There are times when I'm driving a very heavy freight train up a steep hill, the weather changes and my train grinds to a halt, but the game won't let me spawn a loco at the rear of my train to help me get up the hill. I would like an additional spawn option that will allow me to spawn a loco inside my block that a can couple too
Good suggestion actually. Run 8 allows you to do this if you find yourself struggling, though you usually have to spawn a little distance behind. I remember having to do it with a heavy consist up to Trona. Stalled out just before the tunnel at the summit. Spawned in a couple of SD40’s, drove them to the rear of the train, jumped to the front, got everything set up via the tick box and away I went, the two helpers then stayed with the train and became spare power for outgoing trains at Searles Valley.
The problem is doing that on the fly in the moment when it is necessary. The spawned loco would need to be setup to provide power and need to be coupled to the rear, it's not just a simple spawn like we currently do with the free roam spawning tool. Quite complicated to implement I guess. What would help and probably would be easier to do is provide an extra amount of force, when hitting dedicated button. Something similar to the "Reset Vehicle Physics" option.