Robart retracts for H9 P51-d
the spring air 116 retracts set is about $120. they use a standard servo to operate the air valve. this gives you a similar setup to the original wire retracts that come with this plane.
you can make both types work- but its easier to get air retracts set up and working.
the 700 series is set up to accept the oleos directly which is much easier than the set screw/grinding hassle.
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