The Art of Keeping Older Aircraft Flying

As aircraft remain in service for longer, demand for replacement parts, spares and repairs inevitably increases.

For manufacturers, supplying a spare part while the component is still in regular production is relatively straightforward.

The real challenge begins when a component has not been manufactured for many years.

Modern aerospace manufacturing has increasingly focused on high-volume efficiency, automation and repeatability.

Legacy components often require almost the opposite approach.

They may involve:

• very small production quantities
• old engineering drawings and imperial dimensions
• obsolete or difficult-to-source materials
• older casting and forging specifications
• specialist manual manufacturing skills
• interpretation of historic engineering information
• compliance with current quality standards

The capabilities required to manufacture ten obsolete components can therefore be very different from those needed to manufacture thousands of current-production parts.

One of the most important issues is knowledge.

At Ronaldsway Aircraft Company, new apprentices were taught how to read engineering drawings using imperial dimensions and how to manufacture components from older, potentially less consistent castings.

Those skills mattered because legacy aerospace production often involves components designed decades ago but which must still meet modern aerospace quality requirements.

There is also a wider lesson here.

The same core skills required to manufacture obsolete aerospace components are often valuable when developing prototypes or producing early-stage components for new aircraft and defence programmes.

Maintaining these capabilities is therefore not simply about supporting old products.

It helps preserve the broader engineering flexibility required for future innovation.

The operational challenge is equally important.

Producing very small quantities of specialist components can easily disrupt an efficient volume-production environment.

At Ronaldsway Aircraft Company, the solution was to create a dedicated manufacturing cell specifically for this type of work, supported by its own engineering resource.

Separating legacy production from mainstream manufacturing helped protect normal production efficiency while providing the flexibility required to deal with unusual components, historic specifications and small batch sizes.

Material availability can create another significant challenge.

Castings and forgings used historically may no longer be manufactured, while even basic material specifications can change over time.

In some instances, the material specified on an original drawing may simply no longer be commercially available.

An alternative material may therefore need to be purchased in a different condition, heat treated to achieve the required properties and subsequently tested to prove that it conforms with the original specification.

That process adds engineering effort, testing, time and cost long before the actual component is manufactured.

Perhaps the most important issue is how legacy manufacturing is commercially evaluated.

A replacement component that has not been manufactured for ten years cannot reasonably be priced using the same assumptions as a component produced continuously at volume.

The supplier must maintain the people, knowledge, engineering capability, processes and infrastructure required to solve problems that often only emerge once the work begins.

That means legacy aerospace manufacturing should be viewed as a service-level purchase rather than a commodity purchase.

The real value is not simply the component itself.

It is the capability to manufacture that component correctly, safely and compliantly when the original production environment may no longer exist.

The question is not whether the aerospace supply chain can support older aircraft.

Specialist manufacturers can develop the skills, processes and infrastructure required.

The bigger question is whether OEMs and tier-one suppliers recognise that this capability carries a different cost structure from high-volume production.

As aircraft remain operational for longer, the organisations that preserve these specialist manufacturing capabilities will become increasingly important to the resilience of the aerospace supply chain.