Aircraft Landing Gear: Systems, Components, Overhaul — and Where to Source or Sell Gear Parts

Technical Guides · 10 min read · Published 2026-07-19

Aircraft landing gear is the retractable structural system that supports an aircraft on the ground and absorbs landing loads — comprising the struts (oleo/shock absorbers), wheels, brakes, actuators, uplocks/downlocks, and the hydraulic and electrical systems that extend and retract it. Because gear components are life-limited and overhauled on fixed cycles (typically every 6–10 years or a set number of landings, depending on type), operators continually need serviceable, overhauled, and as-removed gear parts — making landing gear one of the most active, highest-value segments of the aircraft parts aftermarket.

Key Takeaways

Landing gear is life-limited and overhauled on a fixed calendar/cycle schedule — it is not run to failure, which makes aftermarket demand structural and predictable.
The gear system is more than legs and wheels: actuators, uplocks/downlocks, proximity sensors, and brake components are all individually serviceable, high-value part numbers.
Exchange programs exist because a gear overhaul grounds the aircraft — an exchange installs an already-overhauled unit and returns yours as the core.
For life-limited gear parts, back-to-birth traceability plus the FAA 8130-3 / EASA Form 1 release is what makes a used part installable and sellable.
Removed and as-removed gear has real core value — operators holding AR gear can sell it into the overhaul pipeline rather than scrapping it.

What Aircraft Landing Gear Does

Landing gear carries the aircraft on the ground, absorbs the vertical energy of landing, provides steering and braking, and — on retractable designs — folds away in flight to eliminate drag. Configuration-wise, most modern aircraft use tricycle gear (a nose gear plus two or more main gears); older and specialty types use tailwheel arrangements. Light aircraft may have fixed gear; transport-category aircraft are overwhelmingly retractable.

Structurally, each gear assembly is built around a shock strut and carries wheels, brakes, and the mechanisms that extend, retract, and lock it — every element of which is a maintainable, replaceable component with its own part number and service life.

Landing Gear Systems: Extension, Retraction, Locking and Sensing

On retractable aircraft, the gear is a hydro-mechanical system with electrical sensing layered on top:

Hydraulic extension and retraction — actuators driven by the aircraft hydraulic system raise and lower each gear in a defined sequence, with sequencing valves controlling door and gear order.
Uplocks and downlocks — mechanical locks that hold the gear stowed in flight and positively locked down for landing; downlock springs and lock actuators are frequent replacement items.
Emergency/alternate extension — a gravity free-fall or standby system that gets the gear down and locked if the primary system fails.
Position sensing and warning — proximity sensors and switches feed the gear position indication and configuration warnings; sensor and harness faults are a routine source of parts demand.

Main Landing Gear Components

These are the assemblies and part-number families that move through the aftermarket constantly:

Shock strut / oleo — the gas-over-oil absorber that takes the landing loads; seals, glands, and chrome surfaces drive its overhaul cycle.
Wheels and brakes — the highest-turnover gear components; wheel halves, heat packs, and brake units cycle on landings.
Actuators — retract actuators, door actuators, steering actuators, and lock actuators.
Uplocks, downlocks and springs — small parts with outsized AOG impact when they fail inspection.
Proximity sensors and force transducers — position sensing and weight-on-wheels logic.
Drag braces, side braces and torque links — the structural members that locate the gear.
Steering components — steering collars, metering valves, and feedback units on the nose gear.

Examples from our indexed inventory pages: the 747 body main gear retract actuator, 777 nose gear valve assembly, 787 proximity sensor, and 787 brake system control unit.

Overhaul Cycles: Why Landing Gear Demand Never Stops

Landing gear is not run to failure. Airworthiness requirements put gear assemblies on a fixed overhaul schedule — commonly every 6 to 10 years or a defined number of landings, depending on the type. When the calendar or the cycle count runs out, the gear comes off the aircraft regardless of how it looks.

That schedule is what makes the landing-gear aftermarket structurally different from failure-driven parts categories: demand is predictable, recurring, and fleet-wide. Every overhaul event generates both a need (an overhauled or exchange gear set to install) and supply (the removed cores entering the overhaul pipeline). Life-limited parts inside the gear must be tracked back to birth, which is why the paperwork on a gear part is as important as the hardware.

Overhaul vs Exchange: Keeping the Aircraft Flying

In a straight overhaul, your own gear is removed, disassembled, inspected, re-plated and re-sealed as needed, reassembled, tested, and returned — which grounds the aircraft (or requires a spare set) for the turnaround time.

In an exchange, you receive an already-overhauled unit, install it, and return your removed unit as the core. Downtime shrinks from weeks to days. The economics hinge on core condition and trace: a clean core with complete records earns full core credit; missing paperwork erodes it.

Condition codes work the same here as everywhere in the aftermarket — NE / OH / SV / AR — and the release paperwork (FAA Form 8130-3 or EASA Form 1, plus back-to-birth trace for life-limited parts) is non-negotiable for installation. See our guides on verifying an 8130-3 and reading trace documentation.

Landing Gear by Aircraft

Gear architecture and the high-demand part numbers differ sharply by platform. We source gear assemblies and components across:

Beechcraft King Air — the classic 6-year turboprop gear overhaul cycle; actuators, rollers, downlock springs, and retract rods are the recurring items.
Cessna Citation — business-jet gear sets and brake components across the 500/560/680 families.
Learjet — gear and brake support for the legacy fleet.
Boeing 737 / 777 / 787 — actuators, sensors, brake control units, and wheel/brake hardware.
Airbus A320 family — gear components and brake system LRUs.

Send the part number, aircraft type, and effectivity — availability is confirmed per request through our vetted supplier network.

Source, Exchange or Sell Landing Gear Parts

1. Source gear parts. From complete gear assemblies to a single downlock spring — send your part number and condition requirement for a same-day quote with trace paperwork stated up front. Request a quote.

2. Sell your removed gear and cores. AR gear assemblies, actuators, wheels, and brake cores hold real value in the overhaul pipeline. Tell us what you're holding — part number, condition, and available records — for a buyback range.

3. Exchange program. Gear due overhaul but the aircraft needs to fly? An exchange installs an overhauled unit now and cycles your core into the pipeline.

Frequently Asked Questions

How often is aircraft landing gear overhauled?

Landing gear is overhauled on a fixed schedule set by the manufacturer — commonly every 6 to 10 years or at a defined number of landings, depending on aircraft type. It is life-limited, not run-to-failure, which is why serviceable and overhauled gear parts are in constant aftermarket demand.

What is the difference between a landing gear overhaul and an exchange?

In an overhaul, your own gear is removed, disassembled, inspected, and restored to serviceable condition — which grounds the aircraft during turnaround. In an exchange, you receive an already-overhauled unit and return your removed unit as a core, minimizing downtime.

How much does a landing gear overhaul cost?

It varies widely by aircraft type — from thousands of dollars for light-aircraft and turboprop gear to six figures for transport-category gear sets. The total depends on the overhaul scope, parts replaced, whether an exchange is used, and the core value of the removed unit. Request a quote with your aircraft type and part numbers for current exchange and overhaul-support pricing.

What paperwork should come with a used landing gear part?

A traceable used or overhauled landing gear part should include an FAA Form 8130-3 (or EASA Form 1), the removal/teardown documentation, and back-to-birth traceability for any life-limited parts. Verified paperwork is what separates a usable part from unsellable stock.

Can I sell removed or as-removed landing gear?

Yes. As-removed gear assemblies and components are the input stock for the overhaul pipeline, and cores with complete records command real value. Provide the part number, condition, and available trace documentation to get a buyback or consignment range.

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