I need help with a 'hit and run' scene I am writing for a book. My main character practices Martial Arts. He is about to be run over, he turns to face the oncoming car - what position would he adopt? He practices WingChun
This is a perfect example to demonstrate the importance of getting out of the way of a line of attack, which is no doubt a martial arts concept. Surprisingly, it's not taught all the time, as evidenced by cheesy self-defense demonstrations.
Your position should be off the line of attack. Move side to side, or upward if you are so inclined to use acrobatics. But don't move backward or forward, with respect to the direction of the car.
One hell of a question. The faster the car's going the less practical any options will be. While my training doesn't cover such things, for the sake of offering something to write I'll list what comes to mind. The interesting situation is when there's just too little time to move outside the line of the sides of the vehicle:
when I studied hapkido we used to practice a jumping roll like this - basically, if you have enough time to make a small vertical leap, you could try to dive over the car - possibly aided by a foot or hand on the bonnet or windscreen to get extra height or start you rotating. Notice how the hands and arms are positioned to make contact with the ground first and land gently and smoothly into a roll.
if you have too little time to jump: I'd try twisting so the front of the car is pushing the backs of my lower legs forward - rather than breaking my knees - while sitting one bum cheek on the bonnet and leaning towards one side of the car, then straightening the legs: my thought is that if you straighten out the body with the axis of rotation (crown of head down through feet, arms either tightly by your sides or lifted out above your head) parallel to the front edge of the windscreen, there's more distributed impact and a chance you'll roll/slide up the bonnet then windscreen while minimising sudden impacts and your overall change of inertia: hard to imagine much control of the landing with this approach though: if you make it over the windscreen then you'll land behind the car: if the angle of the windscreen is too vertical or the car's going too slow or too fast you might smash into it without lifting clear, then you'll get thrown forward by the car: potentially nastier than rolling/sliding over it. This is more about understanding the way the body can get hit without being damaged too badly, and how it can roll/slide, rather than directly utilising any martial arts training.
No wing chun or other martial arts position will save you from serious injury or death from a car impact. Best case is you are elsewhere when the car arrives. You would want to move perpendicular to the direction the car is traveling, and put obstacles in the way to prevent the car from steering into you. If that's not possible, you would try to decrease the speed differential (run in the same direction the car is traveling) to reduce the impact.
It is possible. For example, like Tonny Ja jumping over a moving car. Sure, the car is slow moving and not aimed at him but it can be done.
When startled a typical thoughtless reaction would be a falling step to gain distance with one hand high and one low for cover. Alternatively, a more aggressive character might do as in Biu-Zee form and throw a maan-sau (asking-hand) to search for contact. Only after recognising the incoming threat is a car would they be able to make a more intelligent response.
The falling step would be backwards and to one side, he'd step into whichever ready stance the lineage use, typically one foot in front of the other. The hands would then go to most likely to a bong-sau (wing-arm) and tan-sau (palm-up hand) position.