What is the Va speed?

Question

What is the Va speed?

Answer 1

@ cherokee, not really true that you would enter turbulent speed at Va, this would be maximum turbulent air entry speed=), which is normally lower than Va.

Answer 2

maneuvering speed, the speed you could put full and abrupt

deflection,of the control surfaces  that will cause  the plane to stall before you do structural damage.

this is the speed you would also slow down to when you experience turbulence

edit:

I guess I learned it wrong and  am  teaching it wrong,

silly me, I was basing my answer on the FAA's Handbook of Aeronautical Knowledge. Chapter 2...

cut and pasted directly from it..

• Design maneuvering speed (VA)—This is the

“rough air” speed and the maximum speed for abrupt

maneuvers. If during flight, rough air or severe

turbulence is encountered, reduce the airspeed to

maneuvering speed or less to minimize stress on the

airplane structure. It is important to consider weight

when referencing this speed. For example, VA may

be 100 knots when an airplane is heavily loaded, but

only 90 knots when the load is light..

Answer 3

Regarding above responses:

There are no color bands on the airspeed indicator on a jet. On a PFD, there might be colors if below 10,000  feet for the 250k speed limit, or if an airspeed has been targeted/selected by the pilot and there is a deviation.

Max turbulent air penetration speed is published for the jets I fly and is not the same as Va.

Va varies greatly by weight in jets.

The "maximum control deflection" referenced in the textbook definition of Va applies to full deflection movements to or from neutral and not to movements from full deflection in one direction to full deflection in the opposite direction.

Answer 4

Va - designed manerving speed- is the speed that the aircraft will stall before reaching the designed load factor limit.  I.E - the aircraft will stall before you can do any damage to any structure on the aircraft, and since any stall is only 1G, no harm can be done to the aircraft.  This can cleary be seen when looking at a VG diagram. The Va is dependentant on weight because as an object has more mass, the more inertia, there fore more force is required to deflect it from it path, this is why you will have a higher Va for a higher weight.  The yellow or caution range, is an airspeed at which any abrubt deflections can exceed the load limit design of the aircraft, and this why you only fly in the caution range in smooth air.

Answer 5

In plain english, Va is the speed threshold where the angle of attack required to maintain straight and level flight is close enough that a stall will occur (which is just reaching the critical angle of attack) BEFORE structural damage is received.

In other words, below Va, it is impossible to overload the wings because a stall will protect you from it.  Above Va, structural damage will occur before the stall.

Va increases with weight because as an airplane gtes heavier, it must operate at a higher angle of attack, putting it closer to the critical angle of attack, and therefore closer to the stall.

In this example, think of the stall as a good thing.  It protects your airplane from overstressing the wings if you were to apply full and abrupt control movements.