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Arnason

Climg performance 777

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The climb performance (vertical speed) is very bad on you Prepar v4 for the 777.

It was impossible for me to reach FL 430 from BIKF-RJAA

The stall warning was constantly on.

This needs to be fixed by you´re coders!

Thank you

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Which variant were you flying, and most important, what was the aircraft weight? Just because the 777 has a maximum ceiling of FL430 does not mean that it can always reach that altitude. It can only happen when most of the fuel has been burned, and even then, it may not be possible if the aircraft is heavily loaded. The 777-300ER in particular could almost never teach that altitude - it would have to be almost completely empty. The aircraft has to weigh less than 380,000 pounds (176 tons) to reach FL430

Were you using real world weather, and if so, what was the outside temperature? 

The fact that the stall warning was on should have been a clue that you were trying to push the airplane beyond its maximum altitude for the current weight and outside air temperature.

There is nothing wrong with the coding of the airplane, I have had the PMDG 777-200LR up to FL430 with no problems. I've never tried going that high in the 777-300ER because, as I said, that version would have to have almost no fuel passengers or cargo to reach the maximum altitude.

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Considering that the plane has been out for a while now and not a single person has reported this, you really need to have a look at how you're flying the plane and have a look at performance charts. There is not a single plane out there that can carry passengers and fuel for a flight that long and still be able to reach that altitude right away, if at all. If you look at the VNAV page on the FMC, on the cruise page (I think, anyway, I know this was the case on the 747), it should tell you the optimum cruise altitude and the maximum cruise altitude based on your present weight. You will find that you were most likely trying to fly above the maximum altitude listed.

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20 hours ago, Arnason said:

This needs to be fixed by you´re coders!

If you're attempting to fly that distance, I'm going to press back here. What needs to shift is not the code, but your understanding of how aircraft operate, their performance, and how what you are seeing is a result of how realistically the aircraft has been modeled. Just because you do not expect it, does not make it a bug.

While this is of a 748, you can see that it makes two distinct changes (climbs) in altitude:
http://flightaware.com/live/flight/DLH419/history/20170915/2205Z/KIAD/EDDF/tracklog

This is because the aircraft will not be able to climb any higher until the aircraft is at a weight that the thrust can accommodate for that altitude. If you have a question, please don't hesitate to ask. Please be mindful about asserting things are bugs when you do not have the backing for that assertion.

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Sir.

I appreciate your long distance answer. I am fully aware of how aircraft of all sizes operate as a ATPL holder. 

You claim : what you are seeing is a result of how realistically the aircraft has been modeled.

You do not ask about payload or fuel that I loadet for this flight. I would expect a tripple 7 to climb more than 500 feet per minute at or above FL1000 at or above 250 IAS.

If not the plane should be groundet.

Please be mindful about asserting things as lack of knowledge on my behalf when you do not have the backing for that assertion.

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9 minutes ago, Arnason said:

Sir.

I appreciate your long distance answer. I am fully aware of how aircraft of all sizes operate as a ATPL holder. 

You claim : what you are seeing is a result of how realistically the aircraft has been modeled.

You do not ask about payload or fuel that I loadet for this flight. I would expect a tripple 7 to climb more than 500 feet per minute at or above FL1000 at or above 250 IAS.

If not the plane should be groundet.

Please be mindful about asserting things as lack of knowledge on my behalf when you do not have the backing for that assertion.

Did  you not  read  post 2  By  Jim  and  since  you  didn't  reply  to  his  questions,   than why  would  kyle  post  the  same  questions  again  and  since  no  one  has  posted  this  issue  one  would  assume  its  only  specific  to your  set  up.  Pmdg  requires  your  full name   to each of  your  posts  otherwise  you run the risk  of  the posts  being  deleted

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Is this forum not run by good manners rules. This is the most insulting reply to a post I´ve ever read and I´ve come across a lot in the simworld. 

I can not see that you display you´re full name but a silly nick name. For you´re FMC my full name is stated in my profile. 

Goodnight!

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1 hour ago, Arnason said:

Is this forum not run by good manners rules. This is the most insulting reply to a post I´ve ever read and I´ve come across a lot in the simworld. 

I can not see that you display you´re full name but a silly nick name. For you´re FMC my full name is stated in my profile. 

Goodnight!

goodnight ,  if  you look closely  i  always  had  my full name  to my  posts,  and  you  still yet  to  answer   Jim's  question,  so guess   that  you  don't  want  the issue  resolved  than

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This guy is a troll right? FL1000? 100,000ft? And then people try to explain things and he says their being rude?  Whaaaaaaaaat

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OK, for the benefit of trying to help - please tell us the fuel and payload you were using for the flight from Keflavik to Narita. That way, more knowledgeable people on this forum may be able to help - I'm just a layman. Whilst I have respect for your ATPL licence, there are other pilots who visit AVSIM, not to mention aeronautical engineers.

Which type(s) do you fly?

