What is Va and Vne when talking about flying? Something to do with aircraft design is what i can gather?

Question

What is Va and Vne when talking about flying? Something to do with aircraft design is what i can gather?

Answer 1

Small correction on Va.  It is true that maneuvering speed increases with an increase in weight, and that it is partially due to a heavier aircraft being less subject to abrupt accelerations.  There is another reason though.  Aircraft are designed so that the center of gravity (where the weight is effectively centered) in slightly forward of the center of pressure (where lift is centered).  This creates a slight nose-down pitching moment, which is counteracted by tail-down force created by the horizontal stabilizer.  Because of this nose down moment, the wing has to fly at a positive angle of attack in order to maintain level flight.  The heavier the aircraft, the higher the angle of attack that must be flown to maintain steady, unaccelerated flight at a given airspeed.  Now, we know that maneuvering speed means that the aircraft will stall before it is overstressed.  An aircraft will always stall when reaching its critical angle of attack, which is a fixed value.  The heavier airplane is already flying at a higher angle of attack, which is closer to the critical angle of attack.  Therefore, it will stall sooner, and with a smaller increase in angle of attack than a lighter airplane will.  Because of this, you can fly a heavier airplane at a faster airspeed.

Answer 2

Va= Maneuvering Speed

Vne=Never Exceed

Answer 3

speeds

relation to aircraft design? yes, because the design determines how fast the plane can manoeouvre and how fast it can go before it suffers a catastrophic break up

Answer 4

Va is maneuver airspeed, and varies depending on the aircraft weight.  Vne is Never Exceed speed - self explanatory there.

Va - in a nutshell - is a speed in smooth air where you could safely make abrupt control inputs without damage to the airframe.

Hope this helps.

ATIS

Answer 5

Va  applies when full and abrupt elevator deflection causes positive G force--not negative G force.  A speed considerably slower than Va must be flown to fully and abruptly induce negative G force with the elevators and not risk damage.

Va doesn't apply to repeated full and abrupt elevator deflections.

Answer 6

a Small correction on Vne

Vne - Velocity Never Exceed Speed- is the maxium speed that the aircraft is designed to fly at.. Above this speed, the dynamic airpressure on the aircraft can be enough to cause structual damage, and above this speed, an aircraft can start to have aeroelastic vibrations  which can result in excess G forces, and any control movement, can exceed the maximum load factor on the aircraft's design.

Above this speed, the aircraft could structually fail, meaning control surfaces and wings can bend, twist, dent or even shear off either from excess load factors, or the dynamic pressure of the air flowing over the wings.

Aircraft are designed to be able to exceed load factor by a margin of 150 percent, but that doesnt mean that nothing will happen, just means that the aircraft can absorb the excess load factor without catasphroic failure..

Answer 7

Eugene's answer is close, but here's a bit better info about Va.  Va is know as  design maneuvering speed (stalling speed at the maximum legal G-force, and hence the maximum speed at which abrupt, full deflection, elevator control input will not cause the aircraft to exceed its G-force limit). The aircraft will stall prior to any structural damage occurring. Maneuvering speed is adjusted based on the weight of the aircraft. As the weight increases, Maneuvering speed increases. This is because the aircraft is less subject to rapid acceleration at the higher weight.

Answer 8

There's a whole bunch of other "V" speeds that are relevant in flying.  some are applicable only to multi-engine aircraft, but most pilots and designers are familiar with these:

V1 Take-off decision speed

V2 Take-off safety speed (minimum)

Va Design maneuvering speed

Vb Design speed for maximum gust

Vc Design Cruising speed

Vd Design Diving speed

Vdf/Mdf Demonstrated Flight diving speed

Vf Design Flap speed

Vfc/Mfc Maximum speed for stability Characteristics

Vfe Maximum Flap Extended speed

Vfo Maximum Flap Operating speed

Vh Maximum speed in level flight with maximum continuous power

Vle Maximum Landing gear Extended speed

Vlo Maximum Landing gear Operating speed

Vlof Liftoff speed

Vmc Minimum Control speed

Vmca Air Minimum Control speed

Vmcg Ground Minimum Control speed

Vmo/Mmo Mach, Maximum Operating limit speed

Vmu Minimum Unstick speed (liftoff)

Vne Never Exceed speed

Vno Maximum structural cruising speed

Vpw Pilot Window open speed

Vr Rotation speed

Vref Reference speed

Vs Stalling speed

Vs1 Stalling speed in a specified configuration

Vso Stalling speed in the landing configuration

Vsse Safe Single-Engine speed (render an engine inop)

Vtos Take-Off Safety speed

Vtoss Take-Off Safety speed category "A" rotorcraft

Vww Windshield Wiper operating speed

Vx Best angle of climb speed

Vxse Best angle of climb speed, Single Engine

Vy Best rate of climb speed

Vyse Best rate of climb speed, Single Engine