A detection system configured to detect water in a fan case includes a heater, a monitoring camera, and a computing device. The heater is configured to apply heat to the fan case. Any water within the fan case generates a local transient thermal gradient in response to the applied heat. The monitoring camera is positioned proximate the fan case and configured to acquire a plurality of images of the heated fan case. The computing device is configured to: receive the plurality of images from the monitoring camera and analyze the plurality of images to detect the water in the fan case.