Rocket engine cycles: How do you power a rocket engine?

Rocket engines are incredibly complex machines, pushing the boundaries of material science and human ingenuity. And there’s a wide range of ways you can actually power a rocket engine and make it work.
They can be super simple, like just opening the valves of a tank under high pressure to having complex pumps arranged in a fashion so confusing it’s a miracle anyone ever figured out how to build them in the first place.
So today we’re going to talk about cold gas, pressure fed, electric pump fed, open cycle, closed cycle, full flow staged combustion, tap off and expander cycles. We’ll go over their pros and cons and lots of fun examples of each one!
Check out our article version of this video too for sources and links! - everydayastronaut.com/rocket-...
00:00 - Intro
02:55 - Basics Of Rocket Engines
05:35 - Cold Gas Thrusters
10:25 - Monopropellant Pressure Fed
14:15 - Bipropellant Pressure Fed
17:45 - Electric Pump Fed
21:05 - Open Cycle
25:40 - Closed Cycle [Ox Rich]
31:15 - Closed Cycle [Fuel Rich]
35:25 - Full Flow Staged Combustion
44:25 - Tap-Off Cycle
46:45 - Expander Cycle
52:20 - Summary
--------------------------
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[@ardag1439]

I think we forgot about the cycle where you rupture the propellant tanks and use the whole vehicle and its surroundings as the combustion chamber.

[@ryanthompson7884]

clearly the best

[@saadusmani78]

From what I heard, this type of cycle is called RUD (Rapid Unscheduled Disassembly) Starship SN10 used this to make a reflight in under 10 minutes after landing! Now that's an impressive turnaround time.

[@ArodWinterbornSteed]

I don't think you understand the concept of a 'chamber'

[@ShuttleEnjoyer]

The full flow “KSP” cycle

[@letsgocamping88]

what about the one where you throw bits of engine out the back?

[@jamesengland7461]

A "like" is a given; a comment is grossly inadequate to convey my gratitude for the stellar work you do!

[@roelende9670]

same

[@sockpuppety]

honestly your content is beginning to feel more and more like curriculum as it gets fleshed out and cross referenced. very few people would have the stones to go into as much detail as you have done. thank you for caring about getting it right. you are a researcher and presenter of quality sir.

[@itzzitzz]

I thinks he's teaching actual rocket engineers

[@ASJC27]

@@itzzitzz No

[@SoumilSahu]

@@itzzitzz Nope, it's amazing content, but it's mostly surface level. It's just right to get you excited to delve deeper if you want, but its not gonna help you make a rocket engine. Like he claims, the purpose of Tim's channel is to bring space down to earth for everyday people..

[@PracticalEngineeringChannel]

Masterclass in breaking down a complicated topic. Great job to you and your team!

[@logank444]

Hey my favorite engineer commenting on my favorite rocket scientist. How sexy

[@samkachar]

So great seeing you here. Love your content as well. Not surprised to see current and future engineers here.

[@jeffreyhill1011]

Number 1 dirt content creator on the interwebs!

[@fish2468]

@@logank444 my thought too pure hundred percent *S3XY*

[@oldjimlxi5586]

@@samkachar ❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤

[@f205v]

Tim, the nerdier you get on mathematics and physics, the more enjoyable your videos are!

[@TechNextLetsGo]

I learned more about rocket science in the last 30 minutes than I have in 5 years, wow dude. You are good at teaching this.

[@koomaj]

I'm still amazed this level of content is totally free for everyone to watch. Thank you Professor Tim!

[@Lpabmendez]

Free? I had to sit through several advertisements

[@koomaj]

@@Lpabmendez Wathcing advertisements is also free, unless you was convinced to buy something =)

[@screenname1]

I suspect that it's funded.

[@spacecowboy5274]

i have a question 8:50 over here how will the gas turn into a liquid??

[@MasterMe1984]

@@spacecowboy5274 I think if the gas is losing pressure it's loosing heat, so it turns back to a liquid.

[@KevinTheCaravanner]

We use “rocket science” as a term to indicate something is extremely complex. And it is, but you present it so well that I understand it. You’re a legend Tim.

[@Muuip]

Exactly! I totally agree!👍 Thanks to Professor Tim and team.👍

[@warrengans1346]

This is only one part of it: staging, orbital mechanics...

