The Joy and Anguish...

[ahuimanu 50]

Of hand-flying this aircraft to landing from approach.

Let me explain my typical procedures and other details:

• I fly the B777F exclusively in the 777 line - my aircraft is always the D-ALFA tailed Lufthansa ship.
• I will select the APP autopilot mode as I transition from arriving on the SID and I am otherwise on a track to intercept the localizer.
• I follow speed and flap schedules but generally I am transitioning like this:
  • From 10,000 ft AGL to around 8,000 ft AGL: I decelerate from 240 KIAS to the Flaps Up speed marker (typically around 230 KIAS)
  • Then, to Flaps 1 and 210 KIAS (generally Flaps 1 is around this speed) - altitude is typically from the 7,500 to 6,000 ft AGL
  • Then, to Flaps 5 amd 190 KIAS (generally Flaps 5 is around this speed) - altitude is typically from the 6,000 to 5,000 ft AGL
  • Then, to Flaps 15 and 170 KIAS (generally Flaps 15 is around this speed) - altitude is typically from the 5,000 to 4,000 ft AGL
  • Then, once Flaps 15 speed is achieved, I'll select Flaps 20, still at 170 KIAS - altitude is typically from the 4,000 to 3,000 ft AGL
  • Then, with the localizer captured, and as the G/S becomes active, I'll select gear down.
  • Then, with the gear down, I'll set speed to Vref + 5kts (plus gust 1/2 gust correction if required)
  • then, when the gear is down and I have three greens, I'll select Flaps 30, I am usually between 2,000 ft AGL and 1,500 ft AGL at this stage
• At this stage, I prefer to hand fly to touchdown and the anguish begins
  • I will first disengage the autopilot when the previous configuration is stabilized (I am at Vref + 5 with gust correction (if needed of course), the gear is down, spoilers are armed, auto-brake armed, and Flaps 30 is selected and indicated)
  • Once I am convinced that the I have a stable aircraft, and I've matched the physical power levers to the sim power levers, I'll disengage auto-throttle
  • Now, I realize that the aircraft is designed to use auto-throttles all the way down, but I fly the 744F in the same manner, so I try to remain consistent as I alternate between models
  • I follow the flight director bars and tend to only seek visual runway reference exclusively at decision height
  • As a side note, I have read/watched Denis Okan (watch his eyes in this video - https://www.youtube.com/watch?v=JqLTlpTPEHM) describe his preference to continue to closely follow the flight director bars even in visual conditions and his advice/perspective has stuck with me
  • At decision height (or a bit earlier if atmospheric conditions aren't too squirrely), I'll transition completely to using the visual runway environment as my sole cue for my flight path corrections
  • At decision height, my visual aim point is generally the touchdown zone markings
  • As the runway threshold passes by under the nose, I adjust my visual reference to be the end of the runway
  • When I hear "30" from the autopilot radar altimeter reading, I do my best to bring the nose up for a flare angle change of about 3 degrees or so - this is challenging to be precise as I have my eyes outside as a prime sensor for flight path correction
  • I am probably simultaneously bringing the power back here as well and I realize that the manual tells me to pull up the nose and THEN pull back power
  • I probably subconsciously pull back too much past the flare sometimes - I work on it, but this all happens in 10 seconds or so.
  • I try to be smooth in these last 30 feet, BUT...

No matter how I've played with sensitivities, I find that stick movement "feel" is disconnected more so than any other PMDG aircraft I fly.  I realize this is fly-by-wire, but the advice here in this forum still seems to be "fly it like a Cessna." However, I still maintain that there is a disconnect in feel here.  The control inputs required, and general feel, don't seem to be as "disconnected" for me in rotation, departure maneuvering, or arrival maneuvering.  However, on short final, where I find the finesse I can get out of the Queen (she hand-flies like a dream), I find a lack of fluidity in the movements I make for flight adjustments to be just disconnected enough to make consistent landings in the 777F very trying. I suppose what I'm saying is it feels like there is some play in the controls before the plane reacts and, thus, the latency makes fluid flying a challenge.  The Queen, on the other hand, is buttery smooth and I so enjoy hand-flying to landing in that aircraft.  On the other hand, it feels like a Monte Carlo simulation when I hand-fly the B777F to touchdown.

