My 14yo son is interested going on a summer missions trip to Mt. Kilamanjaro in Tanzania, Africa.  His mother is pushing him to go, but just sprung the idea on me.  Everything looks fine about the trip (reputable group with long, positive track record, worthy cause, etc.) except for one thing:  It is 8 weeks long.

In general, I'm the opposite of over-protective, and encourage my kids to try things.  When I was a kid, I had an awesome experience spending 3 weeks in Australia when I was 16, but I know I was getting homesick before the 3 weeks were up.  I'm struggling to see how 8 weeks away from family and friends (He would have others in his group) makes sense for a 14yo.

FWIW, My son has done great on week-long summer camps, etc.

Any thoughts on how to know if a long trip away from family and friends is appropriate for a teen?