[@KALLEFUCKINGANKA]

Rocket science is really simple, throw hot stuff out really fast in one direction and go the other. Rocket ENGINEERING however, now thats complex!

[@Titter2]

I understand just enough to know why I don't understand it...and that's all I can ask for.

[@VeggiePower303]

Rocket science is NOT complicated. As you can see it's all very simple. If you look into the operations of a Modern Super-Turboed Diesel engine in depth. You will see it has more moving parts hence it is more complicated.

[@DonDegow]

This video helped me a lot, gradually increasing the complexity is what made me understand, thank you!

[@snuffeldjuret]

indeed very well put together!

[@robertgraham6481]

This is a masterpiece. Structure, flow, pacing, diagrams, animations, clips all spot on. Thank you very much.

[@screenname1]

You react with such enthusiasm because you think it's a solo effort.

[@flybeep1661]

Lol, "masterpiece", dude get a handle on yourself. Exagerated BS, it's a nice vid, nothing more.

[@acanuck1679]

This, Tim Dodd, was a tour-du-force. Your attention to detail and the effort you put into ensuring that we (your loyal audience) actually understand what you are trying to explain to us was obvious. This video was a really good primer about rocket engines and the diverse choices that engineers and designers can make when trying to "build a better mouse trap". Thank you.

[@jasoncy31]

I'm overwhelmed at how good this was, Tim. At first I thought "well, this is obviously a setup for a paid curriculum/class". Can't believe that you offer this for free to the world. You're doing an important service to space and science education and should be proud of what you've accomplished. Well done, sir.

[@The_Dark_Lord-69]

I like how you took us from a simple party balloon to Raptor 2 engine. Thank you very much. No lecture would be able to understand those basic concepts as fast as you did.

[@FureyinHD]

I'm an aircraft engineer and I've learnt so much from you about rockets. You're like an old fashioned engineering teacher who's not afraid to challenge students with depth information. Thanks, Tim!

[@yagwaw]

Absolutely magnificent! I thought I already had a pretty good idea of cycle types, but still learned a lot. Each time a question arose in my head, you did immediately address it in the next sentence or so.

[@websitemartian]

could you explain the difference between the rocket engines used on planes/jets versus these? and why wouldn't raptor be used for jets ?

[@TheDerpsKast]

I've been following you for years Tim. Since before Boca Chica, and even since before Starhopper took it's first hop. I'm consistently amazed by not only the understanding you've garnered regarding these incredibly complex topics, but the simplicity with which you explain them. I've always loved space and spaceflight, but you were the catalyst for much of my understanding of its nuance. For that, I cannot thank you enough.

[@martinstedtler]

Can you make a video about the structural engineering of rockets? I am always amazed how they transmit hundreds or even thousands of tons of thrust into the chassis, without everything just getting crushed^^

[@Paragon643]

The way they manage to do that is basically just pressure. Just like how you can stand on a closed full soda can without a problem but when it's empty and doesn't have pressure inside it will crumble under the load. If you have a thin wall tube that you put under a load it will want to move and deform. But if you cap it off and put some pressure into it, the pressure inside will will push against the tube walls and spread out the load across the whole thing and actively fight against it changing shape since that would require the gass to compress even further. I't like how the more you blow up a balloon the harder the outside of the balloon feels.

[@rileyjordan9072]

agreed. more to rockets than engines

[@allanshookphoto]

Yes, I have asked for this topic before. The mechanical engineering doesn't get nearly as much attention as the chemistry. All that expanding gas pushing on the diverging surfaces of the nozzle, and the injector plate, and then up through the... um, how does it all not blow itself apart and crush itself? The entire weight of the vehicle balancing on the tiny surfaces of the thrust bearings! The mechanical engineering is insane.

[@theOrionsarms]

It's all about the choosing the right shapes (and materials too) , for example a cylinder is very strong for axial forces, and a nozzle bell have the same shape and strength as a cathedral dome.

[@saadusmani78]

@@Paragon643 This could probably make for a short, but this definiely cannot be a full video

[@Oatmilk123]

Hey Tim, recently my team and I placed top 3 in a national aerospace highschool competition called StellarXplorers. I think it’s partly because of you that we succeeded with your immensely informational content. Keep up the great work! :)

[@idleeric8556]

👍🚀😎

[@Tech_Planet]

Excellent video about different types of rocket engines!

