The Royal Canadian Air Force used to use old Lancaster bombers for search and rescue aircraft. They were chiefly used over water, though you have to remember that anything north of Edmonton is all water anyway…frozen and dotted with moose and missionaries, but that’s another story. The Lancasters were not armed while searching and rescuing, but we’re not so sure about the moose or the missionaries*.
The history retailer can also use this idea to gain material for sale. The trick is to fly out over the vast frozen wastes of the past and look for SOS signs in the snow. When you spot someone who was in trouble or had a grievance you can fly over to them and circle low until you can see whether there is any sign of life. If anything is moving, there is likely a dollar to be made.
Incidents, individuals, and group occurrences in the last few centuries can be very profitable if there is any echo from then until now. The actual thing that happened will not yield anything…unless it was the discovery of a gold-encrusted tomb of the someone…but if you can find survivors, relatives, acquaintances, or debtors of the dead, you can present a bill and demand payment. In some cases you’ll need to play to the desires and prejudices of the current generation regarding their ancestors, but as long as the originals are dead and gone, it doesn’t really matter too much what you say now – they rarely rise out of their graves and stalk you.
Beware, however, those descendants. If you say what they consider the wrong thing about great-great-Grandad they’ll fee a lawyer to sue you and then the shoe, sabot, or jackboot may well be on the other foot. It is always safest and most profitable to purvey and pander rather than expose and excoriate.
* There are reports of planes being lost over Edmonton but this is probably not true. The reputation of the place would have served to warn them off.