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V- numbers

stamper

Well Known Member
okay where is everyone getting there Vne and such numbers for their rv10. I am ready to put all this together.
 
Here are some to start with:
Vne Never exceed 200 kts
Vno Normal operations, smooth air 188 kts
Va Do not make full or abrupt 125 kts
control movements above.
Full elevator would generate 6G
Vfe Flap extension speed (1/2 max): 95 kts
Vfe Flap extension speed (full max): 87 kts

Vy Best rate of climb speed 95 kts
Vx Best angle of climb speed 85 kts
Best glide speed 85 kts
Va Maneuvering air operating speed 125 kts
Vso Stall full flap 53 kts
Vs Stall, no flaps 62 kts
Vfe Maximum full flap speed 87 kts
Landing Final approach speed (full 40 deg flap) 70 kts
Demonstrated crosswind velocity 25 kts
Take off rotate speed 65 kts (less if using flaps)



2.02 Airspeed indicator Markings
Marking Indicated Airspeed
Red line (Never exceed) 200 kts
Black Line (Maneuvering speed max) 125 kts
Yellow (Caution - smooth air or light turbulence) 155/200 kts
Top Green Arc (max structural cruise) 155 kts
Bottom Green Arc (Flapless stall) 61 kts
Top White Arc (max speed full flap) 87 kts
Bottom White Arc (Stall, full flap) 52 kts
 
Structural numbers (Vne, Vno, etc) most people just copy from Vans. Vx, Vy, stall speeds, are to be determined during phase one testing for your airplane.

Carl: Vno is usually the top of the green arc. You list two different numbers??

And then there is the Vne controversy: While normally certified aircraft list Vne in KIAS, someone at Vans wrote an article saying Vans' Vne was meant to be KTAS.
 
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Structural numbers (Vne, Vno, etc) most people just copy from Vans. Vx, Vy, stall speeds, are to be determined during phase one testing for your airplane.

Carl: Vno is usually the top of the green arc. You list two different numbers??

And the there is the Vne controvery: While normally certified aircraft list Vne in KIAS, someone at Vans wrote an article saying Vans' Vne was meant to be KTAS.

Yep - Vno (188 kts) is above the green arc and in the yellow arc. I set Vno at 188 kts as this was my wings level speed at 2500 rpm.

I adhere to the 200 kts Vne as TAS. This is more conservative than IAS and there is little logic in exceeding it.

Carl
 
Yep - Vno (188 kts) is above the green arc and in the yellow arc. I set Vno at 188 kts as this was my wings level speed at 2500 rpm.
Carl

Vno is a number set by structural limitations, e.g., at speeds below Vno the wing won't fail in level flight at certain specified gust loadings. If you want to set it higher than Vans' numbers it should be based on engineering analysis, not how fast it will go. Unless, of course, you've flown it at 188 knots thru the specified turbulence, and noted no damage.
 
Carl

Where or how did you come up with best glide being 85 knots. I have always struggled getting a good reliable value for this.

Cheers:)
 
Carl

Where or how did you come up with best glide being 85 knots. I have always struggled getting a good reliable value for this.

Cheers:)

I did my best to record rate of descent at various speeds (engine at idle, prop forward). I plotted Vertical speed vs IAS, drew a smooth curve thru the data points, drew a straight line from the origin that just touched the curve, noted the airspeed at that point. That should be best glide at the test weight. Muliplied by the square root of gross weight over test weight to get published Vglide, which came to 86 kias. All that said, when I put my estimated error bars on the data, I could see that this method wasn't all that precise. I'm open to other ideas?
 
I should add that I'm not that concerned with having a precise value for best glide speed. In the real world, following an engine failure, the best speed to maximize the distance over the ground varies not just with weight but also wind, so you always end up doing some trial and error technique, using your eyes to judge as best you can.
 
And...

And sometimes you do not WANT the most distance covered. Sometimes duration is better than distance. Point is, I have seen many pilots choose to go long when a viable field was almost below them...You can't beat good SA, and knowing how your aircraft performs is definitely a part of that...
 
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