On the topic of space flight and disasters, one thing that always interested me was the lost cosmonauts.
In the early days of the space race, for political and propaganda reasons, the Russians covered up many missions that were not deemed successes. Yuri Gagarin was likely not the first to orbit earth, he was just the first one the Russians could brag about returning successfully and therefore hailed as the first. Others were not so lucky and burned up in the atmosphere or crashed. Some may have been prevented from returning because conditions would have led to them landing in foreign territory.
http://www.lostcosmonauts.com/default.htm