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cobracommander
11th May 2011, 14:42
Greetings fellow aviators, I'm a low timer(CPL) who is preparing for Airline entrance tests. Stumbled upon a few tricky ones( or perhaps I need some sleep :8 !!) but was unable to get my head around the answers. So could anyone who would like to devote sometime on solving the following be kind enough to post the answers with the steps( or atleast the key steps)? Any help would be much appreciated. Thanks in advance:ok:

Q1) what is the rhumb line track from A (4500N 01000W) to B (4830N 01500W) ?

Q2) You are at A(Equator, 59 E) you travel on a bearing of 225 for 100 NM, find out the coordinates of the new location.

Q3) Calculate Density alt if Pressure alt at an aerodrome of elevation 4000' is 5000'. temperature on ad. id 27deg celscius.

FlightPathOBN
11th May 2011, 18:01
You HAVE a CPL?!?!?! :mad:

Oktas8
12th May 2011, 02:45
1) Best answer - who cares? No-one is going to fly a rhumb line that far. But because it's an interview not real life... Measure it on a (Mercator) chart. If you don't have one, draw a triangle to scale. The horizontal line represents 50° chlong (I won't insult your intelligence by telling you how to convert that to nm), the vertical line represent 3.5 degrees chlat (ditto), and the hypotenuse represents the rhumb line connecting the two. (NB: I'm just a flight instructor, so what would I know right? But that is the correct answer as far I recall.)

2) Measure it on a chart. If you don't have one, draw a triangle to scale with a protractor. But in this case, I think the difference between GC and RL will be negligible, so that cuts out some calculating.

A useful short cut would be to answer "a thousand miles from anywhere useful, and just to the left of the large school of hungry sharks".

3) ISA temperature at pressure altitude 5000' is ____°. OAT being 27°, deviation from ISA is therefore +_____°. Density altitude changes at a rate of 120'/°. Density altitude is therefore +_____ feet compared to pressure altitude. DA is therefore ____ feet.

Now I feel tired (coz of the altitude) and thirsty (coz of the temperature) and the fridge is stuffed (coz of both), so where can I find a cold beer?

Good luck with the interview.
O8