon firm from Minneapolis responsible at the time of their Skyhook unmanned balloon program. After the cancellation of Helios, before making any flight in 1948 the gondola was stored at the Lakehurst Naval Air Station until the project was resurfaced seven years later as project Stratolab.
The objective of the program was to conduct research in aerospace medicine, collect geophysical and astrophysical measurements and evaluate military techniques and equipment for flight at extreme altitudes, using personnel as observers, as inexpensive servomechanisms for scientific instrumentation or simply as test subjects. Unlike the other manned program of the time -Air Force's MANHIGH- the STRATOLAB effort included allways a two men crew and three flight profiles: low and medium altitude ones to 12.000 ft and 40.000 ft respectivelly using an open gondola and the high altitude ones using the sealed gondola which reached the stratosphere itself. The scientific Officer of the project was Lieutenant Commander Malcolm D. Ross while Navy Captain Normal Lee Barr, MD, was the flight surgeon.
The system used in the medium altitude flights consisted of an open gondola for personnel, similar to that used in the low level flights along with a larger balloon, as the system would reach altitudes nearing 40.000 feet.
Aside the instrumentation to sense and indicate altitude and rate of climb or descent, the major difference was the addition of a suitable oxygen supply and cold weather clothing for the crew.
As ocurred in the low level systems a simple valve in the top of the balloon, controled manually or electrically from the gondola and an appropriate amount of ballast (sand or iron dust) allowed vertical control of the aerostat.
Because the gondola was open and its size and shape were easily varied in accordance with experimental requeriments there was a large amount of flexibility in the size, shape and weight of scientific instruments which were used by personnel in the gondola.
Another addition was a cargo parachute for use as an automatic safety device in case of a balloon failure. It linked the balloon with the gondola serving also as load line.
Details of the balloon flight
Balloon launched on: 9/24/1956
Launch site: University of Minnesota Airport, New Brighton, US
Balloon launched by: General Mills Inc.
Balloon manufacturer/size/composition: Zero Pressure Balloon General Mills
End of flight (L for landing time, W for last contact, otherwise termination time): 9/24/1956
Balloon flight duration (F: time at float only, otherwise total flight time in d:days / h:hours or m:minutes - ): 6 h 15 m
Landing site: Near Cresco, Iowa, US
This was the second flight of the Stratolab Low program using a open gondola. The tripulation was composed by two civilian researchers from General Mills Inc. Keith Lang and Harold "Bud" Froelich.
The objective was to evaluate the balloon system, personal flight gear and to make studies about the weight of various papers, wind direction and scatter patterns for leaflet drops.
Life support consisted of standard oxygen breathing masks. The balloon reached an altitude of 42.150 feet entering at the time to the Guinness Book of World Records for the highest manned flight ever made with no artificial pressure environment.