Intercept Loc Outbound
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Intercept Loc Outbound
Whats the exact procedure for Intercept LOC outbound on ILS chart ? ( not Back course chart ) .
Select NAV ( for Intercept Loc outbound ) with needle showing reverse sensing ? with outbount course or final course .
or
BACK (for Back course ) with needle showing correct sensing ? with outbount course or final course.
Select NAV ( for Intercept Loc outbound ) with needle showing reverse sensing ? with outbount course or final course .
or
BACK (for Back course ) with needle showing correct sensing ? with outbount course or final course.
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I cannot help with your type (Atr 72-500??) but generally it will depend on which instrument you are using.
If you are merely using an ILS indicator display, you would need either a 'Back Course' switch or to reverse what you do. This is because the instrument only knows whether you are left or right of the beam.
If you have the ILS displayed on an HSI, the HSI 'knows' the direction of the beam you are trying to follow (you set it in a window somewhere) and thus will know how to display the deviation so it is displayed correctly.
Edited to add 'Inbound course' set on the HSI
If you are merely using an ILS indicator display, you would need either a 'Back Course' switch or to reverse what you do. This is because the instrument only knows whether you are left or right of the beam.
If you have the ILS displayed on an HSI, the HSI 'knows' the direction of the beam you are trying to follow (you set it in a window somewhere) and thus will know how to display the deviation so it is displayed correctly.
Edited to add 'Inbound course' set on the HSI
Last edited by BOAC; 2nd Jan 2011 at 17:50.
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HSI to inbound course and fly the intercept and tracking in HDG mode. Thats my way..
My flying has me intercepting loc outbound atleast every third flight. This works perfect
My flying has me intercepting loc outbound atleast every third flight. This works perfect
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For ATR 72-500 & inst EHSI ,
Arm Back course for ILS chart is it correct procedure(we have to intercept LOC outbound only) ? because
for Back course there is special chart like ILS ??( INDIA we don't have )
Arm Back course for ILS chart is it correct procedure(we have to intercept LOC outbound only) ? because
for Back course there is special chart like ILS ??( INDIA we don't have )
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Never heard of such a "departure".Can you name an airport or post a chart,please?Only thing i know of is using the DME of the ILS for a distance to turn after departure(like @MRS)
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I don't really get it either.
Are we talking about the classic outbound radial followed by a left or right turn to intercept the localizer? In which case you would have the VOR tuned to track the radial outbound until a certain DME. Afterwards you turn in and switch to the ILS. Use the ADF if co-located to adjust your turning rate towards the localizer.
Are we talking about the classic outbound radial followed by a left or right turn to intercept the localizer? In which case you would have the VOR tuned to track the radial outbound until a certain DME. Afterwards you turn in and switch to the ILS. Use the ADF if co-located to adjust your turning rate towards the localizer.
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Sorry for wearied question ?
Actually asked to me for my ATPL viva ?
How you intercept Loc outbound ?
@ d105 - you got my question bit - after tracking outbound VOR radial we swich to ILS freq after that the question is - We go for Back course or arm Nav mode to intercept Loc outbound for this chart ?
Actually asked to me for my ATPL viva ?
How you intercept Loc outbound ?
@ d105 - you got my question bit - after tracking outbound VOR radial we swich to ILS freq after that the question is - We go for Back course or arm Nav mode to intercept Loc outbound for this chart ?
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Hiren,
You appear to be asking about flying to the VOR to begin the procedure, then flying outbound for the procedure turn. You didn't provide the entire chart, but if this is what you're describing, then your actions are fairly straight-forward.
You said you're using an EHSI display. With this in mind, set the inbound course. Forget selecting back course, as it's irrelevant, in this case. Set the inbound course and fly it.
If you have an EHSI, set the inbound course regardless of whether you're flying the front or back course, and you'll always have normal sensing.
Someone had asked about flying a backcourse outbound for a departure. This does happen in the Aspen, Colorado (USA) departure.
You appear to be asking about flying to the VOR to begin the procedure, then flying outbound for the procedure turn. You didn't provide the entire chart, but if this is what you're describing, then your actions are fairly straight-forward.
