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Part 91 · Subpart B — Flight rules
14 CFR § 91.155
Basic VFR weather minimums
2 paragraphs changed in the last update
(c) Except as provided in § 91.157, no person may operate an aircraft beneath the ceiling under VFR within the lateral boundaries of controlled airspace designated to the surface for an airport when the ceiling is less than 1,000 feet.
(d) Except as provided in § 91.157, no person may take off or land an aircraft, or enter the traffic pattern of an airport, under VFR, within the lateral boundaries of the surface areas of Class B, Class C, Class D, or Class E airspace designated for an airport—
✎ Checkride: ground vis 3 SM, ceiling 1,000 — the "3 and 1" rule.
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Before · Jul 9
§ 91.155(d)(1)
(1) Unless ground visibility at that airport is at least 3 statute miles;
After · Sep 22 · Changed
§ 91.155(d)(1)
(1) Unless ground visibility at that airport is at least 3 statute miles, as reported by the airport's weather observation;
Illustration of how a change is marked — not an actual rule change.
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KNEEBOARD · ORAL PREP
"When do I need supplemental oxygen?"
— your examiner, probably
regbook's answer
Above 12,500 ft MSL up to 14,000 ft, the required flight crew must use oxygen for any part of the flight over 30 minutes at those altitudes.
Above 14,000 ft, the crew must use it the entire time. Above 15,000 ft, every occupant must be provided with it.
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- night currency§ 61.57(b)Night takeoff and landing experience
- bfr§ 61.56Flight review
- arrow§ 91.203Required documents on board
- 1 2 3 rule§ 91.169IFR alternate requirements
- lost comms§ 91.185IFR two-way radio failure
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(c) Except as provided in § 91.157, no person may operate an aircraft beneath the ceiling under VFR within the lateral boundaries of controlled airspace designated to the surface
Pilot/Controller Glossary
Ceiling
The heights above the earth's surface of the lowest layer of clouds or obscuring phenomena that is reported as "broken," "overcast," or "obscuration," and not classified as "thin" or "partial."
Open in the Glossary ›
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