Any one-Wind dtift calculation whithout flight computer?
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Any one-Wind dtift calculation whithout flight computer?
I know one method already:
Speed of the plane divide by 60, than take the wind speed and divide it by the previous result.
that is the max drift and from that we will substruct acording to the cos angle.
Now, I heard about another method for calculating that.
Any one familiar with it?
Speed of the plane divide by 60, than take the wind speed and divide it by the previous result.
that is the max drift and from that we will substruct acording to the cos angle.
Now, I heard about another method for calculating that.
Any one familiar with it?
I'll probably get shot down for being so unscientific, but I think Lindberg invented it so blame him...
Assuming that my route is all more or less on the same vector, plan my first bit of the route (at cruising altitude and speed) flying overhead two visible landmarks. Flying from one to the other, take the compass heading, compare to the true track.
Then for the rest of that route (or until I've turned more than about 30° in which case I'll repeat the exercise) take that difference as a fixed difference between magnetic heading and true track.
G
Assuming that my route is all more or less on the same vector, plan my first bit of the route (at cruising altitude and speed) flying overhead two visible landmarks. Flying from one to the other, take the compass heading, compare to the true track.
Then for the rest of that route (or until I've turned more than about 30° in which case I'll repeat the exercise) take that difference as a fixed difference between magnetic heading and true track.
G
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thx for the reply
I was also interested to know about wind effect on my plane were the wind direction/kt are known but before the flight, & without the wheez wheel.
Is there another method other than the mentioned above?
Is there another method other than the mentioned above?
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Startby estimating maximum drift - using CO2's method.
Then use the clock code system. Take the angle between your track and the direction of the wind.
If it's 15 degrees, take a quarter of the max drift
If it's 30 degrees, take a half
If it's 45 degrees, take 3/4
If it's 60 degrees (or more) take the lot.
15 is a quarter of an hour
30 is half an hour, and so on, so it's easy to remember.
Sin 15 = .257 (ie, almost exactly a quarter)
sin 30 = .5 (a half)
sin 45 = .7071 (about 3/4)
Sin 60 (or more) = .866 (or more)
Good enough for single-pilot mental dead reckoning.
Then use the clock code system. Take the angle between your track and the direction of the wind.
If it's 15 degrees, take a quarter of the max drift
If it's 30 degrees, take a half
If it's 45 degrees, take 3/4
If it's 60 degrees (or more) take the lot.
15 is a quarter of an hour
30 is half an hour, and so on, so it's easy to remember.
Sin 15 = .257 (ie, almost exactly a quarter)
sin 30 = .5 (a half)
sin 45 = .7071 (about 3/4)
Sin 60 (or more) = .866 (or more)
Good enough for single-pilot mental dead reckoning.
I have found the clock-code method to be the best so far, but used with a different method of calculating max drift:
Divide the wind velocity by TAS (in NM per min).
ie: 60 kts = 1 NM per min.
90 kts = 1.5 NM per min.
120 kts = 2 NM per min...... and so on.
So, at a TAS of 120 kts and a wind velocity of 15 kts the calculation looks like this:
Max drift = 15/2 = 7.5 degrees.
Then apply the clock-code method.
As taught by RAF CFS (Central Flying School).
Divide the wind velocity by TAS (in NM per min).
ie: 60 kts = 1 NM per min.
90 kts = 1.5 NM per min.
120 kts = 2 NM per min...... and so on.
So, at a TAS of 120 kts and a wind velocity of 15 kts the calculation looks like this:
Max drift = 15/2 = 7.5 degrees.
Then apply the clock-code method.
As taught by RAF CFS (Central Flying School).
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I agree with TR completely but you dont have to get too bogged down in numbers. Depending on what you fly (ie: your TAS) you only have top learn 1 set of figures.
Max Drift (MD) = 60/TAS x wind velocity (WV)
So, if you fly a C206 @ 120kts, your MD will always be 0.5 x WV
(or for me @ 480kts it is always wind velocity 1/8th of the WV)
From there....as detailed above, multiply your MD but the SINE of the wind angle:
Here are some easy to remember SINE numbers: (sames as the clock-code method really)
10deg = 0.1
20deg = 0.3
30deg = 0.5
40deg = 0.6
50deg = 0.7
60deg = 0.8
70deg = 0.9
abv 70 = 1.0
Now you can really bore people at parties!!
Max Drift (MD) = 60/TAS x wind velocity (WV)
So, if you fly a C206 @ 120kts, your MD will always be 0.5 x WV
(or for me @ 480kts it is always wind velocity 1/8th of the WV)
From there....as detailed above, multiply your MD but the SINE of the wind angle:
Here are some easy to remember SINE numbers: (sames as the clock-code method really)
10deg = 0.1
20deg = 0.3
30deg = 0.5
40deg = 0.6
50deg = 0.7
60deg = 0.8
70deg = 0.9
abv 70 = 1.0
Now you can really bore people at parties!!
