As mentioned in the report, getting a marshaller can prevent an accident like this. No marshaller available, then at minimum, inspect the planned taxi route prior to taxiing on it and minimize the time between inspection and actally taxiing along the route.
Summary:
The aircraft was parked outside a hangar, in an area where construction works were ongoing and temporary buildings had been erected in preparation for an event. The pilot boarded the aircraft and started the engine, before beginning to taxi. After moving off the aircraft turned through 90° to go between buildings towards the runway. The width of the area between the buildings was insufficient to allow the turns necessary for the pilot of a Stearman to see the area ahead. The pilot saw one helicopter parked ahead on the left, and another on the right, but could not see directly forward, and the propeller and nose of N56200 contacted the front of a Robinson R44 helicopter which had been parked between the other two.
The pilot of N56200 immediately realised that there had been a collision, and shut down the aircraft, she and her passenger vacating it without difficulty. The helicopter was not occupied, and no injuries resulted, but its cockpit was destroyed. The collision could have been avoided if the pilot of N56200 had ensured that the area into which it taxied was clear of obstructions, either by observation, or the use of wing-walkers or marshallers.