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```32    REPORT NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS

[[image - drawing of an aircraft showing the forces and moments]]

Positive directions of axes and angles (forces and moments) are shown as arrows]]

[{5 Columns}]
Axis Designation | Axis Symbol | Force (parallel) to axis symbol | Moment about axis Designation | Moment about axis Symbol | Moment about axis Positive direction | Angle Designation | Angle Symbol | Velocities Linear (component along axis) | Velocities Angular

Longitudinal | X | X | Rolling | L | Y→Z | Roll | φ | u | P

Lateral | Y | Y | Pitching | M | Z→X | Pitch | θ | v | q

Normal | Z | Z | Yawing | N | X→Y | Yaw | ψ | w | r

Absolute coefficients of moment C [sub] l = L/qbS (rolling) C [sub] m = M/qcS C [sub] n = N/qbS (yawing) Angle of set of control surface (relative to neutral position), (sigma). (Indicate surface by proper subscript.)

4. PROPELLER SYMBOLS
[column 1]
D, Diameter
p, Geometric
p/D, Pitch ratio
V [sup] t, Inflow velocity
V [sub] s, Slipstream velocity
T, Thrust, absolute coefficient C [sub] T = T/pn [sup] 2 D [sup] 4
Q, Torque, absolute coefficient C [sub] Q = Q/pn [sup] 2 D [sup] 5
[/column 1]
[column 2]
P, Power, absolute coefficient C [sub] P = P/pn [sup] 3 D [sup] 5
C [sub] s, Speed-power coefficient = [sup] 5 SQRT(pV [sup] 5/Pn [sup] 2
(nu), Efficiency
n, Revolutions per second, r.p.s.
(phi), Effective helix angle = tan [sup] -1 (V/2(pi)rn)
[/column 2]

5. Numerical Relations
[column 1]
1 hp. = 76.04 kg-m/s = 550 ft-lb./sec.
1 metric horsepower = 1.0132 hp.
1 m.p.h. = 0.4470 m.p.s
1 m.p.s = 2.2369 m.p.h
[/column 1]
[column 2]
1 lb. = 0.4536 kg.
1 kg = 2.2046 lb.
1 mi. = 1,609.35 m = 5,280 ft.
1 m = 3.2808 ft.
[/column 2]```

Transcription Notes:
[sub] = subscript [sup] = superscript