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AhaBulb: Stuff Everyone Should Know · ahabulb.com/pilot-class-a-floor

Class A airspace generally begins at what altitude?

18,000 feet MSL, up to and including FL 600.

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  1. 10,000 feet MSL
  2. 14,500 feet MSL
  3. 18,000 feet MSL ✔

Why: The AIM defines Class A as 18,000 feet MSL up to and including FL 600. Flights there are generally under IFR, so VFR weather minimums do not apply.

Huh, didn't know that: At and above 18,000 feet, altitudes are called flight levels, like Flight Level One Niner Zero.

The dad joke
Why did the airplane get sent to its room? Bad altitude.
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References

Answer: 18,000 feet MSL. The AIM defines Class A as 18,000 feet MSL up to and including FL 600. Flights there are generally under IFR, so VFR weather minimums do not apply.

  1. AIM 3-2 Controlled Airspace (Class A) www.faa.gov/air_traffic/publications/atpubs/aim_html/chap3_section_2.html
    from 18,000 feet MSL up to and including FL 600
    Checked 2026-10-07.

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FlyingIn Class G airspace above 1,200 feet AGL but below 10,000 feet MSL, what is the day VFR visibility minimum?FlyingBelow 10,000 feet MSL in Class C, D or E airspace, what VFR cloud clearance applies?FlyingWhich type of ADS-B Out equipment is required in Class A airspace, beginning at 18,000 feet MSL?

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