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Has anyone gotten auto step climbs to work since upgrading to SP1?

My ND shows S/C and VNAV approaches the step point but it seems to never get there. I seem to be perpetually at least 1 nm from start climb.

On my sim, the engines are 100% spooled within seconds of applying full throttle. If your engines are still spooling at V1, there is definitely something wrong with your configuration.

A system with 16GB of RAM doesn't even need virtual memory though, I'm not sure how this makes sense... The entirety of FSX's VAS footprint can be placed directly into system RAM unless your system is somehow using 12+GB of RAM for other tasks while using FSX (which seems virtually impossible to me).

 Windows does pre-cleaning (http://en.wikipedia.org/wiki/Paging#Pre-cleaning). Basically the OS will selectively write pages out to disk while keeping it in memory also so that when memory pressure goes up, it will be able immediately overwrite the in-memory pages.

The resizing process requires that the virtual addresses for everything to be recalculated so it could potentially freeze FSX.

Not saying that this is what is happening here, but at least theoretically it could be an explanation.

Not to be myself, but to be honest, all of the "me too" is completely worthless without steps to reproduce or screenshots.  If it can't be reproduced, it can't be found; and if it can't be found, it can't be fixed.

No, speaking as a software developer myself, it's largely helpful if you know more than one person is having a problem. If more than one person reports such a problem, we can now be sure that message exists and isn't just the reporting person's imagination. 

A dev can now easily grep for "Vertical Stabilizer Configuration" in their source code and program logic and closely examine the behavior for himself with a debugger, perhaps even in real time.

So the 747-8 is a failure? And if so, is this the end of the road for the 747?

It's hardly a failure, although it's getting stiff competition from below by the A350/777 and from above by the A380. One could surmise though that it was designed to prevent the A380 from completely dominating the VLA market, although that is quite a Pyrrhic victory.

I doubt we'll ever see another iteration of the 747 in the future though.

The above picture has got me thinking.

The similarity in EGT and N2 despite the difference in N1 when the EEC is in hard alternate mode seems to suggest that all that is going on in the background maybe that the sim is basically just indicating +2% to N1 gauges.

I'll do more tests after my next VA flight is done.

Could the manual mean the range where temperature is 40-50C? Since the EEC in normal mode would wind the N1 down above ISA+15 to maintain the T/O EGT at roughly around or below the redline (ie 98% N1 for 50C at sea level)  while in hard alternate the EEC should maintain a higher N1 value (ie matbe around 102.7% N1 ).

I don't know if I parsed what you are saying correctly. Are you saying that at 50C, the engines N1 would be limited to 102.7% N1 because of EGT limit?

The engines don't reach close to 102.7% N1 (see picture below). Also note that the similarity of the EGT.

The sim here is also weird with respect to the EGT limits. If you fudge around with pressing F4 to try the override the EEC, you can see that the whole dial turns red at 110.5% N1 and 121% N2 as expected from the engine's type certificate. However, the EGT rated for this engine is 1090C (5 minute T/O), or 1050C (Max Cont). The sim seems to trip at 980C instead.

Another interesting thing to note is that the EGT of both engines are basically the same, despite the difference in N1 %.

Edit: Wrong picture. I'll upload the correct one in a minute.

Edit2: Correct picture uploaded.

It's a limitation of FSX texture loading. Nothing you can really do about it.

Is it possible these messages are occurring in states derived from the "777 Cold & Dark" panel state?  Seems to me I was getting them earlier but when I made sure I was not using a panel state derived from the C & D one, known to have bugs, it stopped happening.

 

Mike

Not in my case. I use the default panel state.

Still dont get it that N1 redline protection and overspeed protection are the same thing do you?

Still don't get that 90% N1 isn't anywhere near redline do you?

After I do some digging in AMM of B737NG (since B777 AMM doesn't really give me any thing) I finally found something.

"In the hard alternate mode, the EEC uses static pressure (P0) to

get an assumed Mach number. To make sure the airplane will

have enough thrust for satisfactory airplane performance in all

conditions, the EEC assumes the outside air temperature with

the highest thrust requirement. In this mode, large maximum

thrust rating exceedances are possible during hot day

conditions. This can cause EGT exceedances during hot day

conditions"

This however does not correspond to what PMDG has programmed into the sim then, because in hot day conditions, again you only get small thrust exceedance (if we can we say it is in exceedance).

