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Take-off speed for the TBM 930?


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I thought the rotation speed (Vr) was 90 mph for the TBM but when I check Flight Assistant in-game in the Game Bar it says 53-73 mph at maximum load.

 

Which is it? Thank you.

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According to the manual I found on the web, with TO flaps it's 90 kts, though that might change slightly if you're light:

 

http://www.tbm.aero/wp-content/uploads/2016/04/PIM_900__AN__E1R0V3.pdf

 

Yes, thank you. But why does it say 'POH 53-73 mph' in Flight Assistance.

 

Take-off speed.jpg

Edited by oneleg
Win 10 Pro, MSFS Premium Deluxe Steam, i7-8700, 32 GB RAM, GTX 1070ti, hardwired 950 Mbps, wifi 5 Ghz 50+ Mbps, Gsync 27-in 2560 x 1440 Dell monitor, Logitech 3D Pro joystick, and Quest 2 VR
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That handbook is for a real aircraft. I don't have this particular sim, but it's possible that whoever made that aircraft has a lousy set of flight dynamics. But it's also possible that there's a bug in the program. But note that in your screenshot that's (53-73) Kts, not mph. BTW that says TAKEOFF SPEED, not Vr -- details do matter, though you DID say TAKEOFF in your title. TAKEOFF SPEED (presumably liftoff speed) will be greater than Vr, since the aircraft continues to accelerate after you start rotation.

 

And I have NO idea what the source is of the info on your screen above, so maybe it's a misprint/typo/etc. But perhaps there's something else going on there, too, since the LANDING SPEED is POH[108-84] Kts and stall is 83-65, and I can't image a landing speed of 24 Kts, or a stall speed of 18 Kts. And there certainly isn't a takeoff speed of -20 Kts.

 

So looks to me, unless sim instructions somewhere else say different, that there's a bug of some sort.

 

Larry N.

As Skylab would say:

Remember: Aviation is NOT an exact Science!

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I thought the rotation speed (Vr) was 90 mph for the TBM

 

The Garmin G3000 Pilots Guide explains Vspeed references for the TBM 930, see page 68 and 69. The airspeeds noted from the Guide seem to track pretty much the way I fly the default FS2020 TBM 930. HTH

https://static.garmin.com/pumac/190-02046-02_a.pdf

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....But note that in your screenshot that's (53-73) Kts, not mph. BTW that says TAKEOFF SPEED, not Vr -- details do matter, though you DID say TAKEOFF in your title.

 

....

 

And I have NO idea what the source is of the info on your screen above, so maybe it's a misprint/typo/etc. But perhaps there's something else going on there, too, since the LANDING SPEED is POH[108-84] Kts and stall is 83-65, and I can't image a landing speed of 24 Kts, or a stall speed of 18 Kts. And there certainly isn't a takeoff speed of -20 Kts.

 

So looks to me, unless sim instructions somewhere else say different, that there's a bug of some sort.

 

The screenshot is an MSFS screen capture while the TBM is on the runway ready to go.

Win 10 Pro, MSFS Premium Deluxe Steam, i7-8700, 32 GB RAM, GTX 1070ti, hardwired 950 Mbps, wifi 5 Ghz 50+ Mbps, Gsync 27-in 2560 x 1440 Dell monitor, Logitech 3D Pro joystick, and Quest 2 VR
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Those speeds are taken from the Reference Speeds section in the flight_model.cfg, which seem to have been copied and pasted from the C172 into all the other aircraft. You can safely ignore them for now.

 

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Sorry that I wasn't clear, but Tim supplied what I was wondering about, the source for the DATA that was displayed, not the source of the screenshot. The numbers make much more sense now -- a bug.

 

Larry N.

As Skylab would say:

Remember: Aviation is NOT an exact Science!

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I'm trying to pin down the facts with regards to speeds for the TBM 930.

 

Everyone(?) is saying that the Vr speed is 90 KIAS. But just what exactly, are the assumptions behind that assertion? Does that assume that the aircraft is fully loaded to the max?

 

I always take-off with default weights in the sim. I assume that's just the pilot and the co-pilot right? Each pilot weigh 170 lbs for a total load of 340 lbs (170 x 2). I don't mess around with additional passengers or cargo.

 

The empty weight of the TBM is 4582 lbs. Add the 340 lbs of both the pilot and co-pilot and it is now roughly 5000 lbs. Add the default weight of 50% fuel in each tank (about 1000 lbs total for both), and the Vr speed is a lot less than 90 KIAS according to the graph below. Am I reading the graph below correctly? Thank you.

 

TBM Normal take-off speeds-10-19-2021 9-36-50 AM.jpg

Edited by oneleg
Win 10 Pro, MSFS Premium Deluxe Steam, i7-8700, 32 GB RAM, GTX 1070ti, hardwired 950 Mbps, wifi 5 Ghz 50+ Mbps, Gsync 27-in 2560 x 1440 Dell monitor, Logitech 3D Pro joystick, and Quest 2 VR
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...

Guide seem to track pretty much the way I fly the default FS2020 TBM 930. HTH

https://static.garmin.com/pumac/190-02046-02_a.pdf

 

Thank you for the link. I hadn't seen it before. It is very helpful.

Win 10 Pro, MSFS Premium Deluxe Steam, i7-8700, 32 GB RAM, GTX 1070ti, hardwired 950 Mbps, wifi 5 Ghz 50+ Mbps, Gsync 27-in 2560 x 1440 Dell monitor, Logitech 3D Pro joystick, and Quest 2 VR
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In theory, for any airplane at a given configuration (flap setting and power setting) the ratio of two stall speeds for two different weights is V2 = V1 times the square root of W2/W1. If takeoff speeds are based on 1.2 times stall speed (or any constant for that matter), these ratios also work for takeoff speed
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