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PASS flash card question...

w8n4swa

...in OAK!
Joined
Dec 10, 2001
Posts
185
Total Time
11000
Hello anyone with the John Pansmith flash cards,

I've been studying John's Flash Card Study System with all this sitting around time and I have a question. One of the orange tab cards from the FRM asks "What distance per 1000 feet can you expect to cover when at idle and....

320 knots?

280 knots?

250 knots?

Answers:

320 knots: 2 nm/1000 feet.

280 knots: 2.5 nm/1000 feet.

250 knots: 3 nm/1000 feet.


OK, with power at IDLE, we assume a descent and the question appears to be asking the distance covered in 1000 feet of altitude. At any rate of descent the faster speed (320 kts) would cover more distance than the slower speeds. Can anyone explain these answers to me?

In the forest but can't see the trees...
 

R8J

Member
Joined
Nov 27, 2001
Posts
12
Total Time
14000+
The numbers are for the distance from a fix to start your descent. For example:

If you are planning to descend at 280k and have 20,000 feet to loose, (20x2.5) you would start your descent at 50 miles from the fix.

At 320 (20x2.0) you would start you descent at 40 miles out. The /1000' is for the altitude you need to loose.

Hope I didn't turn it to mud
 

w8n4swa

...in OAK!
Joined
Dec 10, 2001
Posts
185
Total Time
11000
R8J,

You didn't muddy the water a bit...in fact you just cleared it for me. I was focusing on the rate of descent being consistent with all speeds...wrong! 320 knots would get us down much faster than 250 kts. Thanks!

Like I said, in the forest but can't see the trees....
 
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