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The bumpy auto landings....

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Hi all!I just wonder about the bumby autolandings. I thougt this would be fixed when this new update came but when I did a testflight today whith a 737-800 I noticed that it's even worse than before, about five to seven bumps before it came to rest on the runway. I have tried different flapsettings, diffrent speedsettings (vref+5 and so on) and I can se the flare. This is the only problem I have with this bird. Before the release of the 800/900, v1.3 of the 600/700 the autolanding where perfect. But since I installed the 800/900 autolandings has been bumpy for all the models. I hope somebody can help me and others whith this problem, it's truly take away the fun in landing this bird. (With autopilot :( )Otherwise, thanks for a great product! :)Please help :-zhelp

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Hi Frank,Had a thought, I always get bumby landings when I come off the power to late (to close to the flare). Are your reducing power to idle? If so when?

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What I do with this plane (which I've seen done here in SJU), is I take her down the ILS at a relatively stable thrust... Then, when you get around 100ft from the ground, throttle up around 30-40% until the rate is reduced more or less to where you want it. Once that's done, idle it. It'll do wonders, the additional thrust will eat a tiny bit of runway, but it's worth the smooth landing (if you're not on short field operations).Daniel P.http://www.precisionmanuals.com/images/forum/ng_driver.jpgMember of SJU Photography. [A HREF=http://www.jetphotos.net/showphotos.php?userid=9004]Click Here[/A] to view my aircraft photos at JetPhotos.Net!The official psychotic AA painter. :)

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I'm sligthtly confused here. Firstly my autolands seem to work fine including after the updates yesterday. My confusion is down to the talk of throttles. If I'm doing a fully coupled autoland I never touch the throttles as the Autothrottle does all this for me. I just configure the flaps, autobrakes and set the speed (VREF +5) on the MCP and let the plane do the rest. As the wheels touch down the Autothrottle automatically disengages. Following this strategy seems to provide me with a perfect landing everytime.I'd be interested to know if my procedure is wrong in some way, although even if it is I will need some convincing to change it :-)

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Same here George. Are you landing with full fuel? I don't know how the autoland is programed, but it might just change the attitude of the aircraft?? And so if it's heavier it might take longer for the aircrafts descent rate to reduce (I don't know much physics, so i'm probably talking b@lls here). Anyway, the moral of the story is are you landing with a reasonable amount of fuel? ...and whats wrong with manual landings:D Much more fun...:(

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Hi and thanks for all helpMy landing rutines are exact like Geoffs..but it still bumps :-hmmmI also have tried different amount of fuel and payload.When I get home I will try the throttle tip and see if that helps.And yes, I know it's more fun whith manual landings :D but I want autolandings work too :9:-waveKind regardsFrank

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When will this be fixed?Manual landings are nice, but hey, if the real aircraft can do autolandings without bumping, shouldn't we be able to do it in the sim?CheersMartin

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>When will this be fixed?>>Manual landings are nice, but hey, if the real aircraft can do>autolandings without bumping, shouldn't we be able to do it in>the sim?Yes I think so too. Specially when it worked perfect before the 800/900 upgrade. (At least for me)Would be nice if PMDG team could tell something about this. Yes I know this has been up before but I never seen any explaination what's causing this from the PMDG. Only that it perform autolandings as close to the real thing and you have to watch it, but I can hardly belive that it bumps like this in real life. (-:So, maybe someone from PMDG?ThanksFrank

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Daniel,you may have a good result but this is a technique which should be used to often.It's better to have a firm landing, than a soft landing.The bumps...must be a wrong landing speed as normally if you fly the approach Vref+5, and idle the throttles at about 30ft AGL, you'll have an airplane wanting to stay down in stead of an airplane wanting to fly. add a good pair of speedbrakes to this and you're set... not more bouncing... autolands may be automatic, it's still the pilot's job to continuously monitor the computer's actions and correct if necessary(that's why a CAT3 autoland can be so intense(i say CAN))Personally i'd never give extra thrust on finals, since you're a good bit above the stalling speed(times 1.3 correct??) you have room to do a better job on the flare. the autoland's flare is basically 'crap' but it'll give you a presentable touchdown rate IF you are on the right speed. Speed is everything on approach... remember that.Coming in too fast will make you bounce because there is enough 'energy' to get the plane up again, at the right speed, this is not so.

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I'm certainly glad people like you and not Martin are training for real world opertaions Lenny ;-). Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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Glad not to have to fly with you in a pit Randy ;) Good that you are far far away. :)

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just did a test flight... works perfectly for me...

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Martin, i'm trying to understand your problem here...i'm not sure why you're getting the bumps so would you be so kind to provide full data of your final approach stage? i.e. weights, configuration selected(my test was FLAP30 ... seamlessly), speeds used, weather?, perhaps you can shed info on your body attitude on short final(before the flare command engages(so when it's armed => white))the more info you give, the better pmdg can try and answer your problem.Asking for 'fixing' the problem is a bit out of place here Martin, we should first discover the why ... but i'm pretty certain it's not a mistake in the programming...Best regards,

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Martin does not care about this aircraft, all he cares about is trying to make it look bad and the Ariane good but as we know that will take a miracle not silly posts in a forum!Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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hello,I'm having the bumpy autolandings too. The first thing to asume is that i am doing things wrong on my side. I have to say that frankly i yet dont understand the autoland procedure to a full extent. Being a full autoland, i shouldnt disable autopilot nor autothrottle prior to touchdown, isnt that correct?? Even if its not autoland, its not common to disable autothrottle...so how am i suposed to go idle?The sensation i got is that either the airplane comes in too fast or that the flare starts too late. The vref the fms is giving me its higher than the reference speed for the flap setting paired with that vref.Yesterday i got an vref of 148 knts for 35