I have put 2000 hours into the B777F since June of 2017 (thank you 64-bit, I was so starved for long haul) and I average 8-hours per flight.  In the last 6 months, I'm more apt to hand-fly up to lights off +/- 5,000 feet.  However, my preference to hand-fly the last 1,500 feet of the approach has been in effect nearly the whole time.  I will perform an autoland when the conditions require it, but I find hand-flown approaches to be much more satisfying.

Lest you believe I should "git gud" - as the kids say - I've read the manual extensively and suggest that the 2,000 hours have provided ample practice.  Further, I've been simming since the 1980s, so I'm not a rookie.

As for flight controls, I use a Thrustmaster Warthog HOTAS, which provides me simming versatility and is a fairly great setup even for heavy iron.  I've certainly played with things like deadzones - usually needed for the MFG Crosswind pedals I use - and I don't feel that I'm using anything crazy. In fact, in roll and pitch, I have no deadzone as the Warthog stick is very smooth.

BOTTOM LINE

Help!?!?! What am I doing wrong? I can land the B744F smoothly flight after flight after flight (I put in an equal number of hours in the B744F from June 2017 until now), but I feel like its anybody's guess as to whether I'll come down in the touchdown zone at 75 fpm or slam it down at 600 fpm in the B777F with what I feel is the same techniques.  My "norm" in the B744F is around 150 fpm.

Now, I do use ActiveSky, so I concede that weather will always play a heavy role, but I would propose to you that I'm not crazy - there is something ODD about hand-flying the B777F and I'd love to discuss it and otherwise hear your perspective and thoughts.  I just want to have the same experience every week in the B777F as I enjoy in the B744F. Perhaps the B748F will cure me of this affliction but if it is also fly-by-wire and otherwise behaves like the B777F, I am concerned.

Thanks for reading my wall of text, I really would like to hear other perspectives.

Edited September 2, 2018 by ahuimanu
spelling and similar

[downscc 1,327]

The A/T really should be left on for landing, recommended by Boeing and others.  It is different from the 744, it is supposed to be.  The secret is trim for speed (not pitch) so turn on the trim speed indicator and keep your speed bug and trim speed indicator together.

The 777 does not need much in the way of rotation, just a few degrees of pitch up, less than you expect.  It is very important in a simulator to change your visual focus to the distant end of the runway and use that picture to gauge the flare and touchdown.

The 748 is not fly by wire... the outboard ailerons are electronically controlled but that alone doesn't qualify for the fly by wire moniker. I find the -8 a real joy to fly, probably the nicest flying aircraft in the PMDG fleet.  A real graceful lady.

Edited September 2, 2018 by downscc

[Christopher Low 5,331]

Quote

The 777 does not need much in the way of rotation, just a few degrees of pitch up, less than you expect.

I think that Jeff is trying to say (assuming that his experiences are the same as mine) that pulling the nose up when close to landing is actually more difficult than it is in the 747. I also disconnect the Autothrottle when stabilised on final approach, but the 777 does not flare anywhere near as well as the 747. I assume that this has something to do with the fly by wire control system?

Edited September 2, 2018 by Christopher Low

[ahuimanu 50]

You are right Chris, it is those last 50 or so feet which is vexing me profoundly - even after all this time. 

I guess I should operate the bird as intended - leave A/T on.  

Still, it is the flare angle and the throttle reduction "dance" that continues to be a problem. 

I'm 10 minutes away from another datapoint landing in LIMC right now, so we'll see again.

Thank you for the input so far, I really did hope a discussion would ensue.

[downscc 1,327]

1 hour ago, ahuimanu said:

"dance" that continues to be a problem. 

Focus on the far end of the runway will fix this.

[sosuflyer 30]

3 hours ago, ahuimanu said:

You are right Chris, it is those last 50 or so feet which is vexing me profoundly - even after all this time. 

I guess I should operate the bird as intended - leave A/T on.  

Still, it is the flare angle and the throttle reduction "dance" that continues to be a problem. 

I'm 10 minutes away from another datapoint landing in LIMC right now, so we'll see again.

Thank you for the input so far, I really did hope a discussion would ensue.

I know what you mean. I've had my joystick pulled fully aft trying to flare many times, and the nose never moved up at all and I end up slamming into the runway. I'll start with a slight pull on the stick, get no response, then gradually keep pulling the stick all the way back, still get no effect to the nose attitude of the plane. It's about 50/50 with me on good/bad landings in the 777. Something is weird about the fbw here. 

