jettset99

My Feedback: (7)

Hi we had a Top Cat crash on take off the Cg was set as per intructions at 5" aft of the wing leading edge, it seemed as it was tail heavy and did a back flip on take off. Ayone know about the Cg is on this Jet .Thanks Paul

Thud_Driver

My Feedback: (1)

Did you measure down the leading edge or back along the root of the wing? The instructions indicate down the leading edge. This is about right. I have a ton on flights on mine with the Cg in that location. I have no idea why TGA would specify the Cg that way unless they thought you were going to "finger" balance it that way. The difference in the two methods would result in an aft Cg by slightly over 1 1/2" if measured along the root.

Also, which wing do you have? I did see one with the rectangular tapered wing ("sport wing"???) pitch up into a Cobra maneuver in the flare once. It recovered to a flat smack onto the ground.

Another TopCat was at the field today with the Cg as indicated and it flew fine. Banged up some on flight 3 due to a main gear problem.

jettset99

My Feedback: (7)

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Gordon Mc

My Feedback: (11)

I didn't actually see the instructions - was just asked whether I personally would interpret "5 inches back" as being measured from the wing LE or from the boom LE.

From what Thud_driver is saying though, the directions indicate measuring along the LE, rather than measuring along the root, which is a pretty substantial difference. I don't think I've ever heard of anyone specifying a CG that way before -- industry standard seems to be to quote it as a percentage or distance of root chord.

jettset99

My Feedback: (7)

Hi Yes Gordon, I was asked the exact same thing I never saw them eithier. I did get a copy of them and they do say 5 " down the leading edge someone messed up real bad on that one. Paul

Thud_Driver

My Feedback: (1)

Paul,

On my airplane, 5" down the leading edge puts the Cg about 4" in front of the main gear strut. Even measuring along the root would still put the Cg just ahead of the main gear tires on my airplane.

Gordon,

The instructions say: " The C/G is located 5" back along the leading edge of the wing. Start with this measurement. You can move the C/G back to fit your flying style." The problem is that the internal framing and the wing mounting allows for some fore/aft positioning, so it's possible the wing can be located almost +/- 1/2" fore/aft on the boom. I think my wing favors being forward and I'm sure my Cg is around 1/2" back from where recommended. But then, I haven't C/G'd the plane for a long time and I've added and moved some things around since. BTW, there are no drawings. Just instructions with a bunch of pictures.

Paul,

My gear plates had the retract unit mounted in the center (fore/aft) per the pictures. I'm not using trailing arm struts so my tires are actually centered on strut and not aft of it like in the pictures.

Sorry for the loss. The C/G instructions aren't the best and I would have preferred something more like a measurement from the tip of the nose so that you would know you're in the right place.

Rick

jettset99

My Feedback: (7)

Hi Rick thanks for all your input, The sad part is the Cg was set up right in the first place,The Hot spot is the same way you measure down the leading edge,it was a bummer but the owner understands what happened and thats whats important.Again thanks for your help ill be @ El Mirage in a week to test fly my New Rookie 2 @ 6:00 am stop by if you got some spare flying time. Paul

foster4u

My Feedback: (112)

Paul,
My topcat was one of the best flying planes I ever had for all three flights of its short life (stuck main gear, cartwheel, nose dug in...not good) The P70 from you ran great and there was power to spare, any one got another topcat? I need a new airframe for my P70.

Thud_Driver

My Feedback: (1)

Paul,

Is the airplane totaled or is it salvageable? Some guys up here might be interested if the fuselage is repairable.

Thanks for the inivite to El Mirage but I'm out of town this coming weekend. Do you fly there much and have your experiences there been good?

Rick

JohnVH

My Feedback: (38)

Foster, I have a Topcat that need a little work Id be willing to let go of.

foster4u

My Feedback: (112)

John, I sent you a P.M.

CARS II

My Feedback: (7)

Sad, sad.
Is any one doing something for this first time jet pilot, as I understand he went to B/W to get help from the jet guys, instead he end up with a total airplane, not only his first jet got totaled but his morale was crash along with the airplane [] [].

Very sad I think.

CARS II