a parachute, which is then attached by steel suspension cables to the payload. A flight is terminated by firing an explosive squib which separates the parachute from the balloon. A rip line simultaneously tears open the top of the balloon. The balloon quickly deflates and falls to the ground, to be retrieved and disposed of (balloons are single use). The payload descends, suspended by the parachute, and is recovered by the ground crew. Conventional payloads typically have a float duration at altitude of 72+ hours. Long Duration Ballooning payloads float at durations of 42+ days. Ultra long duration balloons (ULDB) are being developed which can operate at float for +100 days. The limiting factor is the diurnal cycle of the sun, rising and setting. Heat during the day causes the balloon to expand and gain altitude, thereby losing helium. Heat loss at night causes the balloon to sink and contract. Ballast is carried to overcome the effect. Flying in a polar region during full sunlight allows more negligible altitude variations. ULDB balloons or superpressure balloons (SPB) are sealed to prevent helium loss and have a pumpkin shape at flight altitude. The SPB TRAVALB-2 surpassed previous Antarctic balloon flights by staying aloft for 149 Days, 3 hours, and 58 minutes after launch from the NASA Long Duration Balloon (LDB) site at LDB Camp, McMurdo Station, Antarctica. The operation was supported by National Science Foundation and United States Antarctic Program. After the Travalb-1 launch abort, the Travalb-2 lifted off on 29 December 2019 to test NASA balloon trajectory predictions in Antarctica and to study electron losses from Earth's radiation belts. Preparation, Launch, and Flight A balloon flight involves both the CSBF and a scientific team(s). The CSBF determines the launch site based on scientific goals, and provides local preparation facilities, a balloon(s), launch and recovery vehicles, and personnel to support the logistical aspects of pre flight, flight, and post flight activities. Scientific teams ship a payload to the launch site, and set up a small field station to assemble their equipment, make last-minute preparations, and manage the experiment during flight. The payload is typically a large instrument or cluster of instruments, plus onboard computers, radio telemetry equipment, and ballast. Launching a balloon requires the conjunction of light low-level winds (to comply with the limitations of the CSBF dynamic launch technique) and suitable upper-level winds (so the balloon remains within telemetry range of