A while back I wrote of my idea of having planes not instantly exploding at the instant of touching the forest. Mike (Storebror) vastly improved upon my crude and simple approach. The result is that a plane entering a forest will travel some distance through the canopy, slowing and accruing damage. It's even possible to pull out and continue flying, conditions permitting and if one's reaction is quick enough. But it was the case that upon dropping to the 25% forest height threshold (4m for the 16m tall forest) a plane always blew up.
Well, I've just revisited that code again, this time with an eye toward affording a chance of survivability if the speed is sufficiently low at the point of reaching that 25% height threshold. At the moment I have the algorithm structured such that at a speed of 20m/s and less the plane makes it to the ground without exploding. Between 20 and 40m/s (~40 to 80kt) the probability of destruction increases from 0 to 100%. I may further refine things, perhaps simply extending or adding an additional randomization so that no matter how slow, the plane could still explode.
Another benefit accrues when belly landing, for instance. While sliding across the ground and entering the edge of a forest, the aforementioned speed-dependant survival probability applies. No more Insta-BoomTM when merely touching the forest at low speed! The same goes for taxying, although damage will(?) occur (I'll have to test that.)
In this way, one need not fear so much when going down over a forest under control. If the speed is reasonably slow and the entry angle not steep, there is a chance of surviving.