Various embodiments of the present disclosure provide an aircraft engine monitoring system. Generally, the aircraft engine monitoring system includes an engine monitoring device and one or more sensors configured to sense engine parameters of an engine of an aircraft and to generate and send signals representing the sensed engine parameters to the engine monitoring device, which stores them as engine performance data. An external device is communicatively connectable to the engine monitoring device to retrieve the engine performance data if both (1) the engine monitoring device determines that the external device is a trusted device and (2) the external device determines that the engine monitoring device is a trusted device, the engine monitoring device is configured to encrypt and securely transmit some or all of the engine performance data to the external device.