The model is scaled at 1/10 of the full-scale dimensions. Linear dimensions are scaled by 0.1.
| Component | Full Scale (ft) | Model Scale (ft) | Model Scale (in) |
|---|---|---|---|
| Leg Length | 19 | 1.9 | 22.8 |
| Leg Chord | 10 | 1.0 | 12.0 |
| Leg Thickness | 3 | 0.3 | 3.6 |
| Triangle Frame Side | 80 | 8.0 | 96.0 |
| Triangle Frame Base | 40 | 4.0 | 48.0 |
Foam density when expanded: 2 lb/ft³. Volume for one model leg: 0.285 ft³ (34.1 cups total mixed foam).
Assuming a 1:1 mixing ratio by volume, each part (A and B): 17.1 cups.
Note: Use the same mold three times to make all three legs.
| Scale | Target Weight (lb) |
|---|---|
| Full Scale | 27,360 |
| Model | 27.36 |
Target weights are based on buoyant force from 50% submerged legs.
To simulate full-scale speed of 5 knots, pull the model at: 2.67 ft/s.
Derivation: 5 knots = 8.44 ft/s; scaled by √0.1 ≈ 0.3162.
To convert model drag force reading (in lbs) to electrical power for full scale (in watts) at 5 knots:
Constant = 11,450 watts per lb
Formula: P_full (watts) = 11450 × F_model (lb).
Example: If model drag force = 0.1 lb, then full-scale electrical power ≈ 1,145 watts.
Model roll period × 3.16 = Full-scale roll period.
Derivation: Period scales as √(length scale) = √10 ≈ 3.162.