Routine night launch,
so no awesome views of Earth
3 THOUGHTS ON “Stuff That’s Hard to Do (Falcon9 Starlink)”
Doug, 1:04 into the flight, was that the visual transition through the speed of sound? Or was that the throttling down for MaxQ? I have never seen or noticed that. No matter what, beautiful sight.
Henk ^
Glad you asked.
I almost pointed that out.
It’s a combination of the pressure wave generated by the vehicle’s shape and speed at a critical point of relative humidity. When the pressure drops suddenly, water vapor can briefly condense into that visible cloud ring. Usually see it with rockets around the time it’s trans-sonic
Yeah, this time it went through a few layers of different humidities, so it was doggone cool
Also:
Max-Q is the point of maximum dynamic pressure for that trajectory.
It’s a major design point for structures and control-systems engineers,
so it gets some attention in the narration.
Q = 1/2 (air density) (speed squared)
speed = 0 at liftoff, and
air density = 0 in space,
so there must be a maximum for Q somewhere during ascent
Next Week: the speed of sound as a function of density, temperature, altitude, and funding
(What? Well, I’ll need a week to read-up on that stuff. Been a looong time)
Doug, 1:04 into the flight, was that the visual transition through the speed of sound? Or was that the throttling down for MaxQ? I have never seen or noticed that. No matter what, beautiful sight.
Henk ^
Glad you asked.
I almost pointed that out.
It’s a combination of the pressure wave generated by the vehicle’s shape and speed at a critical point of relative humidity. When the pressure drops suddenly, water vapor can briefly condense into that visible cloud ring. Usually see it with rockets around the time it’s trans-sonic
Yeah, this time it went through a few layers of different humidities, so it was doggone cool
Also:
Max-Q is the point of maximum dynamic pressure for that trajectory.
It’s a major design point for structures and control-systems engineers,
so it gets some attention in the narration.
Q = 1/2 (air density) (speed squared)
speed = 0 at liftoff, and
air density = 0 in space,
so there must be a maximum for Q somewhere during ascent
Next Week: the speed of sound as a function of density, temperature, altitude, and funding
(What? Well, I’ll need a week to read-up on that stuff. Been a looong time)