8KCAB high GW airspeeds?

B

Blackhawk

New member
I just thought of something. The Va is changed for the increase in gross weight in high gross weight AFM supplement, but nothing about the other airspeeds- Vx, Vy, etc. No appreciable change?
 
Actually, if I remember correctly, VA decreases with a decrease in weight

Here's a link that 'splans it all.

Bill
 
I understand the process of Va decreasing with an increase in weight. I did not write anything about Va increasing, just that it changed. Approach speed, Vx and Vy should also change. Vx/Vy changes are probably not significant. Approach speed, however should be higher since your stall speed will also be greater with the increase in weight.
 
No, VA Decreases with a Decrease in weight. I believe the formula is VA = VSo x (square root of the limit load factor)

Let's say your airplane stalls at 55 mph at max gross and the limit load factor would be 3.8. So, 55 x the Square root of 3.8= 55x 1.949 =107 mph

Now reduce the weight so the stall speed is 50 mph, and the limit load factor is still 3.8. So, 50 x the square root of 3.8 = 50 x 1.949 = 97.45 mph

So VA Decreases with a Decrease in Weight!

Bill
 
I was right the first time, wrong the second time. Or what I meant, not what I wrote. My initial point, however, was in areas where your speed will increase with an increase in weight... such as approach speed. Since your stall speed must increase with the increase in gross weight, I'm assuming your approach speed, Vx and Vy will also increase.
 
Wouldn't Vx and Vy would remain the same? The actual rate of altitude gained in FPM would decrease with an increase in weight but the air speed in which you achieved Vx or VY would remain the same.

Bill
 
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