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00810564 created the topic: ETA
Hello all, Just having difficulties on questions like these, can anyone help me please
1) A to B 25 nm :2 min Late at B. B to C 50 Nm. Recalculate ETA C.
2) ( from the Book page 122 question 5) the flight planned track shown above has been prepared with six minute markers. I the aircraft is 4 mins late at the second marker, how late
will it arrive at B ?
This is all about proportion. If you find your are two minutes behind your flight plan half way down your trip, you're going to lose another two minutes in the second half, so you'll be 4 minutes late at the destination. I know of one dopey pilot who fell for that one. He was due to arrive at the destination just five minutes before last light. He was four minutes late at the halfway point and said "You beauty, I'm going to make it with a minute to spare". He arrived three minutes after last light and hit a wallaby on the strip.
Your second question is the same situation. If you're four minutes late at the second marker, you're losing two minutes per marker. So you will go on losing 2 minutes for every marker on the map.
Thanks Bob! I Just Did the Exam today , Passed with 81%, Unfortunately, i got that question wrong, I had it form Figure 34 given that D1 is 60nm and D2 is 20, i was suppose to arrive at 0145 at c but your were 3 mins late at x. what is the new eta , so i tough that given 60 nm 3 mins, its 1 mins every 20 nm , so i simply said its 0146 , options were 0146,0147,0149 and another. Can you please explain my confusion Thanks.
Hey - the way I looked at this (if you even care to know lol but I guess someone else might) - if you're already 3 mins late and your orig eta was 0145 then it's now 0148, add an additional min for the 20NM and it is 0149.