If the load has to move across the yard and be placed in different rows, a straddle carrier is usually the most flexible choice. If the yard is a dense, fixed container block, an RTG usually stacks more boxes per square metre. If throughput is low and the budget is tight, a reach stacker may be enough.
The comparison is not about which machine is “better”. It is about which constraint dominates: horizontal travel, stacking density, ground works, throughput or capital. Most terminal layouts already answer half of the question before the equipment is selected.
Straddle carrier vs RTG vs reach stacker
| Item | Straddle carrier | RTG | Reach stacker |
|---|---|---|---|
| Primary job | Lift + horizontal transport + placement | Stack and retrieve in a fixed block | Lift, short travel and stack |
| Typical capacity | 10–500 t (container 30–80 t) | 35–220 t | 30–45 t |
| Stacking | 1-over-1 to 1-over-3 | 1-over-3 to 1-over-5 | 1-over-2 to 1-over-4 |
| Horizontal travel | Yes, part of the machine cycle | Limited to the block; needs a truck | Short travel, often yard-only |
| Yard shape | Flexible, irregular routes | Regular, dense blocks | Flexible, lower density |
| Ground works | Moderate; route-dependent | High; rail or runway beams | Moderate |
| Throughput | High for mixed moves | High for dense stacking | Low to medium |
| Transfer between areas | Easy | Needs a tractor/trailer | Easy but slower |
| Capital structure | Higher per unit; fewer units may suffice | High infrastructure + crane | Lowest entry cost |
| Best fit | Precast, steel, modules, mixed yards | Container terminals, high density | Small yards, low volume |
When a straddle carrier wins
- The load travels. The machine picks, carries and places without a trailer, so one unit replaces a crane plus a tractor.
- The yard is irregular. Routes can bend around buildings, storage rows or site constraints; the machine follows the load.
- The load is not a container. Precast beams, steel coils, tanks, modules and other long or awkward loads need a custom frame and multi-point lifting.
- The machine has to move between areas. A straddle carrier can relocate under its own power; an RTG is tied to its block.
- Ground works are limited. A straddle route usually needs less civil work than a rail-mounted or runway-based RTG.
When an RTG wins
- Density is the priority. A fixed block with 1-over-3 to 1-over-5 stacking uses land more efficiently than a straddle carrier row.
- The yard is regular. Rectangular container blocks with defined truck lanes suit an RTG's span and travel.
- Throughput is concentrated. A small number of RTGs can serve a high-volume block with predictable moves.
- Rail or runway infrastructure is available. The civil works are justified by the volume and the site life.
- The load is standardised. Container-only duty with a known fleet and stacking pattern.
When a reach stacker wins
A reach stacker is often the first machine in a new or low-volume yard: lower entry cost, quick deployment and reasonable stacking. It becomes the wrong choice when the travel distance grows, the load becomes heavier or the yard needs higher density. At that point, the operating cost and the number of moves per hour become the constraint. The dedicated reach stacker comparison works through the cycle and the cost per move in detail.
Decision tree
- Does the load need horizontal transport? If yes, start with a straddle carrier. If no, go to step 2.
- Is the yard a dense, regular container block? If yes, compare RTG and reach stacker. If no, go to step 3.
- Is throughput low and capital limited? A reach stacker may be enough. If volume is growing, compare a straddle carrier for flexibility.
- Is the load non-container or over 80 t? A custom straddle carrier or special frame is usually the right family.
- Check the ground and the route. The best machine on paper can fail if the slab, aisle or portal clearance does not fit.
What changes in the yard
The machine choice is also a layout decision, and layout is usually harder to change than equipment. Each option imposes a different footprint on the yard before the first container is moved.
- Aisles and turning. A straddle carrier travels with the load inside its portal, so the aisle has to be clear along the whole route, including corners and the tail swing of long loads. An RTG works a block and needs a truck lane beneath the gantry rather than a wide travel aisle.
- Ground works. RTG loads concentrate at the legs and along the rail or tyre path; a straddle carrier spreads load across its wheels but travels over far more of the yard. Both need a slab checked against real wheel loads, not average pressure.
- Stacking height. RTGs are built for dense, high stacking. Straddle carriers typically work two high and win on horizontal movement instead. If density is the main constraint, this single point often settles the comparison.
- Traffic separation. A carrier moves through the yard with the load overhead, so pedestrian routes, truck lanes and maintenance areas have to be separated along its path. An RTG keeps the load inside a defined block.
- Utilities and lighting. Reefer racks, light masts, drainage and service trenches all become obstacles on a carrier route and need to be planned around before the machine is ordered.
Many yards end up with both. A common arrangement keeps RTGs on the dense blocks and adds one or two straddle carriers for horizontal moves, precast or awkward loads, which avoids rebuilding the terminal in one step. The types page covers the machine families that fit those mixed roles, and the precast page shows why long loads push the layout decision towards a carrier.
Total cost structure
Do not compare only the purchase price. The five-year cost includes civil works, energy, tyres, maintenance, downtime and the number of moves required. An RTG may look efficient per move but needs a truck for horizontal transport; a straddle carrier may cost more per unit but removes a vehicle from the cycle. A reach stacker may have the lowest entry cost but the highest cost per move at volume.
We do not publish a single price because the configuration drives it. For a fair comparison, define the annual moves, the average travel distance, the stacking height and the ground works each option needs. The cost drivers page breaks the price into its seven blocks.
Comparison FAQ
Can a straddle carrier replace an RTG?
In some yards, yes. If the operation needs horizontal transport and the density requirement is moderate, a straddle carrier can replace a crane-plus-tractor system. In a dense container terminal with high stacking, an RTG usually remains more land-efficient.
Which is better for precast concrete?
A straddle carrier is usually the better fit because the load is long, heavy and often has to move across the yard. An RTG can lift precast in a fixed bay, but it needs a separate transport vehicle for the yard move.
Which machine needs more civil work?
An RTG typically needs more civil work because of its runway or rail system. A straddle carrier needs a route designed for its wheel loads, but the works are usually less extensive.
Can I start with a reach stacker and add a straddle later?
Yes, if the yard layout leaves room for a straddle route and the future volume justifies it. Plan the aisles and ground now so the later machine is not blocked by buildings or drainage.