Do we know if alternate mode EEC calculated limit is actually over boost? Could it be possible that simply the normal mode EEC calculations have a small buffer built in?

Anyways I have opened ticket with PMDG to see what the actual behavior of the plane is supposed to be, although I doubt we'll actually get a technical answer.

I don't know what you mean by "engine rating", but the picture below shows everything you want I think. It's -30C SAT, sea level, 29.92 in, EEC in hard alternate. As you can see, it can only command slightly above yellow line, but it's nowhere close to even 100% N1.

Is that in Normal mode or soft alternate mode or hard alternate mode?

All 3. (If you mean soft alternate as failing via failures options)

You wanna know the difference between them and I?  I never said I could and therefore people never would expect it from me, nor have a taken any money to do so.  So the difference is went you say you can do something and fail at it (and dose so badly) people have a right to say you failed.  Also when even them themselves admit they dropped the ball.  Let also remind you most games the online works from day one with only slight adjustments needed.  Not huge down-times.  Its worth saying also they got over two weeks to see how many copies sold and adjust the network needs to meet the known likely demand from sales numbers, this is why I said it was a fail really.  Most games have only estimates of coming sales and get online infrastructure needs pretty much right.

 

I work as a networking administration and security consultant.  I'd like to work on a project like this, because I'd tell them with their budgets and known information we can get this done right the first time every time.  My skill set is not really designing or even working on a network anymore (but can and do do it).  More-so to meet, talk, look and find a solution then communicate that downstream to techs.  But I can tell you some of my past employers that networks have demand and likely security concerns over huge networks and never fail to work like Lockheed Martin, Philip Morris, and the Fifth Federal Reserve Bank of Richmond, VA.  I always ended my contracts on high remarks.  Why? Because I never said I was going to do something for these companies and organizations and not do it even when given less known variables.

Lockheed Martin, Philip Morris, and Fifth Federal Reserve Bank of Richmond VA have vastly different budgets and peak network load requirements than a company like Rockstar or EA or Blizzard.

Look at WoW: MoP, Simcity Online, or Final Fantasy XIV for recent examples. These games are all done by major publishers that have established credentials and are all hugely popular games. For the first 12-24 hours, all of these games were unplayable. The fact of the matter is that rational companies won't drop 100 million dollars on servers to handle release date traffic and then only utilize 1% of that power a week later.

What was your speed tape indicating?

Are you looking for VNAV FMC button -> Next Page (until you hit DES), and then SPD TRANS?

Probably out of your price range, but it was definitely a no brainer for me since I'm a professional programmer.

Retina Macbook Pro (2012). 2.6 GHz, 8 GB RAM, Nvidia GT650M.

If I run it at "normal" laptop resolution settings (i.e 1440x900), framerates are as good as they can get. (25 in most major 3rd party scenery airports). If you don't mind lower frames (~15 FPS), 2880x1800 is simply gorgeous.

How about you being less challenging of other people and actually listen to what they say? Oh, and how about you start signing your posts? You know, how we are all supposed to do in this forum. It helps keep things civil. Leaving aside your conclusions (right or wrong) about how the real GE90 should behave, you refuse to accept the most obvious explanation of the 777X's behaviour (FSX engine simulation model limitations).

 

Nothing in CessnaPilot's explanation contradicts anything Rob and I have been saying. He's just explaining the difference between limiting thrust and governing RPM. I wouldn't disagree with a word of it.

 

Without a full set of engine and FADEC data from GE I can't possibly answer your question. The FCOM certainly doesn't answer it. However I can suggest that the PMDG model might not react exactly as the real engine does in very cold or very hot temperatures. One thing I can say is that on a cold day the air is more dense, so for the same N1 the engine will produce much more thrust. Another thing you should understand is that alternate mode is not off.  The EEC is still running, it's just in a degraded mode using more basic information. So it's quite possible that full throttle does not produce red line N1.