[@zuthalsoraniz6764]

16:00 There were some other (never flown) rocket designs that planned to reach orbit with just pressure-fed engines, like the German company OTRAG's design of a cluster of a huge number of mass-produced cheap rocket modules, and the Sea Dragon that planned to get past the mass ratio issues of being pressure fed with simple brute force of being absolutely huge.

[@UNSCPILOT]

Love the Seadragon design, such a monster of a rocket made of steel and brute force, it's a shame it never got a chance.

[@tarunantony1866]

Otrag would have had such complicated aerodynamics

[@sergeyanikin8326]

Amazing, definitely your best video to date! Can't believe it was almost an hour. Thanks to all people involved in producing and reviewing the content for the hard work that made it so easy to watch, understand and enoy!

[@zavevu]

The only problem is what will happen after the videos will reach perfection. They are definitely very very close. Let's see what Tim does then.

[@kellyfarrell1646]

The production quality on this channel is amazing! I think one day we will have variable expansion ratio combustion chambers and this will solve many issues like throttle ability, although of course, it’s anyone’s guess how material science and technology will evolve. Nevertheless this channel always sparks my creative mind and I appreciate the content.

[@danielhermanus6909]

I LOVE how this video works from the bottom up - from just opening a valve, where the recoil pushes back (which everybody knows and understands) to what if you do X Y and/or Z to improve. This is literally how engine development advanced, so it makes sense to teach it this way.

[@ThatGameGuyy]

wow. just wow. As an aerospace student I can attest to the succinctness and grace through which you've distilled weeks worth of my laboring over textbooks into a single, engaging, digestible, hour. I recently had an art history major friend school me on soviet rocket history.. ART HISTORY MAJOR. You truly are bringing space down to earth for everyday people. Thanks Tim, your impact will be profound.

[@brunoyuitinascimento3239]

As a aerospace engineering student I'm happy to see many of this videos, they help a lot to study some subjects. Thanks 💚💚

[@frosty-5727]

Br? Faz em que facul?

[@brunoyuitinascimento3239]

@@frosty-5727 ufabc

[@maximilianseifert5486]

This is such an amazing video. Thanks for all the hard work that you do Tim. Can't wait for the next Starbase tour!

[@rorygudka2474]

This is my new favorite video! The level of detail was exactly what I was looking for to understand the different engine types, and the graphics were amazing at helping visualize it all. Thanks for the incredible work!

[@michaelbotros5814]

This channel is honestly the most valuable thing in the entire internet

[@valentinmoeller]

That was a great video! Thank you!

[@mrboredj]

This is the first video which really gave me an intuitive feel for how the different cycles work, rather than just kinda understanding it academically. Really awesome.

[@timster5]

I know we don't get videos quite as often these days, but it's pretty obvious why. This is clearly years of research and knowledge condensed into less than an hour and I just want to say thank you for that. Thank you too your editors for the excellent animations and graphics. And although I'm not a channel member, I want to say thank you to everybody that can support you monetarily. Tim you're an absolute legend.

[@brettpatching]

This was wonderful Tim and Team!! Definitely bringing this level of complexity down to earth for everyday people.

[@StealthParrot]

Another amazing educational and fascinating video. The graphics are superb and really help simplify and visualize these extremely complex engine systems. Thanks Tim.

[@thinfourth]

Can you imagine the horror of discovery channel doing this

[@danrocketfan9606]

I love you teaching videos. Definitely brings space down to earth for us everyday people!

[@dzjad]

My kids (9 and 11) loved this. We had a great time pausing and talking it through.

[@JayAntoney]

Quite seriously - I have no idea how you do these videos. They are by far the easiest to understand and most information packed videos I watch. Hats off to you dude

[@GeorgeCrawley]

Tim, just imagine if Elon sent you up to the ISS on an Axiom mission with a film crew. Picture the sense of adventure you would bring to all of us sitting in our living rooms throughout the entire training and mission, every nuance and appreciation of the experience highlighted which others might have just taken for granted. Elon's over-arching goal of making people be excited to get up in the morning needs to be transmitted to the masses. It's not enough to achieve it, it needs to be documented as it unfolds. More so than just a standard biography, Elon needs someone to document the sheer breathtaking experience of how he has already brought our optimistic science fiction future into today's reality. Noone would do it better than you. I've been following your work since the start, so much so that you have made me a fan of all things Space. Your videos are always engaging, and the progress you've made over the years in quality is excellent - the epitome of Elon's iterative design philosophy. Your success in outreach has brought the dream of space travel to all the little would-be engineers and scientists the world over.

