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ArjenVdv

747V3 reverse thrust is wrong

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Hello everyone,

 

 

Yes, I know it's still in beta, but I noticed the reverse thrust in beta videos only goes up to 58% N1.

 

I am getting very hyped over the 747, so I have been watching many 747 videos lately, and came across something by accident. I noticed that the reverse thrust on the real 747 goes up to 95% N1, and not 58%. That is of course a very significant difference.

 

I mentioned this in a thread, and it wasn't believed this is not a real thing. I need documented evidence, which of course, I cannot obtain in any way. But then I realised PMDG use video recordings and photos to help them develop the aircraft, so I don't see why videos would not be proper evidence.

 

So here you go, some video evidence.

 

6:33:

 

 

6:15: (a bit harder to read, but still possible to make out "94" on the EICAS)

 

 

 

 

I cannot imagine PMDG were not aware of this difference, so I assume there must be a very good reason for it. Perhaps a trade off that had to be made to model stopping distance properly? (just speculating here)

 

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Well, it depends on how much reserve you're using. At my airline when there's a fairly long runway (10 - 12,000 ft) in good condition and autobrake 2/3, we can using idle reverse which comes to about 45% N1. We don't always use max reserve due to noise or other reasons.

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isn't the reverse thrust going where you want it? It's not 0 or 1, you know :)

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I understand reverse isn't either 0 or 1, but in FSX people use max reverse thrust in the big majority of cases. They often program their Saitek reverse detent to "F2", so yes, in case of FSX reverse thrust is mostly either 0 or 1. Assuming that the beta guys have been using full reverse thrust, it should have gone up to 95%. If the beta guys had used idle reverse or something in between, then 58% might be correct. But it is extremely uncommon for simmers to be able to do that, because we need a reverse thrust axis for that.

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because we need a reverse thrust axis for that

We don't need an axis for idle reverse thrust. If you push F2 very short you are able to use idle reverse.

 

Kind regards and merry christmas

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but in FSX people use max reverse thrust in the big majority of cases.

 

I always use IDLE reverse, just like in real life, unless wet or contaminated runway, or I have another good reason (e.g. long landing beyond the TDZ).

Even with an axis dedicated to reversers, if you just move the lever slightly you would open the reversers without increasing the thrust (IDLE REV) provided if you correctly set up your offset in FSIUPC.

But yeah... I hope the tech testers made sure that the amount of available REV THR is as per the aircraft FCOM.


Michele Galmozzi

devteam.gif

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We don't need an axis for idle reverse thrust. If you push F2 very short you are able to use idle reverse.

 

Kind regards and merry christmas

I know, but 58% is not idle reverse. If 95% was available, then this means all the beta guys had to be using the EXACT same setting of reverse thrust by accident to end up at 58%, which is next to impossible. This makes me believe the 58% must have been the maximum available reverse thrust. Which is wrong.

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i use a fantastic FSUIPC lua script, which sets a button to toggle reversers at idle. Then if you want, you push throttles forward for more power. If i find the link for the script i'll post it here.

  • Upvote 1

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This makes me believe the 58% must have been the maximum available reverse thrust. Which is wrong.

 

It makes you think that it's wrong.

 

...but you don't have the plane to categorically make the cut and dry 100% certified "this is wrong" observation in the thread title and original post.

 

Guys - quite honestly - this is the absolute worst part of the development cycle. We want to show you the cool stuff, but we also have to weigh what we're wanting to show against all of the YouTube scholars who come out of the wood works.

 

Consider, for a moment, that your reaction to what we're showing has an effect on what we show. People often give us a hard time for not sharing enough at some parts of the dev cycle. Honestly, is there a question as to why? Let's be real, I just posted a current (i.e. incomplete) list of liveries in another thread and it nearly instantly turned into us "leaving out" all kinds of things. I then got PMs about how people are mad that X, Y, and Z "won't be included."

 

Can we put the hyperbolics and YouTube diplomas away for a bit, please? We have an entire team full of people who have a plastic trump card called a type rating.

  • Upvote 25

Kyle Rodgers

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Kyle,

 

I never meant to negatively attack PMDG. I am not that type of person who sends you PMs moaning about what is wrong and what is right. My only intention is inform my observations and ask why the footage is different from the footage of the real plane. And yes, if I think it is incorrect, I will say that too. This should not be a reason to be reluctant to show beta footage at all. People are going to ask questions, and give feedback, that's inevitable.

 

But for the last few years PMDG seem to have become more like "religion" or something. Even the forum members don't accept any constructive critisism to PMDG, anymore. They all assume that the almighty PMDG is always right. We shouldn't ask questions, and should take things as they are. 

 

Don't get me wrong here again, you deserved that amount of trust from the community because the quality has always been great. I love your products and you are my number 1 favourite developer (together with FSLabs), but I just don't think there is any company out there that can do everything flawlessly. And you know what? That is perfectly fine, as long as the company and its members don't feel offended about some critisism. If I am wrong, that is fine. I am completely prepared to admit my mistake. But instead of everybody waving things off as always (because PMDG cannot be wrong because they are PMDG), maybe someone can come up with an answer to my question, why there is such a big difference. I am sure proving me wrong should be a piece of cake. It litterally takes 1 minute to fire up FSX, engage reverse thrust in the 747V3 and show us a screenshot of the EICAS, and show that there is 95% available.

 

Lastly, I am no pilot, nor am I an engineer (yet). But I am a third year Aerospace Engineering student, so it's not like I am completely unfamiliar with engine dynamics. So calling me a YouTube scholar, is a bit unfair. Of course, YouTube is not always reliable, but some simple rational thinking brought me to the conclusion that there is no 95% of reverse thrust available in the 747V3 (I am not going to explain again how I came to that conclusion).

 

If I am wrong, fine, but if I am right, I really hope you will consider this as constructive critisism, and hopefully do something with it. My only intention is to assist by making an observation.

  • Upvote 11

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But Arjen... They are showing the beta ...not asking for feedback..feedback will be much more important when you have the aircraft in hand..

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I'll trust PMDG

And this is what I meant with "PMDG has become like a religion." This is what is wrong with the PMDG community. People are so much in heaven with their products that any critisism is completely unheard of. Such a mentality is very bad for product quality in general...

  • Upvote 9

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And this is what I meant with "PMDG has become like a religion." This is what is wrong with the PMDG community. People are so much in heaven with their products that any critisism is completely unheard of. Such a mentality is very bad for product quality in general...

What I meant was I'll trust the people who work on these things, fly these things and have studied these things in detail. I'm impressed, well done on being an Aerospace "student", but until you are qualified in some form on a 747, I'll trust the people that are.


David Porrett

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