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aviator_88
22nd Jul 2011, 19:45
heey guys,

I was wondering what method did you use for intercepting radials or QDM/QDR on IR training.

Lets say you are flying QDR 150 and instructor asks you to intercept and follow QDR 350. What is your method??

Edgington
22nd Jul 2011, 21:05
Fly the track of the required QDR until abeam then intercept at 45 degree angle. Be careful when close to the beacon.

How are you being taught?

CAT3C AUTOLAND
23rd Jul 2011, 10:16
One thing I used to do was try my very best to think about where you are reference to the beacon and which was you are pointing. Its easy to lose that spatial awareness.

Always have a picture in your mind where you are and then take it from there.

aviator_88
23rd Jul 2011, 14:57
wow....well that's really simple. Now, get this. It is called KLM method for interception.

Method is different whether you are looking for inb or outb. track.

DQDR - desired QDR (one that you need to go to)
PQDR - present QDR (one that you are right now)
IA - intercept angle in relation to DQDR
*QDR for NDB, radials for VOR

the rule:

if DQDR-PQDR > 90 then a/c track same as DQDR until DQDR-PQDR=90 (abeam)
if/when DQDR-PQDR < 90 but >20 then a/c track IA= 60 until DQDR-PQDR=20
if/when DQDR-PQDR < 20 then a/c track IA= 30 until closing to DQDR

there is a lot of calculations and you need to apply corrections for adf needle if there is strong wind. This method is hard to learn but once you master it you won't lose spatial awareness easily...and it gets more complicated with QDM/inb.courses

Anyway, I am asking this because I don't know whether to use it on sim assessment or not. I wouldn't like some chief pilot or whoever asking me; whaaat the hell are you doooin' boy?!!

rmcb
23rd Jul 2011, 17:12
Assuming no airspace restriction and enough distance to station, I would turn right onto 310°M, intercept QDR170 (QDM350) and perform a relaxed overflight.

I found throughout IR training there was way too much mental maths for my pea brain.

Your DGI, RBI, RMI, OBI gives you your spatial information and what you should do with it all visually.

The techniques (described far better than I could demonstrate) for interpreting, resolving and executing this intercept are best covered with RANT and 'Never Get Lost' by Willem Thaller.

Oddsoft Ltd (http://www.oddsoft.com)
http://www.nevergetlost.at

I am not related in any way to OddSoft or WT but I turned to them hoping there was an easier way. I cannot rate these products highly enough.

FlyingStone
25th Jul 2011, 19:42
there is a lot of calculations and you need to apply corrections for adf needle if there is strong wind. This method is hard to learn but once you master it you won't lose spatial awareness easily...and it gets more complicated with QDM/inb.courses.

It's not that complicated, if you know how to read/interpret instruments properly, know where you are and where do you want to go. Besides, I hope you aren't making it complicated by calculating everything in your head - that's what the "compass rose" on the VOR indicator, HSI, RBI/RMI is for. Personally, I find it much easier with ADF (or VOR if you have RMI), since you have a direct presentation of current radial (or QDR/QDM), so you can track it all the way to radial you wish to intercept.

Nick 1
25th Jul 2011, 20:44
Radial - i have - i want - i set ( heading)
Now QDR ( out bound ) same versus , you Are on RAD 210 want 240 ( so right) set 270 ( right).
You Are on 210 ,want 180 ( left) set hd. 150 ( left) always same versus.
QDM is the opposite es 040 want 070 ( right) so hd.LEFT 010
040 (RAD) want 010 (left) so hd. RIGHT 070 .
Hope this is clear.