I don't think it is possible in the contemporary sense that you are proposing. However I had seen in another mod where there were commodoties you could buy that were called trade missions. I dont remember exactly how it worked, but it was something like you need to get these "insert commodity" to "insert base" in 5 minutes or the mission is failed. The payout was very high, but if you didnt finish in the 5 minutes or less the commodity expired.
<span style="color:#FF0000"><strike>RETIRED</strike></span>
ON MY WAY OUT OF RETIREMENT
I can already think of a way of exploiting that if you cant deliver it on time. Simply dock on a base, sell it, then buy it back. Hey presto, its got all its health again. Apart from this "technicality", that work around sounds pretty neat...
I remmember seeing the same "trade mission" commodities. The catch to prevent exploitation was that all other locations but the destination and purchase point baught them for like 1 credit and sold them for 1000. So there would be a large decrease in profit if you did what Mcneo suggested. The issue with this idea is that it seems like a forced trade route. I don't know, it kinda sounds appealing if they all have a time limit...
On Hamburg they have trade missions where you need to take a given commodity from base to base. Got extra money if you succeeded & anyone who stopped you (I think) got their own reward. Hardly anyone did it.
I think the uber-uber-train gives enough reward but I can understand why pilots want options.
it would be nice if those missions were even more complex - like :
pick up special VIP missions cargo at NY
fly to california and sell there for 5k - buy back for 1$ ( and only there ) - next stop is london - same procedure there, then kyushu, then berlin, then augburg and back to new york.
what you get is a nice little round trip with your VIP - sort of a sightseeing tour. and it would be something you could do in a smaller freighter or even a fighter if you wanne make money without blowing up others.