Why Does SpaceX Use 33 Engines While NASA Used Just 5?

Many thanks to Kiwi Co for sponsoring today's video. If you have seen any of the videos of the Apollo launch or even the videos of the launch of the new Emis. You will no doubt be familiar with the shot of the huge F1

engines

at the SAT launch. 5 the four rs25

engines

and boosters on the SLS rocket as they leave the mobile launch pad now compare it to the SpaceX Starship and the super heavy booster with its 33w engines at liftoff and you might be wondering why they need 33 engines smaller when the satin and SLS only had four or five respectively plus a couple of thrusters, now yes, there is a difference in thrust, the SpaceX Starship with its super heavy thruster generates twice the thrust of the sattin 5, but the objective end of the new timus mission is the same whether they are using the Starship or NASA's SLS and that is taking the lander with a human crew and placing it on the surface of the moon and then bringing them home again.

The Apollo program did that six times in the 1960s and 1970s in In fact, back then, the Apollo program and the later Skylab program launched 13 satin fives that included unmanned test flights Apollo four, five and six, and

used

a total of 65 dying F1 engines with a 100% success rate, although all ended up in the Atlantic. because they were designed to be

used

once and then discarded, compare this to the Spax Starship and the super heavy booster which over time should be completely reusable similar to the SpaceX Falcon 9 and the Falcon heavy and this is where the two rocket systems diverge on separate paths satin 5 was the first and so far only rocket that took men beyond low earth orbit, but satin 5 did not come out of nowhere, it was a development of the rocket family Jupiter, a research and development vehicle that was part of the Redstone Rocket family, which itself was an intermediate-range ballistic missile in the 1950s, although it was used for space research like the missile Soviet R7 ballistic missile that put Sputnik into orbit.

The US military's ballistic missile agency designed the Jupiter. Under the direction of Verna Von Brown, who during World War II was the lead scientist and developer of the German V2 rocket as part of Operation Paperclip Von Brown, 1,500 scientists and several unused V2s were brought from Germany to the United States after the World War. II to help develop US rocket technology but they were tightly controlled on what they could and couldn't do, that changed in 1957 when the Soviets launched Sputnik 1 on an R7 ICBM, this really got on the nerves to the Americans because if the Soviets could put a satellite into orbit and then they could place a nuclear weapon anywhere in the US thereafter Von Brown was tasked with creating a new heavy rocket that he would base on Jupiter; in fact, she referred to Jupiter as a childish Saturn. and a Jupiter marine rocket was used to launch the first American Explorer 1 satellite into orbit in 1958, to match what the Soviets had done with Sputnik the previous year.

From 1959 to 1962, the Marshall Space Center, under the direction of Von Brown, designed a series of Saturns. Rockets the first three-stage version was for Saturn C3 this would be a three-stage vehicle that could lift 45,000 kilos to low Earth orbit and send 18,000 kilos to the Moon by translunar injection the design began with two F1 engines for the first stage, but by 1961 this had been increased to three, as it was thought that two or three launches might be required to achieve a single landing on the moon, so a larger rocket was planned that could lift a heavier payload: this would be the Saturn C4 which would use four F1 engines and only need to do two launches for each moon landing, but why not do it with a single launch rocket and save the cost of having two launches and two rockets?

Then the C5 was planned, this would use five F1 engines for the first one. stage five J2 engines for the second stage and a single J2 engine for the third stage and would be the design that would take man to the moon for all the Apollo missions, since we are talking about rocket engineering, perhaps it is worth noting. that understanding about rocket engines and how they work and the scientific and technical things is what I love doing on this channel. My journey to where I am today began in 1975, when I was 13, after seeing a friend buy an electronics kit for Christmas that fascinated me.

I liked it so much I wanted my own so I sold my beloved train set and bought my own electronic equipment and managed to find some photos of the same one I had in 1975 which propelled me into electronics and then computing and then my own repair electronics. then to a computer business, then to a video production business and then to YouTube where I've been for the last 8 years and it all started with that electronics kit so I got a set of Kiwi Co boxes to show to my 10 year old daughter how things work and she can put them together herself with my help is something that really resonated with me and my learning experience, kiyo, is about learning how to make things like core themes fun and interesting.

