True Cow-Se - Jeppesen CR-2 Manual

Fig. 29
' OT£: He
:.III'C 10
me Effcnive True Air Speed oppo:.ite hhtcl..
~enion
to left of T .\S arrow lor all problems involving a nab angk
of 10° or greater. Jn this case, h eadwind or tailwind must be applied
w
Effective T rue .\ir Speed rather than to True Air Speed.
Problems 13
Find an(J
an~lc• ,
uwgnelir /i('{u/ing, ground speed.
Wind
True ;\f:lgnctit
Wind
(True)
,\ it Speed C:ou
r~c Vari;nion Velocity Din·< tion
I.
~ IOkt~ . ~51
()0£
30 k ts.
::!·1
() 0
2. 1()5 kt:.. t:Hl
5°W ~0
kts.
~7() 0
130;\IPH 350 11 0£ 30 ;\I P H :l90
10
FINDING WINDS IN FLIGHT
~Quite
often, after you get upstairs, you find the wind is not
behaving as the weather-guesser said it would. You must hold a
different heading from that originally estimated, in order to make good
your cow·se. and you are crossing check points ahead of or behind
planned limes. You know how fast and where you're going <ground
speed and true course> ... also the heading that's getting you there
{true heading) ... but without accurate wind information you
can't re-
estimate the legs ahead. Hence you need to determine the actual wind
direction and velocity.~
Let's assume the following:
Given: True air speed . . . . . . . . 180 MPH
True course . . . . . . . . . .
175°
True heading . . . . . . . . .
160°
Ground speed . . . . . . . . . 144 MPH
Find:
Actual wind direction and velocity
41