Pineapple_Wizard

Landing the 777, what's going on?

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So recently I've found a rather strange and annoying issue when landing the 777, both the 200LR and 300ER. This is in P3Dv4.1 777 version 1.10.8448. So I fly most approaches manually but with the autothrottle engaged. Upon touchdown, it seems that sometimes the airplane doesn't quite register it is on the ground. I hear the speedbrakes coming up, but the PFD speedtape glitches between NO VSPD and how it normally is during flight. At this point the nose is still up and the aircraft is not decelerating even though the throttles have come to idle. I also cannot seem to activate the reversers either. Autobrakes were set at 2 and still no deceleration. It wasn't until I forced the nose down that I heard the touchdown sounds and the reversers deploy. I've also seen this happen to twitch streamers before while landing the 777. In the options I also have A/T override in flare enabled. For some reason, replicating this issue is difficult, it usually happens during a normal flight, as today it happened upon landing at EHAM from KSFO. Now if I just load in the 777 on a runway, takeoff just as is, fly a pattern, and land manually, everything works as it should. I also use FSUIPC but only for autosave and do not have any controls mapped with it. Any help is greatly appreciated. -Thomas Swehla

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Hi Thomas. It sounds like you are coming in hot, slow down.  In normal conditions the 777 is landed with A/T engaged but you set the speed on the MCP.  Be sure you are stabilized at Vref+5 by 1000 AGL and don't overflare in your landing.  The A/T will retard the throttles around 30 AGL and it takes a few moments for those huge fans to spin down and there is some intentional delay to accommodate a go around before the flare. This delay is what the override in flare addresses (Intro pg 92).  It is normal to use reverse thrust after the mains are on the ground with the nose still in the air, you might have to hit F1 before  F2.

What are you using for throttle control?

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Yeah I usually approach at Vref+5, stabilized by 1000', I try to follow the FCOM I have. The flight into AMS was 152 kts on final with the autothrottle. It idled at 30ft like it usually does but on touchdown the plane seems confused, I can't the reversers open until the nose wheel comes down. Also worth pointing out that it does not decelerate at all. You could literally go to the end of the runway still at 150 kts with the nose up. I haven't been able to check the exterior view often when this happens, but the one time I did, the spoilers couldn't decide if they were extended or retracted and the main gear was bouncing a bit. These even happens with hard landings. For throttle control I use a Logitech Extreme 3D pro. It is rather old and there may be some noise on the throttle axis but I don't know if that would affect it.

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Full name on all posts here please Thomas.... PMDG rules.

Noise from the throttle is a problem. Sounds like your autobraking is being cancelled too because she will stop without reverse thrust, just further down the runway.  Reverse thrust is most effective at high speeds, so try hitting F1 before hitting F2 to see if that works.  How does your controller handle reverse thrust?  My Thrustmaster Warthog has throttle levers that lift over a gate and move into reverse thrust, but there isn't a reverse thrust axis.  The gate is actually a switch and I have that programmed in FSUIPC to send an F1 then F2 repeatedly.

The 777 is very easy to land... you might have a problem with configuration?

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Try landing at a default airport to rule out scenery layering problems. To me it sounds that it might be the case. If you land at a default aiport and the plane behaves normally, you have isolated the problem to scenery install, flattening and layering.

 

Good luck..

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Okay I'll have a look at trying F1 before F2. As far as my controller, it just goes down to zero, in others words it does not handle reverse thrust.  Whenever I land I just tap F2 to get into reverse. Thomas Swehla

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4 hours ago, Pineapple_Wizard said:

Okay I'll have a look at trying F1 before F2. As far as my controller, it just goes down to zero, in others words it does not handle reverse thrust. 

Can you set the throttle position arrows to show on the N1 EICAS display and then see what the throttles are actually doing as you are landing?  That might help isolate the problem.

Mike

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Rule of the thumb is that u disconnect A/P, then also u should do the same with A/T and vice versa.

Watching real movies on YT, i see that pilots do exactly like that.  

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9 minutes ago, Beardyman said:

Rule of the thumb is that u disconnect A/P, then also u should do the same with A/T and vice versa.

...but not on the FBW aircraft like the 777 and 787, where Boeing SOP is to keep the A/T engaged in both automatic and manual flight.

