The biggest danger and greatest fear for any balloonist attempting to cross the Atlantic, is ending up in the ocean without a life jacket or life raft. This was precisely Lindstrand's predicament. In the cold Atlantic waters he would only have survived a few more minutes.
One of Branson's concerns about parachuting, besides his inexperience, was his altitude. But in fact others have skydived from higher, much higher. In 1960, Joe Kittinger, a US Air Force Captain, took part in an experiment to see if it was possible for astronauts, in pressure suits and with oxygen, to survive jumping from very high altitudes. Kittinger rode a balloon up to 31,333 metres before bailing out. His freefall lasted four and a half minutes and he reached a top velocity of 982kph before eventually opening his parachute at 5486 metres.
Jet streams can also cause clear air turbulence (CAT), the leading cause of in-flight injury on passenger planes. CAT can occur when a plane gets caught up in erratic air currents that occur in cloudless air. It can be caused by the wind velocity gradients on the periphery of jet streams where rapidly moving air is close to much slower air. These gradients are extremely difficult to predict or detect and can produce violent updrafts and downdrafts.
