# How to calculate v speed in Infinite Flight?

Hello everyone. I hope you all are having an amazing day. So, I don’t know how to calculate V Speeds (V1, VR, V2) at Infinite Flight. Does anybody know how to calculate it?

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https://fpltoif.com/ This website calculates the V speeds for a couple aircraft.

If you install IF assistant (it costs \$5) it acts like a co pilot and as one of its features it can calculate V speeds based on aircraft, weight and flap setting

It calculates V-Speeds? I thought you can just insert V-Speeds not calculate them.

you can click on autofill then it calculates it

This app does not calculate the speeds, it only allows you to input a speed that the computer will then call out upon reaching it on takeoff

It calculates it for me atleast, i never type the speeds myself

It can do both, you can insert custom ones from your flight plan from simbrief for example, but also make it find its own ones when you click on “autofill” in the top left corner of the application.

Simple calculation:
1st calculate ToD (ToP of Descent):
In this order (ie. ignore math rules of order): current AGL minus AGL of destination and then divide by 1000.
Then:
Multiply the result by 3 (add 10 NM for other factors like wind etc).
The result is the distance from the destination to start descending.

2nd Calculate RoD (Rate of Descent):
The GS (Ground Speed) your aircraft is flying at x 0.5.
The result is (RoD) Rate of Descent.

Hope that helps!

I don’t think these are the correct calculations 🤣

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Yes, but i’ve noticed that it’s not always accurate, i’ll be flying in a 737 with light weight and it tells me to rotate at like 140 knts

He asked for the V-Speeds not ToD ;)

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Lol trying to teach a ground lesson here

Take a look at this topic (1) and this one too (2). The first has information for all aircraft, however, some are no longer valid because there are aircraft that have had rework, the topic identifies them with “(Old)”, these aircraft usually have a topic of “unofficial profiles” of them, do a search for them here. The second topic is a compilation of information from some official video tutorials that the IF team produced, you can find them on the official Youtube channel.

Also, as I usually say when I see a question like this, try to study the planes you fly, try to spend time flying more with a specific one or with more of one than others, it’s very good to do this in-depth, especially regarding these V-speed/performance questions.
I recommend that you use simbrief.com to plan your flights, it usually gives the V-speeds for some aircraft, and seeing your plan details in the OFP greatly increases the level of your simulation, and you can also have your route easily transferred from there for the IF using this tool (3) (topic about it (4))

Safe flights!

4. #### IF Flightplan Tools by Adam Callow

Rate of descent is V Speed

Rate of descent is “vertical speed”

“V speed” refers to the Velocities (“V”) to safely accomplish various stages of flight.

For example, pilots call “Rotate” at VR (Velocity Rotate) during the takeoff roll

based on the OP, being takeoff and climb … as a 737 player … unless hot and high with a short runway and 99.9% of the time everyday is unrestricted climb day … I do 87-92% N1 and rotates at 150 kts … then adjust VS to keep under 250 KTS till 10K … then unload my AoA to hit 320 KTS then let it slowly fall to 280 and adjust my VS to keep 280 until I reach cruise. Sometimes I’ll level off to regain speed if I get to close to 250 TAS or M .72 so I can at least back to .77 … If I time it right, I’m at .78 by cruise altitude

If I’m Southwest or even Frontier in an Airbus I’ll tend to go higher N1 to get to those higher Cruise Altitudes. If I’m a legacy carrier who’s cruise is much lower I’ll start around 85 N1 and unload the aircraft sooner to maintain airspeed.

Of course this depend on your weight and and airfield altitude. but to use an old pilot reference when in doubt, balls to the wall to get into the sky … TOGAs to get you off … you can always throttle back

Hello! If you want to know every aircraft v speeds, please check out this topic:

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it seems pretty accurate to me atleast

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You can also check out this site. There is a free app for the 777 & 737 on play store https://toper-web.com/