[@SuperSMT]

If anyone deserves a seat on Dear Moon, it's tim!

[@Usrthsbcufeh]

why tf u writing fan fics lmaooo

[@nickhowatson4745]

@@Usrthsbcufeh well now Tim is actually going to the moon so its even better than going to the ISS and not really fan fiction anymore. hes been chosen as one of the crew members for the DearMoon mission which is going to orbit the moon and is launching in the end of next year 2023

[@Usrthsbcufeh]

@@nickhowatson4745 but I’ll set a reminder for end of next year to see if u deleted ur comment lmaoo

[@calebj1145]

High quality, accurate, intelligent content in an accessible format. Exactly what I've come to expect from this channel!

[@darionz]

Again, the inspiration to continue my studies brought upon by this amazing channel is greatly appreciated! Thanks Tim and the team that made this video possible! 10/10

[@rhysdemazure4533]

I just noticed I've designed many tap-off engines, without even knowing it, thought it was a closed cycle. Great video! 👍

[@SimonGould1024]

Loving all these videos about how to get into space but would love to see some in-depth vids on once you are in space. Things like getting rid of excess heat, potential ways of artificial gravity, power sources for long durations, water/waste recycling, exercising, etc. Thanks.

[@JaySmith91]

I really liked how the equations were presented around 39:00. Including the variables in one color and their definitions immediately to the right in small text. Genius! I might start doing that whenever the situation calls.

[@FlorianBinsker]

It's a great presentation except for the equation being wrong in terms of units.

[@NickGobin]

Great graphics as always Tim! I particularly enjoyed the review of the simple (pressure fed) and really exotic engines (expander and tap off). And now I am really really looking forward to the episode on starting a rocket engine!

[@janedoe9940]

Fantastic video, Tim! I agree, it's your best video in terms of clarity and animations. I am able to follow it on 2x, which means it's incredibly well made. Congratulations! Now, I think we're all waiting for the "How to start a rocket" video :)

[@leeroychang]

Much Love Tim. Looking forward to getting through this! Thank you!

[@Mexican_Robobot42]

As always, thank you for a well-made video! You deserve all the support you receive and I’m happy for you on the point you’ve reached right now!

[@blenkiron1795]

Such a great video, as always of course! I love the way you start with the simplest cycle types instead of the complex ones, it really helps me understand and grasp why these engines are designed the way that they are, and why all that complexity is necessary. I also like how you discuss WHY some cycles are used instead of others: it is often overlooked in videos explaining specific cycles.

[@nightfox6738]

Tim I love the way you present mathematical equations. Most people just show the letters/symbols representing each term and tell you what it represents once, it's so helpful how every time you show the equation the labels are always there as a reminder. And your graphic design for it is so elegant. Great work as always!

[@niclewis7268]

The year is 2067, the first warp engines are being tested in humanities pursuit to other stars, and Tim Dodd explains exactly how it works as simply as 2+2

[@pluto8404]

_how to program a warp engine with 3 lines of python_

[@alwynwatson6119]

And in 2026 how the fuel cell powered cryogenic superconducting combined radial and axial flux electric motor fed rocket engines work.

[@-danR]

Or why it won't work. But first comes: "Why spin-launch won't work."

[@Effectlife]

The production on these videos is once again insane. I just watched a video of almost an hour, and I didn't notice time passing by this quickly. I felt like the video only just started. Well done, Tim & Team!

[@dharmasrisilva5997]

Tim thank you so much for putting up that animated diagram of the ox-rich turbopump at @29:04 instead of just the basic diagram like in your raptor engine video... it really helped me to understand it further.

[@munindramohanta2584]

wow, finished a 1 hr video in 2 hrs!! but boy do you learn a lot!!! This can easily be a Netflix special for geeks or on discovery +.I can only imagine the amount of research this needs!!

[@isaytheenay5961]

1 minute out, and already 49 comments. Wow Tim, You've come a long way. And we've been here for the ride from the beginning. Thank you for leading us all on this wild journey!

[@patrickgottschald1226]

OMG! Thank you Tim! Again one these very well done videos. And you still increased quality. Amazing, loved watching. I’m just sorry I can only 👍 it once. Looking forward to the next. Maybe electric engines like VSIMR or Hall thrusters.

