Hey Vincent,
Glad to hear the Tiger flew so well on it’s maiden voyage. I think you are on the right track moving the CG back a little bit for a test flight to see if it improves performance. Looking forward to following along on the cowl “creation” as well.

I knew exactly what you were talking about as I read it - as I had a very similar experience with a 40 size build I did. It was an exceptionally light plane and it wanted to land fast simply because it would drop the nose. And, yes, I had plenty of elevator in it. I was perplexed as this plane should have been able to crawl. Anyhow, I started adding lead to the tail a little at a time. Got to the point where I was adding a ¼ ounce at a time till the airplane flew much better and I kept going, a little at a time, till the plane started getting worse. Then I backed up a bit…

If I may be so bold I would like to elaborate on the subject a little bit – to share with those that might be interested and/or those that have not had a chance to do much experimenting with CG’s. Not to mention any newer pilots that might be reading this thread- as the Tiger makes a really great second plane

First - a little disclaimer, every airplane is different. From my experience, wing loading plays a huge part in what you can get away with when playing with a CG. The type of airfoil has an effect (thick versus thin & the type - flat versus fully symmetrical) as well as the shape. Example: good ole Hershey bar wing versus a double taper swept back design. I have found that most pilots look at the plans/directions and set the CG – “balance point” to what is called for and some will set it with precision. Then like Vince mentions, they never explore the flight envelope by experimenting with how the plane flies when varying the CG– “balance point”. I actually prefer to use the term balance point because center of gravity goes so much further/deeper than how many inches back from the leading edge does you plane balance.

I actually did a write up in the build thread I did for the plane I mentioned above. On my little 40 size project the plane had a 500ish plus sq.in. hershey bar wing and weighed 3-3/4lbs. Should have been a real floater. CG was set to the rear of the recommended range. If I slowed it down, the nose would drop. I could hold the nose up with elevator, but the whole plane would drop. (the wing was stalling) As you would expect right….. But, again, this thing should fly all day long at just above idle and it wouldn’t do it. So, I took a whole flying day adding weight to the tail and do a test flight. Add more weight, do another flight and so on. When I was done I checked the balance point, documented it, removed the weight and shortened my motor mount till I re-balanced the plane at the documented point. In my case the balance point changed significantly. But as I mentioned, it was an exceptionally light wing loading.

There is a lot of info out there on the web about setting the cg or “balance point” of an airfoil. Some very technical and some not as much. With any new airplane, if one wants it to fly it’s best, there is a whole routine for setting the plane up that involves balance, thrust, travels, and you can go the extra step with incidence.

Well, I have babbled on long enough. I’d encourage anyone to experiment (within reason and in small steps) with their airplane. You might be surprised at what all you learn about your airframe and what it will do.

Anyway, Vince, I would love to hear the results of your balance point experiments on that fine looking airplane you have.