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Technology · In the factory and the shop

Powder metallurgy

Powder metal turbine and compressor discs, contamination, inspection

mature, and the cause of the largest current fleet disruption 2 min read · updated 15 October 2026 · checked 15 October 2026

Two independent sources on every claim.

Why it is here

A contaminated powder batch is why several hundred A320neo family aircraft have been grounded.

At a glance

What it is

Powder metallurgy makes a part by compacting metal powder at high temperature and pressure rather than casting or forging it. For high strength turbine and compressor discs it is the standard method, because it produces a fine, uniform grain structure that casting cannot.

In plain terms

Instead of pouring molten metal into a mould, you start with metal powder, press it into shape and heat it until the particles fuse. The result is stronger and more consistent than a casting, which is why it is used for the parts that spin fastest in the hottest part of an engine.

The method's weakness is that the powder has to be clean. A single non metallic inclusion, trapped inside the finished disc where nothing can see it, becomes a stress concentration. In a part turning at thousands of revolutions a minute at high temperature, that is where a crack starts.

Why it matters on the line

Pratt and Whitney disclosed in 2023 that some powder batches used in the PW1000G family carried contamination. Because the defect is internal and invisible, the only response available was to pull the affected population and inspect it.

On the line

The exposure is the length of the shop visit, not the inspection. At 250 to 300 days, one unplanned removal can take an aircraft out of service for most of a year if no spare engine is available, which makes spare and lease engine access the planning problem rather than inspection scheduling. Confirm engine serial numbers against the affected population rather than assuming by aircraft delivery date. Smaller operators are disproportionately exposed, because an A220 or E2 fleet runs a thinner spare pool than a large A320neo customer.

The industrial consequence runs further than the grounded aircraft. The same capacity that builds new engines also feeds the repair campaign, so Pratt had to choose between new build allocation and supporting customers already grounded. It prioritised the grounded fleet, and Airbus scaled back its A320neo ramp as a direct result.

Where to read more

The affected engine family is covered on the PW1000G geared turbofan page. The aircraft most affected are the A320neo family, the A220 and the E-Jet E2.

Sources