There are 3 primary data sources for engine trend data:
Manual Data - collected by the pilot/crew from cockpit instrumentation readings and transferred to trend sheets or input into iECHO GPA, the Jet-Care iPad app, and then forwarded to us via email, fax or internet message.
Electronic Data - downloaded by engineers/pilots in various file types from onboard computers. (Typically Maintenance Data Computers, Engine Electronic Control Computers e.g. MDC, FADEC, EEC, DEEC, etc).
ACARS - real time data transmitted directly from the aircraft by automated systems using various-on-board avionic equipment and via Satcom and HF radio links to ground stations - and onward to Jet-Care.