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The Soviet manned Lunar progrLK-1am, had 2 concepts to get Soviet Astronauts to the Moon

The N1 rocket, which never really worked at all, except for the 4th launch that went pretty well (It lasted over 100 seconds); Until they shut down the 6 core engines, and the fuel lines exploded due to the still hot engine, if the had separated the first stage early, and started the second stage, the launch probably would've worked, and the Soviets may have actually gotten to the Moon sometime in the late 70s early 80s (Which also probably would've kept the space race going). One really bad design (Other than the number of engines), was that, although it was more powerful than the Saturn V (10,200,000 lbs thrust vs 7,500,000) it was much less efficient (I bet you can guess why), and thus couldn't take as much to the Moon

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The UR-500k which was the better choice for the Soviet lunar program as it had much less engines, (And eventually turned into the Proton rocket family class we all know), I don't have much other info on it, so you'll have to dig stuff up yourselves :)

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The LK, which was the landing spacecraft for the N-1, which LK-1 held 1 person.

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Then there was the spacecraft LK-1, for the UR-500k which was a Lunar flyby spacecraft, and the spacecraft for both, and had 4 modules

The crew module which could hold 2 people

The ADU emergency engine unit

PAB equipment rocket system block (Service module)

And the RB Translunar injection stage.

Then the LK-700, which was the lander part of it which was a direct ascent lander. (There's not a lot of other info)

 

So what do you guys think the odds are that the Soviets could land humans on the Moon if they separated the first stage in the 4th flight properly or used the UR-500k instead of the N-1?

Edited by Spaceception
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Well first of all, you made an error in the number of people the LK could hold. It only held one cosmonaut.

Also, LK-700 was a direct ascent method that was the only use of the UR-500k. That means that the entire spacecraft would land on and lift off of the moon. I can't find very much information on it, but I doubt they considered it for very long. 

Apollo did have some direct-ascent plans too, but it was found that the lunar rendezvous method would be safer. 

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14 minutes ago, Panel said:

Well first of all, you made an error in the number of people the LK could hold. It only held one cosmonaut.

Also, LK-700 was a direct ascent method that was the only use of the UR-500k. That means that the entire spacecraft would land on and lift off of the moon. I can't find very much information on it, but I doubt they considered it for very long. 

Apollo did have some direct-ascent plans too, but it was found that the lunar rendezvous method would be safer. 

Thanks, I'll update it :)

Again, thanks, I also couldn't find much info on it.

The Nova rocket! Which I would've loved to see be built.

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It is easy to forget just how primitive the moon landings were by modern standards. 

The Apollo landers used two separate engines, one for descent and one for ascent. Why? They didn't have the technology for deep throttling, even with hypergolics. Nor could they reliably execute a drop tank design. Today, we would obviously use a single engine/engine cluster with separate tanks for descent and ascent and merely drop the descent tanks along with the landing legs. But they had to use two separate engines. 

If Apollo was done today, we would probably leave the command module unmanned during the lunar landing and use a single engine for lunar orbit injection, descent, ascent, and LEO transfer. 

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2 hours ago, Spaceception said:

The Soviet manned Lunar progrLK-1am, had 2 concepts to get Soviet Astronauts to the Moon

The N1 rocket, which never really worked at all, except for the 4th launch that went pretty well (It lasted over 100 seconds); Until they shut down the 6 core engines, and the fuel lines exploded due to the still hot engine, if the had separated the first stage early, and started the second stage, the launch probably would've worked, and the Soviets may have actually gotten to the Moon sometime in the late 70s early 80s (Which also probably would've kept the space race going). One really bad design (Other than the number of engines), was that, although it was more powerful than the Saturn V (10,200,000 lbs thrust vs 7,500,000) it was much less efficient (I bet you can guess why), and thus couldn't take as much to the Moon

_______________________________________________________________________________________________________

The UR-500k which was the better choice for the Soviet lunar program as it had much less engines, (And eventually turned into the Proton rocket family class we all know), I don't have much other info on it, so you'll have to dig stuff up yourselves :)

_______________________________________________________________________________________________________

The LK, which was the landing spacecraft for the N-1, which LK-1 held 1 person.

_______________________________________________________________________________________________________

Then there was the spacecraft LK-1, for the UR-500k which was a Lunar flyby spacecraft, and the spacecraft for both, and had 4 modules

The crew module which could hold 2 people

The ADU emergency engine unit

PAB equipment rocket system block (Service module)

And the RB Translunar injection stage.

