Turbulence penetration speeds
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Turbulence penetration speeds
Lately I had a discussion with a friend about what happens when you fly in turbulence.
He said that he always flies at the indicated turbulence penetration speed.
IMHO and what I do is to fly maximum at the turbulence penetration speed or slower if altitude allows for a resonable speed between minimum operational and turbulence speeds.
I wanted to know if some of you from flight testing or engineering can support or refute my reasoning.
I think that it a very simple speed/mass issue. The slower i can fly in turbulence the less load I will put on my airframe and consequently my passengers. Is this reasoning correct?
My reason being that it represents an "envelope" limited by maximum speeds and minimum speeds. Therefore my comoft zone is rather in the middle than at the edge.
He said that he always flies at the indicated turbulence penetration speed.
IMHO and what I do is to fly maximum at the turbulence penetration speed or slower if altitude allows for a resonable speed between minimum operational and turbulence speeds.
I wanted to know if some of you from flight testing or engineering can support or refute my reasoning.
I think that it a very simple speed/mass issue. The slower i can fly in turbulence the less load I will put on my airframe and consequently my passengers. Is this reasoning correct?
My reason being that it represents an "envelope" limited by maximum speeds and minimum speeds. Therefore my comoft zone is rather in the middle than at the edge.
There are two speeds here, both defined a bit loosely in part 25.
Vb, the speed for maximum gust intensity, is the speed (usually only defined for larger passenger carrying aircraft) above which an aircraft shouldn’t fly in severe turbulence. It is also usually the maximum permitted value for Vra, which is the recommended speed for flight in turbulence (often the two coincide). Both are semi-arbitrary, and picked following a handling assessment that confirms it is high enough to ensure that a gust-induced stall is highly unlikely during such conditions. It also needs to provide adequate margins at either end between low speed stall warning and any high speed handling effects (sometimes called the low and high speed buffet boundaries).
So Vra is the optimal speed to fly at, and Vb is the fastest - but if they are the same (a single turbulence speed in other words) there should be no ill effect in flying at that speed, although the ride may be more comfortable slower.
G
Vb, the speed for maximum gust intensity, is the speed (usually only defined for larger passenger carrying aircraft) above which an aircraft shouldn’t fly in severe turbulence. It is also usually the maximum permitted value for Vra, which is the recommended speed for flight in turbulence (often the two coincide). Both are semi-arbitrary, and picked following a handling assessment that confirms it is high enough to ensure that a gust-induced stall is highly unlikely during such conditions. It also needs to provide adequate margins at either end between low speed stall warning and any high speed handling effects (sometimes called the low and high speed buffet boundaries).
So Vra is the optimal speed to fly at, and Vb is the fastest - but if they are the same (a single turbulence speed in other words) there should be no ill effect in flying at that speed, although the ride may be more comfortable slower.
G
