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How dangerous is wake turbulence from an airplane that is following? Isn't it a major hazard especially in high traffic areas?

avemg 5y ago
Depends. Can be very dangerous when near the ground on takeoff or landing. Heavier, slower aircraft make stronger turbulence. You especially don’t want to be a smaller aircraft behind a larger one. The vortices sink so if you’re following an aircraft and you’re at the same or higher altitude then you’re fine. If you’re lower then watch out, you might be on an intercept course.
- mikecsh 5y ago
  > Heavier, slower aircraft make stronger turbulence Is it the weight of aircraft that contributes to the wake turbulence or the physical size? Presumably these usually correlate pretty well but just asking for clarity…
  - stevehawk 5y ago
    weight. the wing (plane) is exerting itself on the air and the heavier the plane the stronger the force.
    - mikecsh 5y ago
      Thanks!
- stevehawk 5y ago
  thanks to the A380 it is also dangerous at cruise. https://www.nbcnews.com/news/world/private-jet-flipped-over-wake-turbulence-airbus-a380-reports-n736861 https://www.nbcnews.com/news/world/private-jet-flipped-over-...
skykooler 5y ago
This is one of the reasons ATC maintains a certain separation between landing aircraft. For larger airliners which produce more turbulence, this separation needs to be greater. As you can see from the video, wake turbulence migrates downwards over time, so after thirty seconds or so it's no longer an issue for other aircraft on the same glideslope.
- webreac 5y ago
  The separation between a heavy flight and a small one is 120s. There are many studies to take into account wind (speed and direction) and to have finer table of spacing (often around 85s) taking into account both aircraft types. Near the runway, there is also a ground effect with reflection of the vortex.
quercusa 5y ago
All aircraft produce wingtip vortices that create wake turbulence in flight. The vortex strength increases when the aircraft is heavier and when it flies slowly. Thus, the term "heavy" (unlike light, medium and large) is included by heavy-class aircraft in radio transmissions around airports during take-off and landing, incorporated into the call sign, to warn other aircraft that they should leave additional separation to avoid this wake turbulence. https://en.wikipedia.org/wiki/Heavy_(aeronautics) https://en.wikipedia.org/wiki/Heavy_(aeronautics)
deleted 5y ago
[deleted]
chris_va 5y ago
I was flipped sideways on short final in a 172 from a 7x7 (can't remember exact plane) that landed ~2 minutes prior on a parallel runway... it happens, though the vortices tend to sink fairly rapidly and are more of a concern for smaller aircraft. This story is fairly interesting: https://www.nbcnews.com/news/world/private-jet-flipped-over-wake-turbulence-airbus-a380-reports-n736861 https://www.nbcnews.com/news/world/private-jet-flipped-over-...
- FabHK 5y ago
  Glad you live to tell the story. Was recovery hard?
  - chris_va 5y ago
    Fortunately, not at all. Was able to correct the orientation quickly, and just added power for a go around (about 100' AGL, so had time... but was very much not expecting it up at that altitude given sink rates for vortices) The tower must have been watching pretty closely because they notified other traffic within about 2 seconds before I called in or gained altitude.
bronco21016 5y ago
It can definitely be very dangerous. A CRJ (50 seat, common commuter plane) can easily be rolled sideways from a 737-900 or larger. Imagine a biz jet or single-engine piston aircraft being caught in something like that.
wmij 5y ago
Wake turbulence was a factor in the crash of AA587 from JFK back in 2001. The FO flying the take off encountered wake turbulence from a 747 that took off just prior and overused the rudder in response to the point it snapped the tail of the jet, an A300. https://en.wikipedia.org/wiki/American_Airlines_Flight_587 https://en.wikipedia.org/wiki/American_Airlines_Flight_587

avemg 5y ago

Depends. Can be very dangerous when near the ground on takeoff or landing. Heavier, slower aircraft make stronger turbulence. You especially don’t want to be a smaller aircraft behind a larger one. The vortices sink so if you’re following an aircraft and you’re at the same or higher altitude then you’re fine. If you’re lower then watch out, you might be on an intercept course.

mikecsh 5y ago
> Heavier, slower aircraft make stronger turbulence Is it the weight of aircraft that contributes to the wake turbulence or the physical size? Presumably these usually correlate pretty well but just asking for clarity…
- stevehawk 5y ago
  weight. the wing (plane) is exerting itself on the air and the heavier the plane the stronger the force.
  - mikecsh 5y ago
    Thanks!
stevehawk 5y ago
thanks to the A380 it is also dangerous at cruise. https://www.nbcnews.com/news/world/private-jet-flipped-over-wake-turbulence-airbus-a380-reports-n736861 https://www.nbcnews.com/news/world/private-jet-flipped-over-...

skykooler 5y ago

This is one of the reasons ATC maintains a certain separation between landing aircraft. For larger airliners which produce more turbulence, this separation needs to be greater. As you can see from the video, wake turbulence migrates downwards over time, so after thirty seconds or so it's no longer an issue for other aircraft on the same glideslope.

webreac 5y ago
The separation between a heavy flight and a small one is 120s. There are many studies to take into account wind (speed and direction) and to have finer table of spacing (often around 85s) taking into account both aircraft types. Near the runway, there is also a ground effect with reflection of the vortex.

quercusa 5y ago

All aircraft produce wingtip vortices that create wake turbulence in flight. The vortex strength increases when the aircraft is heavier and when it flies slowly. Thus, the term "heavy" (unlike light, medium and large) is included by heavy-class aircraft in radio transmissions around airports during take-off and landing, incorporated into the call sign, to warn other aircraft that they should leave additional separation to avoid this wake turbulence. https://en.wikipedia.org/wiki/Heavy_(aeronautics) https://en.wikipedia.org/wiki/Heavy_(aeronautics)

deleted 5y ago

[deleted]

chris_va 5y ago

I was flipped sideways on short final in a 172 from a 7x7 (can't remember exact plane) that landed ~2 minutes prior on a parallel runway... it happens, though the vortices tend to sink fairly rapidly and are more of a concern for smaller aircraft. This story is fairly interesting: https://www.nbcnews.com/news/world/private-jet-flipped-over-wake-turbulence-airbus-a380-reports-n736861 https://www.nbcnews.com/news/world/private-jet-flipped-over-...

FabHK 5y ago
Glad you live to tell the story. Was recovery hard?
- chris_va 5y ago
  Fortunately, not at all. Was able to correct the orientation quickly, and just added power for a go around (about 100' AGL, so had time... but was very much not expecting it up at that altitude given sink rates for vortices) The tower must have been watching pretty closely because they notified other traffic within about 2 seconds before I called in or gained altitude.

bronco21016 5y ago

It can definitely be very dangerous. A CRJ (50 seat, common commuter plane) can easily be rolled sideways from a 737-900 or larger. Imagine a biz jet or single-engine piston aircraft being caught in something like that.

wmij 5y ago

Wake turbulence was a factor in the crash of AA587 from JFK back in 2001. The FO flying the take off encountered wake turbulence from a 747 that took off just prior and overused the rudder in response to the point it snapped the tail of the jet, an A300. https://en.wikipedia.org/wiki/American_Airlines_Flight_587 https://en.wikipedia.org/wiki/American_Airlines_Flight_587