Commercial Cargo, Commercial Crew, but not Commercial Propellant?

[sdsds]

It seems odd the Senate is proposing continued funding for the development and use of commercial cargo, adding funding for the development of commercial crew, but not in any way even mentioning commercial propellant.

Isn't commercial launch of propellant to a government depot something that should be encouraged?

[nooneofconsequence]

It seems odd the Senate is proposing continued funding for the development and use of commercial cargo, adding funding for the development of commercial crew, but not in any way even mentioning commercial propellant.

Isn't commercial launch of propellant to a government depot something that should be encouraged?

Competes with HLV in many eyes, so undercuts politically. Not yet a viable option unfortunately.

[A_M_Swallow]

It seems odd the Senate is proposing continued funding for the development and use of commercial cargo, adding funding for the development of commercial crew, but not in any way even mentioning commercial propellant.

Isn't commercial launch of propellant to a government depot something that should be encouraged?

Depot equipment testing is covered by the Exploration Flagship Technology Demonstrations.  It depends on whether or not they get sufficient money.  Followed by who gets to operate the depot.

[Sparky]

It seems odd the Senate is proposing continued funding for the development and use of commercial cargo, adding funding for the development of commercial crew, but not in any way even mentioning commercial propellant.

Isn't commercial launch of propellant to a government depot something that should be encouraged?

I assumed that propellant would fall under the category of cargo. The only difference is that the cargo is liquid and needs to get to L1/L2 rather than LEO. A Falcon9 heavy could get a goodly amount of propellant to a depot, even though dragon is a bit small for the task, SpaceX might be able to derive a purpose built tanker from it.

[Robotbeat]

Of course, the Senate compromise removes most of the money away from exploration/space tech, so the depot wouldn't get a lot of funding. Thank goodness our Congresscritters are doing their jobs, keeping us planted firmly in the 20th Century! Rockets, not payloads!

[yg1968]

Of course, the Senate compromise removes most of the money away from exploration/space tech, so the depot wouldn't get a lot of funding. Thank goodness our Congresscritters are doing their jobs, keeping us planted firmly in the 20th Century! Rockets, not payloads!

Does it need a lot of funding? I thought the propellant depot technology was essentially ready.

[Proponent]

Does it need a lot of funding? I thought the propellant depot technology was essentially ready.

It needs to be demonstrated.  That's a small project compared to building and HLV, but it's not entirely trivial.

[Jim]

I assumed that propellant would fall under the category of cargo. The only difference is that the cargo is liquid and needs to get to L1/L2 rather than LEO. A Falcon9 heavy could get a goodly amount of propellant to a depot, even though dragon is a bit small for the task, SpaceX might be able to derive a purpose built tanker from it.

Why single out Spacex?  EELV could carry more

[e of pi]

I assumed that propellant would fall under the category of cargo. The only difference is that the cargo is liquid and needs to get to L1/L2 rather than LEO. A Falcon9 heavy could get a goodly amount of propellant to a depot, even though dragon is a bit small for the task, SpaceX might be able to derive a purpose built tanker from it.

Why single out Spacex?  EELV could carry more

With a depot architecture, wouldn't fuel transfer be more about cost per kg than amount per one launch? If SpaceX can get the same fuel up for half the cost, then why is taking more launches a bad thing? Being able to use a depot stops that from being an issue, right? (I'm not saying SpaceX could do it for half the cost, I have no idea about the real numbers.)

[Patchouli]

It seems odd the Senate is proposing continued funding for the development and use of commercial cargo, adding funding for the development of commercial crew, but not in any way even mentioning commercial propellant.

Isn't commercial launch of propellant to a government depot something that should be encouraged?

I assumed that propellant would fall under the category of cargo. The only difference is that the cargo is liquid and needs to get to L1/L2 rather than LEO. A Falcon9 heavy could get a goodly amount of propellant to a depot, even though dragon is a bit small for the task, SpaceX might be able to derive a purpose built tanker from it.

I think it would be better to derive the tanker from the F9 US and Centaur stages off the EELV.

Also allow use of any LV to bring the payload be it F9, an EELV, Ariane or even some future RLV.
Have them in three standard sizes 10T, 20T and 30T.

Once the tanker is in orbit have something like the SS/L 1300 tug fetch the payload and take it to the depot.
http://www.constellationservices.com/SSL_COTS_Fact_Sheet_Dec_2007.pdf

The tanker should be just that a simple tank with a very basic attitude control system and means for deorbit.

This makes the tanker cheap as all the expensive avionics remain in the tug which could perform dozens of missions before needing replacement.

[Jim]

I think it would be better to derive the tanker from the F9 US and Centaur stages off the EELV.

The Delta IV upperstages would be better with separate tanks.  The F9 US would be the worse

[kkattula]

Would a contract to deliver propellant to a depot, be enough incentive for ULA to develop ACES?

[MP99]

...or SpaceX to develop Raptor?

cheers, Martin

[kevin-rf]

Would a contract to deliver propellant to a depot, be enough incentive for ULA to develop ACES?

With the common bulkhead would you have long term thermal issues with the LOX getting to cold?

[kkattula]

IIRC, the greater heat capacity of the LH2 keeps the LOX cold. Trading a small mass of H2 boil-off for zero LOX boil-off.