10.1 Vertical, Choker, and Basket Hitches

10.1 Vertical, Choker, and Basket Hitches

Quick Answer: A vertical hitch uses about 100% of the sling’s rated vertical Working Load Limit (WLL). A choker hitch typically rates about 75–80% of that vertical capacity (many tags and exam problems use ~75%). A basket hitch with both legs essentially vertical can rate about 200% of the single vertical capacity (two supporting parts), only when the basket is applied correctly. Always read the manufacturer’s tag for the hitch in use—never invent factors in the field.

Execution of Rigging Activity is the largest domain on the NCCCO Rigger Level I written exam (about 42%). Hitch selection is pure execution: same sling, three different hitch shapes, three different usable capacities. Level I assumes load weight, center of gravity (CG), and configuration are known or provided. Your job is to match hitch type to the load, stay inside hitch-specific WLL, and recognize when a “basket” on the drawing is not a true double-vertical basket.

Why Hitch Type Matters

A sling tag does not give one magic number for every wrap. Capacity is rated for specific hitches because geometry changes:

• How many parts of sling actually support the load
• How tightly the sling bends or cinches
• Whether legs share load equally and at what angle

These percentages are reference relationships used throughout training and exam problems. The tag always wins if it prints different hitch ratings for that product.

Vertical Hitch — 100% Reference

In a vertical hitch, the sling hangs so that the load is supported in a straight line between the upper connection (hook, shackle, master link) and the lower attachment (eye, shackle, lifting point). For a single-leg vertical hitch, usable capacity is the sling’s rated vertical WLL—the baseline for other hitch math.

Conceptual diagram (vertical)

        Hook / master link
              |
              |  ← one supporting leg
              |
         Load attachment
              |
           [ LOAD ]

When vertical is appropriate

• A rated lifting point or shackle can take a straight pull.
• The load will hang plumb without needing a choke to “grab” the package.
• You are applying a single-leg portion of a multi-leg bridle (each leg is still a vertical-style pull relative to that leg’s path).

When vertical is not enough alone

• Loose bundles that will slide out of a straight eye-to-eye arrangement.
• Objects with no bottom support for a basket and no dedicated pad eyes.
• Situations needing positive grip—then consider choker (with capacity derate) or a different rigging plan.

Worked example — vertical capacity check

Given: Synthetic sling tag: vertical WLL = 4,000 lb. Planned single vertical hitch load = 3,600 lb.

Step 1: Compare load to vertical WLL.
3,600 lb ≤ 4,000 lb → OK for vertical hitch capacity (still inspect, protect edges, and confirm crane/hook ratings).

Step 2: If the same sling were choked at 75% of vertical:
0.75 × 4,000 = 3,000 lb choker capacity. A 3,600 lb choked load would be over capacity even though vertical was fine.

That contrast is an exam favorite: hitch changes the number.

Choker Hitch — About 75–80% of Vertical

A choker hitch passes one end of the sling through the other (or through a choker fitting) so the sling cinches around the load. The tight bend and friction at the choke point reduce capacity. Industry practice and many manufacturer charts place choker capacity near 75–80% of vertical. NCCCO-style problems often use 75% unless a tag states otherwise.

Conceptual diagram (choker)

        Hook
          |
      (eye / loop)
         / \
        /   \  ← choke point (tight bend)
       |     |
       | LOAD |  ← cinched body
       |_____|

Why capacity drops

• Severe bending at the choke reduces effective strength of rope or webbing.
• The choke can create high local stress and abrasion.
• Uneven seating or a “half choke” can load the assembly unpredictably.

When a choker is appropriate

• Bundles of pipe, lumber, or rebar that need grip so pieces do not spill.
• Cylindrical loads where a basket might roll out without additional control.
• Situations where the plan calls for a choke and the choker WLL covers the load.

When to avoid or upgrade the plan

• Load weight is between choker WLL and vertical WLL (tempting misuse of vertical rating).
• Sharp edges at the choke without softeners.
• Need for full basket or dedicated hardware capacity instead of forcing a choke.

