If I cough when driving a car, do I protect the others better by covering w/ my hand or aiming at windshield?

My thought is that my hand deflects the air back towards the passengers quickly, whereas aiming at the windshield is more likely to keep them out of harm's way. What is the safer method?

The safer method has you not compromise control of the vehicle, barring that covering your mouth to deflect the brunt of the cough into your hand and down is best.

Covering your mouth does not stop all the germs but 'catches' many on your hand as opposed to shooting them out in all directions. In a car the germs can travel out and be caught up in the air currents throughout the car from vents, open windows, people breathing etc.

Open the window, and aim out side

Neither, you should always cough into the crook of your elbow. Then, the germs are on your shirt, or arm, instead of in the air, or on your hand, thus reducing the spread of the germs.

but to answer your question just as posted, cough into your hand, your head will block the air. if you cough at the windsheild, the air comes out in a spray pattern, and gets everywhere not just on the wiindow.

Use a handkerchief you slob...

If your wearing a tee shirt,
lift up the neck to cover your mouth.
then all the germs etc
stays inside your shirt.

Aiming at the windshield could cause an accident and kill all the passengers.... you might not be able to see out, ya know.