Intercepting QDM’S and QDR’S (fixed card ADF)
Guest
Posts: n/a
Dragger of Tail:
Perhaps a specific example would help (fixed card):-
EG. to fly along inbound on a bearing 270 from NDB assuming a/c to west of station. Also assuming you have tuned and positively identified station.
1. Turn a/c to mag heading of 090 - the reciprocal of 270 to point to the ndb.
2. observe ADF. The needle will point either left or right unless you happen to have a bearing from the station of 270.
3. turn 45 deg towards needle and fly until the adf needle points 45 deg towards the opposite side of the face of the dial.
You are now bearing 270 from station.
If you turn to 090 and fly that heading in a no wind situation you will track to the station. A cross wind will require bracketing to compensate - a whole other lesson
Draw it on a piece of paper. Imagine the arrow of the adf is attached to the ndb with a long piece of invisible string.
Does that help?
(editing for alcohol induced dyslexia)
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[This message has been edited by Code Blue (edited 26 December 2000).]
[This message has been edited by Code Blue (edited 26 December 2000).]
Perhaps a specific example would help (fixed card):-
EG. to fly along inbound on a bearing 270 from NDB assuming a/c to west of station. Also assuming you have tuned and positively identified station.
1. Turn a/c to mag heading of 090 - the reciprocal of 270 to point to the ndb.
2. observe ADF. The needle will point either left or right unless you happen to have a bearing from the station of 270.
3. turn 45 deg towards needle and fly until the adf needle points 45 deg towards the opposite side of the face of the dial.
You are now bearing 270 from station.
If you turn to 090 and fly that heading in a no wind situation you will track to the station. A cross wind will require bracketing to compensate - a whole other lesson
Draw it on a piece of paper. Imagine the arrow of the adf is attached to the ndb with a long piece of invisible string.
Does that help?
(editing for alcohol induced dyslexia)
------------------
-.-- --.- -..-
[This message has been edited by Code Blue (edited 26 December 2000).]
[This message has been edited by Code Blue (edited 26 December 2000).]
Guest
Posts: n/a
Biccy,
How do you transpose the needle when you are using a strip DI ?. I find the + and - hdg/QDM/R method works in this case, otherwise transposing is a good crosscheck.
I`ve always assumed that the R in QDR referred to reciprocal. Unlikely that it came from radial since they weren`t invented then.
I don`t imagine many atcos will get too confused if you say you`re on a radial from an NDB I think they`re usually aware which beacons on their patch are A1 or A8.
Q code never caused me any grief but I`m a Luddite. Stupid is a stupid word.
How do you transpose the needle when you are using a strip DI ?. I find the + and - hdg/QDM/R method works in this case, otherwise transposing is a good crosscheck.
I`ve always assumed that the R in QDR referred to reciprocal. Unlikely that it came from radial since they weren`t invented then.
I don`t imagine many atcos will get too confused if you say you`re on a radial from an NDB I think they`re usually aware which beacons on their patch are A1 or A8.
Q code never caused me any grief but I`m a Luddite. Stupid is a stupid word.
Guest
Posts: n/a
1) enter NDB ident in SP
2) LS 1L (LEGS page)
3) Execute
or (optional)
4) enter intercept course in SP then LS 6R
5) LNAV
6) order coffee (with a little sugar please)
easy ehhh?
After my CPL exam can't remember doing an intercept anymore. And that's the reason I sleep so well since then.
2) LS 1L (LEGS page)
3) Execute
or (optional)
4) enter intercept course in SP then LS 6R
5) LNAV
6) order coffee (with a little sugar please)
easy ehhh?
After my CPL exam can't remember doing an intercept anymore. And that's the reason I sleep so well since then.
Guest
Posts: n/a
Try this: QDM=required-head-intercept
QDR=tail-required-intercept
Transpose needle to DG ...
To intercept a QDM:
from "required"(QDM) on your DG >>> go past the "head" (needle) >>> to find a suitable "intercept" heading (on that side)
difference between required&head should approx. equal difference between head&intercept ... round up/down to closest 30/45/60/90
Note: obviously when the difference is greater than 90, you are on the wrong side of the station ... thus you have to fly the reciprocal until past the station
To intercept a QDR:
from the "tail"(needle transposed onto your DG) >>> go past the "required" QDR >>> to find a suitable "intercept" heading
Same difference-rule as for QDM
Ignore the fixed card, think numbers later and double-check once you are on your intercept heading
Remember: there is only one way, the head of the needle moves ... DOWN !!! ... where ever you are or go (except of course when you are actually flying a QDM/QDR)
Watch it: I saw guys getting to comfi with this method, actually neglecting their situational awareness !!!
Happy New Year
Cheers and Beers
LetsFetz
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Let there be cold beers on a hot day !!!
QDR=tail-required-intercept
Transpose needle to DG ...
To intercept a QDM:
from "required"(QDM) on your DG >>> go past the "head" (needle) >>> to find a suitable "intercept" heading (on that side)
difference between required&head should approx. equal difference between head&intercept ... round up/down to closest 30/45/60/90
Note: obviously when the difference is greater than 90, you are on the wrong side of the station ... thus you have to fly the reciprocal until past the station
To intercept a QDR:
from the "tail"(needle transposed onto your DG) >>> go past the "required" QDR >>> to find a suitable "intercept" heading
Same difference-rule as for QDM
Ignore the fixed card, think numbers later and double-check once you are on your intercept heading
Remember: there is only one way, the head of the needle moves ... DOWN !!! ... where ever you are or go (except of course when you are actually flying a QDM/QDR)
Watch it: I saw guys getting to comfi with this method, actually neglecting their situational awareness !!!
