Better than asparagus staging?

[Javster]

Mostly depends on what you call "better".

Think about it this way:

•Is your system cheap?

•Are you using durable techniques? (As in something that may be still useful after an aerodynamics update for example)

•Are the parts you are using considered OP? (NERVAs, Turbojets)

•Are the parts you are using going to remain the same during updates?

•Are you using techniques considered cheaty? (Air-hogging, intake stacking)

•Does your lifter look good?

•What's the maximum payload to LKO?

•Can you make a cheaper system with the same payload capacity?

•Can you make a system with the same capacity but with less parts?

Edit: I forgot some important ones.

•Are you using mods?

•Are you using mods that are considered "OP" or "unrealistic" or "unbalanced" ?

That's what defines a good lifter for me.

*fewer parts

Those are great parameters though.

[Tuupertunut]

I have made some tests with jets as lifters too. For the fuel, I suggest to use engine clusters with one fuel tank in the middle and a few (maybe 4-8) engines and their intakes on girder segments or m-beam 650s. (I'd use the m-beam for lower mass) This way you'll save a lot of mass. Also do the gravity turn in 10km and of course, use turbojets because you can get higher with those.

Picture:

[Galane]

Check the 0.22 changelog, nose cones do improve stability in atmo now.

But they still do not reduce drag VS the flat nose of a bare fuel tank. Stick a cone on a tank and you have the combined drag of both. To make them work properly would require them to be able to have a minus effect on the drag of the non-nosecone component they're attached to, but not so much as to throw things into negative drag numbers.

There would also need to be a way to block cone stacking to get crazy low drag numbers and again to prevent negative numbers. Imagine stacking 100 nose cones with a simple minus to drag and having the rocket just spring into the air from all that negative drag sucking it up to 10KM.

As they are, still better to forget the nose cones and save the useless weight and increased drag.

[Dispatcher]

As for nose cones, what if they had fuel in them (and reduced drag)? See my sig line.

For the topic, I'd add that its good to try using a mix of engines that you've not tried before. The combination of types and quantities can yield interesting results which would be hard discern by just looking at their specs.

[EatVacuum]

jets are for planes.

it seems every couple of updates, people find this new "cheaty" way to get stuff into space.

I'm so old fashioned.

How can you say "cheaty" given all the research and testing on ram rockets (air breathing rockets, including boosters), dual cycle engines (I.e. jet/rocket hybrids that has gone on in the real world since the fifties to now? It's not cheating if it is simulating something that is posssible in reality. Using jets is no more cheaty than using the nuclear rocket stock part. In fact there is a lot more research in alternatives to old style rockets now with the commercialization of space than ever happened under NASA or the Soviet programs. This year the U.K. government threw 60 million pounds over to Reaction Engines for development of the Sabre engine (which is a hybrid jet to rocket design) and the ESA is interested as well. Also look at the older American GTX and Soviet Gnom air breathing rockets. So really, why complain about jets?

Edited October 29, 2013 by EatVacuum
Somehow part of another posting got in here

[numerobis]

The KSP jets are incredibly light, powerful, and efficient and they go very fast. IRL, a turbofan can't go mach 2.5; a turbojet can't go mach 6.

[Kasuha]

Using jets to get rockets to space is not cheating. It's just feeling unnatural because it's not used in real world. But we're playing a game here, right? Asparagus staging is not widely used, too, and real world rockets are thin and tall to avoid atmospheric drag, something you usually don't care too much about in KSP. Everybody just sets up their own level of realism for playing this game.

[phunk]

Using jets to get rockets to space is not cheating. It's just feeling unnatural because it's not used in real world

It's not completely unheard of...

http://en.wikipedia.org/wiki/File:Spaceship_One_and_White_Knight_in_flight_1.jpg

[700NitroXpress]

Using jets to get rockets to space is not cheating. It's just feeling unnatural because it's not used in real world. But we're playing a game here, right? Asparagus staging is not widely used, too, and real world rockets are thin and tall to avoid atmospheric drag, something you usually don't care too much about in KSP. Everybody just sets up their own level of realism for playing this game.

Perfect explanation, thank you.

[PDCWolf]

How can you say "cheaty" given all the -snip-

Cheaty because they are considered OP. They are even better than real life counterparts.