Double-wrap (and multi-wrap) choke — conceptual awareness

A double-wrap choker (extra full wrap around the load before choking) improves grip and load control on slick or nested bundles. It does not automatically double capacity. Some manufacturers publish higher choke ratings for double-wrap configurations; others do not. Level I rule:

1. Prefer the tag/chart for that product and hitch variant.
2. Do not invent “two wraps = 2× WLL.”
3. Extra wraps still need edge protection, fair lead, and inspection.

Worked example — choker from vertical

Given: Wire rope sling vertical WLL = 8,000 lb. Exam factor for choker = 75%. Load = 5,500 lb in a single choker.

Step 1: Choker capacity = 0.75 × 8,000 = 6,000 lb.
Step 2: 5,500 ≤ 6,000 → acceptable on capacity alone.
Step 3: If load were 6,500 lb, 6,500 > 6,000 → reject that choke plan; change hitch, add legs/slings per plan, or use a higher-rated sling.

Worked example — 80% manufacturer tag

Given: Tag lists vertical 10,000 lb, choker 8,000 lb (exactly 80%). Load 7,500 lb choked.

7,500 ≤ 8,000 → OK to the tag.
If someone wrongly used 75%: 0.75 × 10,000 = 7,500 → still OK, but the tag number 8,000 is what governs when printed. If the tag said 7,000 lb choke, you would stop at 7,000 regardless of the 75% rule of thumb.

Basket Hitch — About 200% When Legs Are Vertical

A basket hitch cradles the load so two parts of the sling support the weight. When both legs of the basket run essentially vertical and share load equally, capacity is often taken as twice the vertical rating (≈200%). That is the classic training relationship.

Conceptual diagram (true vertical-leg basket)

          Hook
         /    \
        /      \   ← two nearly vertical supporting parts
       /        \
   [==== LOAD ====]

Critical conditions for the ~200% idea

• Legs are close to vertical (angle effects handled in §10.2–10.3).
• Load is balanced so each part takes roughly half the weight (known CG).
• Sling is not twisted; contact points are protected.
• The configuration is a true basket, not a choked eye disguised as a basket.

When basket is appropriate

• Loads with two stable support points or a shape that seats in the cradle.
• Need for higher capacity from the same sling body than a single vertical or choke.
• Stable packages that will not slip out the open ends of the basket (use stoppers, wraps, or a different hitch if they will).

When “basket” is a trap

Worked example — basket conversion

Given: Vertical WLL = 5,000 lb. True vertical-leg basket, equal share.

Basket capacity ≈ 2 × 5,000 = 10,000 lb.
Load 9,000 lb → OK on hitch capacity (if angles remain vertical and CG centered).
Same sling choked at 75%: 0.75 × 5,000 = 3,750 lb → 9,000 lb choke would be grossly overloaded.

Worked example — comparing all three hitches

Sling vertical WLL = 6,000 lb (use 75% choke, 200% vertical basket):

A 5,000 lb load: vertical OK, choker not OK, basket OK (geometry permitting). Memorize this three-way comparison—it appears constantly in execution problems.

Putting Hitches Into Field Language

Think in this order every time:

1. What hitch does the plan actually create? (vertical / choke / basket)
2. What does the tag say for that hitch?
3. If only vertical is printed, apply standard relationships only as trained and still respect manufacturer instructions.
4. Does CG and contact geometry keep load share equal?
5. Are angles vertical, or do I need angle factors (next sections)?

Exam-Focused Summary of Hitch Selection

• Vertical = baseline 100%.
• Choker ≈ 75–80% (often 75% on written problems).
• Basket with vertical legs ≈ 200%.
• Double-wrap choke = better control, not automatic double capacity.
• Tag hitch ratings override rules of thumb.
• Misnaming the hitch is how people apply the wrong percentage and fail both the lift and the exam.

Master hitch identity first. Section 10.2 multiplies tension when legs leave vertical; Section 10.3 combines hitch factors with angle math on full problems.