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Question regarding autoland3

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HiI've been trying out the autoland function and i'm going through some trouble on some airports. I usually plot in a navfix for the runway i'm heading to in the FMC and then align and use autoland3. But on some airports it's not aligning correctly vertically and lands the 747 100-500 feet (maybe more sometimes) before the actual runway starts. I'm thinking I did something wrong with the "baro bug"? Thanks for the help, i've been going through the type rating courses and the operating manual trying to find some answers, but to no avail :'(- Takenobu Tou

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Hi There,ssssst... Listen before you get nuked by the guards there is a custom here (some call it a rule) which impose posters to sign their messages with their real name.To your question now, are you using any weather when flying? are you using the correct DA for the specific runway you are trying to land on?Can you give us more details as to which airports / runways you are having these difficulties and maybe interesting to know too which aircraft you are using.Best regards

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Ah i'm sorry, I didn't think there were specific rules, that's my own fault for not checking that first. I'm using real weather data (15 min) from the FSX settings. I'm flying the PMDG B744 and last time I was trying to land at 27R at EGLL. I flew from my departure airport directly to LOGAN (fix) and had ILS27R in FMC (DEP/ARR).So when I aligned with 27R from the fix LOGAN I hit the LOC and the AP with L/V NAV checked. It aligned perfectly with the lateral part of the GS but it was too far below the glideslope vertically, and it didn't stay on the alt to capture it, meaning it tried to land me in the buildings short of the runway. It disregards the information in the legs when it's set to autopilot right? I was thinking that when DEP/ARR was set correctly and it had caught the localizer it would know if it was too low or too high. But I think i'm doing something wrong here... - Takenobu Tou

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A screenshot would help us figure out your problem. Are you sure LOC is captured and your not just flying the LNAV VNAV path to the runway? When the Aircraft captures the localizer that is lateral path. You need to be on the Glide slope for a correct vertical path (with your altimeter set correctly)Rob

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Sounds like you're not using the correct vertical navigation mode. If you're landing in Autoland the modes should indicate LOC for lateral and G/S for vertical. If you have anything else on there it's not landing properly.My understanding of the approach is as follows... 1 - Turn towards the runway to intercept at 50 degrees or so from the runway heading... when cleared to intercept localizer, select LOC on the MCP.. Usually at this point speed is under manual control and I dial in my required speed... probably 180 to 200 depending on traffic.2 - As the aircraft lines up with the runway and you tell ATC, they will clear you on the ILS approach, at this point I arm APP.. and check LOC is green and G/S is armed in white on the MCP.3 - Once the aircraft pitches down for the glideslope descent I set the MCP ALT to my missed approach altitude.. Usually at this point at 160knts.. Wait for the 3 autopilots to become active too..4 - At 4NM to go (common practice I believe for separation) I reduce to landing ref and at this point my flaps etc should all be configured.If you're LOC is working it suggests you're using the right ILS frequency so I would say it's not that. If your modes are not LOC and G/S with ROLLOUT and FLARE armed for lateral and vertical control, you're not in an autoland configuration.. VNAV should not be armed or active on the final descent to the runway.. You should see LAND3 on your PFD too, not CMD... CMD is not a landing autopilot mode.. I'd really need to see screenshots of your FMC legs page, MCP and PFD to see what was happening..Hope this is of some help, put up the screenshots and we can help..CheersCraig

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It is highly likely you're using your VNAV mode to land with, often approaches to runways within the FMC contain detailed height data that guides you to the point of touchdown. Often you'll see legs with 614 feet, 214 feet, etc.. If you're in VNAV and your MCP is set to 0 feet, then VNAV can continue to descent as the vertical path within the FMC instructs it to unrestricted. But VNAV is NOT.. a landing mode, it will not flare, it will ignore the glideslope and it will not work.. Sometimes you want to go manual you can let VNAV do it's job down to a low altitude and then take over manually for the final few miles.. However I'd always prefer to use the ILS even for that..CheersCraig

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Ok thanks for all the replies, I think you are right that I might be using the LNAV/VNAV incorrectly, so i'll try again and see if I can take a screenshot of my landing. Thanks for all the help!- Takenobu Tou

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Ok so I tried again, landing at EKCH 04R. I had put in the fix RNAV FIX BASLO and landed successfully!I took two screenshots:1) 2D Cockpit - http://i26.tinypic.com/2v3mutz.jpg2) Virtual Cockpit - http://i31.tinypic.com/2v331gm.jpgI noticed it did switch correctly from CMD to LAND3 and displayed rollout/flare. Please disregard the fact I forgot to extract my flaps to 20...Thanks for the help guys!