Using jets to get rockets to space is not cheating. It's just feeling unnatural because it's not used in real world. But we're playing a game here, right? Asparagus staging is not widely used, too, and real world rockets are thin and tall to avoid atmospheric drag, something you usually don't care too much about in KSP. Everybody just sets up their own level of realism for playing this game.

I bet the guy was talking about general consensus or even his own opinion. Wether you care or not if other people call you a cheater is your own thing. There are facts that you can't deny.

On a downscaled world (where all other parts have been also downscaled from real-life values) the turbojets perform way better than their real-life counterparts. That is a fact.

As a side remark, you can also spam intakes to make them work at stupid altitudes, which won't happen in real life.

They are OP, and people call them cheaty because of that. Whether you care about it or not is your own concern.

[JoCRaM]

Check the 0.22 changelog, nose cones do improve stability in atmo now.

yes, but he's using tails instead of cones (and tails don't improve stability yet, and if they did they would make stability worse if you stuck them on the front of a ship.

[Hovis]

OP is not cheaty. If it's in the game, it's in the game.

I think it's a very clever idea and something I might well pinch for my own plans. My lifters are usually bodged together with all sorts of rockets, boosters and voodoo. Anything that can get a heavy payload into atmo has my attention.

[PDCWolf]

OP is not cheaty. If it's in the game, it's in the game.

I'll call the very well known technique used around here.

ITS AN ALPHAAAAA whilst dancing flailing my arms and making retarded noises.

[700NitroXpress]

I didn't post this to argue the real world physics or counter parts. I posted this to get opinions of the usefulness of the system compared to other methods that are used in this game. There are other threads to discuss physics and what should or shouldn't be possible. If you find this method useful and easy, great. If you prefer to use asparagus, that's fine too. I find this to be useful for lifting heavy payloads into orbit with a lot less rockets and setup. I can deploy this system a lot easier than rigging up sets of rockets and boosters.

There is more here than just the air lift. Here are the other parts of the system that I haven't seen anyone address yet:

1. Air lift

2. Orbital burn rocket

3. Engine refit system

The orbital burn rocket could be made even lighter if I chose to asparagus it instead of not. The engine refit with the docking ports is my key element of this system next to the air lift. I can attach a full fuel engine of any size and configuration in orbit without having to launch the whole thing from the ground. This allows me to fit the ship with the right amount of fuel and engines for it's mission without having to reconstruct everything.

Thoughts on that?

[TheCanadianVendingMachine]

Personally, I don't see why you have to lift a lot to orbit anyhow. I find 23 tons to be pretty good. I have a rocket that can lift (almost)any payload up to the Mun in it's first stage alone. Sure, Jet's are more efficient, but what about part count? A basic 23 part rocket can get heavy payloads into orbit, even space stations.

[A1catraz]

Mostly depends on what you call "better".

Think about it this way:

•Is your system cheap?

•Are you using durable techniques? (As in something that may be still useful after an aerodynamics update for example)

•Are the parts you are using considered OP? (NERVAs, Turbojets)

•Are the parts you are using going to remain the same during updates?

•Are you using techniques considered cheaty? (Air-hogging, intake stacking)

•Does your lifter look good?

•What's the maximum payload to LKO?

•Can you make a cheaper system with the same payload capacity?

•Can you make a system with the same capacity but with less parts?

Edit: I forgot some important ones.

•Are you using mods?

•Are you using mods that are considered "OP" or "unrealistic" or "unbalanced" ?

That's what defines a good lifter for me.

I agree, asparagus staging is a lot simpler and is more efficient. Yours is complicated and requires more part than asparagus. How did you even come up with that?

[700NitroXpress]

I agree, asparagus staging is a lot simpler and is more efficient. Yours is complicated and requires more part than asparagus. How did you even come up with that?

I think my way is a lot simpler because there is not need for fuel lines to be rigged up, one stage for the couplers, it's more compact, if you use fuel from one tank only then it's only three parts per engine, uses less fuel, has less weight, can be used more effectively with larger craft.

I came up with it because I needed to get my Duna Command Center into orbit in all one piece and that's a heavy payload. I figured, why not use air powered engines to get up through the atmosphere and then save the rockets for the orbital burn. It worked on the first try so I started using it for other craft and so far it hasn't failed to lift anything into orbit.

