These drawings are not offered as plans for pitch blocks or intended as such, they are only to show an idea we have had to attach the rotors onto a boomtrainer with the minimum of hassle and get consistent pitch. The reason for this is that due to space restrictions the blades will have to be unshipped each time it is used, and rigging the blades each time intrudes into training time. Conventional blocks use the same 4 bolt layout with the blade bar rotating around a centre pin and the horizontal bolts tightened up when the blades are pitched correctly, Our idea of having a small clearance slot on the hub bar blocks and the blade bar projecting into this slot with jacking screws top and bottom is to be able to set the pitch of the rotors to optimum position then lock everything up. On removal of the blades, undoing either the upper or lower jacking screw but leaving its opposite untouched the main bolts can be withdrawn. Refitting the blades should then be a case of locating the blade on its pivot pin and between the 2 jacking screws, lightly nipping up the bolts and tightening the loosened jacking bolt and finally tightening the main bolts. This is the plan ,will it work in practice, and will it be consistent ? If not there is still sufficient material to machine back to convert to normal pitch blocks and use on the boomtrainer. The clearance holes for the horizontal bolts has been left open because we don't yet know how much angle is going to be needed on the blades, ( it will be a case of opening them up gradually to get the smallest clearance possible) The pocket milled in the hub bar blocks is 5/16" wide and we are guessing that 0.090" will be deep enough to allow the required rotation of the blade bar. Note: These drawings are not offered as plans ,the information contained is just a record of our ideas.