[@alanrogers7090]

Thanks, Tim. You've cleared up some questions that I had floating around in my mind, though you've also opened some new "tracks" for my "train of thoughts" to pursue. As always, you are clear in your explanations and the animations really help as well.

[@TimbavatiLion]

Wow, i finally understood the different cycle types. And it gets a bit more obvious why the Raptor Engine is supposed to be so robust and maintenance-easy with the preburners running so cool.

[@jackmiller505]

One of your best yet, Tim. Awesome job working us up to more complexity!

[@sean_silvers]

The day has finally arrived!!! Thank you Tim! ❤

[@kevenbair7878]

I’ve been a Florida resident for 20 plus years but had never been to the visitor center, went yesterday! and this video is the perfect thing to watch after! Your the best dude!

[@faisolk]

Thank you for this video I've been lost in the last couple of days looking for how rocket engines are fed fuel and this really made it clear, i can't wait to know how rocket engines are started.

[@schlenbea]

Thanks Tim! This was so helpful and really cleared up a lot of questions I had! Can't wait for how to start a rocket engine!

[@codymills2393]

Outstanding work as always Tim! I definitely had to rewind quite a few times so that my small brain could absorb what you were saying but you really did make it understandable!

[@robmerrell1745]

How have less than 10% of the people that watches this video given it a thumbs up? I suck at KZbin so I don't know how to properly tag this. Dark Warrior said it best "I learned more about rocket science in the last 30 minutes than I have in 5 years, wow dude. You are good at teaching this."

[@geist96]

gotta say thanks again Tim. you got me hooked on these rocket videos and starship back in the day. And i have been following it all and watching as much as i can ever since. its really great to see the growth of it all and learn a little bit of how it all works.

[@aidanwansbrough7495]

This was incredibly well explained!! Thank you!

[@chrisfletcher8140]

I loved the vid, definitely back to what I love from your content. ❤🎉 Q: can you delve into the metallurgy aspects of rocket engines?

[@f205v]

THIS!

[@EverydayAstronaut]

I might be able to some day but a lot of that is closely guarded secrets unfortunately 😕

[@chrisfletcher8140]

@@EverydayAstronaut I'm not surprised to hear that - everything you do is brilliant and inspiring and I will love watching your next videos regardless!

[@dare2dan]

Great explanations and animations! Thanks Tim! I've been interested in rockets for years, but this is the first time I felt like I really understand the different cycle types.

[@danielallington5152]

Tim, you have done it again. You have paid it forward so well that it really shows I am able to understand so much better after you given your explanations, than anyone else that does deep dives on space.. I always come away not only with a greater understanding of the subject, but with also a greater respect for what and how you do it. Hats off to you!

[@iwayini]

Hey Tim, thanks for taking the time to make this video. Absolutely brilliant and great follow on from the Russian engine video. Keep up the great work of bringing space exploration down to a level we can all understand. I have learnt loads which in turn has upped my interest in rockets. Greetings from the UK.

[@delh1415]

Awesome, thanks for the incredibly well explained and well presented lesson on how rocket engines work, I will have to watch this several times to cement in some of the concepts :)

[@verndexter8822]

Yes!! Please do a series about this stuff!!! Your science and physics breakdowns are some of the best I’ve ever watched

[@FilAmStargazer]

EXCELLENT work. Really filled in the gaps that were in the orginal Raptor video. Nice emphasis on how the flow in the pre-burner doesn't go backwards and using that as a way to tie the discussions together

[@jonaspiccinotti5916]

❤️ Tim you are like most useful and entertaining civil servant considering how much knowledge you spread for free! You are the best

[@roguevoid5214]

This is such an awesome video Tim! Really appreciate all the efforts that you and your team put into this video, you're definitely bringing space down to earth for everyday people! Btw, I would love to watch an everyday astronaut video comparing JWST and Hubble.

[@Flowrazornapalm]

Coming back to this after a year. We definately need a video about the exotics, like SRB's, xenon/ion and nuclear

[@hangie65]

Excellent explainer of what is a very complicated subject. You did a bang up job not only of laying out the different type rockets engines, but also of conveying the advantages and disadvantages of each type of engines into accessible and understandable sections. Well done and keep up the great job!

