FAA Private Pilot Helicopter (PRH)WeatherHard
A pilot's preflight briefing includes a SIGMET advising of severe icing, severe and extreme turbulence, and widespread dust storms lowering surface visibility below 3 statute miles along the route. Which statement about this SIGMET is correct?
- ASIGMETs are issued on a fixed 6-hour schedule regardless of whether hazardous weather exists
- BSIGMETs apply only to hazards significant for light, single-engine aircraft
- CA SIGMET automatically cancels and replaces any AIRMETs previously issued for the area
- DSIGMETs advise of weather that may be hazardous to all categories of aircraft
Show answer & explanationAnswer & explanation
Correct answer: D. SIGMETs advise of weather that may be hazardous to all categories of aircraft
A SIGMET (Significant Meteorological Information) advises of weather that is potentially hazardous to all aircraft, including large turbine-powered aircraft, unlike an AIRMET which addresses hazards primarily significant to light aircraft and lower-performance operations.
Why the other options are wrong
- A. SIGMETs are unscheduled and issued only when qualifying hazardous conditions actually exist or are expected.
- B. This describes an AIRMET, not a SIGMET; AIRMETs target hazards mainly significant to light aircraft.
- C. SIGMETs and AIRMETs are issued independently for different hazard thresholds; one does not automatically replace the other.
SIGMET (Significant Meteorological Information)
An unscheduled weather advisory warning of hazardous weather significant to the safety of all aircraft, including severe icing, severe/extreme turbulence, dust/sandstorms, and volcanic ash.
- Applies to all aircraft, unlike AIRMETs which target light aircraft hazards
- Covers severe icing not associated with thunderstorms
- Covers severe/extreme turbulence or clear air turbulence (CAT)
- Covers dust storms/sandstorms lowering visibility below 3SM, and volcanic ash
Memory trick: 'SIGMET is SIGnificant for everyone—big planes included'