Big Stik CG and engine mount
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Big Stik CG and engine mount
I have just put my Great Planes Big Stik (.40 size) on the CG stand, it is modified to be a tail-dragger and has a heavy Rossi R45 motor to pull is along. I have the battery and radio as far back as possible (just in front of the servo mount) and am still finding myself about 1"+ too forward of the recommended CG (3-3/4" from leading edge). Way nose heavy. The engine is mounted with the recommended distance of firewall to prop thrust washer of 4-3/4". I could move the engine back about 1/2" which should improve CG matters a fair bit before adding ballast. Is there something magical about the 4-3/4" spacing to the thrust-washer or would this engine move be ok?
Obviously if I have to add lead weight ballast is it common to cut a hatch in the tail somewhere to install, any better ideas on getting lead back there? As it stands now (without the engine move) I need 3 oz of lead on the elevator to make it balence! So, some ballast will be needed even with the engine moved back somewhat.
Obviously if I have to add lead weight ballast is it common to cut a hatch in the tail somewhere to install, any better ideas on getting lead back there? As it stands now (without the engine move) I need 3 oz of lead on the elevator to make it balence! So, some ballast will be needed even with the engine moved back somewhat.
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RE: Big Stik CG and engine mount
My Big Stik 60 was the same way. I put it on the CG machine and the nosed dropped like it had an anchor tied to it. I moved the engine as far back as it would go and still had to add lead to the tail. It flew great eevn with the extra weight. I painted the flat lead weights red to match the covering and epoxied them to the fuse just under the elevator stab on each side. Looked ok. I hate to add dead weight but in this case no other option.
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