The Defiant Agents by Andre Norton

"A tiny sound--perhaps the scrape of a boot on a ladder. Travis edged back into a compartment. A flash of light momentarily lighted the corridor; the approaching figure was using an electric torch. Travis drew his knife with one hand, reversed it so he could use the heavy hilt as a silencer. The other was hurrying now, on his way to investigate the burned-out engine cabin. Travis could hear the rasp of his fast breathing. Now!"

Alien technology scavenged by U.S. and Russian scientists has started a race to colonize planets outside our solar system, but the U.S. scientists are losing the race. In a desperate move the U.S. government decides to use a group of Apache volunteers in an experimental attempt to colonize a primitive planet, but before they can even begin their spaceship crashes on the planet Topaz...

You can view more about this title at the CruGuru website. It is available from Amazon.com and from Lulu.com. ISBN: 978-1-920265-08-3