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

[Airbus Commander 563]

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

Okay, this might be a totally wild off the mark answer, but in the A321, some of us use a technique known as "De-Flaring" where by we actually push forward on the sidestick just before touch down to get a smoother landing.

 

This is due to the fact that if you push forward on the stick in the A321, the MLG actually raises up relative to the pitch axis due to their location relative to the point about which the aircraft is pitching, making for a smoother landing. Am I getting on the right track here, or barking up the wrong tree? Is this an automatic action in the 777? Does de-flaring make for a smoother landing?   :huh:

 

Regards,

Rónán.

[serviceceiling 135]

Has someone bought and read the manual? :lol:

[Ceri Hurlow 17]

Love them photos, How on earth will i avoid admiring the exterior during along haul flight, causing an appcrash, app hang in FSX followed by lots of sobbing etc. Can't wait!

[willultra99 8]

I have bought but not read.  lol

[UAE77W 16]

I have bought but not read. lol

haha lol.

 

It would be weird if someone had written " I read it but didn't bought it ".^^ :blink:

[otts688 1]

I believe the flaperon retracts to decrease AOA as part of the tail strike prevention system found on the 777...tail strikes are definitely chief pilot office visits

 

Tail strikes are costly business, I can't remember what carrier it was but they incurred $12 million dollars in damages in one tailstrike!

 

Erik Otterson

KMSP

[otts688 1]

Well I've talked myself out of that answer as well, it would increase AOA, nuts

[willultra99 8]

Flaprons control roll?

 

Jason is coming in to fast because there is a strong cross wind

 

the 777 is automaticly aligning it's self with the runway by a slideslip or crab angle

[Lek767 37]

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?)

Let's see. If I'd venture an extremely wild guess, I'd say that Jason is going around at the time the screenshot was taken, and the flaperons get out of the way to prevent them from being blown to smithereens by the prodigious amounts of thrust generated by those underslung monsters. Either that, or he has inadvisedly deployed the speedbrakes during short final, causing the flaperons to retract in response (kind-of-source: http://www.airliners.net/aviation-forums/tech_ops/read.main/114281/114287, second post). I do not claim any expertise in these matters, so feel free to ridicule my foolish attempt at informed discourse.

[cdt996 3]

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?)

I think mike alluded to it, but flaperon retraction causes an increase in AOA, which causes an increase in lift as well as an increase in induced drag, slowing the aircraft. As to why the 777 does this, I would guess that any speedbrake would increase v/s too much in a landing flaps config and reducing thrust may produce an excessive spool up time in case of G/A, whereas flaperon retraction would allow the aircraft to maintain glideslope/flightpath.

[blocks_off 5]

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

 

If full flaperon droop has been removed and he's at flaps 25 or flaps 30 - which it looks to be the case - then it's because James is 20kts faster than the approach speed for the current weight?

Carl Beeby

[EGLL77W 1,508]

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.

Luke Pabari: Disorienting Avsim users for 18 years! :-P

[rsrandazzo 6,353]

Gents-

 

Okay- a couple of you are close- but you are getting confused as to whether the airplane is increasing or decreasing pitch by retracting the flaperons...

 

Since Jason is exhibiting an extraordinary case of poor pilot technique, and has exceeded the landing flap Vref by more than 20 knots, the flaperon controller has gone into Landing Attitude Mode. This mode incrementally reduces flaperon droop as the overspeed progresses eventually winding up with the flaperon in the neutral position.

 

This has the effect of shifting the pitch up, which protects the pilot from hitting the nosewheel on the runway due to an excessively flat deck angle as a result of the undesired speed...

 

Key points for you guys who were guessing: This is a completely different function than overspeed protection... This is all about making sure you don't wheelbarrow the airplane down the runway if (like Jason!) you suffer from speed control problems....

[theshack440 22]

Wow that is very impressive! Thank you for the knowledge, Robert. You guys never cease to amaze me in the detail you put into these planes. Wish I could have thanked you in person last weekend!

[EGLL77W 1,508]

@rsrandazzo  :Nail Biting:  :Drooling: