SPILVE.LV • Aviation abbreviations

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Aviation abbreviations

U
U/S — Unserviceable UA — United UAB — Until advised by UAV — Unmanned aerial vehicles UDF — UHF direction finding stations UFIT — Uncontrolled flight into terrain UFN — Until further notice UHDT — Unable higher due traffic UHF — Ultra high frequency (300 to 3,000 MHz)	UIR — Upper flight information region UL — Upper limits UNA — Unable UNAP — Unable to approve UNL — Unlimited UNLC — Unlicensed UNREL — Unreliable UTA — Upper control area UTC — Coordinated universal time

All times are UTC