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rsrandazzo

06MAY13 - PMDG 777 External Model Preview #1 of 2

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Robert, just one quick question. It's not a greatly important effect, but will heat blur from the engine exhausts be a feature of the 777 product by any chance? You've gotta admit it would look cool, if it can be done...

 

 

I concur! Heat blur would be awesome and very, very  realistic!


Edmundo Azevedo

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WHY it is doing what it is doing...  B)    (Load relief is not a factor in this case...)

To avoid constant small changes in thrust it adds and removes a small bit of flap to alter the drag if the speed changes above or below selected speed.  ^_^  :wink:  B)

 

Regards,

Ró.


Rónán O Cadhain.

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I concur! Heat blur would be awesome and very, very  realistic!

 

 

For what I read, Can't be done on FSX

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What a fantastic thing to wake up to this morning, thank you for the updates Capt.

 

The flaperons are lowering to increase drag and lift allowing the plane to maintain the same AOA and thrust on approach?

 

Ró beat me to it. I think our answers are pretty close though.

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Robert, just one quick question. It's not a greatly important effect, but will heat blur from the engine exhausts be a feature of the 777 product by any chance? You've gotta admit it would look cool, if it can be done...

 

 

I concur! Heat blur would be awesome and very, very  realistic!

 

 

For what I read, Can't be done on FSX

 

I'm with Matias.  I don't think it can be done in FSX.  Even if it could, it's not as obnoxiously obvious as a lot of people think it is.  It depends on lighting, air temp, and a bunch of other factors as to how obvious it really looks.  Most days I was out on the ramp, I couldn't see a thing.  The only way you knew an engine was on was by looking at it, or noting that a beacon was on.

 

Interestingly enough, if you try to Google "aircraft heat blur/shimmer," most of the pictures are from Flight Sim, or generic ground heat shimmer.


Kyle Rodgers

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Rob,

 

One more try -- If I'm wrong I'm going back to the default 777-300 in FS9!

 

The aircraft is too fast, which means it is too nose down and it is descending at too fast a vertical speed, assuming a normal three degree glideslope. The flaperons retract, reducing lift aft of the wing (and aft of the center of pitch rotation), thus pushing the nose up, to both produce a proper flare landing attitude and reduce vertical speed. The flaperon retraction and flare didn't slow the aircraft much -- hence the glowing brake pads.

 

BTW, thanks to Machine2035 for spotting the flaperon retraction in the first place, and "Flaperons for Dummies" is hilarious!

 

Thanks,

 

Mike


 

                    bUmq4nJ.jpg?2

 

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What a fantastic thing to wake up to this morning, thank you for the updates Capt.

 

The flaperons are lowering to increase drag and lift allowing the plane to maintain the same AOA and thrust on approach?

 

Ró beat me to it. I think our answers are pretty close though.

 

John & Ró

 

You guys are close- but not quite there... 


Robert S. Randazzo coolcap.gif

PLEASE NOTE THAT PMDG HAS DEPARTED AVSIM

You can find us at:  http://forum.pmdg.com

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Oooh mike- so close...  yet so far...  

 

You are in the right general area- but you need to think through your answer a bit more.

 

Is it to do with the G/S Capture? If the aircraft rises a certain amount above the G/S without initiating a go-around the system compensates to try and maintain the decent rate? 

 

Chris

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Rob,

 

One more try -- If I'm wrong I'm going back to the default 777-300 in FS9!

 

The aircraft is too fast, which means it is too nose down and it is descending at too fast a vertical speed, assuming a normal three degree glideslope. The flaperons retract, reducing lift aft of the wing (and aft of the center of pitch rotation), thus pushing the nose up, to both produce a proper flare landing attitude and reduce vertical speed. The flaperon retraction and flare didn't slow the aircraft much -- hence the glowing brake pads.

 

BTW, thanks to Machine2035 for spotting the flaperon retraction in the first place, and "Flaperons for Dummies" is hilarious!

 

Thanks,

 

Mike

Okay guys- Mike is on it... but WHY... WHY is the airplane doing this?

 

("This" being- retracting the flaperon to shift the center of lift and increase the AoA?)

 

Come on Mike- I know you got it... LOL

 

And the glowing brakes was a different flight- unrelated to this... Although if you landed fast enough to overheat the brakes- then you definitely saw this mode of the flaperon control logic... LOL


Robert S. Randazzo coolcap.gif

PLEASE NOTE THAT PMDG HAS DEPARTED AVSIM

You can find us at:  http://forum.pmdg.com

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" but WHY... WHY is the airplane doing this?"

 

 

 

Pilot Error ;-) 

 

Chris

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Okay guys- Mike is on it... but WHY... WHY is the airplane doing this?

 

("This" being- retracting the flaperon to shift the center of lift and increase the AoA?)

 

Come on Mike- I know you got it... LOL

 

And the glowing brakes was a different flight- unrelated to this... Although if you landed fast enough to overheat the brakes- then you definitely saw this mode of the flaperon control logic... LOL

I could be wrong, but I have a hunch this is part of th Fly-By-Wire protection.

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("This" being- retracting the flaperon to shift the center of lift and increase the AoA?)

OK, one more try: Strong nose up exposes the underside of the wings making them act like large flat airbrakes. It also reduces lift -- a good thing just before touching down too fast -- by increasing the AOA (possibly also reducing lift by disrupting airflow over the front slats).

 

Mike


 

                    bUmq4nJ.jpg?2

 

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Slightly fast on the approach so removes some flap to reduce lift and help get those wheels stuck on the ground and improve the braking action? I'm at a loss apart from that...  :mellow:  :huh:  :blink:

 

*The 747 retracts slats when reverse is out right? Something similar to that...*

 

Or, maybe it thinks he's going to go-around and is getting the aircraft into a low drag configuration? 

 

Regards,

Rónán.


Rónán O Cadhain.

sig_FSLBetaTester.jpg

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@rsrandazzo I'm sure the Flaperons essentially stops working as a flap past Flap 25-30 to provide more smoothness on the controls and better aileron control on approach to landing? Also the fact the Flaperons are there to assist the Flaps, so past 25 surely the Flaperons would cause more drag than lift being level with flap 25-30; therefore it being straight and essentially back to a normal aileron like you'd see on the 747 and gains a little more lift that could be very useful - well, when is lift not usefu!l (Rob thinks about the wonderful times in Ground Effect!) The Flaperons should then normally droops back when speedbrakes are put down at around 15 degrees after landing.

 

Not sure if you're looking for something really detailed, so I could be completely wrong - either way it seems you've modelled the Flaperons system perfecto :-P

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Not sure if you're looking for something really detailed, so I could be completely wrong - either way it seems you've modelled the Flaperons system perfecto :-P

 

Your change in avatar and signature image is throwing me off!  I didn't even realize it was you who posted that until I looked at the user name.


Kyle Rodgers

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