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Zulu Time
Coordinated Universal Time (UTC), used as the standard time reference in aviation worldwide to eliminate confusion across time zones. All flight plans, METARs, TAFs, and NOTAMs use Zulu time. For example, 1500Z is 3:00 PM UTC.
Related Terms
- 100-Hour InspectionAn FAA-required inspection for aircraft used to carry persons for hire or to give flight instruction for hire. Under 14 CFR 91.409(b), the inspection must be completed within the preceding 100 hours of time in service. An annual inspection also satisfies the 100-hour requirement, but a 100-hour does not satisfy the annual.
- Abbreviated BriefingA Flight Service weather briefing used to update a previous briefing or to request specific missing information. The pilot tells the briefer when and where the earlier briefing was received so only changes and gaps are covered.
- ACS (Airman Certification Standards)The FAA's standards that define the knowledge, risk management, and skill requirements for each pilot certificate or rating. The ACS replaced the older Practical Test Standards (PTS) and is used by examiners during checkrides.
- Actual InstrumentFlight time logged when the aircraft is operated solely by reference to instruments in actual instrument meteorological conditions (IMC), without a view-limiting device. Actual instrument is distinct from simulated instrument time and is conventionally recorded in a separate logbook column; 14 CFR 61.51(g) governs how instrument time is logged.