Also, I never feel the effect of the trim while in flight until I move the stick back to neutral. I've purposely tested it many times, same result. I can hold the stick back to maintain a 10° attitude, and while doing that I will excessively hold my trim up button that should relieve pressure on the stick, but nothing changes. Then when I return my stick to neutral, all that excessive trim up I applied will suddenly kick in, and my plane's nose will start rising. I love pmdg products, but the 777 will always be the runt in my lineup because of its weird handling. The 747 on the other hand, pure silk. 👌

[skelsey 765]

5 minutes ago, sosuflyer said:

Also, I never feel the effect of the trim while in flight until I move the stick back to neutral. I've purposely tested it many times, same result. I can hold the stick back to maintain a 10° attitude, and while doing that I will excessively hold my trim up button that should relieve pressure on the stick, but nothing changes. Then when I return my stick to neutral, all that excessive trim up I applied will suddenly kick in, and my plane's nose will start rising.

Disclaimer: I don't own/fly the 777.

However, from what I understand of the 777 trim: you are trimming for airspeed.

Therefore, if the airspeed isn't changing, you don't need to touch the trim. Now, in your example, if the autothrust is in and you have sufficient excess thrust to maintain the current/selected airspeed, you shouldn't need to touch the trim at all. Just select the new attitude and relax the pressure on the stick and the nose should stay where you want it (basically).

By running the trim in you are selecting a lower trimmed speed. This causes the nose to rise when you relax the pressure.

I think this specifically may be an issue with the way the FBW is replicated in a hardware arrangement where you can't feel the out-of-trim forces; in the real thing in that situation you wouldn't really be pulling against any force so it would feel natural to return the control column to neutral, whereas if the speed was reducing (for example, if you were at a fixed thrust setting) the aircraft would generate a force to be pulling against that you would then trim out.

The thing to remember is that fundamentally there is no mystery to the 777 trim -- the way it is described in the manuals etc is a technical explanation of how Boeing programmed a computer to behave basically how a very well-behaved non-FBW aeroplane would behave (ultimately, any aeroplane will settle down at a particular airspeed when in trim and by definition therefore trimming nose up will reduce the airspeed at which the aircraft settles down). However, it is easy for it to get confusing when you have an autothrust system that is adjusting the thrust to maintain a target speed at the same time you are adjusting the pitch attitude because now if you change the pitch but ALSO the thrust to maintain the same airspeed, there is no need to re-trim (again, actually a well-behaved conventional aircraft exhibits similar behaviour but we are used to flying them in manual thrust where we are more aware of the thrust changes or lack of).

As to your first point - that may be related as if you are not in trim I think I recall that PMDG simulated the out of trim forces by reducing elevator authority (so you have to pull more/harder (or indeed push if you are much faster than the trimmed airspeed).

[kevinh 409]

1 hour ago, skelsey said:

As to your first point - that may be related as if you are not in trim I think I recall that PMDG simulated the out of trim forces by reducing elevator authority (so you have to pull more/harder (or indeed push if you are much faster than the trimmed airspeed).

Simon has nailed the likely cause of the problem with this paragraph. In the PMDG 777 you must trim accurately for the speed you are flying at otherwise the handling can feel odd. The more out of trim you are the worse it gets. Personally, I wish PMDG would make this reduction of control authority optional, just as they made the display of trimmed airspeed optional.

Edited September 3, 2018 by kevinh

[sosuflyer 30]

1 hour ago, skelsey said:

Disclaimer: I don't own/fly the 777.

However, from what I understand of the 777 trim: you are trimming for airspeed.

Therefore, if the airspeed isn't changing, you don't need to touch the trim. Now, in your example, if the autothrust is in and you have sufficient excess thrust to maintain the current/selected airspeed, you shouldn't need to touch the trim at all. Just select the new attitude and relax the pressure on the stick and the nose should stay where you want it (basically).

By running the trim in you are selecting a lower trimmed speed. This causes the nose to rise when you relax the pressure.

I think this specifically may be an issue with the way the FBW is replicated in a hardware arrangement where you can't feel the out-of-trim forces; in the real thing in that situation you wouldn't really be pulling against any force so it would feel natural to return the control column to neutral, whereas if the speed was reducing (for example, if you were at a fixed thrust setting) the aircraft would generate a force to be pulling against that you would then trim out.

