What are the two types of airport observations in the US?
There are four types of weather observations: surface, upper air, radar, and satellite. Surface aviation weather observations (METARs) are a compilation of elements of the current weather at individual ground stations across the United States.
What are the four airport components?
Components of an Airport
- Runway.
- Taxiway.
- Apron.
- Terminal Building.
- Control Tower.
- Hanger.
- Parking.
How is the prevailing visibility measured at an airport?
Prevailing visibility is defined as “the greatest visibility value that is reached within at least half the horizon circle or within at least half of the surface of the aerodrome. The visibility reported in the METAR should be assessed at a height of about 1.5 m above the ground at the observing site.
How do airports measure wind?
Wind direction is always given as a radial measure in degrees stating the direction from which the wind is blowing. Wind speed may be given in either knots (nautical miles per hour) or metres per second depending upon the procedures of the State concerned.
What does CAVOK mean?
cloud and visibility OK
The Visibility, Cloud, and Weather groups are replaced by the term CAVOK (cloud and visibility OK) when the following conditions exist simultaneously: Visibility is 10km or more. No CB or TCU and no cloud below 5000 feet or Minimum Sector Altitude (MSA) (whichever is the greater).
How do you determine flight visibility?
Visibility values are determined by both human observers and the Automated Surface Observing Systems (ASOS). The human observer determines visibility by identifying objects and landmarks at known distances throughout a 360 degree circle around the observation point.
What is considered high wind speed?
Modern scale
| Beaufort number | Description | Wind speed |
|---|---|---|
| 6 | Strong breeze | 39–49 km/h |
| 10.8–13.8 m/s | ||
| 7 | High wind, moderate gale, near gale | 28–33 knots |
| 32–38 mph |
Is METAR wind true or magnetic?
METAR winds are true and ATIS winds are magnetic, except Digital ATIS.
Are TAF times in Zulu?
A “Z” follows the date and time grouping to remind pilots that like other aviation times, the time listed in the TAF is in UTC, or “Zulu” time, not local time.