descent. Parachutes with cross-shaped canopies have been employed in scientific
ballooning almost exclusively by Raven Aerostar (the company that manufactures
them). Apart from a time in the 1960’s, they were rarely used for scientific balloons. Although they performed well in all respects and were less subject to oscillation than flat canopies, they were never preferred over the flat canopies.
3.2.2 Raven Aerostar
Raven Aerostar’s recovery parachutes have performed reliably on thousands of
balloon flights conducted by NASA, Loon, government entities, and other space
agencies around the world. These parachutes are especially designed to recover
payloads from altitudes up to 48.7 km (160,000 ft). In fact, at 3,629 kg (8,000 lb)
Raven Aerostar’s payload recovery parachute holds the record for the heaviest
payload recovered from a stratospheric balloon flight.
The parachute allows for a controlled descent, landing and payload recovery
when a balloon is ready to be taken out of service. In the event of an unexpected
failure, the parachute deploys automatically.
Fig. 3.3 Raven circular payload recovery parachute. Photo courtesy of Raven Aerostar
3.2 Parachutes 39