7/21/2023 0 Comments When to intercept localizer![]() ![]() Here is were problems start: the LOC diamond comes in too slowly as the FD commands an intercept angle of no more than a pair of degrees. At this point the 310 is on final, at D9 from runway treshold, centerline of runway being slightly on my right side,almost parallel to my heading. The LOC diamond slowly comes in from the right, then LOC* green. Flyover COM-09 on NAV, left turn on final mantaining 3000ft. 1 mile before COM-09 leveled at 3000ft, speed down to 170kts, Flaps 20/20, Gear down. Leaving COMISO VOR at 5000 started descending for 3000 at 180kts dct to COM-09. Ok tested the approach using V/L on the LICB ILS05 procedure, all programmed in the FMS. I'm not fying the A310 in real life but the principle is more or less the same (just a question of SOP). In my SOP again (depend airline of course) we have one last trigger at 500ft RA where the PNF call "500, STABLE, TARGET, SINK xxx", mean that by no lower than 500ft the PF should be on LOC, GLIDE and at the targeted Vspeed and the PNF announce the sink rate. Of course if not stable it trigger the go-around. in real life the 1000ft RA is the limit to be stabilized and configured for landing (stabilized in LOC/GS and Vapp SPEED ) and in my SOP it trigger the "1000" call by the PNF and the "STABLE" reply by the PF. ![]() One suggestion though, in the last video you are little bit late configuring and slowing down the plane. In the real life airliner I'm flying that can happened (even in CAT 2) when little bit away (12-15 nm DME), the A/P is struggling a bit to maintain LOC centered but that disappeared when around 10-8 nm out, at that point the A/P follow just perfectly the LOC/GS, even with some crosswind. ![]() On those 2 videos it is obivous that the A/P is little bit lazy correcting the ILS. It seem that the FD struggles in intercercepting the LOC, particularly when steep turns are needed and the purple diamond cross the midline rapidly. If U want to try the above procedure, i think that u can reproduce the scenario. GS was properly followed and the poor a310 crashed on the ground, 1 mile parallel to the right of the runway. Despite this, the FD did not command the required left turn to correct and remained in the center, with LOC* green and purple diamond on the far left side. At 3000ft and 9miles from Comiso VOR the plane started the left standard turn (180kts speed selected) but when LOC* activated it didnt follow properly the purple diamond, wich passed the centerline and then stayed on the far left. LVCH and NAV were active and LAND mode was armed (LOC/GS blue). I was coming from LICC (Cagliari), so the whole arrival procedure was in the FMS. I tried the standard ils rwy5 procedure at Comiso (LICB). It doesn’t hurt anything, after all.The localizer capture needs major fixing in my opinion. So the one airplane that day that is already established when they get the clearance, likely gets the “Maintain 1600 until established” as a matter of routine. So, while you may be already established, the controller may or may not know that, and even if they did, they issue the whole PTAC routine hundreds of times a day – so often that it literally just rolls off the tongue without much thought. The list of things the controller is required to tell you is in FAAO 7110.65W, para 5-9-4, and is typically summarized as PTAC:Ī – Altitude, Maintain XXXX until established Typically you are on a vector to intercept final when the controller issues the clearance, so you are not yet established. “Also, why does controllers mention ‘maintain 1600ft until established~’ even when A/C is already established on localizer (CDI centered) ?” Realistically, I would just intercept the glideslope at 1600, that to me is better than descending 100 feet, leveling off, and then descending again – more power and trim changes than are necessary. You can do either, as either one is in accordance with your clearance. “Let us assum that you are currently at 1600ft, can I descend down to 1500ft or just intercept GS at 1600ft?” However, I will assume you mean the ILS 18, which does have GS intercept at 1500. If you were, that’s a foul on ATC’s part and you shouldn’t accept it. The KPIE ILS 36 has glideslope intercept at 2000, so you should not be cleared to intercept at 1500.
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