I can only think of one operator that requires the 777 A/T to be disconnected in manual flight; I can think of several (including some big ones) which say it must not be disconnected in normal ops. Where discretion is permitted some pilots may choose to do so but it is not the standard way of operating the aircraft that Boeing intended. 

This is different to the older aircraft with a thrust/pitch couple.

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On 1/4/2018 at 5:34 PM, xkoote said:

Try landing at a default airport to rule out scenery layering problems. To me it sounds that it might be the case. If you land at a default aiport and the plane behaves normally, you have isolated the problem to scenery install, flattening and layering.

 

Good luck..

It's strange I've had the issue at Flytampa AMS before and I've also had no issues there. Today I landed at T2G LFPG and had no issues. Strange, I'll try to record my landings and post a video of when it goes wrong. Thomas Swehla

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I've had the same problem as the OP since I upgraded to the B773.  It doesn't matter if it is Autoland, autothrottle only, or all manual.  It seems more related to the nose not wanting to come down.

blaustern

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On 1/5/2018 at 4:53 AM, skelsey said:

...but not on the FBW aircraft like the 777 and 787, where Boeing SOP is to keep the A/T engaged in both automatic and manual flight.

I can only think of one operator that requires the 777 A/T to be disconnected in manual flight; I can think of several (including some big ones) which say it must not be disconnected in normal ops. Where discretion is permitted some pilots may choose to do so but it is not the standard way of operating the aircraft that Boeing intended. 

This is different to the older aircraft with a thrust/pitch couple.

Wasn't confusion on this issue the cause of the Air Asiana crash in KSFO?

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10 minutes ago, PATCO LCH said:

Wasn't confusion on this issue the cause of the Air Asiana crash in KSFO?

Not really; the issue there was more that the AFDS was in an entirely inappropriate mode (FLCH) for the phase of flight and, on top of that, the flight directors were not being followed in manual flight.

FLCH is a speed-on-pitch mode with fixed (in the case of a descent, idle (generally)) thrust, so if you don't follow the FD pitch commands Bad Things happen, like not achieving the target speed.

Better FMA awareness and more active monitoring in general should have caught the situation.

51 minutes ago, Bluestar said:

It seems more related to the nose not wanting to come down.

I'm not a B777 expert but I do have access to some manuals and I do recall reading a note to the effect that the B777 exhibits neutral pitch stability and therefore certainly on a touch and go the nose requires actively flying down with forward pressure. On a normal landing however I would have expected the pitch-down effect of braking/reverse etc to assist in bringing the nose down somewhat, but I'm not sure.

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Gentlemen, the FCTM has a chapter on landing with pages of information including charts. Do your homework.

Landing Roll FCTM 6.26 "Fly the nose whells smoothly onto the runway without delay.  Control column movement forward of neutral should not be required." If you require forward movement of control column to plant the nose gear then I suspect your flare angle and/or speeds are incorrect.

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Regarding Asiana, as I recall, they were too high and decided to use FLCH to go down more quickly.  However they had already set the go-around altitude, which they were below.  So the throttles increased and the aircraft tried to climb (VNAV doesn't do this if the aircraft is more than 300 ft below go-around altitude -- VNAV will continue to follow the descent path).  So they manually forced the throttles to idle, which put the autothrottles in HOLD (I have been unable to get a PMDG 777 to simulate this, but it is a weird situation not normally encountered).  I believe they switched off the autopilot at this point, but the throttles remained in HOLD.  They did not realize this, and failed to pay attention to the airspeed, presumably because they assumed the autothrottles would maintain approach speed.

Regarding the problem of no autobrakes or reverse thrust until the nose wheel comes down, I have never experienced it, but I am using FSX (Steam).  I wonder if this is only a P3D issue?

Mike

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6 hours ago, downscc said:

Gentlemen, the FCTM has a chapter on landing with pages of information including charts. Do your homework.

Dan,

Was that addressed to me?

blaustern

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Hi guys,

This is how it look likes.

It's clearly something wrong in the flight dynamics. Look at how the speed is increasing while the A/T is in retard mode.

I had to brake manually for the nose to come down.

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Now THAT looks exactly like the confirmed issue with the 744.

Have a look yourself:

 

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never had ANYTHING like that with the 777 while I can reproduce the 747 issue. 

how do you load into the 777? 

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With respect to the 777 being easy to land.....I have noticed that this plane does not seem to flare quite as easily as the 737 or 747. I actually disengage AutoThrottle at 1000 feet (just like I do with the other two planes), but I appreciate that this is probably not normal procedure.

