ORIGINAL: proulxlaw
I will not buy another product from CMP until they step up and resolve the issues that I had with one of their planes. Below is the email that I sent directly to:
[email protected] at CMP. The email was sent yesterday afternoon and so far I have received no response.
Dear Sir/Madam:
A couple of weeks ago I purchased on ebay a Zero .50 that is a CMP product. I assembled and balanced it per the instructions and have had serious problems with how it flew. There are either design flaws in wing incidence with the plane and/or the recommended CG is way off. I just got back from the field from the second flight which ended with the same result as the first. The plane went in after a brief flight which exhibited that the plane was extremely tail heavy. On the first flight I balanced the plane at 95mm from the leading edge of the main wing at the fuse w/o any adjustments for downthrust and left the plane 1-2 ozs. nose heavy. On the second flight, I balanced the plane 5mm closer (90mm from leading edge of main wing at the fuse) to the leading edge of the wing than the shortest distance in the recommended CG range (95-110mm) in the instructions and left it about 1-2 ozs. nose heavy and added 2-3 degrees of downthrust.
This is frustrating and obviously a problem with either of the above. I have built and flown successfully nearly a dozen warbirds to date and I have experienced problems with CG before but, none so bad that I couldn't get the plane in to correct the problems.
I had purchased 2 of these planes and still have 1 in the box which has not been started yet. I was also planning to purchase in the near future an FW190 and a Spitfire but, I will not buy another of your products if you don’t address and resolve the above stated problem. I will wait to review this plane on RCU until you respond and this matter is resolved.
Bob Proulx
Jackie @ CMP is at Hong Kong. They have a 1/2 day time difference. This is not something CMP can give you a brief response about. I have the larger Zero 120, and it flies great on the instruction CG. Zero's in general will end up tail heavy, due to its short nose moment and long tail moment. You usually have to use a heavier than recommended engine, or add a lot of nose weight. Maybe the smaller CMP warbirds are inherently unstable because of the higher wing loading. Well, make it nose heavier, at about 85 mm to see what it does. Or perhaps your control throws were too large.
Anyway, you can check out my CMP Zero 120 video here:
http://www.pedrofrigola.com/Zero.wmv