How would YOU evolve the Antares?

[thydusk666]

Thank you all for your comments.

I agree that new strategies have to be drawn out considering SpaceX is expected to cast its shadow over many competitors. But this is not a bad thing, as it can only lead to strong competition, which in turn, produces great things like innovation, invention and (hopefully) lower prices.

On a side note, I think OSC has done a great job by integrating existing systems from different suppliers around the Globe, into a fully functional rocket!
If I'm not mistaken, this has never quite happened before, at least at this scale.

I am really curious how this strategy will play out on a longer term and if it will allow competitive $/kg.

Go Orbital!

[Jim]

I think the real key to determining which is cheaper isn't total price, but price per kg to orbit.

No, it is total price.  That's how they are marketed and bought.  A customer has a spacecraft, he is going to look at what the cheapest cost to put that spacecraft into orbit.  Excess LV is of no use to him on less it can be translated into spacecraft propellant being saved.  But for a LEO mission, that is unlikely.

[thydusk666]

I think the real key to determining which is cheaper isn't total price, but price per kg to orbit.

No, it is total price.  That's how they are marketed and bought.  A customer has a spacecraft, he is going to look at what the cheapest cost to put that spacecraft into orbit.  Excess LV is of no use to him on less it can be translated into spacecraft propellant being saved.  But for a LEO mission, that is unlikely.

Deppends on the marketing strategy, no?
I think once you publish a price/kg to LEO, commercial customers can have a better insight on what you're offering. Especially if you want to fill in the excess capacity with secondary payloads (cubesats for instance). Transparency is good PR, if you have competitive prices.

[Lurker Steve]

If you are looking to compare SpaceX and Orbital, read the following paragraph from their latest quarterly report :

For the remainder of the year, Orbital plans to conduct numerous major operational events, highlighted by two additional Antares launches and Cygnus spacecraft deployments to the International Space Station, the introduction of the Minotaur V rocket that will launch NASA's LADEE spacecraft into lunar orbit from Wallops Island, a Pegasus rocket launch carrying a NASA heliophysics satellite, a Minotaur I rocket launch of an Air Force satellite, the deployment of two or three commercial communications satellites, and one or two additional flights of the company's OBV interceptor booster.  In addition, the company expects to carry out several target vehicle launches as well as up to 15 additional suborbital research rocket missions.  Orbital will also deliver several additional systems for future missions or operational deployments

So, it appears Orbital will be MUCH busier on the launch pad than SpaceX. They just have multiple LVs that are sized (and priced) according to the customer need instead of one size fits all.

[Downix]

If you are looking to compare SpaceX and Orbital, read the following paragraph from their latest quarterly report :

For the remainder of the year, Orbital plans to conduct numerous major operational events, highlighted by two additional Antares launches and Cygnus spacecraft deployments to the International Space Station, the introduction of the Minotaur V rocket that will launch NASA's LADEE spacecraft into lunar orbit from Wallops Island, a Pegasus rocket launch carrying a NASA heliophysics satellite, a Minotaur I rocket launch of an Air Force satellite, the deployment of two or three commercial communications satellites, and one or two additional flights of the company's OBV interceptor booster.  In addition, the company expects to carry out several target vehicle launches as well as up to 15 additional suborbital research rocket missions.  Orbital will also deliver several additional systems for future missions or operational deployments

So, it appears Orbital will be MUCH busier on the launch pad than SpaceX. They just have multiple LVs that are sized (and priced) according to the customer need instead of one size fits all.

And the various launch vehicles use components which share tooling and expertise with each other, improving their overall cost without going for the "one size fits all" approach.

It makes Orbital far more flexible, while keeping their costs in-line.

[Hyperion5]

I think the real key to determining which is cheaper isn't total price, but price per kg to orbit.

No, it is total price.  That's how they are marketed and bought.  A customer has a spacecraft, he is going to look at what the cheapest cost to put that spacecraft into orbit.  Excess LV is of no use to him on less it can be translated into spacecraft propellant being saved.  But for a LEO mission, that is unlikely.

I can't quite agree with that statement, Jim, because it does not explain why the cheap Zenit is now regularly launched less than the much more expensive and larger Ariane 5.  I think this statement should be amended to: "A customer is going to look for the cheapest reliable way of putting a spacecraft into orbit".  Also, a low price per kg is crucial for firms like Spacex to make an otherwise over-sized LV attractive because it's reflected in a lower launch cost.  If a larger rocket has a similar launch price to a smaller rocket, I don't think most satellite firms would care about excess capacity.  They might however if it meant more margin for overcoming problems during launch (say losing an engine) if that increases reliability.   

[Jim]

They might however if it meant more margin for overcoming problems during launch (say losing an engine) if that increases reliability.   

False "reliability".  First stage  is less than 2/3 of the total flight time and the remaining time is with a single engine.

[spectre9]

RL-10 upper stage would be cool.

Expensive but might be worth it to really max out the performance.

