Simon Cheshire 
Airlock [PDF ebook] 

George and his friends have won an incredible prize, the chance to visit the
Berners-Lee space station for a special overnight school trip. But after less than an hour in space, a devastating explosion rips through the orbiting platform, killing most of the crew and leaking almost all of the station”s air supply into space.
All the evidence suggests deliberate sabotage, which means the terrorist must still be on board. But who can it be?
With time running out and little hope of a rescue, can George and his friends stop the saboteur, save the space station,
and survive?