This is the largest object I've lifted into orbit with this method. Big H.O.S.S. (Helios Orbital Solar Station) 1015 Parts 248.96 tons

This is the heaviest object I've lifted into orbit with this method. Kerban Fuel Depot. 398 Parts 923.56 tons.

Edited October 29, 2013 by 700NitroXpress

[Armchair Rocket Scientist]

Not sure if anyone has mentioned this yet, but Scott Manley's launcher for Reusable Space Program was very similar:

[KvickFlygarn87]

I think my way is a lot simpler because there is not need for fuel lines to be rigged up, one stage for the couplers, it's more compact, if you use fuel from one tank only then it's only three parts per engine, uses less fuel, has less weight, can be used more effectively with larger craft.

I came up with it because I needed to get my Duna Command Center into orbit in all one piece and that's a heavy payload. I figured, why not use air powered engines to get up through the atmosphere and then save the rockets for the orbital burn. It worked on the first try so I started using it for other craft and so far it hasn't failed to lift anything into orbit.

This is the largest object I've lifted into orbit with this method. Big H.O.S.S. (Helios Orbital Solar Station) 1015 Parts 248.96 tons

-snip-

This is the heaviest object I've lifted into orbit with this method. Kerban Fuel Depot. 398 Parts 923.56 tons.

-snip-

Holy moly that's a big station. Mind posting pics of the launcher and/or download link? I need that kind of thing for -ahem- crashing things.

[DrMonte]

I've tried JetLifter as first stage up to the ~25km (add more air intake). Had about 50 Jet engines plus 2-3 x 100t fuel tanks (depending on load).

From simple gamer perspective I just don't see this as stable enough lifter. It is hard to control, at all - it requires additional attention during launch. And it is limited when we talk about bigger rockets (as good your PC are you are still limited on parts count when it comes to thousands).

As for realism - it would be practical to use jet lifters if you would reuse them.

[700NitroXpress]

Holy moly that's a big station. Mind posting pics of the launcher and/or download link? I need that kind of thing for -ahem- crashing things.

Yeah, but I hope your computer can handle it, looking at 1500 + parts.

I'll make a thread for it in the space craft exchange called Big H.O.S.S. I'll also make a youtube showcase video for it and have that as well as the download link. Probably won't be up there until 11/2/13

Edited October 30, 2013 by 700NitroXpress

[boomerdog2000]

Eh call me a traditionalist but I'm going to keep my jet engines for planes. I'm not against others doing it, it just feels weird to me.

[Avanti]

the SR-71 black bird used turbojets, but at higher altitude, the engine converted to a ram-jet engine, hence the ridiculous air intake design, turbo's on their own have trouble above mach 2

[700NitroXpress]

the SR-71 black bird used turbojets, but at higher altitude, the engine converted to a ram-jet engine, hence the ridiculous air intake design, turbo's on their own have trouble above mach 2

If you're referring to turbo jets in KSP, I've gotten an SSTO plane up to Mach 5 on just the turbo jets alone for sustained flight.

SSTO going at 1716.0 m/s

[gm537]

It makes sense. Rocket engines were scaled to fit the atmospheric model and have low ISPs because of that, to be balanced with the game. They are underpowered in terms of real life. Turbojets and the normal jet engine were not scaled and are incredibly overpowered, even for their real life counterparts.

KSP rockets have lower ISP than their real world counter parts?!? Where the crap do you get that idea? Based on the densities and mixture ratios of the generic "Liquid Fuel and Oxidizer" in game it's pretty safe to say we are talking about RP-1 and LOX on real rockets these have ISP's of around 270 in atmosphere and 310 in vacuum. In game though: 320 in atmosphere and 370 in vacuum (for the LV-T30 and T45) a nearly 20% bonus.

http://history.nasa.gov/conghand/propelnt.htm

http://www.braeunig.us/space/propel.htm

On the subject of air breathing engines, is it so unreasonable to assume that the KSP "turbojet" is actually a "ramjet" which according to Wiki "work most efficiently at supersonic speeds around Mach 3. This type of engine can operate up to speeds of Mach 6." Oh wait KSP turbojet max power at 1000m/s approx Mach 2.94 and stops working at 2400m/s approx Mach 7. Stop whining it's not over powered it's just mislabeled and simplified for the sake of a game. Check facts before spewing incorrect information in an attempt to justify your unreasonable position.