[@saadusmani78]

As always, this video is well-informed and well-explained. Keep up the good work!👍

[@razorreaper8440]

This is great content for the space & rocket nerd in me for years now... and still counting. Keep up the good work 👏 👍 @ Tim

[@tekitrash]

Honestly, I really just like hearing you talk and explain things. Your pacing is really good, your accent is pleasant and your content is compact and concise while not being devoid of your own opinions or anecdotes that are interesting. Thanks for the great work Tim!

[@leomyers2016]

Really appreciate all the work you are doing for these in-depth looks at rocket building and flying!

[@joh5417]

Was soo excited. But still can't wait for the whole starbase interview. Thank you for the great work!!!

[@stephenmorrow5069]

Your hydrogen is undense has made my rocket explanations at work more memorable. People remember that because it comes off awkward and people remember that. I am doing what I can to bring space down for everyday people too with the stuff I learn from you and Scott Manley.

[@morkovija]

I love the density of information in this one. Basically a book condensed into a 55 minute goodness

[@Pamudder]

Thank you for this video. I have always found the turbopumps to be the most intrinsically interesting parts of a rocket engine and it is always great to learn more.

[@sniperdude21]

Thank you so much Tim for bringing us these moments! History in the making and I super appreciate your intense understanding with Elon. Amazing work, please keep it up! 👏

[@idbek]

This was fantastic - thanks! I learned a ton. So well done! Can’t wait for more! Q: How is the Raptor2 an improvement over version1?

[@galfisk]

It's got a lot fewer sensors and bolted flanges.

[@Deathven1482]

In addition to the previous comment, it also has more thrust and is simpler to manufacture!

[@flechette3782]

Excellent video! Extremely informative. Top notch!

[@raegune]

Wonderful explanations of complex concepts. The fact that you can make this topic digestible in the way you have fully demonstrates that your tagline of "bringing space down to earth for everyday people" isn't just lip-service. Thanks so much for doing what you do!

[@kaltenstein7718]

Your Videos are always so cool to watch, you dont notice the hour going by, because it is all so interesting. Can't wait for the Full Elon Interview!

[@pauldonovan4572]

I have a headache

[@mystifoxtech]

same

[@escthedark3709]

It's just rocket science

[@Nemxxi]

I never thought I could understand a rocket engine, until now. Thank you very much

[@scottgilliland2061]

Excellent video Tim, very informative as always. Keep up the great work and I look forward to your next video!

[@jukkiivi4282]

@EverydayAstronaut you didn't specify which orbit. Lunar Module Ascent Engine was pressure fed and it got Ascent Module on lunar orbit. It even managed it as a single stage to orbit.

[@jambay4785]

Was wondering if there was a way to have a trailing engine system that could use the exhaust from the main rocket to propel it separately, for launch to orbit, and then use small guidance (compressed gas) to achieve an LEO - OK that was just silly. But it seams there's some hope to use that heat/gas expansion energy from the launch engines.

[@spaceranger6573]

@Jambay I assume your talking about the main nozzle exhaust. In that case it probably wouldn't work due to having a rotating shaft running through the combustion chamber and nozzle throat which would be difficult to cool.

[@luckosteve12]

Awesome video as usual. Always dropping the knowledge for us space enthusiasts. Thanks for all the hard work you put into producing your great content.

[@MSheepdog]

Fantastic video. Your choice to start with the simplest engine and let each engine build on the knowledge worked really well, and the pacing left enough time for each new concept to sink in before moving on. I really feel like I understand the concepts at work in each of these engine types now!

[@SoumilSahu]

I've always had one gripe with your videos explaining rocket engines: FLUIDS FLOW from regions of high pressure to low pressure. PRESSURE DOES NOT FLOW, it is not a thing, it is a quantity. It doesn't really change the conclusions, but it can be confusing for a lay person. Incredible video otherwise!

[@NathanielStickley]

I cringed each time he said that.

[@stonefreak5763]

23:35 not a big mistake, but sadly the "°C" is missing at the temperature of the Combustion chamber Otherwise a very awesome Video tho.

[@jujenho]

Tim, your dedication is making many of your viewers amateur “rocket scientists”. I am old enough to have witnessed fhe space race since the beggining as a teenager, and been fortunate to have built a considerable first-class technical library on the subject. But I never stop being surprised to having learned something in all of your videos. Keep it up, there is more to learn.

[@starrynayt]

I saw 55 minutes and I thought this is too long but here I am smiling as I've learned something new about rockets. Thank you, Tim!