Then the LK-700, which was the lander part of it which was a direct ascent lander. (There's not a lot of other info)

 

So what do you guys think the odds are that the Soviets could land humans on the Moon if they separated the first stage in the 4th flight properly or used the UR-500k instead of the N-1?

UR-500 would never have worked anyways since there was too much new stuff that needed to be made.

1 hour ago, sevenperforce said:

It is easy to forget just how primitive the moon landings were by modern standards. 

The Apollo landers used two separate engines, one for descent and one for ascent. Why? They didn't have the technology for deep throttling, even with hypergolics. Nor could they reliably execute a drop tank design. Today, we would obviously use a single engine/engine cluster with separate tanks for descent and ascent and merely drop the descent tanks along with the landing legs. But they had to use two separate engines. 

If Apollo was done today, we would probably leave the command module unmanned during the lunar landing and use a single engine for lunar orbit injection, descent, ascent, and LEO transfer. 

Would we? Altair used a conventional ascent and descent stage, and we don't know how to crossfeed, so drop tanks are pretty much impossible without lots of R+D.

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1 hour ago, sevenperforce said:

It is easy to forget just how primitive the moon landings were by modern standards. 

The Apollo landers used two separate engines, one for descent and one for ascent. Why? They didn't have the technology for deep throttling, even with hypergolics. Nor could they reliably execute a drop tank design. Today, we would obviously use a single engine/engine cluster with separate tanks for descent and ascent and merely drop the descent tanks along with the landing legs. But they had to use two separate engines. 

If Apollo was done today, we would probably leave the command module unmanned during the lunar landing and use a single engine for lunar orbit injection, descent, ascent, and LEO transfer. 

Having multiple engines gives you abort options in case one of them dies on you. 

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2 hours ago, Ten Key said:

Having multiple engines gives you abort options in case one of them dies on you. 

While the whole expedition depends on a single Apollo's main engine: to inject the Moon orbit, to correct it from 100 km to 15 km, to intercept the lunar ascent stage, to run home, to correct trajectory two or three times.
Also two fuel and engine systems on LEM don't look like more reliable decision than only one.

Edited by kerbiloid
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58 minutes ago, kerbiloid said:

While the whole expedition depends on a single Apollo's main engine: to inject the Moon orbit, to correct it from 100 km to 15 km, to intercept the lunar ascent stage, to run home, to correct trajectory two or three times.
Also two fuel and engine systems on LEM don't look like more reliable decision than only one.

Actually, they had another engine, the LEM descent engine, to do burns. That's what they did in Apollo 13.

 

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38 minutes ago, fredinno said:

Actually, they had another engine, the LEM descent engine, to do burns. That's what they did in Apollo 13.

 

Yes, but just because Apollo 13 performed a non-stop flyby around the Moon, and only several small corrections were required.
If their accident happened on a Lunar orbit, not sure if LEM engine would be enough to return.
(Interesting. I need to calculate this later.)

Edited by kerbiloid
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5 hours ago, sevenperforce said:

It is easy to forget just how primitive the moon landings were by modern standards. 

The Apollo landers used two separate engines, one for descent and one for ascent. Why? They didn't have the technology for deep throttling, even with hypergolics. Nor could they reliably execute a drop tank design.

The Apollo LM used staging to save weight. A single-stage lander would have to be much larger or would have a much smaller payload fraction. It's the same issue where an SSTO will always have to be bigger and heavier than an equivalent MSTO.

The Russian LK was single stage (it had two sets of engines, but those were for redundancy). It used a crasher stage landing technique where the Blok D stage performed most of the descent burn and was dumped just before the final descent. This allowed the LK to land with its tanks nearly full, so it didn't need two stages.  On liftoff, it only left a basic frame with the landing legs on the ground. It also had settling rockets to push the legs into the ground after touch down.

There is a lot of info out there about the Russian LK and N1 if you look properly.

 

Quote

Today, we would obviously use a single engine/engine cluster with separate tanks for descent and ascent and merely drop the descent tanks along with the landing legs. But they had to use two separate engines. 

No we wouldn't. The Constellation Altair design was two-staged also. Constellation remains the latest NASA lunar mission reference.

Quote

If Apollo was done today, we would probably leave the command module unmanned during the lunar landing and use a single engine for lunar orbit injection, descent, ascent, and LEO transfer. 

That architecture is called Direct Ascent and it requires a much larger lander. This isn't KSP, the dV descent and ascent requirements are actually pretty high.

