I've added sling and hoist load abilities to a number of helicopters, and I helped add them to the MV-22 project that came out fairly recently.
It's not hard to do, really. It helps if the model has the appropriate additions to make the visuals even better, but it's not essential. You can add the hoist, you can arrange for internal carrying of the hoist loads, the slung loads location, and so on.
The big secret about it is to get the weights the bird is capable of correct, along with the cable strength, cable length, correct locations of the hoist points, and connect points for sling loads, things like that. It can take a little research to get the numbers all right, and as I said, the correct model additions help, but aren't essential. They are for the visual only.
The easiest way to add in the various different loads that the bird can then pick up and put down, or carry around, is to use AICarriers, but a set of large numbers of loads at various world locations is the make a saved flight with them all added in. That part I'm not very good at, as I use AICarriers to place a load or loads, then pick them up, carry them, and set them down.
Check out
https://docs.microsoft.com/en-us/pr...irectedfrom=MSDN#helicopter-specific-sections for detailed information. It's down near the bottom of the page.
I believe Jordan Moore also made some pages with information on the "saved flight" method of pre-placing loads in the world. Try Google. If you need, I can explain the AICarriers methods.
Does this help at all?
Pat☺