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Guest JTH

Need help flaring please

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Guest JTH

Hi, yesterday I was flying the 747-400 and tried a manual landing once the plane was finished turning me onto a nice 10 mile final. I pulled the autopilot disengage bar, but left on F/D and A/T. I think on retrospect I should have turned off the F/D, not sure what if pilots are meant to leave the A/T on or not but I did find it very convenient to have the plane automatically stay at the Vref + 5 knots speed for me so I could just focus on following the ILS.Eventually the plane counted down "500", "100, "50" etc but I had a problem flaring. Basically I pitched up the nose but instead of gliding onto the runway the plane just flew in a straight line with its nose up about 50 or 100 feet above the runway. So I'm wondering is there is a set altitude, i.e. 100 AGL, where I'm meant to start flaring and also if there's a set nose-up pitch I'm meant to use? Also, not sure if this is right but when I did eventually manage to touch down I immediately turned off F/D and A/T and applied thrust reversers. When the plane's speed dropped to 80 knots, I stopped the reversers and throttled back to idle. Not sure if all this is the correct procedure, I'd appreciate any input.Anyways thanks in advance for any help. Regards, Paul.

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You should idle the trottles before touchdown, that way you will land when you flare and not carry on flying down the runway.I could not tell you exactly when to idle throttles but I am sure someone here will explain in detail. Good luck


Keith Sandford.

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Guest ColdBear

Hi,A little info regarding a manual ILS approach.http://forums.avsim.net/user_files/144546.jpgI usually start flareing about 30-50' AGL, and a max of 3-4deg added to the final approach pitch. The ground effect will help you when in the last 10-20'. Also remmember to disc the A/T, it is prohibited to use A/T without the A/P engaged.Martin

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Guest s_L_Y_F_a

reverse thrust should be set to idle at 80 knots and turned of at 60 knotsand martin are you really sure that using AT without AP engangend is forbidden? I know that Airbus pilots are allowed to use (and are using) AT on final without the AP enganged.

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Guest eham020

hey PaulIt's normal for most commercial crews to use the a/t during the final approach. However, it is always disengaged if carrying out a manual landing. At what stage during the approach depends largely on the individual pilot. Most crews I have observed like to get it done well before the a/p. I guess this is so they get a 'feel' for the throttles again, not having used them since just after takeoff. Unless the throttles are closed, the a/c will tend to fly on when you raise the nose to flare. Try thinking about it this way : During the approach, use the throttle to control the descent rate, and the stick to control the speed. Too fast ? Raise the nose slightly - then add power if needed to keep the descent rate steadyToo High ? Close the throttles slightly - then raise the nose if needed to keep your speed at vref+5Try this approach, see if it works.Make sure you have your autobrake armed, and the spoilers. (Check this on lowering the gear) Passing 800' AGL on the approach, disconeect the a/t. Disengage the a/p when you are ready, and try to ansure that you stay around Vref+5 all the way down using the pitch to control any changes in speed. On passing 50' (fifty feet), close the throttles fully, and gently flare the a/c onto the runway (angle of 3-4deg). Very little flare is really needed. The air squeezing between the aircraft and the ground tends to cushion and flare the a/c for you. I tried this approach a few times from 1000' in totally calm conditions, and most times, it landed beautifully without me touching the stick !!! The autobrake will bite immediately on touchdown, along with the spoilers to dump that lift. Focus on keeping the a/c straight, and when you are sure the a/c has fully landed, deploy the t/rev. Passing 80kts, disengage the t/rev and the a/b and slow the a/c steadily using manual braking until you reach your exit. I did this over and over again, then gradually worsened the weather conditions and a/c configurations each time. After a hundred or so approaches, I am now pretty good at landing this fabulous machine. Probably several people will disagree, or have another method. I would try them all anyway ! Andy

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1. I think boeing recommends that the A/T not be engaged during manual flight.2. U can't really compare the Airbus A/T system. It's a totally different system logic, and comparing the 2 sysstems for operational purposes may be dangerous to the point of porducing a safety hazzard.3. Most/All boeing planes are optimized when the A/T is ARMED during a manual approach, note ARMED, not engeged.With all that said, I immediately see the cause of the problem. U flew the approach with the A/T ngaged in SPEED mode. Thus, when you flare, the speed starts to bleed off and the A/T responds by increasing thrust. That's why the plane simply flew down the runway level. The A/T must be disengaged for a manual landing so that u can reduce power. U can touchdown with the system ARMED or disengaged, but the A/T can only remein engaged at touchdown during an autoland.Hope I've helped.Paul

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Guest simonmd

Personaly, when settled nicely on the glideslope and everything is stable, I make a mental note of the present N1 setting and turn the AT off as well. I'll then adjust the manual throttle so that N1 matches what is was on auto and continue the approach. Then, when about 50ft above the runway, I flare and idle the throttles together and she should settle nicely on the runway.

