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35

The pilot (and the ATC) use the UTC (Coordinated Universal Time). The flight's departure and arrival are in terms of the local times at the respective airports. As for data logging, the FDR/CVR usually records in UTC (preferred) or the relative time count (usually count increments each 4 seconds of system operation). See Appendix M to Part 121 - Airplane ...


32

There are several reasons: For departure clearances. An IFR clearance may have a void or release time so that clearance is only valid between certain times. For holding pattern legs. A standard holding pattern is based on a time of one minute at or below 14,000' MSL and 1.5 minutes above 14,000' MSL on the inbound leg. For holding pattern clearances. ...


32

"Zero seven five seven" is the correct way to state the time, pronouncing each digit separately per the table below. Aircraft call signs are sometimes grouped instead of annunciating each digit, for example United 6330 would be "sixty three thirty" instead of "six three three zero". Otherwise, headings, time, coordinates, and all other numbers used in ...


31

Zulu means the letter Z in radio communication. The letter Z designates UTC time. There is actually a list of time zones for each letter of the alphabet (except J): Alpha time zone: UTC + 1 Bravo time zone: UTC + 2 ... India time zone: UTC + 9 Kilo time zone: UTC + 10 Lima time zone: UTC + 11 Mike time zone: UTC + 12 November time zone: UTC - 1 ... X-ray ...


28

Aviation always uses UTC time. This is from the FAA's AIM, but other countries do the same for obvious reasons: 4-2-12. Time a. FAA uses Coordinated Universal Time (UTC) for all operations. The word "local" or the time zone equivalent must be used to denote local when local time is given during radio and telephone communications. The term "Zulu"...


24

When transmitting time, only the minutes of the hour are normally required. However, the hour should be included if there is any possibility of confusion. Time checks shall be given to the nearest minute and preceded by the word ‘TIME’. Co- ordinated Universal Time (UTC) is to be used at all times, unless specified. 2400 hours designates midnight, the end of ...


23

ICAO SARPs Annex 2 (Rules of the Air) states: 3.5 Time 3.5.1 Coordinated Universal Time (UTC) shall be used and shall be expressed in hours and minutes and, when required, seconds of the 24-hour day beginning at midnight. 3.5.2 A time check shall be obtained prior to operating a controlled flight and at such other times during the flight ...


22

UTC is in principle the same as GMT. But for accurate applications there is a difference: Saying "GMT" often implies either UTC or UT1 when used within informal or casual contexts. In technical contexts, usage of "GMT" is avoided; the unambiguous terminology "UTC" or "UT1" is preferred. Wikipedia UTC: Is defined by atomic clock with corrections for leap ...


21

Zulu time, as others have pointed out, refers to UTC. We use this time in aviation (and meteorology and surely others) because it is easier and it is standard. It's the same time everywhere on earth. If you are flying along the border between Arizona and New Mexico in the summer and given a hold: Cessna 1234 hold at FIX, right turns, 10 mile legs, ...


14

Each airports timezone is listed in the Airport/Facility Directory. I think the FAA is starting to call these "Chart Supplements" now though. You can search for specific airports here but it looks like the results are in .pdf format. The value you want is circled in red here: EDIT: As far as digital sources, explicit time zone information seems missing from ...


13

Let's take the best case scenario to start with, and assume that the cruise ground speed of the airliner is around 400kts. For our best case, we also assume that the runway is lined up with the flight path and that the airspace is quiet so the plane is cleared "straight in" with no vectoring for separation or holding patterns. Descent: A typical descent ...


11

Does daylight saving time affect local airspace? Yes and No. In aviation Flight plan information, weather, etc. all use Zulu Time (UTC). This provides a single time standard everyone in the world can use, and avoids misunderstandings based on various national rules for "Daylight Saving Time", "Summer Time", etc. The airline / airport / travel agent / etc. ...


11

Zulu time is UTC time. The reason for the name zulu is because there is a hour shift of Zero sometimes denoted with a Z and in the nato alphabet Z is Zulu. Many times a route will cross timezone so to avoid confusion about which timezone a time is in controllers and pilots will use zulu time by default. It also avoids daylight savings issues.


11

In IFR the pilot needs to have a second-accurate time indicator for a variety of maneuvers. For example, the standard holding pattern is 1 minute turns and 1 minute straight legs. Having the number of seconds allows the pilot to fly these maneuvers accurately.


