```html

Seastead Scale Model & Full Scale Specifications

Fraude Model Scale: 1:10 | Fluid: Caribbean Sea Water (64 lbs/cu ft)

1. Structural Dimensions

Triangle Frame (Above Water)

Parameter Full Scale Model Scale Model (Feet/Inches)
Front-to-Back Sides (2) 80 ft 8.0 ft 8 ft 0 in (96 in)
Back Width (Beam) 40 ft 4.0 ft 4 ft 0 in (48 in)
Height (Apex to Base) 77.5 ft* 7.75 ft 7 ft 9 in (93 in)
*Calculated: √(80² - 20²) = 77.46 ft

Float Legs (3x Wings/Struts)

NACA profile extrusion, 50% immersion

Parameter Full Scale Model Scale Model (Inches)
Leg Length (Vertical) 19 ft 1.9 ft 22.8 in
Chord (Fore-Aft) 10 ft 1.0 ft 12.0 in
Width (Max Thickness) 3 ft 0.3 ft 3.6 in
Submerged Draft (50%) 9.5 ft 0.95 ft 11.4 in

2. Foam Mixing Instructions (Per Model Leg)

Assumptions: 2-Part Polyurethane Foam, 2 lbs/cu ft density. Assumes 1:1 volume mix ratio and a yield of approximately 4 cubic feet per gallon of mixed liquid (conservative estimate for 2lb foam). Adjust if your specific product has different expansion characteristics.
Volume per model leg ≈ 0.315 cubic feet (based on NACA 0030 profile, ~55% of bounding box)
Required mixed foam: 0.315 ÷ 4 = 0.079 gallons = 10.1 fluid ounces total
Component Volume (fluid ounces) Volume (Cups) Volume (ml)
Part A 5.0 oz 0.625 cups (5/8 cup) 148 ml
Part B 5.0 oz 0.625 cups (5/8 cup) 148 ml
Mix total: ~1.25 cups to produce ~542 cubic inches of expanded foam. Add 10-15% extra to ensure mold filling.

3. Target Weights (Displacement)

Weights represent the total vessel displacement at 50% leg immersion in Caribbean seawater (64 lbs/cu ft).

Full Scale Displacement = 3 legs × (19×10×3×0.55) cu ft × 0.5 × 64 lbs/cu ft
Model Displacement = Full Scale ÷ 10³
Vessel Target Weight (Displacement) Notes
Full Scale ~30,000 lbs (15 tons) Includes all structure, ballast, and payload to achieve 9.5 ft draft
1/10th Scale Model ~30.0 lbs (13.6 kg) Total model weight including ballast to achieve 11.4 in draft

Note: The foam legs alone (full scale) weigh ~1,890 lbs total. The remaining ~28,000 lbs is the triangle frame, equipment, and internal ballast needed to submerge the foam legs 50%.

4. Towing Test Parameters

To simulate 5 knots full-scale speed using Froude scaling:

Model Speed = Full Scale Speed ÷ √λ = 5 knots ÷ 3.162 = 1.581 knots
1.581 knots = 2.67 ft/s = 1.81 mph = 0.81 m/s

Target Tow Speed: 2.67 feet per second

5. Power Scaling Constant

Convert measured drag on the model (in pounds) to required electrical power for full scale at 5 knots:

Watts_full = Drag_model_lbs × 11,450
(Example: If sensor reads 0.5 lbs, full scale needs ~5,725 Watts or 7.7 hp)

Derivation: Power scales by λ^3.5 (10^3.5 = 3162). Model Power (ft-lb/s) = Drag × 2.67 ft/s. Conversion: 1 ft-lb/s = 1.356 Watts. Constant = 2.67 × 3162 × 1.356 ≈ 11,450.

6. Roll Period Scaling

To determine the full-scale roll period from model observations:

Full Scale Period = Model Period × √10
Full Scale Period = Model Period × 3.162

Example: If the model rolls with a period of 2 seconds, the full scale will roll with a period of ~6.3 seconds.

Assumptions: NACA foil volume calculated as 55% of bounding box (0.55 × chord × thickness × length). Foam yield assumed 4 cu ft/gallon mixed @ 2 lbs/cu ft density. Seawater density: 64 lbs/cu ft.

```