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In airscrews in which each blade root has an annular flange adapted to be secured to the hub, a clamping ring is provided which is secured by bolts parallel to the blade axis. The airscrew blade 1 has flange 2 which is held against the hub 3 by means of a sectional flange 6 secured by bolts 5. The flange is provided with projections or serrations 12 adapted to interlock with pins 10 on a metal bridge piece 11 secured under two adjacent nuts 8,. The nuts 8 are tightened to give to the bolts 5 an initial tension slightly greater than the maximum centrifugal force obtained when the airscrew is running. Beneath the flange 2 is disposed a sleeve 13 for positioning the flange with respect to the hub, and this sleeve is formed with an eccentrically disposed outer edge so that by adjusting it the blade may be set when balancing the complete airscrew.