unport

un- +‎ port

• (General American) IPA^(key): /ʌnˈpoɹt/

unport (third-person singular simple present unports, present participle unporting, simple past and past participle unported)

1. (mechanical engineering, of a liquid such as fuel or oil, intransitive) To flow away from, and, thus, fail to enter, its intake or drain port.
2. (mechanical engineering, transitive) To cause (a liquid such as fuel or oil) to flow away from, and, thus, fail to enter, its intake or drain port.
   • 2002 August 26, National Transportation Safety Board, Crash of Executive Airlines Jetstream 3101, Bear Creek Township, Pennsylvania, May 21, 2000‎, archived from the original on 9 August 2021, Engine Stoppage Scenarios, page 33:

     Further, the apparent difficulties with the left engine could be explained by unporting of whatever fuel remained in the left tank. Conditions would have been conducive to unporting if, for example, the airplane was in a left bank and in a nose-right sideslip following the loss of the right engine, which is consistent with flying straight while attempting to turn to the left, as indicated by the pilot statement "we're trying" when the controller queried if the airplane was in a left turn. Assuming some usable fuel was in the left tank, it is probable that the flight crew's maneuvering after the right engine stoppage may have intermittently unported it, causing the sequential stoppage and restarting of the left engine. The Safety Board notes that the loss of the right engine occurred while the airplane was in relatively level flight and that the left engine stoppage occurred during attempts to maneuver back to the ILS course after the stoppage of the right engine. Further, the final loss of control may have been precipitated by momentary stopping or starting of the left engine when the airplane was at a reduced airspeed. Impact witness marks and airplane damage were consistent with a loss of control at low altitude.