The thing to remember is that fundamentally there is no mystery to the 777 trim -- the way it is described in the manuals etc is a technical explanation of how Boeing programmed a computer to behave basically how a very well-behaved non-FBW aeroplane would behave (ultimately, any aeroplane will settle down at a particular airspeed when in trim and by definition therefore trimming nose up will reduce the airspeed at which the aircraft settles down). However, it is easy for it to get confusing when you have an autothrust system that is adjusting the thrust to maintain a target speed at the same time you are adjusting the pitch attitude because now if you change the pitch but ALSO the thrust to maintain the same airspeed, there is no need to re-trim (again, actually a well-behaved conventional aircraft exhibits similar behaviour but we are used to flying them in manual thrust where we are more aware of the thrust changes or lack of).

As to your first point - that may be related as if you are not in trim I think I recall that PMDG simulated the out of trim forces by reducing elevator authority (so you have to pull more/harder (or indeed push if you are much faster than the trimmed airspeed).

You missed my point. If I am purposefully under trimmed and maintaining back pressure to hold an attitude, then applying trim in either direction doesn't change anything while holding my controls in place. Only when I release controls do my trim changes come into effect. Which means how am I supposed to know if I have applied enough trim if I can't "feel" the changes I am making (unless I have that blue trim speed option)? If it's designed to act and feel like any other traditional plane, then I should be able to trim out any forces I am applying without having to return the stick to neutral to see if I've applied enough trim or not. Also with the flare, the fbw shouldn't prevent me from being able to flare AT ALL . I doubt routine gear inspections after 600fpm landings were a selling point of the real 777 lol 😂

[skelsey 765]

1 minute ago, kevinh said:

Personally, I wish PMDG would make this reduction of control authority optional, just as they made the display of trimmed airspeed optional.

I'm speculating here but it sounds as though there is *just* a reduction in control authority when actually it should probably be, in effect, a nose-down command to pull against which would make it clear the aircraft is out of trim.

As I say, not being a 777 owner I may be well off the mark here though.

[sosuflyer 30]

3 minutes ago, kevinh said:

Simon has nailed the likely cause of the problem with this paragraph. In the PMDG 777 you must trim accurately for the speed you are flying at otherwise the handling can feel odd. The more out of trim you are the worse it gets. Personally, I wish PMDG would make this reduction of control authority optional, just as they made the display of trimmed airspeed optional.

Yeah, I don't come in for landing out of trim. That's just dumb

[skelsey 765]

5 minutes ago, sosuflyer said:

how am I supposed to know if I have applied enough trim if I can't "feel" the changes I am making (unless I have that blue trim speed option)? If it's designed to act and feel like any other traditional plane, then I should be able to trim out any forces I am applying without having to return the stick to neutral to see if I've applied enough trim or not. Also with the flare, the fbw shouldn't prevent me from being able to flare AT ALL

It's not the FBW. It's how PMDG have simulated the out of trim forces that in the real aeroplane you would be able to feel because the artificial feel unit generates a force to pull against. Clearly this isn't possible with most people's sim hardware, so the 'bodge' if you like is to get you to pull further/harder for the some response and if you are very out of trim you will get no response at all. Not how Boeing designed it but how PMDG have tried to simulate it.

To be clear, when you select the new attitude (say your 10 degrees nose up) has the speed changed at all?

[kevinh 409]

9 minutes ago, skelsey said:

I'm speculating here but it sounds as though there is *just* a reduction in control authority when actually it should probably be, in effect, a nose-down command to pull against which would make it clear the aircraft is out of trim.

As I say, not being a 777 owner I may be well off the mark here though.

Yes, that's what a C*U control law should do, but implementing that would involve another redesign of the FBW. Maybe when/if PMDG simulate the 777X.

[sosuflyer 30]

I don't recall, I was just giving an example of the many times I've tested it to make sure I wasn't crazy. It drives me nuts that this plane doesn't hand fly nicely. If the fbw trim is supposed to feel like other traditional planes (minus trimming out thrust) then just make it that way lol. I feel like pmdg out smarted themselves cause if the elevator trim is supposed to feel like a 737, more or less, then make it feel like a 737 

[kevinh 409]

15 minutes ago, sosuflyer said:

Yeah, I don't come in for landing out of trim. That's just dumb

Dumb may be, but the symptoms you describe (not having pitch authority) are exactly what happens in the PMDG sim if you aren't in trim. To test this try keeping the AP engaged until speed is stabilised at Vref+5 then assess the flare handling when truly in trim. Another possibility is to follow Dan's suggestion to display the FBW trimmed speed and see how well trimmed you actually are.