I also suspect that English is not your first language (you write it very well!!). Some of the things said may translate as being rude, but in fact they are not meant to be. :blush:

With regard to the full name, it is implied that the name should be displayed on your posts and not in your profile. The most usual way to do this is by placing it in your signature area which appears at the bottom of each post. This is PMDG's rule for this part of the forum. Their product, their rules.

We should be able to achieve an amicable solution :cool:

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On 9/17/2017 at 2:51 AM, Arnason said:

 I would expect a tripple 7 to climb more than 500 feet per minute at or above FL1000 at or above 250 IAS.

I should certainly like to see the Boeing Triple Seven which could make it up to FL1000, that's nearly nineteen miles straight up, I think you might manage it in a MiG-25, but that's about it.

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The 777 is a beast when it comes to takeoff capabilites, but that does not mean it can climb directly to cruise altitude...by any means.

The flight I dispatch (KIAH-RJAA) has AT LEAST 4 step climbs before reaching final cruise (FL380/390).
And usually, the final step climb is two hours from TOD. There are weather variables that you must also consider, headwinds, temperature, etc...

USUALLY, a good step climb begins at FL 300/310/320 and as your fuel decreases, you go up from there. It is a simple concept but people think because FMC says yes, the answer should also be yes. A good pilot will give himself safety buffers. I personally do not like high angles of attack at cruise, so I always go with best performance, not the convenient option...you will find many in real life who also do this.

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I recall that I read somewhere about navigation that in real life no airliner/captain goes higher then FL390 with passengers onboard. Only maybe higher with only crew onboard for just moving
the plane to some other airport far away.

Maybe I recall wrong?

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1 hour ago, PerWel said:

I recall that I read somewhere about navigation that in real life no airliner/captain goes higher then FL390 with passengers onboard. Only maybe higher with only crew onboard for just moving
the plane to some other airport far away.

Maybe I recall wrong?

In 2004, I was on board an American 777 that went up to flight level 410 near the end of the flight. I was surprised at seeing that on the screen, as I hadn't been on a flight that went up that high before.

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On ‎9‎/‎16‎/‎2017 at 9:51 PM, Arnason said:

I am fully aware of how aircraft of all sizes operate as a ATPL holder. 

I'm going to press back here, again.

An ATPL holder should volunteer the evidence behind their assertion ahead of time to prove their knowledge without resting on a qualification. A simple qualification. As an ATPL holder, I'm sure you've come across other pilots who don't know what they're talking about.

On ‎9‎/‎16‎/‎2017 at 9:51 PM, Arnason said:

You do not ask about payload or fuel that I loadet for this flight. I would expect a tripple 7 to climb more than 500 feet per minute at or above FL1000 at or above 250 IAS.

If not the plane should be groundet.

This should not have to be requested. If you're going to assert something is a bug, then evidence should be provided.

I would expect that the aircraft would never reach FL1000.

On ‎9‎/‎16‎/‎2017 at 9:51 PM, Arnason said:

Please be mindful about asserting things as lack of knowledge on my behalf when you do not have the backing for that assertion.

I never said you lacked knowledge. I said you needed to shift your understanding of how the aircraft operates (given the knowledge available to me at the time, which did not suggest you actually knew how aircraft operated - I can't assume everyone here is an ATPL...nothing would ever get solved), and I also finished by saying that you provided no true evidence that the aircraft was behaving improperly. You simply stated it.

If I walked into Cessna's headquarters and told them that they designed their C172 improperly because it couldn't reach 9000 feet without stalling, and left it at that, I shouldn't be surprised if someone didn't simply say "you know, you're absolutely right." Rather, I shouldn't be surprised if they just said "okay," and showed me the door.

Now, if I walked in and said "hey, I was flying the other day at X weight, and it was Y temperature, and Z pressure; everything on this chart says I should've been able to reach 9000 feet without issue, but I wasn't able to," then I'd likely get a response more direct to the actual issue. I thought there was an issue, and I brought evidence to support that thought. To any ATPL holder, familiarity with this sort of evidence should not at all be foreign, much like most of us already default to providing a reason when we say 'unable' to ATC if they ask us to do something (like climb higher than the aircraft is capable).

 

 

Now, if you meant FL100 earlier, and that the aircraft had poor performance all the way down at FL100 (and had stated that from the outset), then I could have been aware of the issue a little bit better to suggest that - if you're using FSUIPC - you should remove the FSUIPC.ini file out of the modules folder temporarily to see the result. If you're just going to come immediately with "you're wrong" without any justification or evidence, though, don't be surprised if you get pushback.

1 hour ago, PerWel said:

I recall that I read somewhere about navigation that in real life no airliner/captain goes higher then FL390 with passengers onboard. Only maybe higher with only crew onboard for just moving
the plane to some other airport far away.

Maybe I recall wrong?

Maybe one particular airline for some reason, but I'm not sure where you would've seen this as a blanket statement as a hard rule. Perhaps the person misspoke, or misinterpreted what someone else said. My bet is that someone said that to mean "given the weight of passengers and our normal segment link, we rarely get above FL390 as a matter of OPT ALT."

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