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Greg2041
24th Sep 2008, 14:04
HELP! I have been reading my MET book and can't understand or work-out
how to solve these 2 questions.

Can a kindly soul try and explain to me how to answer these questions in an easy to understand fashion?

Always grateful

Greg


1 The wind at 1000ft during the day at an inland aerodrome in the UK was 33015kt. Using a rule of thumb, what would you expect the surface wind to have been?

A 35008kt.
B 32010kt.
C 31012kt.
D 30005kt



2 At about 1400Z under clear skies at an inland aerodrome in Kent, the surface wind was observed to be 22025kt. The most likely wind velocity at 2000ft agl would be:

A 26040kt.
B 24035kt.
C 22020kt.
D 23030kt.

markp123
24th Sep 2008, 14:28
for over land and from 2000ft agl to the surface..the general rule is that the wind backs around 30 degrees and reduces by about 50%

so from 1000ft...you would assume its already backed by 15 degrees and the speed is down by 25% so do the same again to get an estimate of it at surface. sooo my guess would be 315 and about 11kts. i'd go for B, but it could be C...awful when you get values inbetween 2 of theres.

for the 2nd one.....go the opposite way..add 30 degrees and 50% of speed.sooo 250/37 kts. again i'd say B.

not the biggest fan of met myself...!!

Nozwaldo
24th Sep 2008, 14:28
This is from memory so apologies if I'm not 100% correct. The surface wind backs and decreases from the wind at 1000' by 10 degrees and 5kts approximately (due to friction) so I would go for B. The 2000' wind veers by 20 degrees and increases by 10 kts compared to the surface wind so I would go for B again. Any corrections to this appreciated.

Noz

flightlevel1985
24th Sep 2008, 16:38
I'd say it was answers B for both questions. As the wind backs and slacks as you descend and veers and increases as you climb (in an ideal world lol...)

Greg2041
25th Sep 2008, 08:54
Thanks Guys. Very much appreciated. Apparently the answers are:

1: C
2: B

Hmmm......

Keygrip
25th Sep 2008, 12:22
A question I can't understand or work out .....

Why are you asking PPL studies on the Professional forum rather than the Private Flying forum? :}

(I know the answers, by the way, no need to reply).