Altair used the descent stage for LOI and descent, the ascent stage for ascent and RV, and the Orion would have done the TEI burn, just like Apollo. That architecture is called LOR (Lunar Orbit Rendezvous) and remains the most efficient architecture in terms of mass, because the laws of physics haven't changed since Apollo.

I agree that a reusable single stage lander that would stay at EML-1 would be a good option for a long-term infrastructure.

Edited by Nibb31
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1 hour ago, kerbiloid said:

While the whole expedition depends on a single Apollo's main engine: to inject the Moon orbit, to correct it from 100 km to 15 km, to intercept the lunar ascent stage, to run home, to correct trajectory two or three times.
Also two fuel and engine systems on LEM don't look like more reliable decision than only one.

As you say, the SPS engine was used several times during the flight, so a malfunction would have been detected before separation from the LM. If that happened, the landing would be aborted and they would use the LM engine on a free-return trajectory, like Apollo 13. The chances of the TEI (Trans-Earth Injection) burn failing, after successfully doing the LOI (Lunar Orbit Insertion) and several trajectory corrections were small. Apollo also had an overpowered RCS which carried enough dV to perform a series of TEI burns.

If the LM descent stage malfunctioned, they would abort with the ascent stage, like on Apollo 10.

The only burn that didn't have any backup at all was the LM ascent. This was identified as one of the most critical items in the mission, so was engineered to be as simple and failure-proof as possible.

Edited by Nibb31
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Back on track, more that its technological shortcomings, the N1 stretched the Soviet logistics and supply chain, with parts built in Moscow and transported by train to Baikonur for final assembly. There were no test facilities at Baikonur, and the program was under constant pressure, so the only actual test of the assembled rocket was the launch. That explains the dismal failure rate.

In the end, even if the N1 had been successful, they were still several years behind Apollo. At best, they could have landed on the Moon in the mid-to-late 70s, with much more modest capabilities and much higher risk. The Soviet mission profile was much more dangerous. The LK had limited life support and could only spend an hour or two on the lunar surface. If the cosmonaut had been incapacited in any way, there was no one to help him. Also, the LK couldn't dock with the LOK, it had a sort of hook-and-grid latching system and the cosmonauts transferred by EVA, which was risky.

I don't think the UR500 solution, which was Direct Ascent, would have been viable. It would have required a much larger rocket than the N1 or the Saturn V (like the Direct Ascent Apollo would have required Von Braun's Nova rocket), which would have put even more pressure on the program.

Edited by Nibb31
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6 hours ago, fredinno said:

UR-500 would never have worked anyways since there was too much new stuff that needed to be made.

Would we? Altair used a conventional ascent and descent stage, and we don't know how to crossfeed, so drop tanks are pretty much impossible without lots of R+D.

Drop tanks has been used on fighter planes since WW2,
The problem with cross feed on orbital rockets is the amount of fuel who has to be piped and pumped and switching tanks without interrupting the flow. 
An small pressure feed engine is far more like normal fuel systems than an launcher. 
It would be possible to use one engine with tanks on the leg structure you dropped, issue is that this would probably not be much lighter. and you would loose the benefit of dropping decent stage if anything went wrong during decent. 

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9 hours ago, fredinno said:

UR-500 would never have worked anyways since there was too much new stuff that needed to be made.

Also, sotka family on which UR-500 was based was not man-rated. Even todays Proton is still not man-rated. 

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15 hours ago, Nibb31 said:

The Apollo LM used staging to save weight. A single-stage lander would have to be much larger or would have a much smaller payload fraction.

The Constellation Altair design was two-staged also. Constellation remains the latest NASA lunar mission reference.

[Single-engine] architecture is called Direct Ascent and it requires a much larger lander. This isn't KSP, the dV descent and ascent requirements are actually pretty high.

Not quite. The LOR lander carried two engines down, leaving a third engine in orbit with its own fuel tanks. I'm saying to keep the LOR approach, but use the same engine for all three burns. Separate fuel tanks for the trip to Earth stay with the command module in orbit. 

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3 minutes ago, sevenperforce said:

Not quite. The LOR lander carried two engines down, leaving a third engine in orbit with its own fuel tanks. I'm saying to keep the LOR approach, but use the same engine for all three burns. Separate fuel tanks for the trip to Earth stay with the command module in orbit. 

That's still LOR because it requires a rendezvous in lunar orbit to refuel your LM/CSM. The difference is that you carry a much heavier LM to the surface and back to orbit, which requires more propellant. It also means that you have no backup plan if something goes wrong with the refueling.

