system
You are a chatbot acting as a human, specialising in Generation. Give a response that a human will want to hear.
human
Oh, great computer in the sky, can you explain the difference between a high wing and a low wing on airplanes? Why would one be preferable rather than the other? Why haven’t aircraft designers settled on a certain type that’s best?
gpt
There are a lot of engineering considerations that go into wing design. Different styles excel in certain situations but not in others, so there’s no one perfect design. The best configuration for a lightweight bush plane won't necessarily be the best for a massive airliner. Plus, high and low wings are not the only options. Here are a few of the key advantages and disadvantages that may help illustrate the situation:

-	All other things being equal, a plane with low wings will have a shorter takeoff roll thanks to the ground effect. 
-	The engine placement and wing placement are linked. Only large planes such as jet airliners can fit their engines in pods below a low wing. This placement makes it easy for maintenance crews to access the engine components, so it speeds up repairs. Smaller low-wing aircraft must carry their engines elsewhere; though the planes are shorter overall, that still often places the engines out of immediate reach to ground crews. 
-	Mounting engines low on a low wing does, however, increase the likelihood of ingesting foreign object debris (FOD) during takeoff or landing that can damage the engine. Some designs like the US Air Force’s C-17 mitigate this by mounting engines on high wings.
-	High wings are inherently more roll-stable. Since their center of mass hangs below the center of lift, these planes are unlikely to experience unexpected or uncontrollable rolling motion. It does mean they require more force to generate an intentional roll force, though.
-	In small aircraft, low wings limit ground visibility but improve overall visibility in the air. High wings do the opposite. 
-	Small low-wing aircraft can be hard for passengers to enter and exit.
-	A high-mounted wing usually leaves more available cargo space in the fuselage than a low-mounted wing.
-	Because the wings are closer to the ground, the landing gear on low-wing designs usually require less structure and reinforcement.
-	In-wing fuel tanks in a high-mounted wing can use gravity to feed fuel to the engines; low-wing tanks need fuel pumps. However, high wings are harder to refuel.
-	High-wing aircraft are more heavily affected by crosswinds than low-wing ones.