Field limited: the airfield is on flat ground, but there's a river at the end of the very short runway. Doesn't matter how fast you can climb, you're not going to get off the ground before the end of the runway unless you reduce your weight.
Climb limited: the runway stretches for miles, but there's a bl00dy great tall building just off the end of it. Doesn't matter how long the runway is, it's not going to help you get over the top of that building unless you can climb faster.
FFF
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