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jay907uk

VNAV Climb rate

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Hi,

 

Will the SP1 include a fix for VNAV climb when you depart as I find it climbs like a rocket. Or is it best to use V/S on departure.

 

Thanks for any advice offered.

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Hi,

 

Will the SP1 include a fix for VNAV climb when you depart as I find it climbs like a rocket. Or is it best to use V/S on departure.

 

Thanks for any advice offered.

 

Using V/S during the initial climb is bad idea, no speed protection.   Nothing wrong with VNAV so no need to fix it. Take a look at your technique and use all the tools at your disposal.  Derate your climbs if you fly with a light load. 

 

Modern twins do climb like rockets at full rated thrust with an average to light load, certification requires a certain minimum climb gradient on only one operating engine.

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Rob,

 

Thanks for the reply. Would it best using a Assumed Temp to actually de-rate the take off which will then make the VNAV climb out better?

 

I must admit I'm not the world's best person with the 777  :lol: .

 

Thanks once again for your help, I think I just need more practice with it to improve myself with it.

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Hi Jason,

 

An assumed temp is not the same as a derate.  To derate simply select TO1 or TO2 for take off phase, to derate the climb select CLB1 or CLB2.  I should add that you will burn slightly more fuel using a climb derate.

 

Good luck! :)

 

 

 

.

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220,000lbs of thrust will do that to you.  It's not an A320 for sure.  Enjoy the nice bird.

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It's not an A320 for sure

 

Have you checked the thrust to weight ratio of the A320? :) 

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Will the SP1 include a fix for VNAV climb when you depart as I find it climbs like a rocket.

 

No fix is necessary.

 

What you're seeing is the realistic approach to strapping two giant turbofans under the wings of a lightly-loaded airplane.  As mentioned, have the plane reign in the thrust by using a de-rate or assumed temp for takeoff/climb (this is also mentioned in the tutorial, which I highly recommend you fly - even if you think you know what you're doing).

 

Always ensure you're doing things properly yourself before trying to push the fault off on someone else  :wink:

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So an initial climb rate of 5000 fpm with a light 777 is OK?

yes. Use derate thrust  or temp ( using topcat or aurusim efb which is coming soon hope its not dead) 

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I know a light 777 can easily climb 6000 fpm, but will the passengers be puking I the aisles?

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I know a light 777 can easily climb 6000 fpm, but will the passengers be puking I the aisles?

Why would they? If you're in a constant climb no one will care (or can tell the difference) between 50fpm and 5000fpm*. Smooth delta V is the key, not the V itself. 

 

*Rapid pressurization is not really an issue either as the plane will mange its own cabin climb/descend rate somewhat independent of the plane's rate.

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Why would they? If you're in a constant climb no one will care (or can tell the difference) between 50fpm and 5000fpm*. Smooth delta V is the key, not the V itself. 

 

*Rapid pressurization is not really an issue either as the plane will mange its own cabin climb/descend rate somewhat independent of the plane's rate.

Correct. Here is another awesome one for ya just uploaded by Boeing:

 

https://www.youtube.com/watch?feature=player_detailpage&v=GZRKm6PG918

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I know a light 777 can easily climb 6000 fpm, but will the passengers be puking I the aisles?

 

Passengers don't feel vertical speed, they feel accelerations (aka G forces). As long as the climb is eased into, no one's going to know the difference between 2000 and 6000 or anything else.

 

As others have said, if you're light, derate your takeoffs. I often use the full TO-2 fixed derate with 99C assumed temperature in the 200LR if the plane's basically empty. If you get TOPCAT it'll calculate values for you based on the exact weight and runway length etc.

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