Icerigger is written by Foster and is set in his Humanx universe.
In it the (human) characters crash on a planet. The planet is covered in ice, with islands popping up from the once ocean. While there is a human base on the planet, they crashed on the wrong side of the planet and they are way to far to radio them. They end up having to work with some of the natives, first to survive, then to make their way to the human base.
I love this book and its two sequels for several reasons, first it does a good job of letting the world and it’s people unfold. Learning about them is a shear pleasure. The second thing is the interaction between the humans and the natives. The humans end up using their superior science to help the natives, how they were able to do so makes a lot of sense, and is not as easy as many authors would make it.
While not hard science fiction by any means it is also not as soft as is all to common in many books with FTL.