You said you're using an EHSI display. With this in mind, set the inbound course. Forget selecting back course, as it's irrelevant, in this case. Set the inbound course and fly it.
If you have an EHSI, set the inbound course regardless of whether you're flying the front or back course, and you'll always have normal sensing.
Someone had asked about flying a backcourse outbound for a departure. This does happen in the Aspen, Colorado (USA) departure.
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The departure is set up with a back course in order to provide normal sensing on the outbound course.
The airport has a localizer approach, using a different facility to the runway, but the back course beacon is set up for departure purposes.
You can see the relationship between the two facilities, geographically, as well as some of the surrounding terrain:
The airport has a localizer approach, using a different facility to the runway, but the back course beacon is set up for departure purposes.
You can see the relationship between the two facilities, geographically, as well as some of the surrounding terrain:
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Not having this kind of thing here in europe,how would I interprete the note "back course has normal sensing"?
Would a false capture on one of the beams happen if a LOC mode is armed to early?
Would a false capture on one of the beams happen if a LOC mode is armed to early?
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CptRegionalJet
To understand the "normal sensing" aspect, imagine that there is an ILS or LOC approach to Rwy 30 (again, imaginary) at Aspen.
You miss the approach and are required to track outbound on the back course. The "sensing" will be normal.
And I don't think it would be a good idea to use any lateral mode beyond HDG -- engineers who designed the avionics aren't likely to have contemplated a LOC signal growing wider in the direction of flight.
To understand the "normal sensing" aspect, imagine that there is an ILS or LOC approach to Rwy 30 (again, imaginary) at Aspen.
You miss the approach and are required to track outbound on the back course. The "sensing" will be normal.
And I don't think it would be a good idea to use any lateral mode beyond HDG -- engineers who designed the avionics aren't likely to have contemplated a LOC signal growing wider in the direction of flight.
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Hmm! SN3 - I think you may well have blown poor Hiren's brains there! Not the ideal chart to try to 'help with'?
1) There is no 'back course ILS that I can see - in my book the labelling of the outbound loc is mis-named.
2) I assume the localiser on the I-PKN has reversed lobes?
3) If it was a 'back-course' localiser, there has to be a 300 inbound course localiser - there is not.
This is simply a 'fudged' localiser for tracking purposes, not a 'back course'.
Hiren - I think you have got yourself more than a little confused here. Looking at your post to d105:
"@ d105 - you got my question bit - after tracking outbound VOR radial we swich to ILS freq after that the question is - We go for Back course or arm Nav mode to intercept Loc outbound for this chart ? "
1) Whyare you trying to "intercept Loc outbound" when you have turned inbound?
2) Which chart are you talking about?
Let's just stick to your original question. Why not look at the chart for LFLB (Chambery) in the French Alps? Take Jeppesen plate 10-3 and you will see that you need to fly the ILS R18 northwards on departure. To do this you select the EHSI to 180 inbound localiser course. The EHSI then shows your position in relation to the localiser correctly. On the 737 standby horizon (which has localiser left/right only) you also need to select 'Back Course' to see the correct display.
Please note I have no idea what 'NAV' does in the ATR EHSI.!
I suggest you ignore the charts for Aspen!
Edited to add (after a glass of Shiraz) that if SN3 can produce a 300 inbound localiser procedure chart on the I-PKN I will accept is as a back-course....
1) There is no 'back course ILS that I can see - in my book the labelling of the outbound loc is mis-named.
2) I assume the localiser on the I-PKN has reversed lobes?
3) If it was a 'back-course' localiser, there has to be a 300 inbound course localiser - there is not.
This is simply a 'fudged' localiser for tracking purposes, not a 'back course'.
Hiren - I think you have got yourself more than a little confused here. Looking at your post to d105:
"@ d105 - you got my question bit - after tracking outbound VOR radial we swich to ILS freq after that the question is - We go for Back course or arm Nav mode to intercept Loc outbound for this chart ? "
1) Whyare you trying to "intercept Loc outbound" when you have turned inbound?
2) Which chart are you talking about?