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Your PFD modes and MCP switching appears OK.But apart from being 20 kts below your Flap 10 speed, isn't your altimeter under-reading by at least 480 feet? I'm at the limit of my knowledge here, but I believe if you press B it will update the captain's altimeter with the QNH in use. Whilst your Radalt is indicating 180 ft, it looks like the yellow ground indicator is 300 ft above your present altitude. "We all live in a yellow submarine..." ####, I'm showing my age. Another suggestion is that there might be a mismatch between the AIRAC cycle you're using and the FS database - really not sure of that one, though.David "jumbojock" Robertson

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Ah i've only calibrated it manually with the bug before takeoff to the dep airport, but forgot you could update it in flight - I take it that's what it does when you press B?- Takenobu Tou

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Yes or do it the real way by using the BARO knob on the EFIS control panel. Hope all your landings are smooth 1500 ft down the runway now.David "jumbojock" Robertson

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Ah yes, thanks a lot for your help!I just want to thank everyone else who replied too!

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If you want to get a bit more advanced and realistic, try loading the actual ILS approaches into the FMC DEP/ARR page instead of just inserting a single fix along the runway centerline. Most major airports will have all the approaches in the FMC and you can follow the exact marker waypoints that real pilots would etc...

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Piggybacking Ryan's suggestion, instead of selecting a runway for landing, you selected an ILS on the DEP/ARR screen, and most approaches have one or more transitions. This way, you can fly the approach from the initial approach fix (IAF), which is what's required real world unless you're vectored to final approach course by ATC. Approaches start at the IAF, and GS intercept is generally the final approach fix (FAF) - by which time you will already be close to landing configuration.Edit: Took another look, I notice you only have 10 flaps. You should be in final landing configuration before you descend below 1000 agl (above ground level)... and I notice your packs are off?

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Yes the above post is correct, this is not the correct procedure at all... I think really you'd benefit from a detailed description of the landing process.. If you've got this far it would be worth going the extra mile and learning about the STARs etc.. These are the approaches stored within the FMC.I also notice that your MCP set altitude is 00000, it should really be your missed approach altitude at this point.. The EGLL to LAX tutorial approach and landing section would be worth you reading. It covers a hold, approach and autoland landing in some detail into Los Angeles, this is found in the PMDG OPs pages. Take a look at that, have a read and see how you get on afterwards.CheersCraig

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One detail: normally localiser (or VOR) interception at an angle of 30

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Thanks for all the advice and explainations. I know there are a lot of things I haven't gone through yet, but I thought I would keep it simple for starters and add more things along the way. I'll investigate about adding more details to the approach. Note: I'll have a look at the type rating courses again. Although the attached savegames appeared to be FS9 i'll figure out something.Thanks again!- Takenobu Tou

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After about 1500 hrs on the 744 , I had another first . . .NO failures programmed!After eng start etc and taxiing to rnwy I noticed a yellow warning> NO LAND 3The book says :Determine cause - correct as desiredAny explanation and hints for correction ?Karl-Heinz - EDDI/THF " Tempelhof "" The mother of all airports " - Sir Norman Fosterhttp://www.precisionmanuals.com/images/forum/747400.jpg

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So I read the Type Rating Course IV which covered some SID/STAR. I only have two questions then:1) When I look up KLAX on airnav.com I find a lot of SID and STAR charts where PARADISE FOUR is just one of many. If i'm flying alone with no ATC or just with the AI, do I just pick one SID for take-off on the runway I want to use and a STAR matching the rwy where I want to land? I just want to know how pilots know which SID/STAR to use :)2) When I plot in all the information from the STAR and follow the course down, do I just manually plot in the fixes from the IAP chart? Before I used the DEP/ARR and selected a runway, but when I did that it'd put in a lot of fixes by itself. I couldn't understand from what I read from the type rating course (IV) if I was supposed to use the DEP/ARR or not. I'll try to boil it down (i'm obviously not good at explaining things) - should I use the DEP/ARR to select a runway or just plot it in manually from the information I get from the STAR and IAP?I came to think about this after Don said I selected an ILS on the DEP/ARR instead of selecting a runway.Finally, when I look at IAP charts for say KLAX there are 3-4 types: ILS or LOC / ILS RWY (CAT I-III) / RNAV (GPS) etc. Usually I print out the ILS RWY charts, but I see they've printed out the ILS or LOC for the type rating course 4. Do you use a special set for when using STAR?Ok that was more than two questions - Thanks!- Takenobu Tou

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I couldn't edit my previous post so I created a new one.I think i'll follow the long haul tutorial I dug up on the PMDG OPS site, so i'm sure i'll have all my questions answered there!

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Taxying out? All the aircraft is telling you is that it doesn't have the necessary redundancy for triple channel autoland. There are many things that could cause this from ILS failures to electrical problems. From a flight sim point of view I don't know how to sort this out other than making sure you went through your start up procedure to the letter and making sure that there are no failures programmed in either MSFS and PMDG. Hope that helps.David "jumbojock" Robertson

