Showtime 4D 90 center of gravity
#1
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From: Linwood,
MA
There was a review done by RC Universe about the Showtime plane. In the review there were pics of the inside of the plane showing the fuel tank moved back up against the fiberglass wing tube holder. Mounting directions from the factory have the fuel tank up in the nose against the firewall...and the CG measurement being 7 1/16" from the wing tip. My question is...with the fuel tank being moved back, have i changed the CG significantlly enuff that the 7 1/16" from the wing tip is no longer an accurate measurement for balancing the plane? Could really use some info from someone that has the same fuel tank location set up...Thanks.
--Paul.
--Paul.
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From: Manassas,
VA
Im not quite sure what your problem is. However, I also own the showtime 4d and i also placed the fueltank against the wing tube. With the servos in the tail, and the saito 125 up front i got it to balance at the recommended 7 11/16th with no prob. I think this the perfect setting for me that is.
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From: Linwood,
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Hi Nathan,
I just wanted to make sure I didn't create a CG problem by moving the fuel tank. I was more concerned on how the plane would react when the tank was full. Factory CG info supplied is based on the tank being up in the nose. I'm new at this...and this is the 1st time I've made some modifications to the building instructions. I set up my servos the same way you did, and I have a Saito 150 installed. I did do a quick CG check, and my plane balanced out fine with a 5 cell 6v battery placed straight down from the top of the angled end of the canopy hatch. If the tank move works good for you...can't see why it wouldn't for me. Thanks for the reply!
--Paul.
I just wanted to make sure I didn't create a CG problem by moving the fuel tank. I was more concerned on how the plane would react when the tank was full. Factory CG info supplied is based on the tank being up in the nose. I'm new at this...and this is the 1st time I've made some modifications to the building instructions. I set up my servos the same way you did, and I have a Saito 150 installed. I did do a quick CG check, and my plane balanced out fine with a 5 cell 6v battery placed straight down from the top of the angled end of the canopy hatch. If the tank move works good for you...can't see why it wouldn't for me. Thanks for the reply!
--Paul.
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From: Corona, CA
This plane flys very well at the recommended CG. Mine is about 3/8" aft and it's still a *****cat. Moving the tank will not change the location of the proper CG for the airframe. It may require some minor adjustments, but the proper CG location for any given airframe is, for the most part, a constant. (I think you are asking if the tank modification alters the 'optimum CG point...it does not0.
Have fun. This is a very good airframe.
(I really can't believe that word was 'asterisked'-out) How *****, *******,****** and ******* paranoid can you be? (just kidding)
Have fun. This is a very good airframe.
(I really can't believe that word was 'asterisked'-out) How *****, *******,****** and ******* paranoid can you be? (just kidding)



