SpaceX uses RD-180 on Falcon 9
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Any day now Ziggy
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Wait is that what you’re arguing??
Jesus christ stop making me agree with Mig_23M. The Grid fins ABSOLUTLY act as airbrakes. Really, anything that generates lift (in this case the force needed to manipulate the booster) necessarily generates drag and it’s a proportional relationship. If it generates a force on the booster through aerodynamic effects it MUST also generate drag.
They absolutely don’t. The Merlin engine used on the Falcon 9 is entirely homegrown. What you’re thinking of is the Atlas 5. That one did use the RD-180 and that’s why it’s now retired, replaced by Vulcan using BE-4s
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lol sorry, about that Prophet. I would never intentionally.
As for the grid fins, they are not airbrakes. they are at best stabilizers with higher drag for immediate stability for in the Soyuz in the event of emergency as explained in detail.
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Regarding the Falcon 9 its Grid fins are specifically designed for control of pitch, roll & yaw of the Falcon 9. They are hypersonic grid fins.
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Aren’t the grid fins just used for manoeuvring?
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Seriously, try comic sans
Kh-38?Kab-250?
Do you guys know where i can regularly check changes in the game through datamines? I usually check it on Reddit but those take a bit of time for them to post.
You should try to understand what you are reading before you ever highlight it & try to use it in a written argument.
This dude then proceeds to own himself with the first “source” he manages to provide…Funniest part is that he took the time to snip a screenshot, highlight in two different colors more proof that Falcon 9 grid fins have nothing to do with airbrakes, post it & directly ping me…
It is the landing gears that are dual use & provides the massive increase in drag to slow the 603 ton vehicle in reentry. it & directly pinged me… Your boy, Elon himself said it. The grid fins are not mentioned because they are irrelevant to the equation.
Now he is worried about bolded text?! lmfao.
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Question, when you were sitting there deciding on which highlighter colors to use, how excited where you?
Keep it real, you took the entire day to find what you somehow thought was some sort of mic drop bombshell. You failed to understand the context of what Musk was saying & were hyper fixated on the obvious. Large body surfaces generate drag & can reduce terminal velocity. This does not apply the grid fin, nor does it apply for the Falcon 9. Thats why it was not mentioned in drag and reducing any speeds.
If they were, Musk would have mentioned it as well. He did not because even though he is a hyper capitalist billionaire leader of the bourgeois larping as Tony Stark, he is not uneducated enough to believe hypersonic grid fins (the primary control surfaces the Falcon 9) would be optimized as an airbrake.
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This is the most primitive demonstration of an adult’s reading comprehension & the lowest capability to critically think I have ever seen employed in a written argument.
I am actually a little embarrassed that I ever engaged rather than pity.
You cannot even use the internet effectively to reinforce your points without impeaching yourself & highlighting the worst evidence that diffuses your entire thought process.
Dude screeched 24 hours on a completely made-up assumption that the Hypersonic grid fins of the Falcon 9 are actually OPTIMIZED as airbrakes & refused to provide a single source almost the entire time.
When he finally does share his one “source”. A transcribed statement from Elon Musk…
He ignorantly post & even highlights (lol) Musk’s clarification that the landing gear provides sufficient massive drag & are dual use in reducing terminal velocity by 50% upon retry in atmosphere. This dual use in the landing gear reduces the amount of propellant therefore more is available & dedicated to successfully stopping & landing the vehicle,
The 6ft grid fins are not mentioned by Elon Musk nor by any legitimate scientific source of producing enough drag to reduce the immense velocity & inertia (Kinetic Energy) generated by the 229.6 foot tall, 603.96 Ton (1,207,920lb) Falcon 9 as it hits all speed regimes in reentry & while in atmosphere.
It’s not mentioned because it is absolutely the most absurd, uneducated brain-dead idea that it would.
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Oh, look everyone, the textbook tactics of a loser.
When a man feels it necessary to moan about bolded text another man types TWICE because no one cared the first time is not a healthy look. Its only because you have nothing else to say but feel you must.
I specifically enhance the text to draw attention to those who have a poor reading comprehensions its very effective :) Thats why it’s most apparent when I reply to you. If I could draw a picture & use colored text I would because you sure as hell need them in all forms of communications. Understanding context is clearly not your strong suit. As shown in your highlighted “research” above into the Falcon 9 grid fins…
Everyone else can read perfectly fine, retain information & possesses a deeper understanding than basic surface reading. I do not need to bold text with anyone else really. Just you.
