as a gas barrier for the air sample. At takeoff the armored vessel hung in a deflated form around the steel cable (#27) and below an open parachute (#23) that would provide braking of the system descent if the rate exceeded about 2000 feet per minute. Launching of this complex balloon system required special handling techniques, and the entire process was referred to as a platform launch, a novel concept developed by Harold E. Froehlich, principal engineer of the Balloons and Meteorological System Group. In this form of launching the load train, nearly in length, was laid out on a ground cloth-covered runway with the lowest part of the load train in the upwind direction. The uppermost part of the system, the top of the lifting balloon, would be in the downwind direction. A heavy platform was positioned at a point toward the top of the lifting balloon, and the balloon material would pass over the platform and be securely held in place by a large horizontal padded roller about four feet in length. The helium inflation tube was located in the upper portion of the lifting balloon so that the helium source would inflate the section of the balloon beyond the platform. Since the system would be ascending to in altitude, only about 3% of the maximum balloon volume was filled with helium. The inflation took place by metering in an amount of helium lifting gas that would equal the gross weight of the system plus typically about 5% of ‘free lift’ to ensure that the system would ascend at an appropriate rate at the launching. Launching was initiated by releasing the padded roller on the launch platform. The ascending balloon would then sequentially pick up the lower part of the lifting balloon, the deployed parachute and armored vessel, the uninflated envelope, and lastly the heavy insulated bag containing the controller, blower, instruments, telemetering equipment and power supply. There were variations of this procedure that evolved to facilitate the launching. For example, the heavy instrument bag and blower assembly was eventually mounted on the front of a vehicle that drove under the balloon system as it ascended during launching, and the bag was released from the vehicle using small explosive devices. Grab Bag flights were typically launched early in the morning and recovered during daylight hours of that same day. The ascent time to was usually about three hours.