From what I remember I designed and built this 36" span RR Eagle DH4 during 1960 when I was still a teenager. I still have it, this picture was taken last year.
I started from a beautiful 3 view scale line drawing published in an 1960? Aero Modeller and it was intended to be free flight with a Mills 75 up front.
The trusty Mills could even manage the scale 8x4 four blade prop wood.
With more or less true scale construction (and wing section!) before completion I converted it to C/L on the grounds that at least it would not be able to fly away!
At just 8oz all up it was really too light for C/L so quite a few years passed (8 no less) before I had the time and opportunity to try it out as a rather scruffy University student. A fellow student keen on photography took the pictures.
And it did fly.
Note the rather slack lines.
Just after this photo was taken a gust caused the lines to go completely slack and the DH flew sedately over my head with the line drag exactly balancing the rudder off set. Not wishing to pull off the wings I simply followed the plane and gradually took up the line tension. It then continued as a normal control liner until the fuel ran out!
Apart from the out of scale grass it could almost be 1917.