Drawings.MarinePropeller.pdf

1.0795 0.000

1.0795 H 280 N 4

2.54

985.0 22.00 0.710 22.00 0.710 31.00

2.58

DAR 0.83

a 0.829 a s 6.09

I 0 24.2

K 0 T 1.1348 U f 0.69 W 7.9375 S 1.0 K 1 13 w 0.27 f 85 C n 0.1000

C s 0.6761

A 12.51

B 50.32

C 1289

Prop strength; ABS Steel Vessels, 4-3-2; 9.1 t 0.25 = S [ K 1 { AH / CnCRN } 1/2 ± (C s / C n ) (BK / 4C) ] t 0.25

Minimum thickness at 25% radius Rake correction; (aft rake: +, fwd rake: -) Corr'd minimum thickness power at rated speed, HP number of blades

R engine rpm at rated speed gear ratio shaft rpm at rated speed

P 0.25 pitch at 25% radius pitch / diameter at 25% radius

P 0.70 pitch at 70% radius pitch / diameter at 70% radius

D propeller diameter, in.

propeller diameter, ft.

EAR

area of expanded cylindrical section, 25% R moment of inertia of expanded cylindrical section, 25% R, about CG parallel to nose/tail rake, at blade tip, +aft maximum section thickness, 25% R max distance, tension side to neutral axis expanded width of section at 25%R 1.0; D <= 20 ft

(4300wa/N ) (R / 100)2 (D/20)3

(1 + 1.5P0.25)(Wf - B) coefficient, US; 13, MKS; 289; SI 337 material constant, 0.27; NiBrAl material constant, 85; NiBrAl

I 0 / U f W T 2 a s / WT

1.0 + (6.0 / P0.70) + 4.3 P0.25