 

Whether or not the real engine will red line in alternate mode is not relevant if FSX limitations have forced PMDG to compromise on this. Please bear in mind PMDG got a lot of 777 information from access to a full flight simulator, so it's highly likely they tried operating the sim's engines in ALTN mode to see what happens.

 

I am not willing to spend time debating this with you when you clearly aren't interested in some of the points made to you. You can't be bothered to follow simple forum rules. I can only suggest, very strongly, that you open a support ticket with PMDG for this "bug" and get the answer direct from them. I cannot speak for them, I can only tell you what they told me on a related matter. 

No, you and others just don't seem to accept that my explanation maybe correct. 

I'd be happy to discuss any counter-arguments as to why my theory "thrust overboost limitation is active in alternate EEC mode" is wrong, which was what I was trying to do with 777simmer.

However, 777simmer keeps moving the goal-posts. Initially suggested an "overboost limit", and then to "N1 redline protection", and now "overspeed protection", all of which are distinct systems. Which is it?

You just seem to keep specially plead "FSX limitations" and declare it as the simplest explanation, when it is not an explanation at all. It is a complete copout. You are saying "I dont know why the sim doesn't act correctly, I'll just blame it on FSX limitations". A real explanation would be if you characterized the FSX behavior as it pertains to the throttle, created a modeled for this behavior and then provided a reproducible result that exercises your model.

The throttle scheduling maxing out at less than N1 redline limit is a good idea, except that it seems to go against Boeing philsophy, and the observation is that in the PMDG777 at least, the scheduling shouldn't change because there's no way the engine can even know the atmospheric conditions it is operating in.

I think you mean; and some are having the exact same problems...

 

I'm sure most T7/NGX users are flying high without problems.

 

I also think its funny how people overly try to use dumb pictures like you did.  A few users have a problem and you want to call it a triple facepalm fail.  Meanwhile 1000's of hours have been flown by 1000's of users (almost 250 here on 777 myself) without a problems.  Yeah so, sounds more like a local problem or real triple facepalm fail on your part or setup.  

 

An example of a triple facepalm fail would be GTA 5 online, they pulled in 1 billion+ dollars, yet on the day of online release (Oct 1st) can't get 99% of users online for over 24 hours.   

That's not a triple facepalm. I'd like to see you design a system that can handle that many users on release day.

I too am seeing this however I am using AS2012 during my flights so it is possible the winds have changed by the time I get to a point. Keep meaning to try with a set weather setup. Sounds like you are and still seeing it.

 

Perhaps I will try it tomorrow and make certain but it is a little annoying I must say.

What about trying a long flight with absolutely no weather?

I experience the same thing as OP. ILS autoland. So the throttles already go to idle in the flare 15-20 feet above ground.

It doesn't seem to want to go to REV immediately. I have to hold down F2 for a second or two before the amber REV is annunciated on the EICAS. No FSUIPC.

First I would like to introduce a term rated thrust 

 

Rated Thrust is the amount of thrust that manufacturer guarantee that this engine could produce untill ISA+15. (30C at Sea level). In order to produce to same amount of thrust at ISA+15 (30C) compare to ISA(15C) the engine must throttle up from maybe 100% N1 to 106% to compensate for less mass airflow pass through engine and this is what actually happened in alternated mode. 

 

In alternate mode the EEC lost its air data input and hence unable to calculate the amount of N1 it require to achieve the rated thrust. So in alternate mode the EEC assume that you operate at the edge of certify envelope (around ISA+15). Hence for the same throttle position, the EEC in alternate mode will automatically increase the N1 by couple percent in which if you fly in ISA lower than +15 you will have an "Overboost" due to the increase in air density.

 

However, the physical limit of N1 or N2 (ie due to the bearing load as Rob point out) always limited in either normal or alternate mode by governor in EEC control logic and shall never ever be over that value.

Yet another good point. OVERSPEED PROTECTION with EEC failed means that there is no input about the air density, temperature, etc. Thus, it shouldn't change with regards to air temperature. Meanwhile, in the PMDG if you set the outside air temperature really cold, (say -30C) you can't even command 90% N1. How do you explain that 777simmer and kevinh?

