George C

Could anyone who has flown the Global ultimate tell me what down and right thrust angles have used? The manual doesn’t say much and right trust on the firewall seems too much. I mounted the engine (Rossi 53) and the cowl was heavily asymmetrical (both angles) nothing like the photos of the built plane I have seen by other posters. I would normally expect to see something in the region of 2 degrees right thrust and 2 degrees down thrust.
Any help would be appreciated.

George C

rockmon

George I have around 2 degrees of upthrust in mine with a couple of washers but I left all the right thrust in and it flies great. It is a pain getting the cowl right with that much thrust but take some time and it comes out ok. I have run this plane with a Webra 50 and it needed a ton of weight in the nose so I switched to a Super Tigre 61, that cured the weight problem but I thought it still needed a bit more so I put a Thunder Tiger Pro 61 in and it turned it into a very fun plane to fly.

George C

Dear rockmon

Thanks for the information. I guess what I’ll do is set the engine –2 right and 0 down and start flying without the cowl and see how it goes. On first flight I’d rather have a plane wanting to go up than down. The only thing I’m a bit worried is how much will flight performance be affected by the absence of the cowl.
I’m still in the building process so I can’t say how tailheavy the plane could be but I have a unused super tigre 90 just sitting there with a bisson pitts muffler. If indeed you needed nose weight I think it is more or less the same weight and dimensions as your 61. I’m planning on using two 605’s for the tail and one standard servo for each side of the ailerons however I guess I’ll have to glass and pin the firewall. Do you think the airframe could handle the power? Anyway I hope I don’t have to throw most of the cowl away if I use the ST 90.

Oh! Did you fly the plane at –2 right and + 2 upthrust when you where using the webra too? I thing both the webra and the rossi are quite similar in weight and power. How was the vertical?

Not too many questions I hope!

Regards

George C

rockmon

George I don't think you will notice much difference in how the plane flys without the cowl on, I'm not sure why I think that but after you fly it you will see what I mean. I ran 425's for ele. and and rudder and 1 605 for the ailerons, I take it you are going to mod the ailerons and run two servo's, good idea when I put mine back in the air I plan on doing just that. It has been a while since I assembled mine and can't remember how much weight I had to add with the Webra but to me any extra weight is too much and that's why I went with a 61 on it. As far as the airframe being able to handle your 90 there is no doubt in my mind that it WILL handle it, the Ultimate is one of the best built arf's that I have put together that much I do remember. Make sure your battery and reciever are strapped down tightly, the ultimate will do some of the most violent snaps and spins I have ever seen and that's why I have not flown mine for a while, during a beautiful blender something came loose inside and I didn't have total control after the spin and I set it down in the top of a tree, it ripped the mount off on the bottom wing and loosened the cabanes in the top wing, very tough plane. I am thinking of a new wing kit because I'm not sure if the wing will hold up after any repair to the mount section. Yes I did have 2 degrees of upthrust on the Webra, that is automatic with me when I build any high performance plane and I can change it in a few minutes if it doesn't seem like the plane needs it, vertical was not real impressive with the Webra because of the extra weight needed for balance, different story with the 61. I didn't glass or pin the firewall I just added some corner round and a little extra glue and it was fine. Good luck, hope this helps and keep us informed on how it goes.

George C

That is great information, thanx. I’ll start flying it without the cowl and make any necessary adjustments then. About the aileron servos, I’ve just enlarged the standard mounting hole so that it can hold two standard servos mounted side by side. Now about the nose weight I’ll see how it goes and if everything moved forward and weight still needed, I’ll go for the ST 90

Regards

George C