I just thought that I would mention it :smile:

Edited by Christopher Low

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3 hours ago, Christopher Low said:

With respect to the 777 being easy to land.....I have noticed that this plane does not seem to flare quite as easily as the 737 or 747. I actually disengage AutoThrottle at 1000 feet (just like I do with the other two planes), but I appreciate that this is probably not normal procedure.

I just thought that I would mention it :smile:

It‘s has always been a good manner to disconnect the AT flying airplanes with underwing engines. But since the 777 has fly by wire that automatically corrects the pitch movement when changing thrust it‘s not required to be turned off anymore. 

To be honest I have absolutely no problems with the 777. flaring it just means you increase the pitch just a little, and let it sit onto the runway...

„flare“ is -in my opinion - the wrong expression on all airliners anyway. You flare small props like a C172... or gliders. Hold them just slightly above the runway and let them fall and settle down just before they stall... if you did that with a 737 or 777 you would float for ages and strike the tail on every landing. You actually just reduce the decent rate and fly it onto the runway. With the correct speed it will stay there. But it‘s normal that you have to push the nose down a little in the 777. At least that‘s what Cpt Ashcraft says in the Airline2Sim training videos. I‘ve never attempted to land a real 777... only the 172 and gliders 😇

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Bumping this thread- I have been experiencing this as well with the 777 and it is very annoying. By the book numbers and I am confident there are no problems with methods, but it's like the plane just skips and skips (at idle thrust) until I force the nose down. I am sure it would skip all the way down and off a 12,000ft runway if I let it. Autothrottle in RETARD mode and it skips back and forth between NO VSPDS and VREF on the speed tape as this is taking place. Our ACARS also registers all (or most) of these as bounces.

This is odd because I have put quite a bit of time on the 777 since I bought it when released, and this is something that has been happening in the last few months or so. I'll see if I can post a video of it happening later tonight or tomorrow from in the cockpit. I stream on Twitch every so often and this has stopped me from doing so. Hopefully someone can find a solution or maybe PMDG can confirm/comment.

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I agree with Marc, flown correctly the problem with nose gear settling goes away.  Nothing has changed to the flight dynamics of this product in the last few months or so...., not sure why there are very few folks that complain of this. I'm not sure I'd know how to reproduce the problem other than to come in too fast and over rotate.

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28 minutes ago, downscc said:

I agree with Marc, flown correctly the problem with nose gear settling goes away.  Nothing has changed to the flight dynamics of this product in the last few months or so...., not sure why there are very few folks that complain of this. I'm not sure I'd know how to reproduce the problem other than to come in too fast and over rotate.

The problem is not the settling of the nose gear.... Kindly re-read the descriptions of what we are describing. I’m neither coming in too fast, nor over-rotating. In fact, I’ve tried landing with minimal flare to really plant the mains and it still happens. It may not be happening in your environment, but there are some of us that are experiencing it and that’s why we are posting here to see if anyone else has found a solution. I tend to lean toward something else causing this to happen but have been unable to narrow down what exactly it may be. I do not have this problem at all in the NGX.

Edited by FDX016 - Nick
Forgot the last bit.

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4 hours ago, FDX016 - Nick said:

The problem is not the settling of the nose gear.... Kindly re-read the descriptions of what we are describing. I’m neither coming in too fast, nor over-rotating. In fact, I’ve tried landing with minimal flare to really plant the mains and it still happens. It may not be happening in your environment, but there are some of us that are experiencing it and that’s why we are posting here to see if anyone else has found a solution. I tend to lean toward something else causing this to happen but have been unable to narrow down what exactly it may be. I do not have this problem at all in the NGX.

I did reread your description and there were no details, only that you are not planting the aircraft and have an unequal number of landings and takeoffs.  FCTM 6.8 is a good place to go for a review of 777 landing technique.  As for gust correction, anything added to Vref+5 should be washed out by landing where you should be at Vref+0 (pg 6.9).  For each 5 kts added for gust or whatever, the attitude should be decreased by a degree.  Mains touching down should coincide with throttles closing (autothrottle starts retard at 25 AGL).  Flare is 2-3 deg and you should be watching the far end of the runway to adjust rotation so that you don't float.

No one wants to hear that they have problems with their pilotage, but if you are bouncing the 777 and having problems with nose gear remaining in the air then there is room for improvement.

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