Airbus A220 and Embraer E2 operators are being advised of cycle limit amendments to the high-pressure compressor hub on their Pratt & Whitney engines.
The measure is being taken after corrosion on a front hub was discovered during routine engine overhaul.
"This corrosion, also found beneath the anti-corrosion coating, reduces the low-cycle fatigue capability and can occur even during engine downtime," says a proposed US FAA directive.
It says the engine manufacturer has reduced the certified life of the affected front hub of the high-pressure compressor.
The condition could lead to cracking before the component reaches its life limit, potentially resulting in uncontained release of the hub and possible damage to the powerplant and aircraft.
A220s are fitted with the PW1500G engine while the E2 family is powered by the PW1900G. The proposed directive is open for comment until 15 July.