nav question

[dartagnan]

here a question for qualified pilot (If I remember correctly of this question I have seen in a test):

you fly QDR 300 from XXX, you are instruct: "intercept QDR 250 , when on QDR 250, descent and maintain 4000ft, you are now crossing radial 250"


question 1: what angle of interception do you take?
question 2: when do you start your descent?

[pipertommy]

Hi,would`nt the intercept angle depend how close the nav station xxx you are ie 60degrees close in might be alot or 30degrees far out may take for ever?Only my two pennies worth

[BelArgUSA]

In theory... let's see -
You are tracking QDR 300º... and get that clearance, you...
(1) maintin current altitude/level
(2) turn left to track 160º, (unless given a heading) which is shortest intercept (90º) of the QDR 250º...
(3) when turning right to track the QDR 250º, you descent to 4,000 ft QNH...
xxx
As I said all this is (hmmm!) theory - in practice you would get a heading.
Some of these tests have strange questions - written by people who never fly.

Happy contrails

[H Peacock]

Does

intercept QDR 250 , when on QDR 250

mean you have to track away from the beacon? Can you not also trk a radial inbound??

[BelArgUSA]

QDM and QDRs

Hola HP -
xxx
Well yes, sure, you could track inbound on QDR 250º...
However, tracking inbound would be generally expressed with QDM (here 070º) -
At least that is the way it was, when I studied the subject in the early 1960s.
xxx
The last time I used QDM or QDR fixes in real life was over the Atlantic, when there were still some ocean station vessels (OSVs) in the early 1970s. We occasionally had navigators with us, if not equipped with INS. As far as I recall, they gave us a QDR either with their radar, or their VHF or HF D/F, and would only give QDM if we requested to proceed inbound to the vessel (or even QDL - series of QDM every minute or so).
xxx
These operators were bored to death on their OSVs, happy to talk to anyone about anything with planes in their area.
xxx

Happy contrails