Is it possible to do a direct accent mission to the moon?

[VictoryNeverFail]

I know the Soviets designed a spacecraft to do this, but it wasn't built do to funds. But is it actually possible to afford a direct accent mission to the moon, and if it is, do you think someone will actually use this method to get to th moon and back? 

Personally, I don't think they will, but I wanna see what you guys have to say about it.

[magnemoe]

1 minute ago, VictoryNeverFail said:

I know the Soviets designed a spacecraft to do this, but it wasn't built do to funds. But is it actually possible to afford a direct accent mission to the moon, and if it is, do you think someone will actually use this method to get to th moon and back? 

Personally, I don't think they will, but I wanna see what you guys have to say about it.

The N1 moon program would use and landing module who would dock back with capsule in lunar orbit.
US had an consent based on direct accent, it would require an significantly larger moon lander and an Nova rocket or similar rather than Saturn 5
http://www.daviddarling.info/encyclopedia/N/Nova_rocket.html

 

[DDE]

17 minutes ago, VictoryNeverFail said:

I know the Soviets designed a spacecraft to do this, but it wasn't built do to funds

No, it was because Korolev mustered all of his political capital among the artillery/rocket branch and was able to cancel the rival Moon program by Chelomei, an invader from the Ministry of Aviation.

There’s really not much more to it being cancelled than Korolev’s tribalism and possessiveness (also a property of Max Faget - see rejected Martian Apollo design), aside from an irrational aversion to UDMH-NTO, and Glushko trying to build a SpaceX Raptor engine half a century early.

Edited May 29, 2019 by DDE

[kerbiloid]

Iirc, one of proto-7K was direct ascent, too; and that's why the Soyuz toilet module interior is oriented perpendicularly to the capsule interior (to let them sit on the couch and use the toilet in the gravity field), and why its airlock door is placed at such strange place and angle (to let them get down to the lunar stairs).

Of course, LK-700 was direct-flight only, without rendez-vous.

41 minutes ago, DDE said:

it was because Korolev mustered all of his political capital among the artillery/rocket branch

That's ironic that really working ICBM and SLBM were created by Chelomei-Makeev-Yangel/Utkin&Utkin, when Korolev had been relieved of military programs.

Also it's ironic that a failed ICBM R-7 became a common space launch vehicle, while originally it was used for that just casually, while the warhead was failing even more.

41 minutes ago, DDE said:

aside from an irrational aversion to UDMH-NTO

Maybe he just  knew his personel better...

Edited May 29, 2019 by kerbiloid

[kerbiloid]

_(multipost)

Edited May 29, 2019 by kerbiloid

[tater]

SpaceX seems to think so.

Of course they will be refilling the spacecraft in orbit first.

[magnemoe]

1 hour ago, kerbiloid said:

Iirc, one of proto-7K was direct ascent, too; and that's why the Soyuz toilet module interior is oriented perpendicularly to the capsule interior (to let them sit on the couch and use the toilet in the gravity field), and why its airlock door is placed at such strange place and angle (to let them get down to the lunar stairs).

Of course, LK-700 was direct-flight only, without rendez-vous.

That's ironic that really working ICBM and SLBM were created by Chelomei-Makeev-Yangel/Utkin&Utkin, when Korolev had been relieved of military programs.

Also it's ironic that a failed ICBM R-7 became a common space launch vehicle, while originally it was used for that just casually, while the warhead was failing even more.

Maybe he just  knew his personel better...

And you are correct lk-700 was direct accent. 
http://www.astronautix.com/l/lk-700.html

http://www.astronautix.com/u/ur-700.html
or to kerbal 

[kerbiloid]

9 minutes ago, magnemoe said:

And you are correct lk-700 was direct accent. 
http://www.astronautix.com/l/lk-700.html

Also photos
http://novosti-kosmonavtiki.ru/forum/forum9/topic9885/?PAGEN_1=18

[ZooNamedGames]

The Saturn Nova was an enlarged Saturn design that could've hefted a direct ascent lunar lander which would've flown directly to the moon, landed, took off, and returned to Earth.

One of the reasons the Apollo Service Module's Service Propulsion Engine is so large- is due to the late shift in mission architecture. Initially planned to be Moon Direct which would've utilized the massive Saturn 8 Nova- however due to a late proposal by Dr. John Houbolt to Robert C. Seamans, the associate administrator of NASA. He proposed the concept of having a smaller rocket lift two spacecraft on one rocket instead of multiple as the Soviet's intended with Earth Orbit Rendezvous (EOR). Instead, launch two vehicles, one that could carry the crew and return to Earth and a lighter lander optimized solely for landing on the moon, and nothing else. Allowing the launch vehicle to carry ultimately less mass than a direct launch vehicle and requiring a single launch as opposed to the Soviet's multilaunch structure.