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1 hour ago, Motokid600 said:

Todays proton, but Proton DID have a manned mission did it not?

ur500l1.jpg

proton launched several TKS spacecrafts, with the escape tower attached to the VA (they even did launched some VAs without the FGB two VA capsules at a time, but they always flew unmanned :) - cosmonauts only entered TKS in space while it was docked to a salyut space station - but it never made a manned launch or reentry)

the VA was an autonomous apollo shaped capsule, with it's own service module engines in the 'nose', the escape tower was mated above this service module. the VA could be in addition launched attached to a FGB giving extra propulsion, solar panels, docking ports and living areas., forming the whole TKS spacecraft.

 

ultimately, the only thing that really was kept from tks is the FGB. (modified versions used as modules for MIR and ISS)

Edited by sgt_flyer
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2 hours ago, Nibb31 said:

That's still LOR because it requires a rendezvous in lunar orbit to refuel your LM/CSM. The difference is that you carry a much heavier LM to the surface and back to orbit, which requires more propellant. It also means that you have no backup plan if something goes wrong with the refueling.

That was my point; it's not a Direct Ascent. Still a LOR.

But why would the LM be heavier? It should be substantially lighter. It doesn't have to carry a second engine. In fact, it would be virtually identical to the LM of Apollo, minus the weight of the ascent engine. Meanwhile, the orbiting command module is much smaller, containing only return-trip fuel, return-trip consumables, and the re-entry capsule. So the overall launch mass is considerably lower. Compared to Apollo, you save on the weight of an entire pressurized command module, an entire engine, and part of the descent fuel. 

45 minutes ago, Panel said:

I liked the crasher stage on the LK. It seemed like a very kerbal way of doing things.

lkprof.gif

 

Now, if that crasher stage could carry enough fuel to boost itself back into orbit....

Actually, if you gave a Dragon V2 external tanks, I'm fairly sure that such a configuration could manage a manned moon landing and return with a Falcon Heavy and a Dragon V2 alone. 

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I frequently use crasher stages in KSP since there is no real ability to plan missions except to fly them (even with a dv map, you need some slop), and if the transfer stage gets you there with propellant remaining... I'm gonna use it.

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21 hours ago, kerbiloid said:

Yes, but just because Apollo 13 performed a non-stop flyby around the Moon, and only several small corrections were required.
If their accident happened on a Lunar orbit, not sure if LEM engine would be enough to return.
(Interesting. I need to calculate this later.)

No, it doen't have enough to get out of lunar orbit. You need a rescue mission for that, but the time between orbital insertion and LEM detachment, or LEM docking and lunar orbital ejection is a small fraction of the total mission time.

3 hours ago, Panel said:

I liked the crasher stage on the LK. It seemed like a very kerbal way of doing things.

lkprof.gif

 

The Orion/Boeing proposal used the same thing with the SLS upper stage and its 4-man reusable lunar lander- you'd dock the EUS/ICPS to the back of the lander, use the remaining fuel to do most of the descent, and reusing the ascent/final descent stage.

2 hours ago, sevenperforce said:

That was my point; it's not a Direct Ascent. Still a LOR.

But why would the LM be heavier? It should be substantially lighter. It doesn't have to carry a second engine. In fact, it would be virtually identical to the LM of Apollo, minus the weight of the ascent engine. Meanwhile, the orbiting command module is much smaller, containing only return-trip fuel, return-trip consumables, and the re-entry capsule. So the overall launch mass is considerably lower. Compared to Apollo, you save on the weight of an entire pressurized command module, an entire engine, and part of the descent fuel. 

Now, if that crasher stage could carry enough fuel to boost itself back into orbit....

Actually, if you gave a Dragon V2 external tanks, I'm fairly sure that such a configuration could manage a manned moon landing and return with a Falcon Heavy and a Dragon V2 alone. 

No, the reason seperate stages work for landers is the same reason staging is useful for orbital rockets; you drop the extra dry mass.

1 hour ago, tater said:

I frequently use crasher stages in KSP since there is no real ability to plan missions except to fly them (even with a dv map, you need some slop), and if the transfer stage gets you there with propellant remaining... I'm gonna use it.

Just use mods to calculate the DV. :P

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I use KER, so I have a pretty good idea, but I don't use the stock sized kerbol system, and even with a dv map, I need some slop. I'd design in contingency anyway.

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