He is gaining speed, it is necessary that he does not do this
Sukhoi Su-27/30/33/35/37 Flanker series & Su-34 Fullback - History, Design, Performance & Dissection
You don’t understand what you’re writing about.
Depending on the design, they can act as an aerodynamic brake.
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There is no such thing as a grid fin airbrake. Makes zero sense.
My apologies, you are right about things here and there. Matter of fact very often. I respect what you post most of the time, even now. You always bring a unique perspective. I admire it. But like all of us we get it wrong once in a while.
You would not let me go on incorrect about something, right? Why would I let you? I appreciate correction it’s how you learn. You should too.
Soyuz did not need to slow down in emergency abort. They need to straighten & stabilize in a emergency. A higher drag grid fin accomplished that immediately.
Having draggy stabilizers toward the back of the package quickly straightens out its flight & provides the maximum separation from the booster during the powered portion of the escape and allowing the fairing to separate cleanly from the spacecraft after the escape tower burns out.
Stable flight of a rocket requires that the center of aerodynamic pressure be behind the center of mass. The Soyuz LES abort has to carry both the orbital module (uncrewed during launch) and the reentry module (crewed) with it because the orbital module is stacked above the reentry module. The service module below that is left behind during an LES abort.
Without the fins, most of the pressure would manifest at the point where the base of the LES tower meets the top of the spacecraft fairing, above the orbital module. The center of mass is near the top of the orbital module when the LES is ignited, moving backwards as the LES rocket propellant is expended. With the center of mass behind the center of pressure, the stack would be unstable. Adding the fins moves the center of aerodynamic pressure back, yielding a stable configuration.
I just showed you a diagram of the Soyuz in English and Russian. Did that say Stabilizer or Air Brake?
стабилизатор
РС-grid stabilizer
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Whats under that redline?
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numbers
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Quick question: Are you capable of understanding english sentences?
Because through the whole thread you always seem to completely misunderstand every source you look at and take things out of context whenever you feel like it.
The sentence you quoted is literally confirming what MiG-23 said, namely that SpaceX does NOT use any russian parts.
They had an opportunity BECAUSE they didn’t use them. Their competitors did so they had a problem, SpaceX did not. The only way they could have had this opportunity is with them not relying on any russian tech.
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“can act as” and “are designed for” are two completely different things.
i think you two are discussing different things and trying to read the others texts as if they are about your thing and not theirs thus believing they are wrong.
When in fact i think both if you are correct.
-Grid fins are DESIGNED for guidance and steering.
-They INDUCE DRAG and have the POSIBILITY to be used as airbrakes if needed (even though that isn’t the primary use) by angling them to counteract each others rotational momentum.
Grid fins are not used as airbrakes as their ONLY function in any application where they are present. That would be an extremely bad design choice as there are far more efficient airbrake designs out there.
Non-moving grid fins are used in the exact same way the back end of a dart is; To use the off-angle induced drag to create momentum to right-angle the object whilst moving.
if you design them to be airbrakes then they are no longer grid fins.
no one designs them as air brakes.The “air brake” and the lattice wing is a conditional concept. Since it is possible to make a wing with a large resistance, or it is possible with a small one.
At the same time, they are also used for stabilization and control
And now calculate the thickness of the aerodynamic brake, the fastenings, the power of the hydraulic cylinder that releases the brake and the weight.And you’ll realize that at such speeds, a grid with a lot of plans and a thick profile looks better
How in the world is that nonsense?
no need for the attitude man.
well… again, why the attitude?
i fail to see in any way what so ever how i wrote anything wrong here.
It isn’t. you can’t change the name of something depending on what it does in the moment. it’s designed and named for a primary purpose.
I can use a plastic bag as a parachute, but that doesn’t make it a parachute.
I can use a fork to cut something but that doesn’t make it a knife.
Just because they can be used as brakes doesn’t inherently make them brakes.
at hypersonic speeds yes, but that isn’t its primary purpose. The primary purpose is guidance, that is why they are named fins instead of brakes.
The breaking is primarily done by angular re-entry, making the density of air increase at a slower rate than a straight entry would, utilizing the body of the craft for friction and at times of peak acceleration (or deceleration need) using the engines.
I don’t think the discussion needed to progress this far, Ziggy already proved himself wrong and followed it up with “I was always right”… Twice… Lmao
Let us focus on the Su-27.
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Sometime ago I found a list of Su 27 accidents but I don’t know where , does anyone know where to find it ?
But you can make stabilizers with increased aerodynamic drag.
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They don’t understand that grid fins are more easily used in multiple roles than conventional fins. Let them be ignorant.
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Which is exactly what my first reply to you was about?
@MiG_23M
i have made no claims as to anything to the contrary.
You replied to BBCRF and then tagged me…?
because you commented on his reply to me. so i answered you as well.
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@BBCRF he clarified at what he was referring too. With a single post. There was nothing more to say.
Who the hell are you?? Why are you hurt?
Random user who is upset over a conversation that took place hours ago that had nothing to do with him or the topic.
Here, take an L too.
SpaceX’s first rocket to use Russian engines was the Falcon 9, which launched in June 2010. The company has since used Russian engines on the Falcon 9 v1.1, Falcon Heavy, and Dragon 2 spacecraft.
Yes, SpaceX uses russian RD-180 engines on its Falcon 9 rocket.
Does spacex use russian engines? - Exploration of space (spaceheavens.com)
Word of advice random user, mind your own business. You’ll live longer.