[kerbiloid]

And the direct ascent Gemini project.

https://vintagespace.wordpress.com/2011/12/22/taking-gemini-to-the-moon/

(Not to be confused with a separate lightweight Gemini lander)

[Bill Phil]

Direct ascent is possible.

Indeed there was a concept for a two man direct ascent mission that could use a normal Saturn V.

As for practicality... well, EOR and LOR generally have advantages. I lean towards EOR, but LOR has advantages as well.

[DDE]

2 hours ago, tater said:

SpaceX seems to think so.

Of course they will be refilling the spacecraft in orbit first.

 

2 hours ago, kerbiloid said:

Iirc, one of proto-7K was direct ascent, too

SpaceX should get in line. Here’s one of the two 21K tankers for the DA Soyuz mission:

Other DA Soyuz designs used an inflatable collar separating the SM from the CM, and other oddities.

[razark]

Is it possible?  Of course it is.  As long as it doesn't violate the laws of physics and you can get someone to fund it, anything is possible.

Practical?  That's a completely different question.

[VictoryNeverFail]

5 hours ago, magnemoe said:

The N1 moon program would use and landing module who would dock back with capsule in lunar orbit.
US had an consent based on direct accent, it would require an significantly larger moon lander and an Nova rocket or similar rather than Saturn 5
http://www.daviddarling.info/encyclopedia/N/Nova_rocket.html

 

I'm not talking about the N1 I'm talking about the Universal Rocket.

Ok guys, I know direct accent is possible in reality, I know what the saturn 8 nova is, what I'm asking is it possible to properly fund such an enormous and powerful rocket. And if it is a practical to do direct accents instead of Apollo style or however other way you can land on the moon.

[Bill Phil]

20 minutes ago, VictoryNeverFail said:

I'm not talking about the N1 I'm talking about the Universal Rocket.

Ok guys, I know direct accent is possible in reality, I know what the saturn 8 nova is, what I'm asking is it possible to properly fund such an enormous and powerful rocket. And if it is a practical to do direct accents instead of Apollo style or however other way you can land on the moon.

The Saturn V was capable of direct ascent if you are willing to reduce mission requirements (fewer crew members, less payload on the Moon, and so on).

As for building rockets big enough... well the big limitation was the size of the Michoud assembly plant for the USA, which limited the stages to 10 meters in diameter. However clustering may have been possible, like adding Titan SRBs or even some new LRBs. One of the Saturn V modification proposals even proposed something like that.

It’s generally considered impractical since for the same launcher you can get better performance with Apollo-style.

[ZooNamedGames]

1 hour ago, Bill Phil said:

The Saturn V was capable of direct ascent if you are willing to reduce mission requirements (fewer crew members, less payload on the Moon, and so on).

As for building rockets big enough... well the big limitation was the size of the Michoud assembly plant for the USA, which limited the stages to 10 meters in diameter. However clustering may have been possible, like adding Titan SRBs or even some new LRBs. One of the Saturn V modification proposals even proposed something like that.

It’s generally considered impractical since for the same launcher you can get better performance with Apollo-style.

I cannot source this, and it’s just something I remember, so consider it hot air- but I recall some concept of adding cranes to the roof of the VAB to assemble larger and taller rockets that would exceed the limitations of the VAB (namely the roof and the doors). 

[kerbiloid]

Spoiler

They should use Hangar Extender (Extended)

 

[cantab]

The Gemini Direct Ascent proposal is the best evidence that a direct ascent lunar landing could be affordable. Since it would have used the same Saturn V rocket that Apollo did, just with a different spacecraft on top, chances are it would have cost about the same. However the Apollo CSM and LM were more capable than any Gemini-based lander would have been. (And more enjoyable to fly - Gemini was notoriously cramped.)

Refueling in LEO isn't direct ascent, it's Earth Orbit Rendezvous. If you're only transferring fuel you at least don't need to worry about assembling your lander in orbit, but you still have many of the other drawbacks to an EOR approach. Spacecraft are only certified for a limited amount of time in space and delays to the fuel tankers could be an issue. SpaceX's starship is built to handle a Mars mission lasting a few years anyway, so delays in LEO are proportionately less of an issue.

Edited May 29, 2019 by cantab

[tater]

34 minutes ago, cantab said:

Refueling in LEO isn't direct ascent, it's Earth Orbit Rendezvous.

Yes and no. EoR was usually used with the notion of assembling a spacecraft in Earth Orbit, not refilling one. Starship also changes the whole direct ascent paradigm by not only returning some tiny % of the rocket (the capsule on top).

