sin

sin() — DESK

SLING
ANGLE.

Two-leg bridle. θ from height and length. Tension from sin(). Compare T to the tag. Bookmark this URL. Print the numbers you just ran. Open once on a network — the desk stays on this device when the trailer Wi-Fi is dead.

Open once on a network. This desk stays on the device after that.

Last reviewed: September 5, 2026

HOOKTTWθHORIZONTAL
θ is the sling angle — from the sling to the horizontal. Not the angle between the two legs.

01 — θ FROM THE TAPE

θ = SIN⁻¹ (H / L)

H / L
0.500
sin(θ)
0.500
θ FROM HORIZONTAL
30.0°

02 — T FROM SIN()

T = W / (2 × SIN θ)

θ FROM THE TAPE30.0°

sin(θ)
0.500
1 / sin(θ)
2.000
T PER LEG
4000

03 — COMPARE TO THE TAG

T ≤ WLL

SAME UNITS AS WTAG

Optional. Read the sling tag after hitch and angle — not before.

Two equal legs. Centre of gravity in the middle. Vertical lift. θ from the horizontal — not the angle between the legs. H is hook centreline to the load connection. L is along the sling. This is the tag WLL. Choker and basket still apply. Three- and four-leg: if the load can tilt, design as two legs carrying.

Two-leg bridle. Factor = 1 / sin(θ). T is for W = 4000 in the same unit.
H / LθSIN θFACTORT IF W = 4000WHAT IT MEANS
0.50030°0.5002.004000Floor. Each leg sees W.
0.70745°0.7071.412829Working bridle.
0.86660°0.8661.152309Steep. Lower tension.
0.96675°0.9661.042071Almost vertical.
1.00090°1.0001.002000Vertical hitch. No spread.

https://sin.ae.org/sling · Printed copy uncontrolled · Last reviewed: September 5, 2026

sin(). Current version on this site.Work done to CSA Z150 / Z248, WorkSafeBC, BC Crane Safety and the rest — not an endorsement.