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Simon,Thats exactly the way to do it in the real machine,by checking what the FMC thinks the power should be then useing that as a base.We (I) tend to start the flare at about 30 RAregardsJon

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I have observed that when doing an autoland, the Queen often carries N1 power of around 35-40% down to the runway surface which is interesting because I always thought N1 should be at idle by the touchdown in fairly ordinary (i.,e., benign) conditions. I just landed in horrific x-winds of 28 knots with heavy turbulence and decided to carry power all the way down and did a touchdown with N1 of slightly under 50%. It was a firm landing to be sure, but better than going to idle in such conditions.I normally start reducing N1 at 40' to 50' AGL and pull back on the stick at 30' AGL to try and achieve a 4-5 degree pitch for TD at the 1500' markers. Jonathan


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Guest D17S

I like to hand fly, flight directed ILS approaches. I use clear weather to start, then I start bring down the visibility. I capture the ILS at a good 10 miles out, then get configured ASAP. I find part of the trick is to get the airplane configured and stable early. My company tells the pilots that either the airplane is configured and stable by 1000 ft AGL or they will go around. No questions asked. Using the AT can be helpful, but it has to be disengaged prior to flare. That's where I was always getting into trouble. The action of trying to find a click spot at that critical moment always distracted me to the point that I just lost it (i.e.,GS or the LOC). In the sim, I've found the only realistic way to deal with a manually flown approach (with the AT engaged) is to map an AT disco button into my controller. I'm just not good enough to be able look away even for 2-3 seconds. That is the absolute worst moment to be distracted. But using the AT only gets you half the thrill. You can do it, without! For my hand flown, flight directed approaches, once I'm established on the ILS I swap my focus to the vertical speed needle. A typical GS will be about 700fpm rate of descent (ROD). If I watch the V/S indicator, I get an 'early warning' that I'm about to drift hi or low. For instance, by catching a ROD that drifts to 800FPM and nudging it back to 700 fpm, I can catch a GS excursion before the dot even moves. But how? I use the V/S indicator as a kinda

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"I have observed that when doing an autoland, the Queen often carries N1 power of around 35-40% down to the runway surface which is interesting because I always thought N1 should be at idle by the touchdown in fairly ordinary (i.,e., benign)"When the engines are told to idle, the high speed rotor (N2) speed is controlled to a specific value based on a number of parameters. N1, basically, just goes along for the ride. Maintenance tables show that _N1_ at approach idle can be (in rough figures) from 31% to 37%. The engine must maintain this speed until around touchdown... give or take a few seconds. The idle speed can't be allowed to get too low as it would be unsafe during a go-around. After touchdown, the engines go to a lower idle speed... although use of reversers can keep the engines at the higher value.Hope this helps.Cheers.Q>

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Guest JTH

Ok, thanks everyone for the detailed responses. I've read all of them and with the new info I've learned I tried another flight today.To be honest, one basic problem I'm having is that I haven't fully grasped how to use the ILS in the 744. The plane flies a route, with the last waypoint called "RWY 22" for example. So it makes it's last turn towards the RWY 22 waypoint (not heading 220 degrees though). In the flight today I was about 25 miles out from "RWY 22". So basically could anyone explain HOW I know: a) when I'm established on the glideslope :( when I'm established on the localiser? I didn't know whether I had the G/S or LOC or not but at about 15 miles from "RWY 22" I pressed the "LOC" and "APP" buttons on the MCP. The LOC button lit up but when I pressed the APP button I got an FMC message saying "NAV invalid". Basically then the plane did not proceed on the correct course to runway 22.So if anyone could help to clear up the whole ILS issue for me it would be much, much appreciated. Thanks a lot for everyone's continued help!!

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>Ok, thanks everyone for the detailed responses. I've read all>HOW I know: a) when I'm established on the glideslope You see green "GS" on the primary display. (NOT white)> :( when I'm established on the localiser? You see green "LOC". (NOT white)Michael J.http://www.precisionmanuals.com/images/forum/pmdg_744F.jpghttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg


Michael J.

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Guest D17S

Sounds like you have selected a

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Guest JTH

Okay thanks a lot again to everyone for the help, especially D17S. I went through your step-by-step and today completed my first non-tutorial flight, which I'm very pleased about!A couple of small follow up questions though.1) What are transitions ("TRANS" in the FMC)? When I selected my approach as "ILS28" I saw that it offered me a few differend transitions for that approach but I didn't pick any.2) What exactly do I do when the plane autolands and touches down? I tried engaging thrust reversers but they didn't seem to engage at first presumably because A/T was on. Do I switch of the A/T as soon as the back wheels touch the runway and start thrust reversing?3) At what stage do I instruct the plane to slow down to my Vref + 5kts speed? Is it when I'm lined up on final at about 5-10 miles out?4) Is there a better way to read the ILS on a manual landing? What I mean is, all that the ILS seems to be showing the pilot is an arrow pointing left or right and up or down on the PFD. It doesn't really tell you HOW MUCH to turn left or right or HOW MUCH to climb or descend, unless I'm missing something. The more conventional glideslope indicator in the ND seems a lot easier to use, but there's no left-right indicator unfortunately.5) What does the LOC button on the MCP do? I just hit "APP" as you said and the plane followed the localiser and glideslope path. Is the LOC (localiser?) button just for for where you want the plane to control left-right navigation while doing an ILS landing and where you want to control the up-down movement (glideslope) yourself? Hope I'm making sense here!Anyway thanks everyone once again and hopefully I'm not overdoing it with all the questions. Regards, Paul.

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