Aviation and air traffic control terminology · MLC-0104
Aviation and air traffic control terms: U (20)
- UAM, see Urban air mobility (UAM)
- UAP, see Unidentified anomalous phenomena (UAP)
- UAS facility MAP (UASFM)Defined grid squares showing maximum altitudes around airports where the FAA may authorize part 107 sUAS...
- UAS test siteIndependently owned UAS test & research sites, recognized by the FAA.
- UAS traffic management (UTM)The unmanned aircraft traffic management ecosystem that will allow multiple low altitude BVLOS operations and...
- UASFM, see UAS facility MAP (UASFM)
- UHF, see Ultrahigh frequency (UHF)
- Ultrahigh frequency (UHF)The frequency band between 300 and 3,000 MHz. The bank of radio frequencies used for military air/ground...
- Ultralight vehicleA single-occupant aeronautical vehicle operated for sport or recreational purposes which does not require FAA...
- UnableIndicates inability to comply with a specific instruction, request, or clearance.
- UnassociatedA radar target that does not display a data block with flight identification and altitude information.
- Uncontrolled airspaceAirspace in which aircraft are not subject to controlled airspace (Class A, B, C, D, or E) separation...
- Under the hoodIndicates that the pilot is using a hood to restrict visibility outside the cockpit while simulating...
- UnfrozenThe Scheduled Time of Arrival (STA) tags, which are still being rescheduled by the time-based flow management...
- UNICOMA nongovernment communication facility which may provide airport information at certain airports. Locations...
- Unidentified anomalous phenomena (UAP)For aviation reporting purposes, a UAP may be airborne objects or other detected/observed objects that are...
- Unmanned aircraft system (UAS)An unmanned aircraft and its associated elements related to safe operations, which may include control...
- Unmanned aircraft (UA)A device used or intended to be used for flight that has no onboard pilot. This device can be any type of...
- Unpublished routeA route for which no minimum altitude is published or charted for pilot use. It may include a direct route...
- Unreliable (GPS/WAAS)An advisory to pilots indicating the expected level of service of the GPS and/or WAAS may not be available...
- Unserviceable (U/S), see Out of service/unserviceable (U/S)
- UplinkCPDLC message sent from ATC to the flight deck.
- Upwind leg, see Traffic pattern
- Urban air mobility (UAM)A subset of Advanced Air Mobility (AAM), referring to an air transportation system utilizing highly automated...
- UrgencyA condition of being concerned about safety and of requiring timely but not immediate assistance; a potential...
- Urgency [ICAO]A condition concerning the safety of an aircraft or other vehicle, or of person on board or in sight, but...
- USAFIB, see Army Aviation Flight Information Bulletin
- UTM, see UAS traffic management (UTM)
20 of 1,122 terms in Aviation and air traffic control terminology (MLC-0104). Request the full dataset.