The Airbus A350-1000 is longer and heavier than the A350-900, and one of the easiest ways to tell the two apart on the ground is underneath the wing. The A350-900 uses four-wheel main landing-gear bogies, while the A350-1000 uses six-wheel bogies with three axles on each side. Airbus introduced the larger gear because the -1000 carries more mass and needs to distribute that weight and braking energy across more wheels while remaining compatible with airport pavement limits. Airbus also redesigned the A350-1000 wing trailing edge and fitted more powerful Rolls-Royce Trent XWB-97 engines as part of the larger variant’s overall performance package.[1][2]
The short answer
The six-wheel main gear spreads aircraft weight over twelve main tyres rather than eight, reduces the load carried by each tyre, provides more braking capacity and helps keep pavement loading within practical airport limits. It also supports the A350-1000’s higher maximum takeoff weight without requiring tyres or wheels to become excessively large.
Why the A350-1000 needed different gear
The A350-1000 was designed to carry more passengers and payload than the A350-900 over long-haul routes. A longer fuselage, higher certified weights and more powerful engines increase the loads the landing gear must handle during taxi, takeoff, landing and braking.
The main gear carries most of the aircraft mass
The nose gear supports only a smaller share of the aircraft’s weight. The main landing gear sits close to the centre of gravity and carries the overwhelming majority. That makes main-gear tyre count, wheel load and brake capacity critical to heavy-aircraft design.
Why not just fit larger tyres?
Larger tyres can carry more load, but tyre diameter and width are constrained by landing-gear bay volume, aerodynamic drag, brake dimensions and structural packaging. Increasing wheel count can distribute mass more efficiently without requiring a dramatic increase in individual tyre size.
Three axles per bogie
Each A350-1000 main bogie carries three axles, each with two wheels. That gives six wheels per main gear and twelve main wheels overall, plus the twin nose wheels. The architecture resembles the six-wheel bogie concept used on several very heavy long-haul aircraft, though the detailed structure and systems are unique to the A350.
Pavement loading
Airport pavement is not stressed only by total aircraft weight. The load is transferred through individual tyre contact patches and axle groups. Wheel load, tyre pressure, axle spacing and landing-gear geometry determine how the stress spreads through concrete, asphalt and supporting layers.
Why more wheels can be kinder to pavement
Spreading a larger aircraft mass across more wheels lowers the average load per tyre and distributes stress over a wider footprint. That does not mean a heavier aircraft automatically creates less pavement stress, but multi-wheel gear helps make high weights compatible with existing airport infrastructure.
Airport compatibility matters at design stage
A long-haul airliner has little commercial value if it can operate only from a handful of specially reinforced airports. Airbus therefore designs landing-gear geometry alongside aerodynamics and structure so the aircraft can use the global airports expected for its mission.
Braking energy
Landing gear does more than hold the aircraft up. The wheel brakes must convert enormous kinetic energy into heat during landing and, in the most demanding case, a high-speed rejected takeoff. More braked wheels allow that energy to be distributed among more brake assemblies.
Kinetic energy rises with speed squared
Kinetic energy is proportional to mass and to the square of velocity. A small increase in takeoff decision speed can therefore increase required brake energy significantly. Higher aircraft weight also raises the total energy that must be absorbed in a stop.
Carbon brakes
Modern widebodies use high-energy carbon brake systems because carbon brake stacks can operate at very high temperatures while offering favourable mass compared with older steel designs. Multiple rotating and stationary discs are squeezed together hydraulically to create friction.
Why brake temperature is monitored
After landing, brakes may remain hot for a significant period. The aircraft can monitor brake temperature so crews and maintenance teams know whether the brakes have enough thermal margin for another departure, where a rejected takeoff could demand very high energy absorption.
Autobrake
Autobrake systems command a target deceleration rather than applying one fixed brake pressure. The aircraft modulates braking based on actual deceleration, available runway friction and other factors. Ground spoilers and reverse thrust contribute to the overall stopping process.
Ground spoilers make the wheels work harder in a useful way
Immediately after touchdown, the wing still produces lift. Ground spoilers rapidly reduce that lift and transfer more aircraft weight onto the landing gear. More normal force at the tyres increases the friction force that can be generated between tyre and runway.
Anti-skid
Wheel-speed sensors and brake-control systems monitor how close each tyre is to excessive slip. Brake pressure is reduced when necessary to avoid sustained wheel lock. The principle resembles anti-lock braking in a road vehicle, but with far higher energy and aircraft-specific control logic.
