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Help With Tutorial Missed Approach to MCO

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In Tim M's tutorial I am doing everything by the book but my plane ignores the holding track completely. I execute the missed approach, and re-engage LNAV and the AP per the tutorial. I head on the magenta course at about 210 deg. I'm at 2000 feet as instructed then I get a FMC chime to "reset mcp altitude." I can't see why, cause the hold is for 2000. Then I arrive at the oval and the plane turns to 141 degrees and continues on without turning onto the track. Happens every time. Any ideas what I'm doing wrong?? Thanks. Tom

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Which approach and whose sidstars (Navdata, Planepath or Dan Downs)?

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Sorry Dan, I thought I had included that info. I am doing the tutorial flight 4 into KMCO, the ILS18R. The missed appr outbound is on the magenta line at about 210deg. The plane arrives at the holding track and turns onto the track to about 141deg, then instead of turning right onto the track, it ignores the turn and heads out straight on 141deg. I have LNAV set and am at 2000 feet per the tutorial. I am using the default database. Thanks. tom

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If I understand, you arrive at the holding fix (Kissimmee NDB) then tracks away from it to the SE... that's strange. It should either enter directly by flying outbound 327 or a teardrop entry by flying outbound 282 then in either case turn inbound.Maybe your problem is the "default data." Current AIRAC and SIDSTAR data is highly recommended, but you are in a situation at KMCO where the current data has a runway that doesn't exist in the default FS9 scenery (17L/35R). What you do next is up to you... you can upgrade the scenery and get the current data (recommended) or you can try to get around this by trying the last free airac cycle (0609) and a current sidstar (from navdata). This might be a problem because I don't think the 0609 airac had the new runway and any current sidstar will give you an error, which you can get around by editing the new runway and runway numbers ... but this is getting complicated for anyone new to this stuff.Maybe there's something else going on besides the old data, but I can't spot what that might be with the info provided.

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Thanks Dan,I am also working with Tim M himself, and he is also baffled. It obviously works for him as he is the one who wrote the tutorial. I sent him a screenshot of the missed and am waiting a reply. Here is the same shot I sent him right after it ignores the track. Thanks again. Tom

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I just recieved the 747 and am new in this forum. Who is Tim M, and were can i get his tutorials? Thanks Bob

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Hey,Timothy M. Metzinger wrote a few very good tutorials for the 737NG, due to some copywright problems he had to stop distributing these.http://www.metzair.com/flightsim/flightsim.htmlAnyway, if you google (PMDG 737NG Advanced Operations Manual) you will find the tutorials out there..Its only for the 737NG, not for the 747 as far as I know of.Alex den Boer

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Thanks,Alex. You know I just got the PMDG 737 about 2 weeks ago.I'v been using this really good tutorial for it, its right here on my desktop. Oh look its by Timothy M. Metzinger. Da! somtimes I need to take my head out of my butt:-xxrotflmao . Thanks, and have a good one. Bob

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I notice you still have flaps out. I wouldn't start that turn either with flaps out at that speed... notice you are just below the red dashes.

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Good news and bad news: Good news - it's not anything you're doing wrong - I flew to MCO today in the -800 and had the same issue. After going missed, selected direct ISM on the LEGS page, engaged LNAV, SPD, and ALT HOLD at 2000. Airplane flew to ISM, then made a left turn to a track of 147 and did NOT sequence to the hold. Bad news - I don't know WHY it didn't sequence properly. SID/STAR file (Dan's) looks fine (no surprise there). I'm going to try some other airports and see what happens.-Tim

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Did some approaches at Dulles and they worked fine. At MCO, the course from the runway to the ISM is almost a perfect 30 degree intercept angle, which makes me wonder if the problem isn't that the autoflight system can't decide which entry to use. so I'm going to play with the approach a bit and see if I can't add another leg to it so it will be a more obvious entry, and then see if it will capture the hold. If I succeed I'll post the modified SID/STARS file for others to try.

