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Below is a question from the IREX Text Book, not on line, that i found the answer confusing. Pg 211 Question 20
Q 20.
TAF YZZZ 121930UTC 1220/1308 2101KT 6000 RA SCT010 FEW008
FM130400 9999 RA FEW015 SCT050
Given that the aerodrome whose TAF is given above has a published alternate minima at 1200 ft ceiling and visibility of 6km.
If your ETA at this aerodrome is 0410, the operational requirements which would apply for that aircraft's arrival would be-
[a] none 60 minutes holding
[c] 20 minutes holding may be carried
[d] fuel to proceed to an alternate must be carried
Answer from the Text Book.
The TAF for YZZZ is forecasting a change at 0400 from conditions which are below the alternate minima to conditions that are above
the alternate minima [i.e. from bad' to 'good']. You need not carry the alternate if you have enough fuel to hold until the OPR is lifted 30 minutes after 0400 [i.e. at 0430]. You do not have to carry the alternate you may carry 20 minutes holding instead.
I had deduced that the answer would have been [a] None, as there aren't any OPR with the main body of the TAF or the FM.
The TAF states SCT 010 (not more than 4/8's cloud below minima) and the FM gets better so i'm not sure why 20mins holding would be required.
If someone could point out what i'm missing or if indeed it is an error in the question, it would be very much appreciated.
SCT010 is 3 to 4 eighths of cloud with a base of 1000ft.
FEW008 is 1 to 2 eighths of cloud with a base of 800ft.
Since they are both below the alternate minimum of 1200ft, that constitutes more than 4 eighths of cloud below the alternate minimum. So an alternate or holding is required.
