Welcome Guest. Sign in or Signup

4 Answers

Crosswind Component Calculation

Asked by: 16864 views
General Aviation, Private Pilot

When calculating the crosswind component should the sustained wind or gust wind speed be used?

Example:

Wind Direction: 190

Runway: 22

Wind Speed: 17kts           Xwind: 10kts

Gust Speed: 27kts           Xwind: 15.9kts

In my Cessna 172 with a demonstrated crosswind of 15kts I would be good without considering the gust factor.

Thanks

 

mm

 

Ace Any FAA Written Test!
Actual FAA Questions / Free Lifetime Updates
The best explanations in the business
Fast, efficient study.
Pass Your Checkride With Confidence!
FAA Practical Test prep that reflects actual checkrides.
Any checkride: Airplane, Helicopter, Glider, etc.
Written and maintained by actual pilot examiners and master CFIs.
The World's Most Trusted eLogbook
Be Organized, Current, Professional, and Safe.
Highly customizable - for student pilots through pros.
Free Transition Service for users of other eLogs.
Our sincere thanks to pilots such as yourself who support AskACFI while helping themselves by using the awesome PC, Mac, iPhone/iPad, and Android aviation apps of our sponsors.

4 Answers



  1. Chris Carlson on Jan 28, 2013

    There are two answers to this question.

    The first, and more technical answer, is that the POH has a demonstrated maximum crosswind, not an absolute maximum cross wind. The plane can handle a stronger crosswind, but it is not known, because they never tested it during the pre-airworthiness testing. That being said, these tests were done in brand new airplanes with pilots who are very good at what they do.
    I guess you could think of it on a specific time scale, where if the gust happens to be going during the landing, then you are landing with more than 15kt crosswind, but if the gust isn’t going, you aren’t. But the wind could change at anytime.

    The second answer is a reality answer. The plane isn’t brand new, you and I, are not Cessna test pilots who have literally put our lives on the line for Cessna, and know them inside and out, and the weather predictions aren’t perfect either. Gusty wind makes the airplane rapidly change the aerodynamic forces, and it can be detrimental. The FAA calls it wind shear, and stresses about its dangers. If you are coming down crabbed, on a strong crosswind, and slow, and just during your flare, as you parallel your longitudinal axis on the runway, the gust picks up, will you be ready to go around, or will you get pushed in a way you didn’t expect.

    In short, the plane could probably handle it, but don’t push the airplane to its limits if you don’t have to, and be conservative in your own limits, especially in the early stages.

    0 Votes Thumb up 0 Votes Thumb down 0 Votes



  2. Mark Kolber on Jan 29, 2013

    >>In my Cessna 172 with a demonstrated crosswind of 15kts I would be good without considering the gust factor.<<

    If, in the course of your flare to landing you were hit with a 15.9 KT direct crosswind gust, would you be able to handle it?

    I'm not sure what the purpose of your question is. Depending on what it is, the answer might be different:

    1. As Chris pointed out, the "max demonstrated crosswind component" is not an aircraft limitation, so from a FAR 91.9(a) regulatory standpoint, it doesn't matter which number you use.

    2. If it's about safety and determining your personal limitations and whether you should attempt a landing, think about the question I asked at the beginning of this comment.

    3. If it's about crosswind limitations placed upon a student pilot certificate or a flight school, club or FBO policy, those are the ones to ask. Most I'm familiar with would use the gust factor number since that's the safety consideration. I've also seen crosswind limitations that specifically discuss the gust factor.

    +1 Votes Thumb up 1 Votes Thumb down 0 Votes



  3. Jim F. on Jan 29, 2013

    Looking at it from a safety/practical standpoint, I do my preflight calculation with both the sustained winds and the gust factor. That way I know the sustained x-wind factor, as well as what the x-wind factor would be during a gust. If I’m not comfortable with the worst case, x-wind gust scenario, then I’m not gonna do it.

    As for what you feel comfortable with, you’ll need to practice and push your comfort zone a bit (with an instructor, of course.) Find an airport that will offer you a good x-wind, but you still have an “out” on another runway that will offer a good, straight headwind.

    (Runway 226? Did I miss the memo from the FAA about a new runway naming system? 🙂 )

    -1 Votes Thumb up 0 Votes Thumb down 1 Votes



  4. Tarek on Jan 31, 2013

    how can i make or fill a flight planning by my hand, not to use any help from anywhere, by other word manually?

    0 Votes Thumb up 0 Votes Thumb down 0 Votes


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.