[Zed_Noir]

RL-10 upper stage would be cool.

Then you need to install new LH GSE on the pad.

What the Antares need is a relatively cheap restartable KeroLox or hypergolic upper stage. Something like the AJ-10 on the Delta II.

My fantasy choice is for Orbital to buy some SuperDraco engines for a new upper stage. Of course only if SpaceX is willing to sell.

[Lobo]

RL-10 upper stage would be cool.

Then you need to install new LH GSE on the pad.

What the Antares need is a relatively cheap restartable KeroLox or hypergolic upper stage. Something like the AJ-10 on the Delta II.

My fantasy choice is for Orbital to buy some SuperDraco engines for a new upper stage. Of course only if SpaceX is willing to sell.

I think since they already have a kerolox 1st stage, kerolox at the pad, and a kerolox engine that's capable of being used as either a booster or upper stage engine, I'd think some sort of modified NK-33 to make it an NK-43, and maybe detune it for lower thrust (as the NK-43 would probably have much too much thrust to be used as an upper stage for Antares class payloads) would be the logic choice. 
That might add cost though over the Castor upper stage.  So if they are really just shooting for a lot cost Delta II equivalent, there might not be much reason for that.  Maybe as an option to compete for EELV class loads if they want?

 

[MATTBLAK]

The further use of Russian rocket engines is logical as there certainly is a family of available ones. A hypergolic upper engine is also a logical step - I can imagine an LR-91 from Titan might make a good choice as its thrust and efficiency is a bit better than the Castor BA or XLs that are Antares current upper stage. Such an upper stage stage along with the 550k thrust AJ26-500 engine first stage upgrade would turn Antares into a pretty formidable booster. And while we're playing rocket Lego, buying some solids from Aerojet as well as the LR-91 and mounting a pair or even a quartet of them would put the Antares into medium-heavy territory.

[Zed_Noir]

The further use of Russian rocket engines is logical as there certainly is a family of available ones. A hypergolic upper engine is also a logical step - I can imagine an LR-91 from Titan might make a good choice as its thrust and efficiency is a bit better than the Castor XL that is Antares current upper stage. Such an upper stage stage along with the 550k thrust AJ26-500 engine first stage upgrade would turn Antares into a pretty formidable booster. And while we're playing rocket Lego,  buying some solids from Aerojet as well as the LR-91 and mounting a pair or even a quartet of them would put the Antares into medium-heavy territory.

Recall someone (maybe Jorge) mention on another thread that Eastern Bloc booster cores are not compatible with SRM.

Besides the out of production status of the LR91. Which would need new facilities for re-development & production. It uses Aerozine 50 as fuel and is a gas generator hypergolic engine. Might not be cheap to find a turbo-pump supply source.

[Zed_Noir]

RL-10 upper stage would be cool.

Then you need to install new LH GSE on the pad.

What the Antares need is a relatively cheap restartable KeroLox or hypergolic upper stage. Something like the AJ-10 on the Delta II.

My fantasy choice is for Orbital to buy some SuperDraco engines for a new upper stage. Of course only if SpaceX is willing to sell.

I think since they already have a kerolox 1st stage, kerolox at the pad, and a kerolox engine that's capable of being used as either a booster or upper stage engine, I'd think some sort of modified NK-33 to make it an NK-43, and maybe detune it for lower thrust (as the NK-43 would probably have much too much thrust to be used as an upper stage for Antares class payloads) would be the logic choice. 
That might add cost though over the Castor upper stage.  So if they are really just shooting for a lot cost Delta II equivalent, there might not be much reason for that.  Maybe as an option to compete for EELV class loads if they want?

the idea was a cheap restartable liquid engine for a new  Antares upper stage,

A pump feed hypergolic engine should be a lot cheaper than a staged comubustion kerolox engine.

[MATTBLAK]

Yeah - kind of the reason I bought up the LR-91. Its not so many years out of production that bringing it back would be unfeasible. And I don't imagine it would be impossible to address the Aerozine 50 problem and changing to UDMH. But if that's in the too-hard basket, another engine that springs to mind is the old Ariane Viking engine that in its most recent form made 750kn or 17,000 pounds thrust. But that wouldn't be enough thrust and neither would the Delta II's AJ-110 series, even in a cluster of 4.

So I think a decent in-production candidate would be the Proton's RD-0212 engine with more than 320 seconds specific impulse and 640kn of thrust - about 138,000 pounds: http://www.astronautix.com/engines/rd0212.htm

[Lobo]

RL-10 upper stage would be cool.

Then you need to install new LH GSE on the pad.

What the Antares need is a relatively cheap restartable KeroLox or hypergolic upper stage. Something like the AJ-10 on the Delta II.

My fantasy choice is for Orbital to buy some SuperDraco engines for a new upper stage. Of course only if SpaceX is willing to sell.