They are not used outside
6 R-77-1/M outside + 4 R-77M inside
Don’t have F-15, can do for MiG-29 later
Yes! This! So stop highlighting stuff. Or use comic sans so we know you’re posting satire.
(Yes it’s been quite obvious in this discussion that you’re defiantly and arrogantly wrong).
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You will have to wait for Su-35 for dual racks. It can carry 12 max.
again, i think the main argument gets lost as neither side here can act as adults.
“can be used as” and “are designed for” are VERY different things.
The grid fins on Falcon 9 are not designed as airbrakes, they are designed as stabilizers and guidance surfaces. I can find NO reliable sources that these specific ones are designed to used as airbrakes.
Do they add to drag? Absolutely. Can they be used to brake the decent? Absolutely. Are they designed for that purpose? no, not what i can find anywhere.
i actually found (cant seem to find it again though…) some places state the opposite. They have designed them with the front facing side having “peaks” at the intersections making them have lower zero-lift wave drag. This means that they have the lowest drag when not turning and thus needs to angle themselves to create meaningful drag.
Had they been designed with “valleys” instead i would have leaned more towards agreeing with you. Then they would have had better lift to drag ratios but would have created more drag at an alfa of zero making them inherently air-brake.
I do not have data on the Falcon 9 grille specifically, but most likely they were designed with a bias towards achieving significant drag
This is for the landing ship of the Unoin
Yes, i know those curves. they do however tell us nothing on whether the Falcon 9 fins were designed to achieve more (or less) drag than other designs of grid fins.
The choice of a design with “peaks” however does tell us something. It tells us that they made choices in the design to have the fins crate LESS drag at zero-lift. if you wanted them to act as airbrakes why would you design them to have less drag?
The fins having more or less drag at specific speeds is just the same thing as anything else would. that doesn’t mean that they were designed with the extra drag as an intent.
again “can be used as” is not the same as “are designed for”.
They are quite literally visibly tailored for that specific purpose. The basic design of the fin is best suited as both a surface to maximize drag (minimize terminal velocity) and also to help aid the precision landing at lower atmosphere when the RCS boosters are ineffective. The TVC isn’t useful when the motors aren’t firing as well.
These were required to reduce wave drag preventing control at all in the regions between subsonic and supersonic. They weren’t necessary on the thinner aluminum fins. They increased thickness and moved to titanium, at the same time they stopped using the landing gear as drag devices.
None of that is coincidence. If the grid fins weren’t necessary to slow the descent, they would have never made them larger, draggier, and out of titanium to handle the higher heat from the increased drag.
The fins themselves need a high level of precision over a wide range of speeds. That’s why they have peaks, it would be bad to lose all control to wave drag in transonic regions as this is a critical point in the boosters flight path.
Any grid fin not designed to slow something down would have ultra thin tips on the grids and the opposite is seen here.
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and i’m saying the opposite.
well yes, the basic design of ANY grid fin. not necessarily those specific ones. Edit: you know what, i re-read that and no, that isn’t a basic design characteristic. otherwise it wouldn’t be used on missiles.
Do you have a source for that? i have found nothing saying anything close to that.
Oh they absolutely did. The original aluminium fins burned up at reentry and couldn’t be re used. so they did titanium for RE-usability and then size/peaks for control authority, not increased drag. as specifically stated by musk: one , two and three.
Edit: i even found one where he explicitly states that the increase in size does allow for a longer glide but that it is a “minor factor”
this doesn’t make sense. Its a zero-lift drag reduction. meaning they reduce drag when NOT angled and when angled they have higher drag compared to that of valley types which does the opposite; more drag at no angle (working as air-brakes) but better drag to lift ratio when turning. so the opposite as to what you claim here.
this depends on speed, you cant have to thin leading edges at too high speeds. The forces would bend the metal and/or the heat-soak would be too little making them heat up MUCH faster and thus risk burning and braking due to the friction induced heat.
The specific fins on Falcon 9 were designed with RE-usability and control authority in mind, NOT air-braking. They absolutely do decelerate the decent, perhaps even more than i think, but that doesn’t matter to the discussion as my claim is that they were not DESIGNED with that as their purpose.
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