Some make a very big deal out of it. There are interminable threads on the subject on the Internet, with no real answers. Rogers, at my request, has kindly plotted the TIMES to reach 1, feet above a sea level airport, on a standard day, using Vx blue , Vy red , and a composite purple of Vx and Vy, where he uses Vx to about or feet, and then transitions to Vy.
Furthermore, he plotted the gliding time and distance assuming engine failure upon reaching 1, feet, and using best glide. These are the descending lines. This shows a total of only 7 seconds difference between Vx and Vy, arriving at 1, feet!
The difference between the two is approximately feet. This demonstrates to me, at least that the usual heated argument is not worth the breath it takes. Factors Climbing at Vx and Vy. If you are at Vx at very low altitude, you will be highly vulnerable in the event of an engine failure. The lower left corner of the above chart is shown below:. That area in red approximates an area where an engine failure will put you in a pile of flaming wreckage in most Bonanza-type aircraft.
Further, the average reaction time to an engine failure is four seconds. With the nose positioned for a Vy or worse, Vx climb, the pilot is afforded little or no margin above stall after accounting for this time.
The nose is much higher, blocking forward view for the entire time at low speed. On the other hand, you may hit them at a slower airspeed.
That nose-high attitude also blocks your view of potential landing sites. If your engine fails your hands will be full of airplane for a time until you get the airplane and yourself under control. Only then will you be able to take a breath, and look for a soft spot, your first opportunity to do so. Flying Tip. Gumersindo Echanobe Professional. How is Vy calculated? Projectile motion equations. Viktors Kollerer Professional. Does true airspeed increase with altitude?
Melodi Agasalho Explainer. What is VX and VY in physics? At the beginning the ball is thrown with an angle to the horizontal. V is its velocity and its direction is northeast.
Vx and Vy are the X and Y components of our velocity. Finally, when the ball hits the ground Vy reaches its beginning magnitude but opposite in direction. Chelsea Koseler Explainer. How does thrust change with altitude? Thrust is produced by accelerating air. Since higher air-speeds are normally used at higher altitudes , thrust generally decreases with an aircraft's altitude. But increasing altitudes can erode thrust because the mass of air being consumed is also decreasing as the air gets increasingly more rarified.
Oro Yakobson Pundit. Why does power required increase with altitude? At higher altitudes , because of the less dense air, you need to fly at a higher angle of attack for a given true airspeed. And, if you're flying at a higher angle of attack, you're generating more induced drag.
So, as you climb, your angle of attack for level flight increases and you generate more induced drag. Raico Bolinaga Pundit. Why does true airspeed decrease with altitude?
At the absolute ceiling, your Vx and Vy are the same speed. And by the way, if you try reach your absolute ceiling, it will take you quite a while to get there. Become a better pilot. Subscribe to get the latest videos, articles, and quizzes that make you a smarter, safer pilot. Aleks is a Boldmethod co-founder and technical director.
He's worked in safety and operations in the airline industry, and was a flight instructor and course manager for the University of North Dakota. You can reach him at aleks boldmethod. To: Separate email addresses with commas. Now What? All Videos.
Planes Careers. Aleks Udris Aleks is a Boldmethod co-founder and technical director. Recommended Stories. How DME Works. Fewer thunderstorms and less turbulence mean more days in the air for you. How is Vy calculated? Does true airspeed increase with altitude? How does thrust change with altitude? Thrust is produced by accelerating air. Since higher air-speeds are normally used at higher altitudes, thrust generally decreases with an aircraft's altitude.
But increasing altitudes can erode thrust because the mass of air being consumed is also decreasing as the air gets increasingly more rarified. Why does power required increase with altitude? At higher altitudes, because of the less dense air, you need to fly at a higher angle of attack for a given true airspeed. And, if you're flying at a higher angle of attack, you're generating more induced drag. So, as you climb, your angle of attack for level flight increases and you generate more induced drag.
Why does true airspeed decrease with altitude? Thus, at higher altitudes, lower air density airspeed has to be higher in order to generate the same dynamic pressure at the Pitot tube, and the opposite is true for lower altitudes higher density where airspeed has to be lower in order to generate the same dynamic pressure.
How does drag vary with altitude? Lift and drag depend linearly on the density of the fluid.
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