Summary
We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as follows:
There have been several reported incidents of high altitude, dual engine flameout on JT15D-5 engines powered aircraft operating in certain meteorological conditions. Subsequent to the investigation of incidents, review of the engine design has revealed that the Fuel Control Hydro Mechanical Unit (HMU) P3 servo can be exposed to excessive moisture and freezing.
We are proposing this AD to prevent engine flameout, and possible dual- engine flameout events, caused by excessive moisture and freezing in the P3 servo, during certain flight conditions.