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Some technical aspects of the Raptor MK-1

Length 14.22'
Wing Span 21.4'
Canard Span 9.4'
Empty Weight 520 Lbs
Useful Load 380 Lbs
Fuel Capacity 32 US Gal
V stall 50 Kts
V max 245 Kts @ 110 HP
V ne 270 Kts
Stressed 12 G's
Fully Retractable Gear
Forward Hinged Canopy
All Composite Construction
Engine Option 1 - VW Type 4 (2600cc)
Engine Option 2 - Corvair 3100cc
HP 80 - 140
Best LD - 120 Kts
LD - 25:1
Min Descent - 90 Kts @ 410 ft/sec

I have up until now done an initial weight an balance exercise and determined that the ideal C_G to be at FS76.  The Neutral Point is located at FS 79.5. I have also analyzed the Eppler1230 airfoil against many others, but none have the desired L/D polars as it.  The Roncz R1145MS was also analyzed and proves to be the best so far for use as a Canard.

Here are the polars for the estimated Reynolds equation:

At this stage I am still having difficulty in determining the shift in NP due to the increase in C_l of the canard.  I used the formula as suggested by Hollmann, there seems to be an unusually large shift of the Center of Lift much beyond the CG.

Example:

The Canard needs to produce C_l 2.8 to maintain lift at 65_Mph.

Lift ditribution

More to come soon......!

I will appreciate any suggestions.