Parabolic Drag

[RockyMtnMT]

I tried to get an answer in another thread to no avail.

Can anyone tell me what parabolic drag is? Evidently it is caused by drive bands? I have never heard of it.

 

[Mark37082]

I googled it and the formula is way above my brain's ability to comprehend.

 

[RockyMtnMT]

https://agodemar.github.io/FlightMechanics4Pilots/FlightMechanics4Pilots/mypages/drag-polar/#:~:text=Aircraft%20parabolic%20drag%20polar

Over my head as well! It appears to be a drag that is associated with lift created by aircraft wings.

 

[Weaver93]

Aircraft Drag Polar

Aircraft Drag Polar Slides in Italian here. Aircraft parabolic drag polar $C_{D0}$, parasite drag coefficient at zero lift. , drag coefficient due to lift (induced drag). $e$, Oswald efficiency factor, includes all effects from airplane. , effective aspect ratio. $b_\mathrm{e}=b\sqrt{e}$...

agodemar.github.io

They have the slides in Italian which made as much sense to me as English.......perhaps a bit more.

 

[Mark37082]

Well if you don't put wings on your bullets, I believe everything will be just fine.

 

[Weaver93]

https://agodemar.github.io/FlightMechanics4Pilots/FlightMechanics4Pilots/mypages/drag-polar/#:~:text=Aircraft%20parabolic%20drag%20polar

Over my head as well! It appears to be a drag that is associated with lift created by aircraft wings.

I have to fly Monday so I'll ask the pilot with the margarita salt in his mustache how it works……he will know!

 

[trubkir17]

I read that term as well and I have been down an aerodynamic related rabbit hole for over 90 minutes. I have never read the exact term "parabolic drag". I have read about a "drag polar". This is a parabolic curve plotted out that determines drag for a given set of variables, if I understand correctly. I think that the poster who introduced this term has amalgamated a couple of different flight variables and then gave it a term that he understands but can't explain fully.

 

[dfanonymous]

I tried to get an answer in another thread to no avail.

Can anyone tell me what parabolic drag is? Evidently it is caused by drive bands? I have never heard of it.

There is no parabolic drag. There's your oddly worded to some, patent PDR…which makes sense to me. Not to be confused with rotating bands like on a 155.

Then, there's parabolic drag polar as mentioned above which is a aircraft physics term, as it relates to models/in a vacuum expressed in mathematics and focused on lift (to over simplify it, for the purposes of this forum.)

They have nothing to do with each other.

 

[cornshank]

There is no parabolic drag. There's your oddly worded to some, patent PDR…which makes sense to me. Not to be confused with rotating bands like on a 155.

Then, there's parabolic drag polar as mentioned above which is a aircraft physics term, as it relates to models/in a vacuum expressed in mathematics and focused on lift (to over simplify it, for the purposes of this forum.)

They have nothing to do with each other.

Also there is chocaholic drag , when , of course you can't find any chocolate.

 

[adam32+P]

Steve, don't take this wrong, but, if you don't know what parabolic drag is then how did you get a patent to "reduce" it?

 

[Muddyboots]

Actually it sounds more like a new woke gender.

 

[dfanonymous]

Steve, don't take this wrong, but, if you don't know what parabolic drag is then how did you get a patent to "reduce" it?

Not to talk for him but, It's not physics term "parabolic drag. "

It's parabolic (as in on the bands of the projectile/bearing surface) are parabolic and in doing so, (it alleges reduced drag.)

It sounds cool for marketing but it's horribly worded, I have to admit.

 

[JakeC]

Steve, don't take this wrong, but, if you don't know what parabolic drag is then how did you get a patent to "reduce" it?

by using the shape of a parabola to reduce regular drag.

It's like saying polarized sunglasses. It's not filtering polarized sun light, it's using polarizing to reduce light hitting your eyeballs.

 

[Mikecr]

I may be wrong, but I'll just think out loud about it here.
A shock wave is formed in front of our bullets, which is in the shape of a parabola. It is by itself traveling at the speed of sound (Mach 1).
The bullet picks up the shock wave while passing Mach 1. This is a big drag load, and I think of it like running with an open umbrella.
With each higher bullet speed over Mach 1 the umbrella closes a bit, reducing it's relative load. While the bullet slows to transonic, the umbrella opens more & more, becoming a bigger and bigger load.
That's how I functionally see it.

For each incongruity presented by the bullet's surface, where laminar flow is harshly disrupted, another parabola is formed.
That would be drive or crimp bands, and sometimes nose or base transitions. This only existing at supersonic velocities.
By subsonic the umbrella is fully released, letting go of that load.