Afternoon All,

Just preparing to resit Nav again on Friday this week after coming up short last sitting and was hoping to get an explanation on this one please.

BOD Caloundra flying to Alice Springs EOD March 5. Amount of daylight available?

A) 9 Hrs 55 minutes
14 Hrs 34 minutes
C) 12 Hrs 18 minutes
D) 13 Hrs 23 minutes

The answer is apparently B. Using appropriate AIP graphs I can only get to 14 hrs and 04 minutes (30mins shy)

Any Ideas?

Dobbo

You might be missing the 30mins because Caloundra is UTC+10hr and Alice is UTC +9hr30min. Info is in ERSA.

Remember as you fly west the EOD local time is later at destination than the origin. You "gain" some daylight time.

If you flew East the EOD local time is earlier at destination than origin. You "lose" some daylight time.

G'day Dav,

I looked at that and it does make sense to me but I thought when converting LMT/ARC/LST via AIP tables that it takes that into account and it appears to do so and the other factor I considered is daylight savings however QLD and NT don't subscribe.

I could be over thinking too!

Thanks for the input.

Cheers mate.

Ok no worries the 30mins short must be from somewhere else in the calculations.
I have checked the AIP graphs.
Do you get:
YCDR BOD 5th March: 05:32LMT
YBAS EOD 5th March: 18:46LMT

YCDR LMT ARC to UTC is minus 10hr:13min = 19:19UTC or (05:19 AEST TZ)
YBAS LMT ARC to UTC is minus 8hr:53min = 09:53UTC or (19:23 ACST TZ)

19:19UTC to 09:53UTC is 14hr 34min daylight available.

Cheers Dav,

I see where the issue is. You lose the half hour in the UTC to LST conversion. I got the same times as yourself give or take a minute with those AIP graphs.
Moral of the story. Remain in UTC time.

Thanks for your help Dav

Dobbo