Back Course Approach (EGPF ILS 05)
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I'm trying to figure out how to do a Back Course ILS approach as described in the manual (pasted below for reference), using EGPF(Glasgow) ILS 05 as a reference.
From what I understand from the first sentence, I should set my CRS to the reciprocal of the final approach course of 048, which is 228. I'm set up to intercept the localizer from a 20 degree angle with VOR/LOC armed (roughly 030). However, when it captures, instead of turning right, the plane turns left, away from the runway. (I had previously tried this with 048 as the course, but IIRC the localizer diamond was on the wrong side).
Any ideas of what I'm doing wrong?
From the manual:
Back course approach
Tune the localiser frequency and set the course pointer to the front course QDM of the localiser. Back localiser
(BLC) mode is armed when the VOR/LOC button is pressed with the aircraft track greater than +/- 100 degrees of
the selected front course.
Note: If the aircraft track subsequently transitions to within 100 degrees of the selected course prior to capturing
the localiser, the armed mode will revert automatically to LOC.
Ensure the BLC1 or BLC2 (white) legend is shown on the PFDs and that the vertical deviation scale shows
BKCRS.
When the aircraft approaches the back localiser, automatic capture will occur. At capture the BLC (white) legend
will change to BLC (green).
After localiser tracking has begun, the descent phase of the approach should be initiated, normally using V/S
mode. The appropriate missed approach altitude should be selected in the MCP ALTITUDE window.
VS mode should be selected to give the appropriate descent rate, the A/T may be used to control speed.
Note 1: Use of the localiser display on the standby attitude indicator is not permitted for back course guidance
because the azimuth display will be in the reverse sense.
Note 2: A back course must be flown coupled to the FD and/or AP, otherwise uncoupled raw azimuth data on the
PFD can contradict the ND.
Note 3: The altitude selector must be moved away from the initial procedure altitude in order to select VS mode -
I don't know why you would want to do this. EGPF runway 05 has a front course ILS system. My guess is that's why trying to do a back course ILS is not going to work properly.
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stevekane - ITRW the use of an ILS LLZ back-course requires to be promulgated as useable. Today they are found less often than they once were as the use of a back-course assumes that an ILS (LLZ and G/S) is only available for one end of the runway. However, from reading what you have write I’m not sure you are doing the proper procedure.
If you wish to make a back-course approach for EGPF 05 then you would use the ILS for R/W 23 frequency and front course of 23. And for an B/C approach to 23 it would be the ILS 05 freq and front course for 05.
Apologies if I have misunderstood what you are trying to say you are doing.
FYI, I’m told that there are no longer any B/C procedures within Europe or UK.
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Following up. In my case, when I was trying to intercept ILS RW05, it was indicating BKCRS on the right side of the PFD, leading me to believe that this was a Back Course ILS, which I'd sort of heard about but have never tried (no, I'm not a RWP yet). The Locator bug was on the right when I expected it to be on the left, so I decided to switch to RW23
The conditions were LIFR, so I decided to switch to RW23, but also got the same weirdness. I somehow managed to land by hand-flying the LOC/GS bugs (Flight director was still directing me away from the approach course, so AP was no help). (If real-world, I'd certainly have diverted.)
Did this same scenario a day later, same result.
Did it yesterday, but realized previously that I'd tuned the ILS on NAV1, but had the Glasgow VOR tuned on NAV2 (FO side) just for additional DME data. This time they were both tuned to the ILS, and everything worked perfectly, both runways.
Unsure if this is expected? With JustFlight, I'd be 90% sure this is by design and not a bug.
I'll try this again tonight, maybe switching NAV2 between the ILS and VOR to see if this is really the cause.