PPRuNe Forums - View Single Post - HWC/TWC in Pattern
View Single Post
Old 9th Dec 2021, 17:20
  #6 (permalink)  
+TSRA
 
Join Date: Nov 2007
Location: Wherever I go, there I am
Age: 42
Posts: 740
Likes: 0
Received 0 Likes on 0 Posts
If it is any help, for a Cessna 150 the headwind component is (Cosine of the angle of the wind off your heading) x (the wind speed).

eg 45 degrees off = .7 x wind speed: 90 off = 0: on the nose = wind speed.

I'm sure you can adapt that to an A320?
The funny thing is, the math doesn't change and the airplane doesn't care. Cosine of the wind angle x wind speed works every time, no adaptation necessary. The only difference is that in something like a 320, you've got much less time to figure it out than a single-engine Cessna. Operationally, you've got to find a quicker way to figure it all out that is not formula-based - you don't have time to plug in the variables doing 200 to 250 knots. So, use the cosine method described above, and even if you just remember a few of the values as a function of speed you're fine. I've committed every 20 degrees to memory and then add or take off a bit as necessary. It works well enough:
  • 5-degree crosswind equals 99% of the wind speed
  • 25-degree crosswind equals 90% of the wind speed
  • 45-degree crosswind equals 70% of the wind speed
  • 65-degree crosswind equals 44% of the wind speed
  • 85-degree crosswind equals 87% of the wind speed

Last edited by +TSRA; 9th Dec 2021 at 17:20. Reason: Removed a spurious bullet point
+TSRA is offline