5 hours ago, VictoryNeverFail said:

Ok guys, I know direct accent is possible in reality, I know what the saturn 8 nova is, what I'm asking is it possible to properly fund such an enormous and powerful rocket. And if it is a practical to do direct accents instead of Apollo style or however other way you can land on the moon.

One answer is "anything is possible that is technically possible." The realistic answer is "no." Why? That experiment was done, NASA had a bigger % of the budget than it has had since, or will ever have, and Direct Ascent was too expensive then. Other space programs from a money standpoint don't really matter, all of them combined spend about what NASA new, tiny (by comparison to Apollo) budget.

[magnemoe]

33 minutes ago, cantab said:

The Gemini Direct Ascent proposal is the best evidence that a direct ascent lunar landing could be affordable. Since it would have used the same Saturn V rocket that Apollo did, just with a different spacecraft on top, chances are it would have cost about the same. However the Apollo CSM and LM were more capable than any Gemini-based lander would have been. (And more enjoyable to fly - Gemini was notoriously cramped.)

Refueling in LEO isn't direct ascent, it's Earth Orbit Rendezvous. If you're only transferring fuel you at least don't need to worry about assembling your lander in orbit, but you still have many of the other drawbacks to an EOR approach. Spacecraft are only certified for a limited amount of time in space and delays to the fuel tankers could be an issue. SpaceX's starship is built to handle a Mars mission lasting a few years anyway, so delays in LEO are proportionately less of an issue.

Pretty much this, once they found they could use an dedicated lander from moon orbit, down and up again this will win. Refueling using extra N-1 would just increase cost and risk of fail if refueling failed. 

Starship if working out changes this by making orbital launches cheap compared to an dedicated moon lander so you can do say 20 tanker flight to pull this off it still probably works, yes they might also has to call it because problems. but then they just do an moon flyby to dump fuel and try later. 

Still if you do regular trips to an base on moon you would want an dedicated lander anyway simply to save fuel even if having to bring it from earth. 

[DDE]

5 hours ago, VictoryNeverFail said:

Ok guys, I know direct accent is possible in reality, I know what the saturn 8 nova is, what I'm asking is it possible to properly fund such an enormous and powerful rocket.

A lot depends on how cheap you can make the UR-700 with its nine stacks, non-cryogenic propellants, but very elaborate engines. Versions with crews of three actually required ten nuclear rockets in two stages.

Something that hasn’t been mentioned is the eight-booster vertical-stack Energiya creeping into the DA IMLEO range.

The problem with all superheavies - including, to a lesser degree, Starship - is the scarcity of payloads and missions strictly requiring a superheavy. Which is why you end up in SLS territory.

[tater]

52 minutes ago, DDE said:

The problem with all superheavies - including, to a lesser degree, Starship - is the scarcity of payloads and missions strictly requiring a superheavy. Which is why you end up in SLS territory.

This is certainly true for any expendable launch vehicle. If the vehicle can be reused, the vehicle cost is the cost divided by the number of flights it can make. Propellants are a small % of cost (a million or two). For any reusable (rapidly/cheaply) vehicle, the possible mass to orbit doesn't matter, it's price/kg as flown (ie; not XX M$/100+ tonnes, but XXM$/actual_payload_mass_this_flight) that decides the economics.

 

[kerbiloid]

5 hours ago, DDE said:

The problem with all superheavies - including, to a lesser degree, Starship - is the scarcity of payloads and missions strictly requiring a superheavy.

And that was the point of the original UR-700 (leaving alone the question of its dynamical stability, lol).
It should be made of serially manufactured components of Proton family, 4 m in diameter.
So, when you don't need UR-700, the same plant would just keep producing Proton. A lego rocket.

Also, the same 4 m wide equipment of KSC, railroad, etc. Just use it for a Proton or for a UR-700 module.
And already being built launchpads of N-1.

Also, unlike the cryorockets, it could stay fueled on the launchpad for months.

Edited May 30, 2019 by kerbiloid

[DerekL1963]

On 5/29/2019 at 5:59 AM, tater said:

Of course they will be refilling the spacecraft in orbit first.

If it stops in orbit, it's not Direct Ascent...

[Bill Phil]

11 hours ago, kerbiloid said:

And that was the point of the original UR-700 (leaving alone the question of its dynamical stability, lol).
It should be made of serially manufactured components of Proton family, 4 m in diameter.
So, when you don't need UR-700, the same plant would just keep producing Proton. A lego rocket.

Also, the same 4 m wide equipment of KSC, railroad, etc. Just use it for a Proton or for a UR-700 module.
And already being built launchpads of N-1.

Also, unlike the cryorockets, it could stay fueled on the launchpad for months.

Yeah, but imagine the damage if the thing exploded? That stuff is toxic... thousands of tonnes of it probably isn't a recipe for success - let alone flying people on it.