Welcome Guest. Sign in or Signup

For the approach chart,the approach speed category have cat A B C D ,and I know that speed is base on 1.3 Vs0 at the ,maximum certificated landing weight,but why is 1.3 Vs0 not 1.4 or 1.5?

1 Answers



  1. Kris Kortokrax on Feb 23, 2015

    It was an arbitrary choice, giving some margin above stalling speed without using too high a number. Vref is the reference landing speed and in the absence of a published number from the manufacturer is calculated at 1.3 Vso. 14 CFR 23.73 states that Vref cannot be less than 1.3 Vs0.

    Note that if you fly the approach at a higher speed, you must use the minima for the appropriate category.

    0 Votes Thumb up 0 Votes Thumb down 0 Votes


The following terms have been auto-detected the question above and any answers or discussion provided. Click on a term to see its definition from the Dauntless Aviation JargonBuster Glossary.

Answer Question

Our sincere thanks to all who contribute constructively to this forum in answering flight training questions. If you are a flight instructor or represent a flight school / FBO offering flight instruction, you are welcome to include links to your site and related contact information as it pertains to offering local flight instruction in a specific geographic area. Additionally, direct links to FAA and related official government sources of information are welcome. However we thank you for your understanding that links to other sites or text that may be construed as explicit or implicit advertising of other business, sites, or goods/services are not permitted even if such links nominally are relevant to the question asked.