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S-1-11B Weight and Balance

alexc

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Hey all,

We're at the stage of W&B for our S-1-11B, G-EWOK here in the UK, and as usual with the 11B there is hardly any information out there. This time around it's lack of CoG range information, so I'm hoping to gather as much information to help other 11B builders in the future.

The original W&B from Curtis for N11PU (attached) simply shows the most forward and aft loading, but does not contain any information in regards to tested CoG ranges. These figures are used:
  • Datum: 51.375" forward of the lower engine mount at firewall
  • Empty weight (sans oil): 1069.25lbs
  • Empty CoG: 59.302" aft
  • Forward loading: 66.42" aft
  • Aft loading: 68.99" aft
Remember those figures are not a tested CoG range from what I can see. Whilst doing some research it seems that the W&B for G-IIIV (the first 11B in the UK) managed to get some additional information in regards to a CoG range:
  • Aviat factory test 21/11/01:
    • Datum: 51.35" forward of the lower engine mount at firewall
    • CoG range: 59.5" to 69.5" aft
    • CoG range at the lower wing leading edge: 5.1" fwd to 4.9" aft
  • Aviat factory test 14/3/02:
    • Datum: 100" forward of the lower engine mount at firewall
    • CoG range: 116.74" to 120.06" aft
    • CoG range at the lower wing leading edge: 1.75" aft to 5.74" aft
  • N12PU:
    • Datum: Lower wing leading edge
    • CoG range: 0.00" aft to 2.00" aft
  • UK LAA TADS:
    • Datum: Lower wing leading edge
    • CoG range: 0.00" aft to 2.00" aft
The empty weight for N11PU seems a little on the light side, though not by much. Both G-EWOK and G-IIIV have come in strangely at the same weight, 1174lbs (532.5kg). Unsure what N12PU weighed.

So, 11B builders/flyers, are you able to share your weights, CoG datum and ranges please? That'd be really useful and I'll put together a spreadsheet for future reference. Thanks!
 

Attachments

  • n11pu-curtis-weight-and-balance.pdf
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