I was flying with an aircraft that was still in the break in phase. Anyway, I had my hands full with trimming it out as a very experiencd pilot was testing out a new students aircraft that was a high wing, I think it is called a parasol wing (looks like a bipe without the bottom wing). He was doing fine until he brought it in close for a slow flyby for a visual check on something. At the same time, a nasty gust of crosswing blew the model into the pilots stations. Fortunately, I had a guy helping me who happened to spot this as it happened. He is considerably larger than me, and very calmly put his hand on my back and said, "Bob, we're gonna move this direction real quick" and he gently shoved me to safety as I flew my plane. The very experienced pilot did not panick as many would have. Instead of cramming the thottle in an attempt to get out, he hit the throttle chop, and banked it into the run up stand about 30 inches from where I had been standing before I was ushered to safety. He did yell a warning, and apologized profusely. I certainly had no hard feelings. If you are wondering, the weight on the nose fell off, causing the plane to be extremely tail heavy. The flyby was an attempt to see what fell off just before landing.