It don' really understand why Vy is different that Vx?!

Question

i mean, Vx=you just make the max. pitch, so therefore you make the most altitude gain in the fewest way. Vy=velocity for best climb. but i imagine it like you just make full power, therefore also pitch max., and you have your best altitude gain in the least amount of time...?!

Answer 1

Vx is used to attain highest altitude possible in the shortest time and distance at climb power.

Vy is used to attain both the best rate of climb and best airspeed at climb power. At Vy your rate of climb is lower but of course your airspeed is higher hence distance covered is greater than at Vx.

O.K. my answer was as clear as mud! sorry:-(

Vx--  Highest altitude in shortest distance. ( Best angle of climb)

Vy-- Highest altitude in shortest time.( Best rate of climb )

Answer 2

"Max pitch"?  What is that?

Answer 3

Remember, we're talking about airspeed, not pitch angle.  You're going to adjust the aircraft pitch to obtain and maintain either Vx or Vy.  You will not pitch up as far as you can.  You will most likely have full throttle because you will probably want the best climb rate.  If you retarded the throttle, your climb rate would go down (but you would still adjust the pitch of the plane to maintain your target airspeed of Vx or Vy).  A common saying you hear in the small plane world is "pitch for airspeed, power for altitude".

Vx would be useful if, say, you needed to avoid hitting a mountain.  In this case, you're not really concerned with how high your climb rate is, just as long as you can get above the mountain without hitting it.  

Vy is useful if you just want to get altitude as quickly as possible, but you don't care about covering more ground distance to obtain it.

Answer 4

No, Vx gets you the higest in the least amount of ground track.  Vy gets you higest in the least amount of time.  Sure, in Vx, you sacrifice a little speed to climb in a shorter distance.  And sure, in both you may be at full or climb power settings, but it depends on what is important to you at the time: getting as high as you can in a short space (like clearing trees at the end of the runway) or getting high FAST (like meeting a crossing restriction)