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1) One of the first things the pilot will listen to when first in the seat is the ATIS (either that or receive it through ACARS). This will tell him which RW is in use. Sometime during the FMS set up before departure, they will contact ATC for departure clearance, which will issue the necessary SID dependant on which RW is in use and which airway the aircraft will be following. As you're flying with no ATC, you determine the RW and select the SID from the DEP/ARR page(s).(Note: unless it's a very short sector (LHR-CDG) the arrival at the other end will not normally be selected prior to departure.)2) When selecting an arrival, 99 times out of 100 you'll be selecting an approach, not a RW, for arrival. Pilots will be assigned a STAR again dependant on direction of arrival and RW in use. This may change several times in the decent in the real world, and so a friend of mine came up with the reminder, "Why me?" or Y-M-E.a. Look at the buttons on the FMS CDU, and pick out the DEP/ARR, LEGS, NAV RAD and INIT REF buttons. They form a Y.b. To set yourself up for an arrival, first select the DEP ARR page; from there select an approach using the right hand select keys (eg ILS RW 08), then a transition underneath if it has one, then a STAR from the left hand list.c. Before executing, select LEGS and make sure that the whole approach agrees with the published STAR. When you're happy, press the EXEC key. This answers your question about building an approach - you shouldn't be doing that if your sim nav database agrees with your printed material.d. Now select/pre-select the navigation aids required for the arrival. Note: the ILS should already have been selected by the FMS.e. Press the INIT REF button. The approach page should already be there; select your Vref depending on which flap setting you're using.f. Finally, make any MCP (the M) and EFIS (E) selections you might require. Eg you might be in Heading Select whilst changing the runways and forget to go back into LNAV for the arrival.On your last point, and going back to what I said earlier, your STAR and approach should dovetail together, ie you won't get an easterly STAR for a westerly runway.Phew!David "jumbojock" Robertson

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Hi DavidThanks for answering all my questions. This certainly cleared everything up! First I was intimidated by looking at the SID/STAR's heh. I'll go over it a few times, and with the tutorial in hand and all the good things everyone has written down here it can't (shouldn't) go wrong :)Note I saw from the long haul tutorial you could set up the FMC to do a HOLD, how cool is that. I'm getting more and more surprised with all the "little" things they've put into it. That's all for now!- Takenobu Tou

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Assuming you're looking at my EGLL to KLAX tutorial, there is a lot of information in there but it doesn't go into a lot of detail regarding nav aids for the approach and also how to interpret the charts. I am going to be working on a revised version which will include everything, including much more detailed planning and weather..SIDs and STARs are a very important part of IFR flight. The SID is the departure procedure and the STAR is the arrival. Pilots will have an idea of which SID and STAR they will be using based on their route, and also the weather conditions at the airfields...If your route departs north, and the wind is east to west, chances are it'll be a BUZAD departure from Heathrow, if it's west to east, WOBUN... There are different variations of these depending on the exact runway you're taking off from, WOBUN has 2 variations, corresponding to Heathrows 27L and 27R runways. In the office, pilots will get their routing information, the predicted weather at the field and more than likely it will be done for them, but an appropriate SID selected based on the weather and the stand position. If you're on the south side of Heathrow, you'll probably favour a 27L departure for example, it means you don't cross runways and it means a short taxi time. To taxi to 27R, you'd have to cross 27L (which will be busy) and also taxi right across the airfield. All these factors are taken into account. So before boarding, and getting clearance, Pilots will probably have programmed their expected and filed departure. They'll be able to quickly change this though if ATC cannot meet their requirement for one reason or another. Shouldn't take a more than a few minutes, easy to do at the stand before the push.. You could even change it while taxiing to your assigned runway. Essentially, before even boarding the crew will have an accurate picture of weather, alt setting, SID, weight well before they get to the stage they need clearance.. Nothing in the clearance should be a big shock..Same goes for the STAR, these will more than likely be pre-planned, but probably not entered, especially for long haul, weather can change unexpectedly at times making that effort a waste of time. But the crew will have a good idea what to expect and their plan will reflect this. ACARS will keep the crew up to date with respect to destination weather, active runways, and as they get closer they'll refine their expectations.. Not only will the crew do this for the destination, but also for all the alternates on route. Sometimes utilising the RTE2 function of the FMC to programme in the expected STAR for the current alternate airfield to save time in an emergency.As they approach, ATIS for the field will confirm their expectations, their stand will probably to some extent dictate their landing runway, which they'll have thought of... again.. by the time they get their approach clearance it shouldn't be too much of a surprise.. Even the taxi is considered before landing in most cases.. If you watch the Virgin 19 DVD.. you'll notice Alan discussing the taxi during the approach... Saying what exit he expects tower to ask them to use.. and the route to their stand.. which by now will be confirmed.Not sure if that's too much information, but I wanted to make sure that you appreciate in the real world these things are very calculated.. everything is planned and co-ordinated.. At an airfield like Heathrow, it needs to be!CheersCraigPS - Definitely, fly the EGLL to KLAX.. I am sure you will learn a LOT.. it's well worth it.. that's what I wrote it for.. Even if your flights are a little different, it should give you the knowledge to be able to do handle the aircraft properly on your own.

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Hi David,I know what it means . . .On each flight since almost 3 years I follow the same procedures and check-lists - NEVER EVER this came up before !In the book for other failures and warnings it says :DO THIS or THAT - but here nothing . . .Will see if it comes up again.Karl-Heinz - EDDI/THF " Tempelhof "" The mother of all airports " - Sir Norman Fosterhttp://www.precisionmanuals.com/images/forum/747400.jpg

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