Let's just stick to your original question. Why not look at the chart for LFLB (Chambery) in the French Alps? Take Jeppesen plate 10-3 and you will see that you need to fly the ILS R18 northwards on departure. To do this you select the EHSI to 180 inbound localiser course. The EHSI then shows your position in relation to the localiser correctly. On the 737 standby horizon (which has localiser left/right only) you also need to select 'Back Course' to see the correct display.
Please note I have no idea what 'NAV' does in the ATR EHSI.!
I suggest you ignore the charts for Aspen!
Edited to add (after a glass of Shiraz) that if SN3 can produce a 300 inbound localiser procedure chart on the I-PKN I will accept is as a back-course....
Last edited by BOAC; 4th Jan 2011 at 20:08.
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Hmm! SN3 - I think you may well have blown poor Hiren's brains there! Not the ideal chart to try to 'help with'?
1) There is no 'back course ILS that I can see - in my book the labelling of the outbound loc is mis-named.
2) I assume the localiser on the I-PKN has reversed lobes?
3) If it was a 'back-course' localiser, there has to be a 300 inbound course localiser - there is not.
This is simply a 'fudged' localiser for tracking purposes, not a 'back course'.
2) I assume the localiser on the I-PKN has reversed lobes?
3) If it was a 'back-course' localiser, there has to be a 300 inbound course localiser - there is not.
This is simply a 'fudged' localiser for tracking purposes, not a 'back course'.
1) It's not misnamed. It's a localizer back course, pure and simple. It's just used for the departure, rather than for an approach. As a localizer, it has a narrower signal for the departure, and is aimed at a mountain pass leading to LINDZ intersection.
2) No, I PKN is a back course. There's no front course. It's installed this way to provide normal sensing while flying outbound, as the I-PKN localizer back course is used for a departure, and the missed approach for the LOC/DME-E, and VOR/DME procedures.
3) There doesn't have to be a front course. It's a back course. It's stuck in the mountains. It isn't flown as a back course to the airport, and neither is the front course; it's located physically on the other side of a mountain from the Aspen airport; there are big rocks between the airport and the transmitter. It's oriented as it is, providing back course guidance to give normal sensing on the way out on the departure and missed approach procedures.
It is a localizer for tracking purposes, and not for approach purposes (other than the missed); it's in very mountainous terrain, and serves as relatively precise guidance through and over a mountain pass. It is, however, a localizer back course.
Hiren - I think you have got yourself more than a little confused here. Looking at your post to d105:
"@ d105 - you got my question bit - after tracking outbound VOR radial we swich to ILS freq after that the question is - We go for Back course or arm Nav mode to intercept Loc outbound for this chart ? "
1) Whyare you trying to "intercept Loc outbound" when you have turned inbound?
2) Which chart are you talking about?
"@ d105 - you got my question bit - after tracking outbound VOR radial we swich to ILS freq after that the question is - We go for Back course or arm Nav mode to intercept Loc outbound for this chart ? "
1) Whyare you trying to "intercept Loc outbound" when you have turned inbound?
2) Which chart are you talking about?
He has stated that he's got an EHSI, and isn't sure how to follow it after flyin to the VOR, and intending to execute the approach. He needs to fly outbound for a procedure turn, and wants to know how to stay oriented.
Again, Hiren, set in the front course for the approach, and you've got normal sensing all the way through the procedure. No need to mess with a back course switch, and you won't have any reverse sensing. When you dial in the front course in the EHSI, your course needle going left will always mean you fly left. Your course needle going right will always mean you go right. No matter if you're flying toward the runway, or away from it. You get normal sensing all the time.
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Aren't you guys making this entirely too complicated?
Flying a back-course outbound is the same as flying a front-course inbound. Nothing tricky. Arm LOC, and have the front-course dialed in.
Flying a back-course outbound is the same as flying a front-course inbound. Nothing tricky. Arm LOC, and have the front-course dialed in.
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I didn't post it for Hiren's benefit.
CptRegionalJet suggested he hadn't heard of a departure using a back course
The concept of a 'back course' without a 'front course' is one I will pass on.
A bit like having a backing group with no 'star' up front or a back-up power supply with no primary.