We have an illuminated planetarium that projects stars and constellations. on a ceiling or wall in a dark room so you can know what they look like and where they are from the comfort of your home when you can't go out, everything is included in the box so there is nothing else to find and all the projects. They're fun and teach skills in things like electrical and mechanical assembly knowledge and how to go from a kit of flat parts to a fully functional 3D product. The boxes are expertly designed to be fun and easy to put together and are available for a variety of angels from newborns to us adults, so you don't need to feel left out when the kids are having fun.

You can

just

buy individual boxes to see what they're like or sign up for monthly delivery once you're ready. To help support the channel, act now and you can get 50% off your first box of a monthly kiwico subscription when you visit kiwico.com. Curious Droid and use the code Curious Droid. But as time went on and more tests were performed, a problem arose. It was revealed that with the F1, the F1 engine had been developed to replace the E1 engine, which was created to meet the 1955 US Air Force requirement for a very large rocket engine,

while

the E1 worked, it was seen as a technological dead end and the F1 was its even bigger replacement in the mid-1950s, there was a spirit of making everything as big as possible: bigger planes, bigger buildings, bigger bombs. big, the biggest cars, and so it was with rocket engines, but at that time there were no rockets. but it could use such a large engine, so development stopped;

However, when NASA was created, it could see that there might be an application for a very large engine and contracted with the rocket to complete its development; However, early tests showed that severe combustion instability could sometimes lead to catastrophic failure, this was caused by a reaction of around 4 khz with harmonics of up to 24 khz in the combustion chamber and could be as strong as which could cause the combustion chamber to fail, but were also very intermittent and varied in strength. something that had been seen in smaller engines but with the large size of the F1 it became a very big problem, the problem was so serious that it took almost two years to find a solution and threatened to end the Apollo program if it could not be solved .

Fixed: The fix was found by detonating small black powder explosive charges in a tube

while

the engine was running. This would show how powerful oscillations moved through the chamber and possibly how to stop them in the end after many design iterations created through testing. and error deflectors were used on the injector plates to dampen oscillations. This was so successful that the engine was stable enough but automatically damped any artificially induced instability within a tenth of a second and produced a very reliable engine in the meantime in the Soviet Union. Engineers had also encountered the same instability in larger rocket designs.

Their solution was to split the engine into a single turbo pump that fed multiple smaller combustion chambers, usually four if you look at the Rd 107 engines used in the R7 rocket that launches Sputnik and Sputnik. Many others later will see four boosters strapped to the base of a rocket, each with four nozzles, but in reality each of them is

just

one engine with four separate combustion chambers and four nozzles, and that's how the Soviets solved the problem. instability problem they would have. He later used the same idea of ​​many smaller engines for his version of a lunar rocket which will be more powerful than the satin 5 and will be known as the N1.

This design required 30 smaller rocket motors but they were more efficient than the F1 engines with a specific impulse of 331 seconds compared to the F1's 263. They also used a different way of steering the rocket compared to the sattin 5 in the sattin 5. The four outboard motors used hydraulically driven gimbals to move the motor and steer a rocket into takeoff. The N1 rocket used a method called differential threat thrust. Here all the engines were fixed in place and increased or decreased thrust on one side of the rocket compared to the other to steer it. The problem here was that they had to rely on early control.

The computer called the cable to maintain the correct thrust balance. If one engine on the left side failed, its counterpart on the right side would have to shut down to maintain thrust balance. This meant that if you had two or more engines, you would have to turn off four engines, six or eight instead of just two, three or four, one of the main reasons the design used so many smaller engines meant that if you missed one or two, the launch would not be compromised if the same thing happened to a Satin 5 and one of the five F1 engines were lost, it would lose 20% of its thrust immediately and would probably mean the mission would have to be aborted, as it might not have the thrust needed to reach the correct orbit unless it was anyway very late and close to the closure of the first stage, however, due to budget constraints and the lack of testing facilities for a rocket.

As big as the M1, only about one in six engines was tested, the rest taken straight from the factory. and installed on the rocket, the flight itself would be a test very similar to that of SpaceX and its methodology of moving fast and breaking things. The first four launches of the N1 all failed, some failing due to fuel. Plumbing failures caused by an engine shutdown and others caused by the engines failing, but both led to a failure of Cascade and the loss of the entire rocket. the untimely death of Sergey Corello in 1966, the lead engineer and scientist who, unbeknownst to the US, was literally the man who controlled everything related to the M1.

