3 ms·

At some point during landing the wing has to stall. Certainly a 3 point landing in a taildragger is taught as an uncontrolled crash from 2 inches above the grou

At some point during landing the wing has to stall. Certainly a 3 point landing in a taildragger is taught as an uncontrolled crash from 2 inches above the ground. The reality is more complex as different parts of the wing will be experiencing different conditions and different wing features (flaps, steps, bugs, dings etc).

zeusk 5y ago
Controlled descent and touch down does not require stall. Not sure where you’re getting that but in my type (sr22), touch down is at speeds considerably above stall speed in landing configuration. Ref Approach (100% flap) -> 85-90kt Stall (100% flap) - 59kt And documented stall speeds are when the wingtips and ailerons start losing effectiveness - the wing still generates plenty of lift.
- krisoft 5y ago
  This might be a different schools of thought then? The way my flight instructor explained to me (Cessna 150) that you can land very smoothly without stalling, but if your airplane has the energy you are still flying. Just you are doing it 0 inches above the runway. If any outside disturbances increase your energy or redirect you (such as a gust of wind, or a bump on the grass field) you become airborne again and the chances of messing things up increases from there. (bunny hopping etc...) So he expected this stall from 4 inches from me, and told me off if he couldn't hear the stall warning whistle come on at the last moment just before touchdown. That being said I also heard that this is absolutely not how one should land an airliner. This type of landing would cause a tail strike there. So who knows. Maybe my trainer was old school. Maybe what is correct on a Cessna 150 on a grass field is not correct on your type or airfield.
  - mannykannot 5y ago
    This may be a matter of loose terminology - in the flare (and when slowing down in level flight generally), once you have reached the angle of attack giving the maximum coefficient of lift, you will descend (and therefore, in the flare, touch down.) Though there will be some flow separation at this point (and before) it is still a couple of degrees from a full-blown stall.
  - avereveard 5y ago
    Stall is about airflow separation, not lift force. You can most definitely not have enough lift for flight, but not at enough angle of attack to be in a stall.
  - jaywalk 5y ago
    The stall warning sounds before the airplane actually stalls, by definition. You were not actually stalling the plane.
- mannykannot 5y ago
  In addition, the ground effect will lower the stalling speed for any given weight and configuration, as compared to at altitude.
NikolaeVarius 5y ago
No it doesn't, Velocity landing should be above stall speed, albeit slightly. No one wants the airframe to crash/slam into the ground. Source: Aeronautical in a previous life
lazide 5y ago
A stall is fundamentally a loss of lift from the airflow leaving a lift producing configuration. Some people might use it as a ‘stall from 2”’ to describe landing, but it’s fundamentally undesirable in controlled flight (which includes getting wheels on the ground). You don’t actually stall at 2”, and if you were that is a very bad idea as a gust of wind can mean you’ll randomly stall at 20ft next time and crash.

zeusk 5y ago

Controlled descent and touch down does not require stall. Not sure where you’re getting that but in my type (sr22), touch down is at speeds considerably above stall speed in landing configuration. Ref Approach (100% flap) -> 85-90kt Stall (100% flap) - 59kt And documented stall speeds are when the wingtips and ailerons start losing effectiveness - the wing still generates plenty of lift.

krisoft 5y ago
This might be a different schools of thought then? The way my flight instructor explained to me (Cessna 150) that you can land very smoothly without stalling, but if your airplane has the energy you are still flying. Just you are doing it 0 inches above the runway. If any outside disturbances increase your energy or redirect you (such as a gust of wind, or a bump on the grass field) you become airborne again and the chances of messing things up increases from there. (bunny hopping etc...) So he expected this stall from 4 inches from me, and told me off if he couldn't hear the stall warning whistle come on at the last moment just before touchdown. That being said I also heard that this is absolutely not how one should land an airliner. This type of landing would cause a tail strike there. So who knows. Maybe my trainer was old school. Maybe what is correct on a Cessna 150 on a grass field is not correct on your type or airfield.
- mannykannot 5y ago
  This may be a matter of loose terminology - in the flare (and when slowing down in level flight generally), once you have reached the angle of attack giving the maximum coefficient of lift, you will descend (and therefore, in the flare, touch down.) Though there will be some flow separation at this point (and before) it is still a couple of degrees from a full-blown stall.
- avereveard 5y ago
  Stall is about airflow separation, not lift force. You can most definitely not have enough lift for flight, but not at enough angle of attack to be in a stall.
- jaywalk 5y ago
  The stall warning sounds before the airplane actually stalls, by definition. You were not actually stalling the plane.
mannykannot 5y ago
In addition, the ground effect will lower the stalling speed for any given weight and configuration, as compared to at altitude.

NikolaeVarius 5y ago

No it doesn't, Velocity landing should be above stall speed, albeit slightly. No one wants the airframe to crash/slam into the ground. Source: Aeronautical in a previous life

lazide 5y ago

A stall is fundamentally a loss of lift from the airflow leaving a lift producing configuration. Some people might use it as a ‘stall from 2”’ to describe landing, but it’s fundamentally undesirable in controlled flight (which includes getting wheels on the ground). You don’t actually stall at 2”, and if you were that is a very bad idea as a gust of wind can mean you’ll randomly stall at 20ft next time and crash.