Landing gear overhaul is not an engine shop visit, but it is not a small event either.

Typically performed around every 8–10 years, depending on the aircraft type and maintenance programme, landing gear overhaul is a major planning item that should not be underestimated.

While it may not attract the same level of attention as an engine shop visit, the cost exposure, spare availability, records impact, and downtime risk can be significant. For narrowbody aircraft alone, landing gear overhaul can easily reach USD 250,000 or more. 

Here are some items you need to consider:

One set, multiple limits

Although the landing gear system is reviewed as a set, each unit may have different limits. The nose landing gear, left-hand main landing gear, and right-hand main landing gear may each have different LLP remaining life, thresholds, and life limits.

This is why planning cannot only look at the landing gear as a single package. Each unit needs to be reviewed individually, especially when the aircraft is being prepared for transition, lease return, or future operation.

Exchange is not always a full set

Landing gear exchange does not always involve a full shipset. In some cases, the exchange may only involve the NLG, LH MLG, RH MLG, or specific assemblies.

This makes configuration, remaining life, and back-to-birth traceability review critical. A mismatch in configuration or incomplete traceability can create downstream issues, especially during technical acceptance, lease return, or records review.

Some limits are aircraft-specific

Certain aircraft variants may also require additional limit review. For example, selected Boeing 777 variants may require flight-length-sensitive threshold review, not only fixed flight cycle, flight hour, or calendar tracking.

This means the planning team needs to understand not only the general overhaul interval, but also the aircraft-specific requirements that may affect timing and work scope.

Minimum Remaining Green Time in lease agreement

Lease agreements may require major parts’ LLPs to meet certain remaining cycle/hours, which need to be considered especially if done near redelivery date.

Spare availability is another key pressure point. Limited spare or exchange unit availability, especially for newer-generation aircraft, can affect planning flexibility. Raw material shortages and geopolitical-related supply chain issues may also add further pressure to turnaround time and cost.

Non-routine items need to be considered

Non-routine items can come from several sources, including pre-shop deferred findings, previous inspection reports, hard landing inspection reports, NDT results, corrosion, wear, cracks, or findings identified during the shop visit itself.

These items can affect both cost and turnaround time. Proper pre-shop review helps reduce surprises and supports better budget planning.

AD/SB incorporation

AD and SB Alerts are generally treated as mandatory considerations due to safety reasons. However, non-alert or economic SBs may require further engineering decision-making.

The decision may depend on cost, expected utilisation, asset strategy, remaining lease term, and whether the aircraft is intended for continued operation, sale, or transition.

Staggering and spare planning

Because landing gear may be exchanged by unit, overhaul planning should also consider spare availability and staggered schedules. This can help minimise downtime, especially when spare units are limited.

Staggering may also support better cash flow and operational planning, provided that the remaining life and aircraft requirements allow it.

MRO slot and facility capability

Early slot booking is important, particularly for aircraft types with limited MRO coverage. Facility capability should also be reviewed before committing to a shop.

In-house plating, repair capability, and dedicated NDT Level 3 support may help reduce subcontracting needs and lead-time risk. These factors can significantly affect turnaround time and overall shop visit predictability.

Records to note after the shop visit

After the shop visit, records closure becomes just as important as the physical work performed. Key documents to review include:

• DFPs for every maintenance task performed

• Release certificates for every newly installed or replacement component

• Non-Incident Statement for replacement components listed in the PMTS

A Non-Incident Statement, often referred to as NIS or NIAS, is a document certifying that an aircraft, engine, or specific part has not been involved in any accident or reportable incident, and has not been subjected to severe stress, excessive heat, or submersion.

These records are critical for traceability, future asset value, and technical acceptance. Missing or incomplete records can create issues long after the shop visit is completed.

About TBM Aviation

Founded in 2019, TBM Aviation has become a trusted partner for quality-assured, customizable aircraft technical solutions in Asia Pacific and beyond.

Backed by a team of technical experts with years of hands-on expertise in the aviation industry, our team is committed to deliver results that meet the diverse needs of operators, lessors, MROs, and other aviation industry players alike.