Why the bogie pivots
A three-axle bogie is long. It must adopt the correct angle for touchdown, taxi and retraction. The bogie beam pivots relative to the main shock strut so the wheel set can align with the runway and fit into the landing-gear bay when retracted.
Progressive touchdown
Depending on aircraft pitch, runway slope and bogie attitude, not all three axles necessarily contact the runway at the exact same instant. Progressive contact helps distribute the transient loads as the strut compresses and the aircraft settles onto the gear.
Oleo-pneumatic shock absorption
Like other large transport aircraft, the A350 uses shock-strut technology that combines compressed gas and hydraulic fluid. Gas acts as a spring while hydraulic metering dissipates landing energy. The tyres also deform and absorb part of the initial impact.
Why the gear must be strong but light
Landing gear experiences some of the aircraft’s highest concentrated loads, yet every kilogram of gear is carried through the entire flight. Designers therefore use high-strength materials and carefully optimised geometry rather than simply adding metal until the structure feels robust.
Titanium and high-strength steel
Large landing gears commonly combine high-strength steels, titanium and aluminium alloys according to load, wear and corrosion requirements. Sliding shock-strut surfaces need extremely durable finishes, while axles and truck beams must tolerate repeated fatigue cycles.
Corrosion control
Landing gear operates in rain, de-icing chemicals, runway contamination and hydraulic-fluid environments. Surface coatings, sealants, lubrication and scheduled inspections protect high-strength components because small corrosion pits can become fatigue initiation sites.
Why wheel changes are routine
Tyres and brake components wear much faster than the main gear structure. Wheel-and-tyre assemblies are therefore designed for comparatively rapid replacement, allowing airlines to change consumable components without removing the entire landing gear.
Aircraft tyres operate at high pressure
High inflation pressure lets a compact tyre carry a very large load. Exact pressure is specific to tyre and aircraft installation. Large transport-aircraft braked-wheel tyres also use dry nitrogen or another approved inert gas under relevant certification rules to limit oxygen content and reduce hot-wheel fire risk.
Tyres are stationary before touchdown
The A350’s wheels are not powered to runway speed before landing. Friction spins them up when the tyres contact the runway, creating the brief smoke often visible at touchdown. The tyre is designed for that event; adding wheel pre-spin motors would impose weight and complexity for limited benefit.
Turning a six-wheel bogie
During a tight taxi turn, each axle follows a slightly different radius. Tyres therefore experience lateral scrub. Ground manoeuvring limits and landing-gear geometry keep those forces within acceptable levels.
Main-gear steering
Some very large aircraft use forms of main-gear steering to reduce tyre scrub and turning radius. The detailed A350 steering architecture is aircraft-specific and should be described from approved Airbus documentation rather than assumed from other widebody types.
The nose gear still determines much of the taxi path
Pilots steer the aircraft using nose-wheel steering and rudder as applicable, but the main gear cuts inside the nose path during turns. Airport taxiway design and pilot reference techniques account for the large separation between cockpit, nose gear and main gear.
Why the A350-1000 is not simply an A350-900 stretch
Airbus states that the -1000 combines a longer fuselage with a modified wing trailing edge, new six-wheel main landing gear and Trent XWB-97 engines.[1] These changes address the higher capacity and weight rather than relying on fuselage length alone.
The Trent XWB-97 connection
More thrust allows the larger aircraft to meet takeoff and climb requirements, but higher takeoff mass also means more energy must eventually be handled by the landing gear. Propulsion, wing and gear therefore form part of the same aircraft-level design problem.
The modified wing trailing edge
The A350-1000’s wing changes help optimise lift and performance at its higher mass. The same basic wing family is retained, preserving commonality, but structural and aerodynamic details are adapted for the larger variant.
Commonality with the A350-900
Airbus highlighted 95% common system part numbers between the A350-900 and A350-1000 at certification.[2] That commonality supports airline training and maintenance, while the landing gear is one of the visible areas where the larger variant needs a materially different solution.
Why commonality has limits
A family aircraft is not identical in every component. Higher loads can require stronger structures, larger brakes, different gear, more powerful engines and changed software standards. Commonality is maximised where it makes engineering and economic sense, not forced where loads demand a new design.
Certification testing
The A350-1000 flight-test programme accumulated more than 1,600 flight hours before certification, according to Airbus.[2] Landing-gear, braking and aircraft-system performance are substantiated through ground and flight testing alongside structural analysis.
Rejected takeoff testing
Transport-category brake systems must demonstrate capability under demanding rejected-takeoff conditions. The test represents an extreme case where a heavy aircraft accelerates to high speed and then stops using brakes that begin from defined conditions without relying on normal reverse-thrust credit.
