I'm trying to find a YA novel that I read sometime between 1977 and 1980 from our public library (after I started reading "big books" in second grade, but before we moved from that town). Two notes:
We lived in a small town in Iowa (USA) with an underfunded library that had a lot of older books, so I strongly suspect that this novel may have been written any time from the late 40's on. This library had many books which had been written in the 1920's and 1930's.
Although I was definitely under age 10 when I read it, it was more-than-likely written for YA, since that's where I gravitated to in the library at the time (unlike the school librarian, whom I referenced in this post, our public librarian was very much an enabler for me in this pursuit - giving a shout-out to Mrs. Brown!).
Plot points that I remember include:
A boy (early-to-mid teens) was in a small plane with either his father (a businessman) or his father's pilot.
The plane crashed in a mountain wilderness; pilot was killed, boy survived.
Boy was rescued and nursed back to health by an old man. (Note: I seem to remember that the old man had been part of the Klondike gold rush in the 1890's, but I'm not certain).
By the time the boy was healthy enough, it was too late in the year to hike out before winter, so plans were made for the boy to winter with the old man and hike out in the spring.
Boy learned how to survive a mountain winter from the old man.
Old man died during the winter, boy survived alone until spring.
In the spring, boy was found by a search plane.