Weight & Balance Software

[proscalemodels]

Hey Folks,

Would someone be willing to share the W/B (with your numbers) software they are using on their JT2 ? Or maybe just the worksheet for a JT2 W/B



Much Appreciated,

John
N701SY

[blaswichk]

I did a fresh w&b on my Gull 2000 a few months ago, and Mark and Mike of Earthstar sent me the moment arm chart and w&b ranges for all Earthstars. It was an eye opener as the previous owner had used the “J”, JT2” stations for the moment arm figures, and the correct figures put me at the back of the cg range. All is better now.
kb

[cossitt.alan]

Unless you've built your airplane from scratch, I'd suggest all owners
measure the actual arms to verify them against the specifications. I found
that I had a variation of the JT2 that added a couple of inches to the
length of the second seat and this moved the wing edge etc. back about 1".

-Alan

[proscalemodels]

That is exactly what I am doing now on 701SY. All previous records and documents were apparently destroyed by water damage during the builder's possession of the aircraft. I am the 3rd owner. Even my log books for the aircraft and engine were created new a few years ago. I have no construction drawings, or documents of any type for this aircraft. Not even aircraft operation limitations doc's.

So I am looking for others with a JT2 of any configuration of engine/air frame/prop etc... to hopefully donate their W/B worksheets so I have something to compare my newly measured numbers and weights on my own aircraft. I especially need to know what is the designers/manufacturers designated location for where exactly the CG is on a JT2. Either as related to the wing leading edge, or ARM with a stated datum 0 location to measure from etc...... or something verifying where exactly the CG is "supposed to be measured from" and what is the FWD and AFT measurements of the CG limits.

I am trying to get the FAA to send me a full copy on disk of all the documents sent or issued by the initial DAR for the initial registration and sign-off after aircraft manufacture.

The plane fly's now a little tail heavy with full fuel. I will not fly a passenger until I get the W/B nailed down.

Thanks everyone,

John

[cossitt.alan]

This should help. This PDF construction manual includes the W&B worksheet
Mark came up with.

[proscalemodels]

Your stated suggestion has been exactly my thinking as well from the beginning, and is what I am currently doing. all from scratch. But it makes life so much easier to be able to at least compare what others have come up with for the same aircraft model since no plans or specifications seem to exist that I am aware of. If there is some plans and spec's out there somewhere... please let me know where I can possibly obtain a copy. Also... If I can at least get the location exactly for the designers CG location with fore/aft dimensions for the JT2 would be of great help, and obviously needed for a proper W/B calculation.

Thanks again for your reply,

John

[cossitt.alan]

sent out a post with the construction manual attached. The manual has the
W&B calculations as suggested by Mark for all the J models. If that did
not come through let me know and I'll send it directly to you.

-Alan

[proscalemodels]

Most excellent... that is what I have obviously been needing from the start. Thanks a million! If you have anything else to share with regards to the JT2 documents etc..., I would most humbly request you please forward it my way.

Much Appreciated,

John

Thanks to Everyone!

[proscalemodels]

Thanks!

Wonderfull news. It's what I have been hoping for... you have made me a very happy camper indeed.

Much appreciated!

John

[proscalemodels]

Hi Alan,

Thanks again for sending a copy of the manual.

Since the Assembly Manual is for a "J" single seat model, and not a JT2 model... Are we to use the CG location of 15"/21" from leading edge as stated in the J model manual... for the JT2 model as well? Because, all the datum points indicated in the J model manual are obviously much different to the measurements I have made on my JT2 aircraft using the 0 datum point of the tip of my nose cone. Or, do I need to reset my 0 datum point further ahead of my nose cone to match the J models CG datum measurements?

Thanks,

John