sr falson used to be a .60 size airplane ,how much does your plane weigh,what size wheels are you using?when sitting at rest is the chord line of the wing level with the ground,pointed down torwards the ground or pointed up.I have a feeling you are using wheels that are too small and the nose gear strut is too short.on a grass field minimum wheel size should be 2 3/4 longer grass means larger wheels.also the plane will take off easier if the nose gear is lengthed a bit so that the plane sits slightly nose up.I flew a 5 1/2 pound falcon 56 on an os 35 r/c for 2 years back in 1970 off a grass field and these things helped.