Wikiposts
Search
The Pacific: General Aviation & Questions The place for students, instructors and charter guys in Oz, NZ and the rest of Oceania.

ATPL MET and RVR

Thread Tools
 
Search this Thread
 
Old 30th May 2011, 07:07
  #1 (permalink)  
Thread Starter
 
Join Date: Jul 2007
Location: Perth
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
ATPL MET and RVR

Question in a sample paper:

The visibility at an aerodrome is reported as 900 RVR. As you pass vertically above this airfield at 3000 ft you can clearly see the runway below. You make an ILS approach using standard three degree glide slope.

The distance from the threshold should you expect to first sight the runway is:

a) 1 nm (300 ft on final)
b) 3/4 nm (250 ft on final)
c) 1/2 (180 ft on final)
d) 1/4 (120 ft on final)

Just wondering how to work this out.
Cheers
cloudhigh is offline  
Old 30th May 2011, 07:28
  #2 (permalink)  
 
Join Date: Aug 2006
Posts: 171
Likes: 0
Received 0 Likes on 0 Posts
Cloudhigh,

I saw that one too. I dont get it. I recently sat ATPL Met and got 81%, I didnt get any questions like this on RVR- they were more like how is it presented in a forecast etc.

N
PPRuNeUser0163 is offline  
Old 30th May 2011, 07:34
  #3 (permalink)  
Thread Starter
 
Join Date: Jul 2007
Location: Perth
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
Hey thanks bud.
I'm just worried about not knowing how to solve this question.
I've googled, looked in books and the AIP but of course nothing...

I'm sure one of two things will happen
  • Some one is going to show how easy it is to solve it
  • Someone is going to give a complex answer
cloudhigh is offline  
Old 30th May 2011, 07:43
  #4 (permalink)  
 
Join Date: Sep 2010
Location: location loaction
Posts: 221
Likes: 0
Received 0 Likes on 0 Posts
Cloudhigh I'd say figure out what 900mtrs is in NM and choose that answer. It sounds like they're trying to throw the "standard 3deg slope into confuse you".

I think it's the answer is c)1/2mile and 180ft on final.

Hope this helps

Rocket
rocket66 is offline  
Old 30th May 2011, 07:45
  #5 (permalink)  
JCJ
 
Join Date: Aug 2008
Location: On track
Age: 52
Posts: 44
Likes: 0
Received 0 Likes on 0 Posts
Didn't see anything like this with my exam.

I would guess C, given 3000ft is 1/2nm.
JCJ is offline  
Old 30th May 2011, 07:54
  #6 (permalink)  
Thread Starter
 
Join Date: Jul 2007
Location: Perth
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
Hey thanks guys.
Yeah I was thinking this 3 degree slope had something to do with it but it does make sense.

Appreciated!
cloudhigh is offline  
Old 30th May 2011, 08:04
  #7 (permalink)  
 
Join Date: Mar 2006
Location: Melbourne
Posts: 73
Likes: 0
Received 0 Likes on 0 Posts
I think what they are asking for is a little pythagoras...

This is my take on it -

1/2nm is approximately 925meters
180ft is approximately 55meters

Plug that into - a^2+b^2=c^2

855,625+3,025=858,650

Sqrt 858,650 = 926 or approx 900 meters

Answer (c)



So by taking the distance we are away from the runway and how high we are the hypotenuse should equal the RVR.... I think, I am completely guessing so don't blame me when you're wrong...
hogespa28 is offline  
Old 30th May 2011, 08:15
  #8 (permalink)  
 
Join Date: Apr 2007
Location: AUS
Posts: 26
Likes: 0
Received 0 Likes on 0 Posts
The bloke at the end of the runway can see 900M down the strip which is roughly 1/2 Nm. With 1/2 nm vis on the ground, you would hope that you have the same going back the other way. So they are trying to get to Answer C.
However its a typical question where there are many factors left out and so you just have to pick the best answer to a poor question
Jetpipe2 is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.