Hello everyone, I have a question that itches me, how can we calculate the different speeds at the time of take-off? I can’t see on navigraph simbrief. Thank you
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This is a little outdated, but here you can find some rough numbers:
Other than that, you can purchase Infinite Flight Assistant which has the ability to give you those speeds depending on your weight, even if simbrief doesn’t show them in that particular flight plan.
There are surely other ways to find the V-Speeds out, but those are the two easy ways I know off the top of my head.
Thank you very much
You can also use IF assistant
It’s Free ?
In the “OFP layout” option on the right select JBU or JZA, the speeds will appear in the generated OFP where it says “take-off and landing data”, if I’m not mistaken.
Not all planes have v-speeds data in the Simbrief, for those that don’t you can find information on the internet.
Use IFPL Converter!!! It has V-Speeds.
I use a Program called Toper- Web
its only for 737 and 777 series and its subscribtion
You select the variant, lets say 737-800
then enter all the other data regarding the TO.
Airport ID Runway, wind, temp, weight , flaps take off thrust, QNH ( always 1013 in IF)
such as Max thrust, (TO) or derated TO-1 or TO-2
it then Calculates your V-Speeds.
The key is the Thrust setting N1 …that is what is also needed…Boeing uses three.
Max trust by engine type , and 2 derated thrust levels.
There are some V-speed charts online for Airbus Boeing CRJ and most AC if you search
I had charts for all types in IF at one time
For Boeing 737/777 example I use Max thrust takeoffs at 98% N1 or TO-2 93% N1 based on weight runway length, wind . The V1 / Vr /V2 you can find on V-Speed charts by weight/Flap config because temp isn’t a real factor in IF .
TO-1 is 93% N1 derate
TO-2 is 87% N1 derate
These are estimated from real Boeing numbers
but in IF we can’t use real world Temp and other factors. Ex: A takeoff at max thrust in real life at sea level and 19° C the N1 value maybe 88%N1
and at 4000’ MSL and 31°C Max thrust may be a N1 of 103% !
(I emphasis Thrust N1 because its relevant in working with V-Speeds.)
We cant duplicate these factors in the game
so find V-Speed charts for the plane online
by weight not temp.
Then test your plane in solo starting at MTOW
no wind at the recommended V Speeds for that weight and a thrust of 95 %N1 to 98% N1 and see if it performs as it should… then drop the weight to med load , use the new V speeds for that weight and TO at 95 thrust. etc .
Note that the lower AC weight accelerates faster at the same thrust of 95%N1 so thats when you can use derated thrust and lower TO thrust instead
Its all a balance.
Many operators to save on engine wear and tare
use reduced thrust settings unless weight , runway length and temp require a max thrust takeoff.
So when you see TO N1 settings like 84% to 88%
thats probably derated unless its freezing out
and the V-Speeds may be higher.
lastly thrust reduction is used around 1000 to 1500 feet or higher to cliimb thrust to throttle back the engine wear.
So how does this help you with V-Speeds
You have a few options in IF !
First use the training vids and V-Speeds /Thrust recommend by IFC users and Devs.
Second look up V-Speed data online by airframe type and variant and use that , but you will need to try different N1 trust settings to get it coordinated with them. Flap settings also are factor.
the V-Speed charts can give you those V-speeds
at different takeoff weights , and flap configs.
all you need to do is test them out in IG
and figure out what thrust settings to use
or like in the case of my 737/777/752/787 Boeings
I use three thrust settings and V-Speeds
based on weight , runway length and wind.
Unless an unusual climbout is required
I try to use TO-1 derated Thrust N1
93% N1 as much as I can. I get my V-Speeds based on the Toper-Web calculator.
But the free charts have similar speeds as it provides .
I use charts I made up for my Airbus’s and other AC
I probably confused you?
Don’t use my V-Speeds in this pic they are too high
its an old chart I made up. It just for and example.
(I had these for every AC in IF , but they got wet and damaged)
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Thank you very much everyone
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