I think since they already have a kerolox 1st stage, kerolox at the pad, and a kerolox engine that's capable of being used as either a booster or upper stage engine, I'd think some sort of modified NK-33 to make it an NK-43, and maybe detune it for lower thrust (as the NK-43 would probably have much too much thrust to be used as an upper stage for Antares class payloads) would be the logic choice. 
That might add cost though over the Castor upper stage.  So if they are really just shooting for a lot cost Delta II equivalent, there might not be much reason for that.  Maybe as an option to compete for EELV class loads if they want?

the idea was a cheap restartable liquid engine for a new  Antares upper stage,

A pump feed hypergolic engine should be a lot cheaper than a staged comubustion kerolox engine.

There is more than just the cost of the engine.  The cost of upgrading their pad and infrastructure to handle that too.  A kerolox stage could pretty much use all their existing assets.
I believe Aerojet bought the NK33's for like 1 million each?  Not sure how much they are charging OSC for them, but would an adequate hyperbolic engine be significantly cheaper that 1 million bucks or so?

[MATTBLAK]

Single NK33 it should be then! Does it need a nozzle extension for upper stage duties? Does it need to be throttled down for this use?

[Hyperion5]

Single NK33 it should be then! Does it need a nozzle extension for upper stage duties? Does it need to be throttled down for this use?

You would absolutely need to throttle down an NK-33, but even then, I believe they only throttle down to around ~55% of their maximum.  An RD-191 will throttle all the way down to 30% of maximum, but that's got way too much power for US work on the Antares, as does the NK-33.  In general, I stick to using the Saturn V as a guideline. 

The Saturn V design would suggest if we're trying to max this thing out while minimizing design issues, something with 1/7th-1/9th the thrust of the booster engines at sea level is a good choice.  Now I know people are objecting to putting a hydrogen supply at the pad and dealing with its issues, but it'd let you use the best-proportioned engine I can think of for this rocket, a Blue Origin BE-3 hydrolox engine.  The Antares is taking off with around 740,000 lbs of thrust at liftoff (due to pushing its engines over 100% rating).  A BE-3's 100,000 lbs of thrust would be ideally proportioned and deliver a big boost to the Antares' capabilities.  My only concern is I don't know if Blue Origin would sell such a great engine to a possible competitor. 

If there's a setup that would be engineering-feasible but not politically feasible, I'd say it's using a quartet of RD-0146 engines.  You should be able to fit them into a 3.9 m core and get a big boost in performance from their 463 seconds of Isp.  Their biggest fault is they're not restartable to my knowledge, and that to me makes them little better than what the Antares has now.  I think a restart capability on the 2nd stage is a must for any possible US upgrade.  If the Antares' engines are upgraded to AJ-500 engines, that'd open up a new range of possible US engines.  You might even be able to chance using the Zenit's RD-120 2nd stage engine.  I'd still detune and modify that engine to make it more ideal however. 

[hop]

Ariane Viking engine that in its most recent form made 750kn or 17,000 pounds thrust. But that wouldn't be enough thrust

I think you dropped a decimal there. 750kn is ~ 170,00 lbf (~76 tons) which is a bit much for an Antares upper stage. Remember they wanted to use the RD-0124, which is ~30 tons.

Even if it weren't too much engine, I very much doubt Orbital or any other western manufacturer wants to deal with hypergols in the quantities that would be needed for a second stage. But if they did, India still produces Viking derivatives for PSLV and GSLV...

Single NK33 it should be then! Does it need a nozzle extension for upper stage duties? Does it need to be throttled down for this use?

NK-33 with an extended nozzle exists, it's called an NK-43, but at 1700kn it's way too much engine.

[R7]

Single NK33 it should be then! Does it need a nozzle extension for upper stage duties?

Not necessarily. NK-33 vacuum Isp 331s (Astronautix.com) is better than both LR-91/RD-0212. NK-43 is 345s.

Has there been information floating around about how many NK-43s Aerojet bought, or were they all NK-33s? And is the 43 nozzle extension a "simple" bolt-on to 33, or entirely different regen nozzle?

Does it need to be throttled down for this use?

Depends on the rocket design, how large acceleration your stage and payload can handle?

[MATTBLAK]

Ariane Viking engine that in its most recent form made 750kn or 17,000 pounds thrust. But that wouldn't be enough thrust

I think you dropped a decimal there. 750kn is ~ 170,00 lbf (~76 tons) which is a bit much for an Antares upper stage. Remember they wanted to use the RD-0124, which is ~30 tons.

Even if it weren't too much engine, I very much doubt Orbital or any other western manufacturer wants to deal with hypergols in the quantities that would be needed for a second stage. But if they did, India still produces Viking derivatives for PSLV and GSLV...

Single NK33 it should be then! Does it need a nozzle extension for upper stage duties? Does it need to be throttled down for this use?

NK-33 with an extended nozzle exists, it's called an NK-43, but at 1700kn it's way too much engine.

Spit! You're right!! Thanks: I misread that as 75.8 kilonewtons when I looked it up, not 758kN. So it actually has more thrust than the RD-0212. Fascinating...