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ApacheHunter

Red boxes around N1 values

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I'm currently in the descent phase of my flight from Washington Dulles Intl. to Amsterdam Airport Schiphol. During the climb phase I noticed red boxes had appeared around the N1 values on the upper EICAS display. They've been there troughout the flight and still are there. What causes these red boxes and how can I get rid of them?


With kind regards,

Kevin Schepers

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The only time I'v seen this is in the MD11 and 747 products, when I haven't used Autothrottle/TOGA for takeoff and accidently missed the click and jammed the (hardware) throttle forward to the null zone I have up top. That tends to give an N1% value of over 100% (116% is the best I've seen in the 747 yeehaw) This is a higher power setting than the engines can handle for any significant time, and the red boxes will come on and never go away.

 

In real life this happens too, and the only way to reset the red boxes is to get an engineer to do an engine inspection and reset the system. Red box is there so it's pretty obvious there's something that went on that needs checking out, and the next crew to get the aircraft will notice too, even if it wasn't written up in the aircraft logbook.

 

In FS, I think this can also happen when the weather engine injects bad weather too. (like the infamous +45°C at FL380 that FSinn likes to inject)

 

So that's the 2 reasons I can think of that made this happen:

1: Autothrottle disconnected and throttles manually pushed up to/past max power for a long while (more than 60 seconds)

2: Weather was ridiculously and unrealistically hot in the ISA+90°C range.

 

There might be a possibility of no derate takeoffs at really high temperatures getting it there too, though the FADEC with Auto throttle on shouldn't allow that.

 

Of course some kind of failure (simulated FADEC failure, engine control module failure, engine surge, compressor stall etc) might overspeed the N1 too..


qfafin.jpg
Trent Hopkinson, 2015 Crewmember of www.mangrove.com.au WorldFlight sim

          Youtube channel www.youtube.com/user/musicalaviator

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Like hopskip says if you was in manual mode maybe you exceed the N1speed limit not likely to happen with auto throttle engage or a simulated failure this apply not only on the triple seven applies for the 737,747, MD11 also...or maybe the insane condition of the weather engine of fsinn.

 

Mitchel

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Had this happen to me the other  day,  thought it  would  trigger  an alert or  something but  seeing the red boxes  appear  is  enough of  an alert -_-


I7-800k,Corsair h1101 cooler ,Asus Strix Gaming Intel Z370 S11 motherboard, Corsair 32gb ramDD4,    2  ssd 500gb 970 drive, gtx 1080ti Card,  RM850 power supply

 

Peter kelberg

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Had it happen when I was taking off from Dubai as well. At some point during takeoff autothrottle disengaged and the N1 went sky high because I had the throttles pushed all the way forward. Maybee just back the off a tad on takeoff( I was using TOGA)

 

I'm sure this shouldn't happen in the real thing with AT engaged like it does in the sim because the throttle will suddenly jump to where ever you have it if AT drops for any reason. In my case all the way forward thus overspeeding the engines.

 

No way around it unless you have a $3k motorized throttle:/


Steve McNitt

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I'm sure this shouldn't happen in the real thing with AT engaged like it does in the sim because the throttle will suddenly jump to where ever you have it if AT drops for any reason.

 

 

Only way you could do it in real world would be to reach out with your hand and physically push the thrust levers all the way forward and hold it there with your hand.

 

Of course the throttle won't 'suddenly jump to where ever you have it', because it is where it is, being a physical set of objects.


qfafin.jpg
Trent Hopkinson, 2015 Crewmember of www.mangrove.com.au WorldFlight sim

          Youtube channel www.youtube.com/user/musicalaviator

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I landed the plane and then the red boxes disappeared. Still, I don't understand why they appeared anyway because the A/T never went off and I also didn't have my hardware throttle levers all the way forward. As far as I know, the engines didn't overspeed. The red boxes just appeared out of nowhere. Maybe it has to do with starting this flight from a saved situation, which I had not done before with the triple seven.


With kind regards,

Kevin Schepers

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Not in my case 


I7-800k,Corsair h1101 cooler ,Asus Strix Gaming Intel Z370 S11 motherboard, Corsair 32gb ramDD4,    2  ssd 500gb 970 drive, gtx 1080ti Card,  RM850 power supply

 

Peter kelberg

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This happened to me on takeoff. I used TOGA as usual but when the A/T went to HOLD mode the thrust went to where my throttle input was, maximum. At thrust reduction altitude the A/T went to climb thrust, controlling the thrust levers again. Leaving me with red boxes around the N1 and EGT indications.


ki9cAAb.jpg

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Do your hardware throttles continue to repeatedly command maximum thrust after you've stopped moving the throttles?

My Logitech X3D only sends information when the hardware throttles are moving but I'm not sure if that is the case for all throttles.h

See this thread for what I experience from my throttle behavior: http://forum.avsim.net/topic/422006-autothrottle-disarm/


Ho Cheung

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No way around it unless you have a $3k motorized throttle:/

 

If you are willing to sacrifice a touch of visual realism, you can actually. Just turn on the option to always show the physical throttle position, then while A/T is engaged match the physical throttle position indicator to the A/T commanded throttle position. Then if A/T is ever disengaged for any reason, you'll be commanding the same thrust setting.


Brandon Hathaway

UAL-1298

United Virtual Airlines

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My Logitech X3D only sends information when the hardware throttles are moving but I'm not sure if that is the case for all throttles.h

I believe, as far as FS is concerned, this is the norm... 

 

of course as soon as you get some noise... the FS would not know whether you are moving the throttle ever so slightly (or in some worse cases not at all slightly) or if it is just electronic noise.


--Peter Fabian 
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I believe, as far as FS is concerned, this is the norm... 

 

of course as soon as you get some noise... the FS would not know whether you are moving the throttle ever so slightly (or in some worse cases not at all slightly) or if it is just electronic noise.

 

I put a Null zone in my throttle via FSUICP, so "fully forward" and "Fully aft" are actually outside the movement range.

 

That said I'v heard some people who can't set a null zone like this and it instead puts a null zone in the mid-range, so pushing the throttle from idle to full, it passes an area around 50% where a large amount of movement results in no %N1 change. Which is bizzare and about as useful as a flyscreen on a submarine, ashtray on a motorbike etc.


qfafin.jpg
Trent Hopkinson, 2015 Crewmember of www.mangrove.com.au WorldFlight sim

          Youtube channel www.youtube.com/user/musicalaviator

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EEC should prevent you exceeding the red line. What's more likely is that you ran greater than max continuous thrust for more than 5 mins.

 

Where you in VNAV?


Jordan Forrest

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