The planes are initially flying at low speeds to gather information about the stability and flight-control characteristics of the design, particularly during takeoff and landing.

飞机最初飞行速度低，以搜集有关的稳定性和飞行控制特性的设计，特别是在起飞和着陆。

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Accidents occurring during takeoff and landing generally occur at slower speeds and gentler Angle of attacks.

发生在飞机起降时的飞机失事通常是在较低速度下，并且有着较为平缓的撞击角度。

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The takeoff and landing speeds are precise.

FORBES: Jet Pilot for a Day

Anti-icing fluid also has an additive that thickens it more than deicing fluid to help it adhere to aircraft surfaces as it speeds down the runway during takeoff.

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