When the Legs Give Way & the Trailer Comes Down
The landing gear on a semi-trailer serves a single structural function: it supports the front of the trailer when no tractor is connected. Two retractable legs, operated by a hand crank or power mechanism, extend downward to bear the weight of the trailer nose, the cargo loaded toward the front, and any additional forces imposed during loading and unloading, including the repeated impact of forklifts entering and exiting the trailer. When a landing gear leg collapses, bends, or strips its gears, the front of the trailer drops. If the failure is symmetrical, the nose falls straight down. If one leg fails and the other holds, the trailer tips to one side. Either scenario can crush, trap, or eject a forklift operator working inside the trailer, and can injure dock workers standing in or near the loading area.
Landing gear failures are not rare events. Trailer separation, which includes landing gear collapse alongside trailer creep and premature departure, is among the most severe categories.¹ Loading dock equipment manufacturers have identified landing gear collapse as one of the three primary causes of trailer separation accidents, alongside trailer creep from repeated forklift impact and early departure by the truck driver.² The injuries that result from these failures range from broken bones and crush injuries to fatalities, and the failures are almost always attributable to deferred maintenance, undetected corrosion, or physical damage inflicted during yard operations that no one documented or repaired.
How Landing Gear Works & Why It Fails
Trailer landing gear consists of two telescoping steel legs mounted to the trailer's forward undercarriage, connected by a cross shaft and operated through a gearbox. The gearbox translates the rotational input from the crank handle into vertical movement of the legs, extending them to the ground for support or retracting them for travel. Most landing gear systems use a two-speed mechanism: a high-speed setting for rapid deployment when the legs are not under load, and a low-speed, high-torque setting for the final adjustment under the trailer's weight.³
The gearbox is the most mechanically complex component and the most common point of failure. The internal gears, typically worm gears or bevel gears, are subject to wear from repeated use, contamination from road grit and moisture that infiltrate the housing, and corrosion from exposure to road salt, humidity, and temperature cycling.⁴ As gear teeth wear, they lose their ability to maintain engagement under load. A gearbox that has lost significant tooth profile may hold the trailer's static weight but strip or skip under the dynamic loading imposed when a forklift drives into the trailer, shifting the center of gravity forward and momentarily increasing the force on the landing gear.
Corrosion attacks every component of the landing gear assembly. The legs themselves are steel tubes that corrode from the outside in, losing wall thickness over time. The mounting hardware, things like bolts, rivets, and gussets that attach the landing gear to the trailer's subframe, corrode and weaken, creating the possibility that the entire assembly separates from the trailer rather than simply retracting. The cross shaft that connects the two legs corrodes and can seize, preventing synchronized operation and causing one leg to bear a disproportionate share of the load.⁵
The foot pads at the bottom of each leg, the contact points with the ground, are subject to their own set of failure modes. A missing or deformed foot pad reduces the bearing area, increasing ground pressure and causing the leg to sink into soft surfaces such as asphalt in hot weather or unpaved yard areas. A pad that has been bent or torn away by contact with curbs, yard obstacles, or the ground itself during dragging events leaves the raw end of the leg tube in contact with the ground, concentrating forces and accelerating tube deformation.
Yard Operations & Jockey Truck Damage
One of the most significant and least documented causes of landing gear damage is the handling of trailers by jockey trucks, also called yard tractors or spotters, during yard operations at distribution centers, warehouses, and intermodal facilities. Jockey truck operators move dozens or hundreds of trailers per shift, connecting and disconnecting from trailers rapidly to position them at loading docks, staging areas, and parking rows.
The speed and volume of these operations create conditions for landing gear damage. When a jockey truck connects to a trailer whose landing gear has not been fully retracted, the act of pulling the trailer forward can drag the extended legs across the yard surface, bending legs, tearing off foot pads, and damaging the gearbox mechanism. When a jockey truck drops a trailer without ensuring the landing gear is fully extended and properly positioned, the trailer nose can settle onto partially deployed legs, imposing bending loads the legs are not designed to resist.
Jockey truck operators working at speed may not notice (or may not report) contact between the tractor and the landing gear during coupling and uncoupling. A fifth wheel that is slightly misaligned or a coupling event that involves lateral movement can strike the landing gear cross shaft or leg, introducing damage that is not immediately visible but that compromises the component's ability to bear load. Over time, repeated minor impacts accumulate into structural fatigue that manifests as failure under the next significant load.
The damage inflicted during yard operations is compounded by the fact that it is rarely documented. Unlike over-the-road incidents that generate driver vehicle inspection reports, yard moves typically produce no inspection records. The jockey truck operator may not know the landing gear was damaged. The trailer owner may not learn of the damage until the next scheduled maintenance, if maintenance is scheduled at all. The loading facility may not track which jockey truck handled which trailer on which date. The result is a chain of custody gap that makes it difficult to determine who caused the damage and when, but that does not eliminate the liability of the parties who failed to inspect or maintain the equipment.
The Regulatory Framework
The federal inspection and maintenance regulations that apply to trailer landing gear are the same provisions that govern all trailer components. Under 49 C.F.R. § 396.3, every motor carrier and intermodal equipment provider must systematically inspect, repair, and maintain all motor vehicles and intermodal equipment subject to its control, and all parts and accessories must be in safe and proper operating condition at all times.⁶ Landing gear is unambiguously a part that affects safety of operation; it is the structural support that prevents the trailer from collapsing when uncoupled.
Under 49 C.F.R. § 396.7, no motor carrier may operate a commercial motor vehicle that is likely to cause an accident or a breakdown.⁷ A trailer with visibly corroded, bent, or mechanically compromised landing gear that is dropped at a loading dock for forklift operations is a vehicle likely to cause an accident.