So it was a huge shock to the Soviet lunar program that this left his vicious deputy in charge of the mission, but he lacked Cello's political astuteness about the Soviet system and influence, and was also said to be a bit of a heavy drinker. in 1972 and that he had already lost. the race to the moon to the Americans with the failure of the fourth in1 rocket the Soviet Communist Party lost patience with the N1 program and canceled it now, some 50 years later, SpaceX is using a similar type of design for the Starship heavy booster that uses 33 Raptor engines, this is nothing new, the Falcon 9 uses nine Merlin engines and the Falcon heavy uses three boosters each with nine engines, so there are 27 engines in total and these have become the most advanced launch systems. reliable of history, but there is another reason why they use so many smaller engines instead of just a few larger ones and that is reuse, the sattin 5 with its F1 engines was created at a time when reuse was not seen as an option, it wasn't like they couldn't be used, they could have been. condition and were rated for 10 reference flights, the problem was recovering them in one piece on the 1970s rocket.

Dy did studies on a version of the F1 that included a reusable Saturn S1C return first stage, but it came no further While we now live in a world where the old form of space flight is considered wasteful because little or no rockets and spacecraft are reused, Elon Musk, CEO of SpaceX, has said that you wouldn't buy a car and use it to just one trip and then throw it away, so why would you do the same with a rocket? One of the main features of SpaceX's rocket designs was making them reusable like the Falcon 9, which can land on the launch pad or other landing zone after having beenmade. developed its payload to put it into orbit and that is why the super heavy booster needs so many smaller engines first to get the enormous amount of thrust on takeoff twice from Saturn, but when it comes to landing the now practically empty booster on The Earth requires much less thrust than it had when taking off in the first place, if we look at a super heavy booster, its long weight is 3,600 metric tons. 3,400 is fuel, leaving only 200 tons for the dry weight of the booster plus some fuel for landing, so the thrust required to slow down to landing speed is not much compared to when it took off.

If the superheavy had, say, five F1-equivalent engines with 700 metric tons of thrust, then only one engine would be too powerful for landing, since the F1 engines could not reduce their power, even if the engine had a controlled of acceleration, it would have to drop below 40%, something that only the most modern engines that have been designed with that in mind can do during the final landing of the 13 super-heavy booster engines are used to brake from high altitude and approximately 1200 km per hour, which is then reduced to three as it approaches the ground as the speed drops below 10 kmph for its final landing, having the ability to use many engines. slowing down The Descent and then switching to just three and using your throttle control and gamble to guide the booster down allows it to land and then be reused.

Large engines are also more expensive to manufacture. F1 engines were effectively hand-made with thousands of welds holding them together. Along with new manufacturing techniques today the number of parts needs can be 80 to 90% lower with Raptor engine production running approximately one per day and when mass production levels are reached it is expected that the cost of Raptor engines to be less than $250,000 a piece. The Rocket Ding F1 engines were a simple design. and relatively cheap to produce, considering the large amount of labor required to build them, they had an estimated cost equivalent to $15 million in today's money, assuming 40 were purchased at a time and 10 to 12 were manufactured per year in total. 98 were produced and delivered to NASA.

In total, although each F1 was only going to be used once for launch and then abandoned in the Atlantic, it was then classified for 10 reference flights in testing, two engines were used, one performed 20 tests for a total of 2256 seconds. and the other during 34. tests and 2,913 seconds during actual flights, they were only used for between 159 and 165 seconds, if they had been able to return to Earth safely then they could have been reused many more times in all

spacex

models, the Using many engines not only gives you the thrust you need. requires takeoff but also control to land the booster or Starship back to Earth on another planet or Moon if necessary.

It's also a bit ironic that NASA's SLS rockets are using the rs20 25 engines from the space shuttle they designed. Great lengths to make it reusable and are now being used for one-way trips before being dumped into the Atlantic in the same way as their F1 predecessors and now the reusable part of the SLS rocket are solid rocket boosters, just like in the days of the shuttle, which are much simpler in construction, so you're keeping the simple things and ditching the complicated and expensive parts. Maybe the best brains in n are already gone and I work for SpaceX because it's starting to look like that so thanks for watching and I hope you enjoyed the video and if you did please like share and subscribe and many Thank you to all of our sponsors for your continued support.