Sign in to follow this  
asanal

Look at these wings

Recommended Posts

Help AVSIM continue to serve you!
Please donate today!

9 hours ago, asanal said:

PMDG 747 Queen fighting with heavy turbulence.

AuAgNo.jpg

When you say heavy turbulence I guess you’re meaning that you’re using unrealistic active sky turbulence effect settings and forcing it to do so. Of course you’re going to get abnormal results. 

Also, have you disabled turbulence effects on the aircraft in the sim settings?

Share this post


Link to post
Share on other sites

When I first saw this topic, I assumed he was showing off the wings. I didn't think he was reporting a problem, otherwise there would be a lot more information. I could be wrong, though.

Share this post


Link to post
Share on other sites

Chris,

I was showing off how excellent aircraft is PMDG  747 Queen . (I was giving  high Credit to PMDG developer team ) . I have no idea about "active sky turbulence effect" settings or any other companies turbulence effects.

I have REX weather And Active SKY weather engine. I appreciate if you tell me how to determine real turbulence effect settings  and how I can put this setting into Active Sky.

Regards

 

 

 

 

Share this post


Link to post
Share on other sites
57 minutes ago, asanal said:

Chris,

I was showing off how excellent aircraft is PMDG  747 Queen . (I was giving  high Credit to PMDG developer team ) . I have no idea about "active sky turbulence effect" settings or any other companies turbulence effects.

I have REX weather And Active SKY weather engine. I appreciate if you tell me how to determine real turbulence effect settings  and how I can put this setting into Active Sky.

Regards

 

 

 

 

Apologies, when the 747 first came out, there were lots of "that's not how it looks on youtube" complaints. I jumped the gun and assumed this was another one of these posts! My bad!

Share this post


Link to post
Share on other sites

In general, I set all turbulence and gust sliders to about 20%.  I'll still get knocked around a bit but it's not unrealistic. Also, it is worthwhile to  keep the AOA gauge turned on because chop or light to moderate turbulence might not be as apparent as a Hollywood movie but the AOA gauge will be dancing all over the scale.  That's when it's time to turn on the seat belts sign.

Share this post


Link to post
Share on other sites

There has been one question I'd been wondering about ever since PMDG implemented wingflex, and how it possibly contradicts a 777 documentary I saw quite a while ago.  Firstly though, this post is intended to understand the how/why/what/where/when - not suggesting that PMDG got it wrong or anything like that :)

 

In the doco, Boeing was testing a full size 777 wing by physically pulling the tip up until the wing broke.  This was to confirm their computer modelling of how far the wing could bend before the structure of the wing failed (and where along the wing the failure would occur).  The bit I always remember from that doco was that one of the reasons behind the test was the example situation where the airplane is flying straight and level at cruise and during an explosive decompression, the pilot would need to push the stick forward to begin a sudden and rapid decent.  A wire-frame-type computer simulation (Boeing's computer simulation, probably created during design of the 777) of that event showed that as the pilot pitches down suddenly, the wings would actually flex upwards towards it's limits.

 

In the PMDG birds though, pushing the stick forward flexes the wing downwards, and pitching the nose up flexes the wings upwards.  Could anyone enlighten me as to the aerodynamics of sudden pitch changes and the resulting direction of the wingflex as a result?  When suddenly pitching down, why would the wings droop down?  In basic terms, I assume the wing is no longer loaded and the lift vector is much smaller?

 

Thanks,

Subin Jacob.

Share this post


Link to post
Share on other sites
13 minutes ago, Subs said:

The bit I always remember from that doco was that one of the reasons behind the test was the example situation where the airplane is flying straight and level at cruise and during an explosive decompression, the pilot would need to push the stick forward to begin a sudden and rapid decent.  A wire-frame-type computer simulation (Boeing's computer simulation, probably created during design of the 777) of that event showed that as the pilot pitches down suddenly, the wings would actually flex upwards towards it's limits.

Keep in mind that all of this testing was being done in the 90s, on computers likely still running said programs on floppy disks, on computer-aided programs that had yet to be refined to modern standards.

...also: physics exist. It's no secret that a pitch over can induce a red out. This is caused by negative g. Negative g will, by very physical nature, unload a wing (as you, yourself, are also unloaded, technically). Moreover, go look at gliders for a few minutes. Pitching down will unload the wing.

So...you know...

No.

20 minutes ago, Subs said:

Could anyone enlighten me as to the aerodynamics of sudden pitch changes and the resulting direction of the wingflex as a result?  When suddenly pitching down, why would the wings droop down?  In basic terms, I assume the wing is no longer loaded and the lift vector is much smaller?

Because physics, just as you surmised.

  • Upvote 1

Share this post


Link to post
Share on other sites

That documentary was wrong if they said what you said they said about forces during emergency descent. Sounds like something a movie producer would come up with.  Simply stated, it's not logical.  I doubt that there would be more than a slight negative G because in spite of it being an emergency the maneuver is deliberate and takes into account the effect of negative G's on passengers and crew and then there is the need to control airspeed.

A fighter doesn't even do anything suggested by the documentary.  The pilot flips over to an inverted position and pulls positive G's for a rapid descent.

Share this post


Link to post
Share on other sites

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