Under 49 C.F.R. § 396.13, drivers must conduct a pre-trip inspection before operating a vehicle and must review any driver vehicle inspection report filed by the previous driver.⁸ Landing gear condition, including leg straightness, foot pad presence, crank operation, and visible corrosion, is a pre-trip inspection item. A driver who documents landing gear damage on a DVIR creates a record that triggers the carrier's obligation to repair the defect before the trailer is placed back in service.
Under 49 C.F.R. § 396.17, every commercial motor vehicle must undergo an annual periodic inspection covering, at minimum, the components listed in Appendix A to Part 396.⁹ Landing gear is not itself one of the categories enumerated in Appendix A, but a thorough periodic inspection, together with the general maintenance obligation under § 396.3, should still address the structural integrity and operability of the landing gear, including the condition of the legs, gearbox, crank mechanism, mounting hardware, and foot pads. A trailer that passes an annual inspection with compromised landing gear reflects an inadequate inspection, not a sudden failure.
OSHA regulations add a separate layer of guidance at the loading facility. Under 29 C.F.R. § 1910.178(k)(1), the brakes of highway trucks must be set and wheel chocks placed under the rear wheels to prevent movement while being loaded with powered industrial trucks.¹⁰ OSHA's Technical Information Bulletin on the inspection of suspension-type highway trailers (trailers built with fiberglass-reinforced panel, sheet-and-post, or plate designs) specifically warns employers to examine the front landing gear before loading or unloading with powered industrial trucks, noting that damage to the landing gear could cause it to collapse when the weight of the forklift is added.¹¹ For that category of trailer, a loading facility that fails to inspect landing gear condition before sending a forklift into a dropped trailer has disregarded OSHA's own guidance on the point.
Where Liability Falls
Landing gear failure cases typically involve at least three categories of potentially liable parties, and sometimes more.
The trailer owner bears primary responsibility for the structural condition of the equipment. Under § 396.3, the owner must systematically inspect, repair, and maintain the trailer.¹² Maintenance records are the first discovery target. A trailer owner that cannot produce records of landing gear inspections, lubrication, gearbox service, or component replacements for a trailer that has been in service for a decade or more has not met the regulatory standard. The owner's exposure increases when the failure involved a condition, such as corrosion, gear wear, or bent legs, that develops progressively and would have been detectable through routine inspection.
The motor carrier that dropped the trailer at the dock bears obligations under § 396.7 and § 396.13.¹³ If the driver who dropped the trailer conducted a pre-trip inspection and failed to identify visible landing gear damage, such as corroded legs, missing foot pads, or a crank that required excessive effort to turn, the carrier may be liable for dispatching defective equipment. If the driver identified the damage on a DVIR but the carrier failed to repair it before the trailer was placed at the dock, the carrier's liability is documented in its own inspection records.
The loading facility bears responsibility under OSHA regulations and common law premises liability for the safety of workers on its premises. A facility that allows forklifts to enter dropped trailers without first inspecting the landing gear for visible damage has failed to protect its workers from a known hazard. The OSHA Technical Information Bulletin specifically directs employers to inspect landing gear on suspension-type trailers before loading or unloading with forklifts.¹⁴ A facility that ignores this guidance and suffers a landing gear collapse has been warned by the federal agency responsible for workplace safety and chose not to act.
The loading facility's liability extends to damage caused by its own yard operations. If the facility's jockey trucks damaged the landing gear during yard moves, the facility bears responsibility for the damage its operations caused, particularly if the facility had no inspection protocol for trailers after yard handling, no system for reporting jockey truck contact incidents, and no process for notifying trailer owners of damage observed during yard operations.
What Discovery Should Target
Discovery in a landing gear failure case should capture the trailer's maintenance history, the circumstances of the failure, and the yard operations that preceded it.
Key categories include:
The objective is to establish that the landing gear's failure was the result of a progressive, detectable condition, like corrosion, wear, or prior damage, that the trailer owner, the carrier, or the loading facility had the ability and the obligation to identify and correct before the failure occurred.
Sources
- [1] Rite-Hite Corporation, "Loading Dock Accidents".
- [2] Door Control Services, "Trailer Separation: Dangers and Prevention".
- [3] Motor City Trailer Repair, "How to Prevent Landing Gear Collapse and Stabilizer Failures".
- [4] Id.
- [5] Id.
- [6] 49 C.F.R. § 396.3(a), eCFR, current as of July 2026.
- [7] 49 C.F.R. § 396.7, eCFR, current as of July 2026.
- [8] 49 C.F.R. § 396.13, eCFR, current as of July 2026.
- [9] 49 C.F.R. § 396.17; Appendix A to Part 396, eCFR, current as of July 2026.
- [10] 29 C.F.R. § 1910.178(k)(1), eCFR, current as of July 2026.
- [11] Occupational Safety and Health Administration, Technical Information Bulletin, "Inspection of Suspension-Type Highway Trailers Prior to Loading and Unloading with Powered Industrial Trucks," TIB 00-07-31, July 31, 2000.
- [12] 49 C.F.R. § 396.3, eCFR, current as of July 2026.
- [13] 49 C.F.R. § 396.7; 49 C.F.R. § 396.13, eCFR, current as of July 2026.
- [14] Occupational Safety and Health Administration, Technical Information Bulletin, "Inspection of Suspension-Type Highway Trailers Prior to Loading and Unloading with Powered Industrial Trucks," TIB 00-07-31, July 31, 2000.
- [15] 49 C.F.R. § 396.3(b)-(c), eCFR, current as of July 2026.
- [16] 49 C.F.R. § 396.17, eCFR, current as of July 2026.