Every crane lift on a real jobsite has a plan written down before the hook goes near the load. That’s a sentence that surprises some people. Most of what the public sees of a crane is a long piece of yellow steel swinging something heavy through the air, and it looks like the operator is making it up as they go.

They’re not.

What a lift plan covers

A lift plan, in its simplest form, answers these questions for one specific lift:

  • How heavy is the load?
  • How far from the crane will it be at its furthest point (the radius)?
  • Can the crane lift that weight at that radius? The load chart says yes or no — it’s not the operator’s opinion.
  • How will the load be rigged? Slings, shackles, chokers — what gear, in what configuration, at what working load limit?
  • Who is signalling, and how (radio, hand signals, both)?
  • What’s the wind limit for this lift, with a stop-work threshold?
  • What’s the ground bearing under the outriggers, for mobile cranes?
  • What does the swing path look like — what’s overhead, what’s underneath, who’s in the way?

For a small commercial lift, this might be a one-page form. For a critical lift — anything heavy, anything over occupied space, anything near power lines — it’s an engineered document, signed by someone with letters after their name.

Who writes it

Depends on the lift and the company. On a tower crane that’s been on a job for months, the routine lifts are covered by the standing crane plan and the operator handles them inside that envelope. A lift outside that envelope — a piece of equipment, an HVAC unit going on the roof, a tilt-up wall panel — gets a one-off lift plan written by the crane company’s coordinator, or by the project’s lift director, or both.

On a mobile crane (the kind that drives in for a day and leaves), the lift plan starts with the rental company and gets reviewed by the operator on arrival. If anything on site is different from what the plan assumed — the ground isn’t where it was said to be, the load weighs more than the spec sheet, the building changed since the site survey — the plan stops being a plan and starts being a conversation.

Load chart math

This is the part of the job non-operators don’t usually think about. Every crane has a load chart that tells you, for a given configuration (boom length, jib, counterweight) and a given radius, how much it can lift. The number drops off fast as radius increases. A crane that picks 50 tonnes at 10 metres might pick 12 tonnes at 25 metres.

Most lift planning is, mechanically, this: weight of the load → confirmed radius → look it up on the chart → leave a comfortable margin. The comfortable margin is what experience buys you. A green operator might run a lift at 90% of chart capacity because the chart says it’ll work. An operator who’s seen things go wrong leaves more room.

What changes on a windy day

Wind is the variable that ends more lifts than any other. Cranes have manufacturer-stated wind limits — sometimes 9 m/s, sometimes 12, sometimes lower for specific load types like big flat panels that catch the wind like a sail. Above that, the lift doesn’t happen, no matter what the schedule says.

A lift plan written on a calm Tuesday assumes calm conditions. By Wednesday, the wind is 15 m/s. The lift doesn’t go. This is the most common reason crane work gets pushed: not equipment failure, not labour, not coordination. Just weather.

A good lift planner builds buffer into the schedule for this. A good operator doesn’t get pressured out of calling a stop when conditions cross the line. Both of those are quieter skills than people give them credit for.

When the plan and reality diverge

Here’s the part nobody puts in a procedure manual: every plan, on every site, has small ways it’s wrong. The load’s actually 5% heavier than the spec sheet said. The radius is half a metre further than planned because the laydown area moved. The wind picks up halfway through the lift.

The job of the operator and the signaller, at that point, is to know what kind of wrong it is. A 5% weight difference at 50% chart capacity is nothing. A 5% difference at 90% chart capacity is something else. An operator who’s earned their hours has internalized the difference and knows when to stop, re-rig, re-plan, or proceed.

That gap between the written plan and the lived lift is where craft lives. It’s also where accidents live, on the days craft loses.

Why this matters to non-operators

If you’re a project owner or a GC and you’re watching a lift, the right question to ask isn’t “are we paying for too much planning?” It’s “is the operator the one who picked up the load, or the one who quoted the lowest?” Those are sometimes the same person. They’re often not.

A careful lift plan is invisible if it works. The cost of skipping it is invisible until it doesn’t.