High quality mechanicals like the ones from Frank Tiano Enterprises or Robart coupled with a JR 791 retract servo 260 oz.in. torque are very strong. The 791 retract servo moves very slowly.... It's still too fast for scale competition but it's better than most retract servos are.

Pneumatics are more durable and can be adjusted for very scale retract actuation speeds. The pneumatics are more expensive but they are worth the difference for .60 and up size airplanes. IMHO

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