Happy New Year
Cheers and Beers
LetsFetz
------------------
Let there be cold beers on a hot day !!!
Guest
Posts: n/a
Gary Halliday, I think you may have been addressing me.
I have never flown a civil transport jet with a strip DI as its main heading reference.
Now, when you say "Unlikely that it came from radial since they weren`t invented then" are you perhaps referring to VOR radials?
I think there may be some confusion between the radio theory use of the word "radial" and the common every day and navigation first principles meaning of "radial".
We all know that the radio signal transmitted by a VOR ground station is different in each different direction from the station. This of course is in contrast to the signal being transmitted from an NDB ground station where the signal is the same in all directions, hence the "ND" part of "NDB" standing for "non directional".
So you might suggest that since NDBs transmit the same signal in all directions that on a radio theory level they do not in principle use unique "radials".
But I would advocate a more common sense approach - which also happens to more neatly fit in with navigation first principles. I refer to a popular dictionary,
"RADIAL : like a radius, branching from a common centre"
and
"RADIATE : to emit rays, to spread out as if from a centre"
In a navigation context I could offer a definition of radial such as "an imaginary straight line starting at a defined position and continuing forever in a defined direction". Note that this could refer to an NDB - or a VOR - or any known point on a map. Sometimes this might be called a "position line".
The benefit of using the term "radial" when talking about NDB navigation is that there is no confusion about bearings being TO or FROM, radials always being FROM the ground station.
I do not know what the "R" in "QDR" was originally meant to stand for (if anything). I am aware that the Q code was designed for a time when morse code was king and the Germans were the enemy. These days it seems more like the internet is king and the Germans make all the best cars.
I have never flown a civil transport jet with a strip DI as its main heading reference.
Now, when you say "Unlikely that it came from radial since they weren`t invented then" are you perhaps referring to VOR radials?
I think there may be some confusion between the radio theory use of the word "radial" and the common every day and navigation first principles meaning of "radial".
We all know that the radio signal transmitted by a VOR ground station is different in each different direction from the station. This of course is in contrast to the signal being transmitted from an NDB ground station where the signal is the same in all directions, hence the "ND" part of "NDB" standing for "non directional".
So you might suggest that since NDBs transmit the same signal in all directions that on a radio theory level they do not in principle use unique "radials".
But I would advocate a more common sense approach - which also happens to more neatly fit in with navigation first principles. I refer to a popular dictionary,
"RADIAL : like a radius, branching from a common centre"
and
"RADIATE : to emit rays, to spread out as if from a centre"
In a navigation context I could offer a definition of radial such as "an imaginary straight line starting at a defined position and continuing forever in a defined direction". Note that this could refer to an NDB - or a VOR - or any known point on a map. Sometimes this might be called a "position line".
The benefit of using the term "radial" when talking about NDB navigation is that there is no confusion about bearings being TO or FROM, radials always being FROM the ground station.
I do not know what the "R" in "QDR" was originally meant to stand for (if anything). I am aware that the Q code was designed for a time when morse code was king and the Germans were the enemy. These days it seems more like the internet is king and the Germans make all the best cars.
Guest
Posts: n/a
Yes BIK_116. (Where is that?).
I was addressing your comments.
1. Who said anything about civil transport jets ?. Mine doesn`t have a fixed card ADF either but I would suggest that if you`re still grappling with the theory of intercepting QDMs and QDRs when flying a civil transport jet you`re in the wrong job.
Some civil transport aircraft still do possess strip DIs though not as a primary reference - that would be the P type compass (with mirror). I flew one not that long ago - certainly more recently than when Bill Dodd and I did it in black and white.
2. My bit about radials actually agreed with your use of the term - I wouldn`t quibble. How would you do "Radial radial radial - XXX request radial"?.
" XXX what kind of radial would you like - a QDM or a QDR ?".
Anyway the best sort of radials have cylinders.
3. I was only getting hooked by your anti Q code thing. Personally I enjoy the strange and arcane terms we use - not for the bafflement of the poor proles who don`t have the faintest idea why we fly - but because they`re fun. However I do admit to having enjoyed the ATPL theory, and thinking that we should all use sextants.
4. I think 3 greens has got his answers but as usual they would probably be best drawn on a piece of paper.
Gazza.
[This message has been edited by Gary Halliday (edited 01 January 2001).]
[This message has been edited by Gary Halliday (edited 01 January 2001).]
[This message has been edited by Gary Halliday (edited 01 January 2001).]
I was addressing your comments.
1. Who said anything about civil transport jets ?. Mine doesn`t have a fixed card ADF either but I would suggest that if you`re still grappling with the theory of intercepting QDMs and QDRs when flying a civil transport jet you`re in the wrong job.
Some civil transport aircraft still do possess strip DIs though not as a primary reference - that would be the P type compass (with mirror). I flew one not that long ago - certainly more recently than when Bill Dodd and I did it in black and white.
2. My bit about radials actually agreed with your use of the term - I wouldn`t quibble. How would you do "Radial radial radial - XXX request radial"?.
" XXX what kind of radial would you like - a QDM or a QDR ?".
Anyway the best sort of radials have cylinders.
3. I was only getting hooked by your anti Q code thing. Personally I enjoy the strange and arcane terms we use - not for the bafflement of the poor proles who don`t have the faintest idea why we fly - but because they`re fun. However I do admit to having enjoyed the ATPL theory, and thinking that we should all use sextants.
4. I think 3 greens has got his answers but as usual they would probably be best drawn on a piece of paper.
Gazza.
[This message has been edited by Gary Halliday (edited 01 January 2001).]
[This message has been edited by Gary Halliday (edited 01 January 2001).]
[This message has been edited by Gary Halliday (edited 01 January 2001).]
