open book test

hello folks im trying to take a open book test and the answer to the question i gave was c .

they said the answer was wrong.

im not for sure how to get the answer.


ATC has issued you clearance to "Descend at pilots discretion to cross KAYLA at One-One Thousand (11,000 FT MSL)". You are flying at FL290 (29,000 FT MSL), your aircraft has an approximate groundspeed of 300 nautical miles per hour and your aircraft has a standard descent rate of 2,000 FT per minute.

Approximately how many nautical miles away from KAYLA would be the minimum distance that you should start your "Top of Descent" to cross KAYLA at 11,000 FT MSL and how many minutes will this take?

also i have to be at 250 kts when i arrive at kayla

A: 30 Nautical Miles and 6 Minutes.
B: 45 Nautical Miles and 9 Minutes.
C: 60 Nautical Miles and 12 Minutes.
D: 75 Nautical Miles and 15 Minutes.

how would i calculate the right answer.



Thanks.....Robert

Robert,

I would say b

- need to descend 29000 - 11000 = 18000 ft @ 200fpm = 9 minutes
- 9 minutes @ 300 kts/hr or 5 kts/min = 45 nm ;but since you are required to get to 250 kts at KAYLA you will need a bit further

Don't know for sure if this right but it is how I would answer it. Interested to see others' answers.

Cheers, Dave

I would say B

29000-11000=18000/2000 = 9 minutes
Groundspeed 300/60 = 5 nm per minute - 9 x 5 = 45 nm

regards

steve

thanks so much that was what i was looking for.

answers a lt of questions on what i was doing in the level d.

Thanks.....................Robert