Jump to content
Sign in to follow this  
Guest iQue

The bumpy auto landings....

Recommended Posts

Guest jacaru

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

Share this post


Link to post

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 |

Share this post


Link to post
Guest iQue

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

Share this post


Link to post
Guest Zapper

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,

Share this post


Link to post
Guest jacaru

that chat would be great.Jaime.

Share this post


Link to post

Hi Brad,Would definately be interested. Thanks,Mike


Mike Normandeau

Montreal, Canada

Share this post


Link to post
Guest Zapper

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,

Share this post


Link to post
Guest wee_davie_2612

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

Share this post


Link to post
Guest Zapper

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,

Share this post


Link to post
Guest wee_davie_2612

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

Share this post


Link to post
Guest iQue

>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.Brad,I have made a recording for you.I added you to my MSN-list so I can send it that way. The filesize is 3,7 Mb. Thanks :-waveFrank

Share this post


Link to post

Guys,I have made three autolands in the last couple of days and although more trickier than before, I can say that it appears to work great.Armen L Cholakianwww.veryquiet.com


Boeing777_Banner_DevTeam.jpg

 

 

Armen L Cholakian
PMDG Sound Engineer

Share this post


Link to post
Guest schmidtrock

No bumps here ! Are we selecting the correct criteria from the APP page ? I don't understand the problems but feel sure it's no bug. I have never experienced the bump/skip whatever.Blue skies,

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  
  • Tom Allensworth,
    Founder of AVSIM Online


  • Flight Simulation's Premier Resource!

    AVSIM is a free service to the flight simulation community. AVSIM is staffed completely by volunteers and all funds donated to AVSIM go directly back to supporting the community. Your donation here helps to pay our bandwidth costs, emergency funding, and other general costs that crop up from time to time. Thank you for your support!

    Click here for more information and to see all donations year to date.
×
×
  • Create New...