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Wrong guess again, Randy. I am trying to find out why my PDMG 737-700 does bumpy autolandings. And it looks like i am not alone. if it's a bug, it will need to be adressed. That's fact. ;)Does this sound reasonable to your brain ??CheersMartin>> Martin does not care about this aircraft, all he cares about>is trying to make it look bad and the Ariane good but as we>know that will take a miracle not silly posts in a forum!>>>Best Wishes,>[h4]Randy J. Smith[/h4]>[h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]>Caution! Not a real pilot, but do play>one on TV ;-)>>AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA>@535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows>Xp Pro | Windows Xp Pro 64 |

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Hi againAfter reinstalling the 737,I just did some autolanding tests at EKBI in Denmark with 737-800.My GW was about 62T.FMC Vref speeds15=15230=14540=138Autobrake set to 2Clear weather and no wind.I tested every flapsettings 4 times like this. Vref, Vref+3, Vref+5, and Vref+7. The only difference is the attitude before the Flare, then the same bump at touchdown. Anyone who like to test some of this settings and report their expirience? I also tried this at a GW 56T and same thing happend. It seem Impossible to me to do a autolanding without the bumps..If I just knew why :-hmmmRegardsFrank

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Gents,I fly the AFDS an awful lot in the in the PMDG sim. It flies excellent Cat3A autolands every time. Before running off at teh mouth and insisting that there is a prob with the sim why don't we all have a chat online and perhaps we can discuss your operating techniques to ensure we are doing it right initially. There is only way way to operate a Boeing and that is the Boeing Way :( I have done hundreds of autolands in the real world in visiblity where you can't see the runway until you are well past the threshold and the PMDG sim replicates the performance exactly. No autoland is a greaser but it attains the most important criteria of any landing, ON THE SPOT AND ON THE SPEED. Greasers 800M into the LDA are for people that want to preen their egos in front of the passengers ... accurate landings in the TDZ are what airman make. Remember that.So let's have a chat before we all become armchair experts eh? It may be that there is a problem ... but let's get some quantative data first.I trust this post is will be recieved in the same way it is written, as a genune attempt to help simmers get the most out of the best civvy flight sim I have encountered in 23 yrs of PC flight sims.Rgds,

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that chat would be great.Jaime.

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OK.. I will be online for a chat at 0408032000Z. The chat will be at the usual TS server, if you do not know how to do this please see my homepage where there is a quick tutorial on it.Also, for those who do not (yet) know how to read the above time:It is the international standard method of expressing time and is used by all pilots everywhere. {DTG or Date Time Groups} are in a 10 figure group and list the first 2 numbbers for teh year, next two for month, next two for day, next two for hrs and last two for minutes. Think of it as being groups of two numbers starting from the biggest unit of time ( a year) and move sequentially down to the smallest unit (the minutes)Note: for ease of use DTGs may be shorted to the relevant numbers ie. If it is obvious that we are dealing with something in teh next few days we may only put the day and time ie our chat will be on 032000Z.Just to make it even easier:0408032000Z is 3rd August 2100hrs local in London (they are on daylight saving atm) 3rd August 1300hrs in LA, 3rd August 1600 USA East Coast and on my side of the world will be 04AUG 0800hrs in NZ and 04AUG 0600hrs in East Coast Australia.This may also be of assistance:http://www.timeticker.comPls let as many interested ppl know as you can.Rgds,

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Hey all,Just to add to the list. I'm experiencing the bumpy autolands aswell. I wouldn't describe it as a bump though, more of a skip.I think it could simply be down to landing at high gross weights and thus needing a higher power setting to maintain Vref+5 on final. With a higher power setting it'll obviously take longer for the engines to reach idle and will most likley not reach this idle before touchdown. Basically it is the same as having a touch of power on upon touchdown when performing a manual landing i.e. it'll skip. This is probably why this phenomenon is only noticed in the big beasts which have an extra five tons able to be added to Max landing weight.The test I flew today was at Glasgow (EGPF) in the -800, rwy 05 was active and the winds were 088/11. First time round the gross weight was 142300 lbs (Max landing is 144000lbs BTY) flaps 30. Everything dandy except for the small skip upon touchdown.Basically the same thing happened on the next approach except flaps 40 was used and the landing wieght was 139700lbs.I'll try again with the aircraft a bit lighter and see what happens.Have a good one,David

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Any chance of someone making a video recording of these bounces for me?.. Iw ould like to see it from the outside with aview of teh control surfaces.Tks,

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Hey Brad,Not sure how to make a vid but if you can tell me how then I'll do it.I describe it as a skip because I'd term a bounce as becoming airborne again after touchdown (just like a football, you throw it to the ground it bounces and then becomes airborne again). A skip, on the other hand, can be described like a flat stone skipping on a pond - it'll touch then float inches above the water then touch again. Still technically becoming airborne again but you get what I mean.The heavy 738 is doing an impression of a flat stone. It'll come in perfectly right through the flare but as the mains touch down it'll skip back up a little (we're talking inches not feet here) and then within two seconds its feet are firmly on solid ground again. The aircraft holds the flare attitude right through this skip.I'm still going with my theory about the higher power settings :-)Have a good one,David

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