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Guest lbowes

ILS Approach with the B737-600

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Guest lbowes

Hi all,I am having a really annoying yet basic problem. When I create a flight plan with a STAR for an ILS app the plan always has me intercepting the ILS @ about 3-5 dme from the runway @ about 2000-3000ft. I thought the standard length for a final is 10nm, so why is it giving me a 5 nm final? I'm assuming here that the FMC can work out a correct intercept path. At the moment I have to vector myself to allow enough distance for a DME. I would be grateful if someone could point out what I might be forgetting to do.ThanksLuke

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There are questions relating to your questions. ;-)What do you mean by final and "the plan has me intercepting"?Is ATC involved here?The typical glideslope intercept occurs around 5-6 miles out, while you would intercept localizer 7-10 miles out. When STAR typically ends there is enough 'slack' to be correctly vectored for the ILS with ample of room since a typical STAR ends a good 10+ miles away from the runway. It is really a job of ATC to put you in the right place. Maybe you should show us what STAR and approach you fly since if you mix wrong STAR with some approach weird things may happen.Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2

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Most STARs are not intended to put you on final. They are intended to get you in the general area so that ATC can vector you to final. If you're flying a precision approach (i.e., you select an RNAV or ILS runway), then the FMC should connect the dots between the end of the STAR and the runway. If you simply select a runway number, then the FMC will take you from the end of the STAR directly to the end of the runway, resulting in a very short final.To solve this, there are three things you can do:- Add a 10 mile runway extension to the runway. This is done on the ARR page after clicking on the runway number. The extension LSK is below the runway number you select. This will add a waypoint 10 miles out on the runway approach.- Fly the approach manually (visual approach), with a longer final.- Select a precision approach from the runway options.If you fly on vatsim (or in real life), you'll learn quickly that the end of the STAR is often discarded and ATC will simply vector you to final somewhere in the middle of the STAR.-Jared "Smitty" Smith

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Guest lbowes

HiThanks for your replies, just to clear up I'm not using ATC at the moment for my 'test flights'. I do select a precision app after the STAR but when the FMC 'links up the dots', it turns from base to final @ about 5 dme which is a bit short? I suppose I could just vector myself as ATC would for 10dme. I thought though that like other add-ons (A320 PIC) when you select a precision app and do it without ATC the FMC still turns you for final @ 10dme to allow time for app.ThanksLuke :-)

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Luke,What airport and procedure/runway are you trying this on?Can you give us a screenshot of what you are seeing as a problem?Hope it helps,

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Guest tmetzinger

>Hi,>>Flight is EGLL-EGCC, STAR is Dayne2A I think, screenshot>included. FMC turns me in for final at less than 5 dme.>>Hope this helps,>Luke.>>http://forums.avsim.net/user_files/111514.jpg>If DAYNE is the end of your STAR, then the normal procedure would require a controller to vector you from DAYNE out a ways and then bring you back inbound to the localizer.My GUESS is that the STAR actually calls for you to expect vectors to final sometime before reaching DAYNE.you can work around this in two ways:1. - add a new waypoint after DAYNE - try DAYNE035/20 and that would force the airplane to intercept the localizer at a friendlier distance.2. On the leg to DAYNE, select HDG mode and give yourself vectors outbound at a 45 degree heading, then when you're abeam INN8.4, turn right to 90 degrees, fly that for a minute, turn left to 270, and hold that until you intercept the localizer.... you just flew a procedure turn.

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Guest lbowes

Thanks very much for your post Timothy. I'll vector myself then before Dayne. This is what I used to do but then I got the A320 PIC add-on, in this add-on when you select a STAR followed by an ILS app it just plotted an 'ILS friendly' course for you so you didn't need any vectors (if there are no ATC online).ThanksLuke :-)

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Is there a reason you picked this particular STAR? Were there other STARs available?. If you have a choice always pick a STAR that gives you a better 'fit' with your instrument approach.Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2

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I flew into Stansted on Saturday as a passenger on a Ryanair 737-800. According to the chart I found on the internet, the localiser intercept is at 6.6nm and this seemed to be more or less what happened. I could see the runway clearly out of my window on the left side of the plane before and as we turned to line up. From wings level to touch down was 2 minutes 10 seconds. John

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Guest glenb

JohnIf you could see the runway and it was only 2 min then I doubt it was an ILS approach.

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>I could see the runway clearly out of my>window Most likley the weather was good and they flew a visual approach.Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2

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Guest canyonblue737

also once you begin to vector yourself for the ILS a good technique to remember is to extend the runway centerline of the approach for yourself. on the LEGS page for example if the FAF is named "RUNTS" then bring RUNTS to the scratchpad, bring it back up to the L1 key (to get the flightplan into "MOD") then enter the intercept course (you can use the ILS inbound course, or more accurately use the course displayed on the CDU between the FAF and the RW) and make it sure it is entered and bold in the 6R position. Then execute the changes and the centerline of the runway will extend to infinity. This is handy so when ATC clears you to join the localizer you can use LNAV to join which is smoother than using VOR/LOC. Once established inbound on the final you can turn off LNAV and arm VOR/LOC or APP and the autopilot will very smoothly transition. happy approaches...

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Hi,Please do a search on the forum, as im sure i have posted numerous times on this topic, including using VNAV on approach. The best thing todo when not using ATC is to use heading select to take yourself out a bit. Then give yourself a good intercept heading of about 20-40* angle from the Localiser. Then use your VORLOC to establish on the LOC then further use the APP hold to capture the glideslope. Regards,Ross

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