I agree with danpost and MatheMagician, but I have another tip: improve the smoke the airplane 'drops': it isn't at the right place and when the plane is going down, the smoke is also going straight down. It should go like this:
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but with an angle of 45 degrees, since you're also moving forward.
2012/2/8
2012/7/18
2012/7/18
2021/3/13