If you have no speed restrictions on your VNAV path then this is correct - you'll see nothing but T/C and E/D.

Could you clarify this a little bit more please? Does this mean if I program something into the SPD RESTR field in the VNAV DES page, this little green circles will show up? Because I could not get that to work either.

The throttle schedules an N1. It's a moveable governor setting if you like. Even if the EEC limits are off, the scheduled RPM will still have a maximum N1. So the engine is still governed, but not limited.

 

The 6,200 rpm in your car is the user's red line, a safe limit. You can be sure the engine can safely run faster than that, possibly 7,000 rpm or more. A FADEC control on your Camry might schedule a demanded engine rpm, increasing linearly up to 6200 rpm at full throttle. But to be able to achieve 6200 rpm at that position in all conditions, the "non limited" engine controller must be able to exceed 6200 rpm at full throttle. So if you set 6200 rpm and somehow failed the limiter the engine might now run at 6,400 rpm (for the sake of argument). This is still not be anywhere near the real red line of the engine.

Yes, but the red-line on the aircraft engines, is also a "safe user limit". It's tested to run 60 hours at 110.5%N1. No one even really knows (except GE and Boeing maybe) how fast you can run the N1 fan above 110.5% N1 for how long before it actually disintegrates (and likely there is some distribution of failure points across individual engines...)

You can be sure that the GE90-115B N1 fan doesn't disintegrate when you hit exactly 110.5% N1, it still takes at least 10 runs of 6 hours (per the certification test). Obviously they dont want to rate it that high and build in some safety margins so the engines aren't run at triple redline on every flight, but why not make this available to pilots in an "oh crap" situation that they can select it if they want. Doesn't this go against the Boeing design philosophy that the pilots can override the computers if they deem that is the prudent course to do so?

Yes but how do we know how much this OVERSPEED PROTECTION limits the RPM?

Thats why I asked how much you would like...103...104...105...?

Not to annoy you but because we dont know if overspeed prtection in the real aircraft limit the RPM to 110.49999% or to 105 or 102. I have no data on that and I dont think my Captain on tomorrows flight back home will let me try to see how far I can go with EEC off. Sorry :-)

 

Ps I noticed your toyota has a hypothetical governor as well ;-)

I just mention Governor as a possible item that could fail and result in RPMs going crazy!

Normally your RPM are not supposed to go up to redline in either EEC mode.

Nothing hypothetical about it.

Had it once on a 737 simcheck on take off. TOGA...full thrust and right N1 went through the roof. Airplane veered to the left so I closed the thrust lever. Right N1 still through the roof (Governor broke so no response to thrust level position) so we had to shut down the fuel control lever quickly. Ended up in the grass anyway though.

Good lesson!

It doesn't make sense to have the OVERSPEED PROTECTION at anything less than 110.5% N1. The engines can do (as in a batch of engines have physically been run) 10 runs of 6 hours at 110.5% N1 (as well as max N2 and EGT) and show no signs of distress. They sure aren't going to blow up right at 110.5% N1.

Because there IS. It is called OVERSPEED PROTECTION or N1 REDLINE protection and has nothing to do with the amber thrust limit protection line.

N1 REDLINE is 110.5% N1!!! Even in your OWN examples, you are nowhere close to 110.5% N1. Actually in one of them you aren't even over 100% N1.

Compare it to a car if you want.

(purely hypothetical I know cars dont have PS limit protection)

 

Take a car with max 150PS. More than 150PS does damage to the engine, the bearings or whatever.

That is where your Thrust Limit Protection comes in. It prevents you from producing more than 150PS even with the peddal floored.

That is what the EEC can only do in normal mode.

 

Then there is the RPM. The engine redlines for example at 8000RPM.

Beyond that you again do damage to the engine.

Not because of 150PS but purely centrifugal forces blowing the engine apart.

That is where N1 Redline protection comes in.

This EEC prtection works in normal as well as Alternate mode.

Ok, let's take my Toyota Camry for example. The red-line on my tachometer is 6200RPM. The governor kicks in EXACTLY 6200 RPM (it's computer controlled). I can't get my engine above 6200 RPM. Not 5500 RPM.