Kent Barstow Aboard the Dyna Soar by Rutherford Montgomery - 1961 1st Edition.

It's so interesting to read early science fiction adventure stories.  So happy to have found this. 

It's all about Kent, an Intelligence Officer,  who tracks down clues and breaks up dangerous rings.  He joins the crew on the Dyna Soar's test flight.

Had to get this book.  Couldn't resist the name Kent Barstow!

This book lived in a library.