Why brake fuse plugs exist
Wheels can incorporate thermal fuse plugs that release tyre pressure if the wheel becomes excessively hot. Controlled deflation reduces the risk of a highly pressurised tyre failing violently as brake heat soaks into the wheel assembly.
Gear retraction
After takeoff, the entire six-wheel bogie has to fit into a tightly constrained bay while avoiding fuel tanks, structural members and systems. Retraction geometry controls truck angle and sequence so the long bogie clears doors and surrounding structure.
Why gear doors matter aerodynamically
Exposed wheels and struts create enormous drag. Once the gear is retracted, doors restore the smooth lower fuselage and wing-body surface. Door shape and sequencing must balance aerodynamic efficiency with reliable emergency extension.
Alternate extension
Large transport aircraft include means to obtain a landing-gear-down configuration if the normal extension system is unavailable. Exact A350 procedures belong in approved flight-crew documentation and should not be generalised from other Airbus types.
Fatigue life
A landing gear experiences thousands of cycles of takeoff, landing, taxi and towing loads. Components are therefore fatigue-critical and inspected at defined maintenance intervals using non-destructive testing and dimensional checks.
Overhaul
At major maintenance intervals, landing-gear assemblies can be removed and overhauled. Components may be stripped, inspected, measured, replated or replaced according to approved data. This is specialised work performed by qualified maintenance organisations.
Why the gear looks disproportionately large
The wing and engines attract attention, but the landing gear must safely connect an aircraft weighing hundreds of tonnes to a strip of pavement only through small tyre contact patches. Its apparent bulk reflects the concentrated structural and thermal loads it handles.
What the extra axle really achieves
The third axle is not primarily about redundancy. It is about load distribution and braking architecture. All six wheels still belong to one integrated bogie sharing common structure. Losing a tyre is an abnormal event requiring maintenance assessment, not an assumption that five others make it irrelevant.
Why the A350-900 can use four-wheel bogies
The -900 operates at lower certified weights and therefore can meet its tyre, brake and pavement requirements with a smaller four-wheel bogie. Adding another axle would impose unnecessary mass and complexity if the loads do not require it.
Why the A350-1000 cannot simply use the -900 gear
Increasing aircraft weight while keeping the same wheel count would increase individual wheel and tyre load, brake energy and pavement stress. Airbus selected a different bogie architecture to preserve margins rather than over-stressing the smaller system.
The engineering lesson
The six-wheel main gear is a visible reminder that stretching an airliner changes more than cabin length. Higher capacity increases structural weight, fuel, payload, takeoff energy and landing energy. Every part of the aircraft that carries those loads has to be reconsidered.
Conclusion
The Airbus A350-1000 uses six-wheel main landing gear because its higher mass demands more tyre footprint, more brake capacity and a more widely distributed load path than the A350-900 needs. Three axles per bogie spread weight across twelve main tyres and give engineers more braking surface without making individual wheels impractically large. The gear works together with the -1000’s stronger propulsion and modified wing to turn a larger A350 into a practical airport-compatible long-haul aircraft. What looks like “two extra wheels per side” is really a carefully integrated solution to pavement loading, braking energy, structural strength and aircraft growth.
Sources / Technical References
- [1] Airbus, A350-1000 first flight — modified wing, six-wheel main landing gear and Trent XWB-97 — https://www.airbus.com/en/newsroom/press-releases/2016-11-first-a350-1000-becomes-airborne-for-its-maiden-flight
- [2] Airbus, A350-1000 EASA and FAA Type Certification — https://www.airbus.com/en/newsroom/press-releases/2017-11-airbus-a350-1000-receives-easa-and-faa-type-certification
- [3] Airbus, Aircraft Characteristics / A350 airport planning documentation — https://www.aircraft.airbus.com/en/customer-care/fleet-wide-care/airport-operations-and-aircraft-characteristics/aircraft-characteristics
- [4] EASA, CS-25 Large Aeroplanes — landing gear, tyres and brakes requirements — https://www.easa.europa.eu/en/document-library/easy-access-rules/online-publications/easy-access-rules-large-aeroplanes-cs-25
- [5] Pexels, Mark Theunissen, Airbus A350-1000 in flight — free-to-use image — https://www.pexels.com/photo/airbus-a350-1000-flying-in-clear-blue-sky-34724738/
Disclaimer: Cockpit King provides general aviation education and reference information. Landing-gear loads, tyre pressures, brake limits and maintenance requirements are aircraft-specific and must always be verified using current approved Airbus, component-manufacturer, operator and regulatory documentation. This article is not maintenance instruction.
