Airplanes and helicopters are the most usually found aircrafts. Still, pilots are hard to find and most of them will try to escape when faced with an undead invasion. Thus, it is better to be prepared in advance, have an acquaintance who knows how to operate an aerial vehicle. You yourself can take flying lessons, they are not that expensive anymore!
Helicopters are the way to go, they can land almost anywhere unlike there airplane friends, require less fuel to scout areas since you don’t have to fly in circles; you can just hover in a desired area and observe.
While hovering you will find dispatching zombies more easier than while flying over them. Imagine this: You land your airplane on an airfield, refuel it, check for other supplies and all of a sudden find yourself surrounded by zombies. If you have a small Cessna like airplane, you will probably seriously damage it while mowing the runway.
Note: there are a lot of helicopter types but they are usually 2 kinds of helicopters.
Piston engine and turbine engine helicopters: although piston engine helicopters can normally carry less weight they should be your preferable choice of escape since they can run on almost any fuel (jet, kerosene, diesel), but with a high price to pay since it will slowly damage the engine. But if you’re in an emergency, you’re in an emergency!
Boats and ships are quite slow but are still more preferable to speed boats. Speed boats make too much noise, use a lot of fuel and when you’re out of fuel can only float.
While docking to an island the whole zombie population of that island will hear you approach and attack instantly. The problem is, you can’t make a fast getaway in any water vehicle besides a speed boat and they usually can’t hold that many cargo or people.
What you’re looking for is a ship, a cruise ship to be precise. Modern cruise ships are like cities. They have their own waste disposal systems, can purify water, have lots of shop-works (electronics, wood, metal and even sewing shops). Zombies can’t exactly jump on cruise ships since they usually have only two or three entrances and are quite tall (several stories). The entrances use narrow bridges which are an ideal choke point in case of a zombie attack.
Many say that a sailboat is the way to go. OK, but only if you have a an expensive luxury sailboat with water purification systems and solar/wind energy chargers.
Still, the sailboat can not be used as a “fort” against zombie attacks while docking to shore and are not made of metal; keep that in mind.
If you wanna travel by land, go by foot or bycicle. The less noise you make the better is the moto on land!
Do not use a regular car, cause it will brake down after you hit a few zombies with it or accidently hit a barricade. Offroad vehicles are better but be careful, just because the commercial says it’s an offroad vehicles doesn’t make it so; civilan hummers for example are a piece of shit, they can’t mow down people and can’t really go offroad.
Jeeps are a safer bet than modern SUV’s and the like. Do not use buses, use trucks instead cause they are more ressiliant and thus can punch through baricades more easily. A crossroad motorbike is more preferable to any other engine land vehicle.
You can go almost anywhere with it, it requires less fuel and is more easier to abbandon (being swarmed by zombies in a broken down military hummer is almost the same as being swarmed by zombied in a broken down miata; nowhere to run) when you find out that using a motor vehicle is not the way to go in a zombie infested world.