10

Customer facing documents like boarding passes and itineraries typically show local times for ease of use. Just use airport clocks. I would not trust the flying public to compute UTC. It would be chaos. Crew facing documents will usually be set to UTC, or zulu time.


10

GMT (Greenwich Mean Time) is a time zone, observed by the UK and Portugal in winter and by Iceland and a number of African countries. UTC (Coordinated Universal Time) is a time standard, defined by an atomic clock. It is kept synchronous with the solar time by adding (or removing) leap seconds. In the GMT time zone, the time is equal to UTC. Before UTC ...


10

Air Traffic Control uses UTC or Zulu time which is the same, all the time, the whole world over. Local only flights will use local time.


9

As @fooot mentions in the comments it means that the hand must be concentric with the hour and minute hands, it is not a reference between the difference of deadbeat and sweep seconds as many watch brands commonly reference now. This is a regulation that is intended to clarify the difference between a second hand that references the main dial and one that is ...


9

Your question looks like it's more about statistics than anything else. It's a common misconception to think that in a random lottery where event E has X% chance of happening, if there is N draws without any occurence of E, E is more likely to happen. This is completely wrong. If you flip a coin, you have 50% (X) chances of getting heads (E). If you ...


8

When flying under IFR in IMC you have no external visual references, so there are a number of reasons you may need to time something: Some approaches require you to be able to time them. VOR approaches have a table of times from the final approach fix to the missed approach point at a given groundspeed: Since you have no other way to judge distance over the ...


8

The philosophy of fighter cabin pressurization is different from that of the passenger aircraft. In case of airliners, the cabin pressure decreases while the aircraft climbs upto a certain altitude, after which the value is kept constant (usually at 6000 - 8000 ft cabin altitude). In case of combat aircraft, the principle is different. The cockpit pressure ...


8

You have almost solved the problem yourself. The website you linked to does not help you because, for some reason, it assumes Local Mean Time (LMT) to be equal to UTC. For your problem, LMT needs to be for 85° of East longitude. So, ignore that website and let's move on. For every degree of longitude, you calculate 4 minutes of difference from UTC. You have ...


8

I assume that you're a passenger travelling on a flight and you want to know how long the flight will last, from takeoff to landing. First you would need to get the route you're going to fly. Sometimes the published route is available on flight-tracking sites, for example this one. After that, you can plot the route on an aviation chart to get the distance. ...


8

In IFR flight you sometimes need to accurately time seconds for approaches or turns. Early watches did not have a "seconds" hand. Some watches had a small secondary dial for seconds, but because of the small size it was hard to read. The rule was written "sweep-second hand" meaning a seconds hand that swept around the main dial so that a pilot could ...


8

If the NOTAM duration is expected to return to service prior to the End of Validity time, the time is expressed by using a date-time group followed immediately by EST (estimate). Any NOTAM that includes an EST must be canceled or replaced before the NOTAM reaches its End of Validity time. If the NOTAM is not canceled or replaced, it will expire at the end ...


8

"Scheduled departure time" is not a term used in the operational environment. It is a term you will find on the passenger side of things, and means the time at which the aircraft is scheduled to leave the departure gate. There are several different operational terms related to departure time: ETD, Estimated time of departure. The estimated time at ...


7

Crew members each have their own approach to this but in general on the long haul routes, as a pilot you have at least 24h layover, so you can catchup on some sleep, walk outside for a bit (depending on the local time) and then sleep some more so you're fit for the next flight back home. At home you have a couple of days off to recover from the trip. On the ...


6

The scheduled time is the EOBT. Flights that depart within 15 minutes of it are considered on-time. Standard taxi times for each airport are included in the scheduled flight time.


6

Yes it does, some Major international airports, notably SYD, have a curfew in place. Commercial passenger aircraft land between 0600 and 23:00 AEST or face sanctions. This in turn affects patterns in Dubai, Singapore, KL, LAX, DFW etc. This is a "must depart by" issue for some of these. This is a politically motivated rule to appease voters in the flight ...


6

I have at least a partial solution for you. As I mentioned in a previous comment, I have done some work towards this goal in the past. What I did based on your request was to extract some of that code to build an API of airports which includes latitude, longitude, UTC offset and timezone values. Here are examples on the endpoints. For all the data in the ...


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