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OK, here's my theory..ISM is very close to the MCO airport, less than 10 miles, and because of that the normal sequence of events doesn't give the FMC much time to do it's calculations and execute the hold.A workaround for this particular problem is to fly the procedure using HDG and ALT HOLD for the first shot around the pattern, and then LNAV should work for the additional laps.I'm going to continue to work on this.

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Tim: I like your theory that the 30 deg angle might have something to do with it. As for the distance... maybe but there's lots of IAPs with holds at the FAF, albeit that involves a 180 change after aborting the approach. One of you could change the sidstar text from it's current INBOUNDCOURSE value to something different and check it out.

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I don't want to change the inboundcourse value since that's how the hold is published, and changing the track flown to ISM didn't help much (see below). However, if you fly PAST ISM, turn around, and go direct back to it, it works every time.I did have some luck changing the procedure so that it required a turn to 270 after 500 feet, and then intercepted the 007 radial from ISM. But that was some pretty radical manuevering (a 90 degree right turn, followed by a 83 degree left turn). Lesser values (fly hdg 240 and intercept the 017, for instance) didn't work.What I think I'm going to do is try what you did on the misseds for the RNAV - send them over ISM, then arc them back to it and join the hold, and see how that works. If it works consistently, I'll forward the text.But for now, if you want to fly it as published, you need to do it manually (or in HDG mode) until you've passed ISM and are inbound to ISM again.Light bulb just went on - I'll try it in LNAV on the flight director, but controlling the airplane manually. What I've observed is the airplane starts to turn a little too early and never crosses ISM (closest point is .3 NM), and that may be why it doesn't sequence to the hold. So this time I'll fly right over ISM and see if the sequencing happens.

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Afterthought: I'll make this change to the KMCO sidstar for next cycle (0705) due out later this week unless you report it has a problem. Thanks.

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I'm going to test this:APPROACH ILS18R FIX HAMMY AT OR ABOVE 3000 FIX TUFFE 2200 FIX IVODE RNW 18R TRK 184 UNTIL 500 FIX ISM TRK 180 UNTIL 2 FROM FIX ISM TRK 327 UNTIL 4 FROM FIX ISM HOLD AT FIX ISM RIGHT TURN INBOUNDCOURSE 147 ALT 2000 LEGTIME 1.0And then if it doesn't work I'll try coding some colocated fixes with direct legs between them.

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OK, I've got the problem identified and solved.The default procedure (climb to 500, then direct ISM and hold) doesn't work because the turn anticipation in the PMDG starts the turn to intercept the outbound course of the hold a little early (probably because I fly it at 220, at 250 it might work), and the airplane doesn't fly close enough to ISM to trigger the sequence to the hold.If you keep the flight director in LNAV but do NOT engage the autopilot, and overfly ISM, then the sequence engages and if you engage the autopilot after overflying ISM it will hold correctly.To make it fully automatic, I've added two new fixes to define the first teardrop for the holding pattern entry:FIX ISMHLD1 COLOCATED ISM 297 8.0 FIX ISMHLD2 COLOCATED ISM 327 2.0Now the procedure overflies ISM, then turns right and overflies the first point, then turns right to the second, and finally there's a 2 mile leg to the holding point and holding begins: APPROACH ILS18R FIX HAMMY AT OR ABOVE 3000 FIX TUFFE 2200 FIX IVODE RNW 18R TRK 184 UNTIL 500 FIX OVERFLY ISM 2000 SPEED 220 FIX OVERFLY ISMHLD1 TURN RIGHT DIRECT FIX ISMHLD2 2000 HOLD AT FIX ISM RIGHT TURN INBOUNDCOURSE 147 ALT 2000 LEGTIME 1.0I've attached the corrected SID/STARS file.

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Thanks, Tim. I'll affect the change to kmco for cycle 0705.

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