Overview
This lecture explains the concept of Zulu time (UTC), its importance in aviation, how to convert local time to Zulu time, and provides example calculations and tips for reading Zulu time in charts.
Zulu Time and UTC
- Zulu time and Coordinated Universal Time (UTC) are the same and used to prevent confusion across time zones.
- Zulu time is based on the current local time in Greenwich, England, and is not affected by daylight savings.
- Zulu time uses a 24-hour clock system, avoiding AM/PM notation.
Understanding the 24-Hour Clock
- 0000 hours is midnight, progressing to 2359 before resetting to 0000 for a new day.
- Times after noon add 12 to the hour (e.g., 1 PM = 1300 hours).
- Do not use 2400; 0000 is the correct term for midnight.
Converting Local Time to Zulu Time
- During Standard Time (November to mid-March), add 5 hours for Eastern, 6 for Central, 7 for Mountain, and 8 for Pacific Time Zone.
- Arizona and Hawaii do not observe daylight savings; always use standard offsets.
- During Daylight Savings Time, add 4 for Eastern, 5 for Central, 6 for Mountain, and 7 for Pacific.
- Remember: Zulu = Local 24hr time + the appropriate offset.
Example Calculation
- To convert 1 PM Eastern (during daylight savings) to Zulu: 1 PM = 1300; add 4 hours; 1300 + 4 = 1700 Zulu.
- For a 2-hour flight starting at 1700 Zulu, landing time is 1900 Zulu.
Reading Zulu Time in Chart Supplements
- Most chart supplements use Zulu time for tower operating hours.
- A "++" symbol means hours are one hour earlier during daylight savings than shown.
- Example: Tower in Central Time Zone with 1100 to 0200 Zulu hours operates from 6 AM to 9 PM local time year-round.
Key Terms & Definitions
- Zulu Time (Z) — Aviation term for Coordinated Universal Time (UTC), based in Greenwich, England.
- UTC — Coordinated Universal Time, a global time standard not affected by daylight savings.
- 24-Hour Clock — Timekeeping method counting from 0000 (midnight) to 2359 each day.
Action Items / Next Steps
- Review chart supplement legends and practice converting local time to Zulu time using 24-hour notation.
- Prepare for test questions involving time conversion calculations.