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Commercial and US Government Launch Vehicles => Other US Launchers => Topic started by: Skyrocket on 02/09/2015 01:45 pm

Title: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Skyrocket on 02/09/2015 01:45 pm
Has anyone some more info on the SALVO vehicle?

This is, what i have found so far (http://space.skyrocket.de/doc_lau/salvo.htm):

The SALVO (Small Air Launch Vehicle to Orbit) is a small launch vehicle developped by Ventions. Inc. for DARPA as a pathfinder for the ALASA launch vehicle.

The vehicle will be air launched by a F-15E fighter after take off from Eglin, Florida. SALVO uses LOX and RP1 as propellants and battery-powered pumps for its rocket engines.

It will be able to put a 5kg 3U Cubesat into orbit.

The test vehicle was shipped in October 2014 to Eglin. First launch is planned for spring 2015.

http://spacenews.com/40769darpa-developing-operational-pathfinder-for-alasa-air-launch-system/

http://ventions.com/2014-news
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: catdlr on 02/09/2015 06:53 pm
addition ALASA information here:

http://forum.nasaspaceflight.com/index.php?topic=34350.0
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: jongoff on 02/09/2015 09:25 pm
Has anyone some more info on the SALVO vehicle?

This is, what i have found so far (http://space.skyrocket.de/doc_lau/salvo.htm):

The SALVO (Small Air Launch Vehicle to Orbit) is a small launch vehicle developped by Ventions. Inc. for DARPA as a pathfinder for the ALASA launch vehicle.

The vehicle will be air launched by a F-15E fighter after take off from Eglin, Florida. SALVO uses LOX and RP1 as propellants and battery-powered pumps for its rocket engines.

It will be able to put a 5kg 3U Cubesat into orbit.

The test vehicle was shipped in October 2014 to Eglin. First launch is planned for spring 2015.

http://spacenews.com/40769darpa-developing-operational-pathfinder-for-alasa-air-launch-system/

http://ventions.com/2014-news

Two ex-Masten, ex-Altius guys are working at Ventions, but I haven't pumped them much for info on SALVO. And I probably couldn't share it even if I had. It's a neat vehicle though, and I've always been a fan of their electropump work.

~Jon
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Skyrocket on 04/16/2015 10:39 am
Ventions has published a small status update:

Quote
April:
Ventions begins cold-flow fill / drain and pressurization tests of SALVO 1st stage.

http://ventions.com/menu-1-1-2/
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Kryten on 06/12/2015 12:27 am
Quote
June:
Ventions completes acceptance testing of SALVO 1st stage engines.
http://ventions.com/menu-1-1-2/
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Skyrocket on 06/17/2015 06:47 am
I have just found this article on SALVO with an artist impression:

http://www.americaspace.com/?p=83211
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: john smith 19 on 06/17/2015 08:41 am
I have just found this article on SALVO with an artist impression:

http://www.americaspace.com/?p=83211
This is quite astonishing.

This looks close to being the first new air launched ELV to fly since the Pegasus XL in 1994.

It looks close to being able to realize the military dream of "responsive space"

What is curious is to what extent this architecture (LOX/RP1, apparently 2 conventional stages) is a "pathfinder" for the ALSA (nitrous oxide and Ethyn in the same tank with nozzles between stages).
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Skyrocket on 06/17/2015 08:47 am
This is quite astonishing.
What is curious is to what extent this architecture (LOX/RP1, apparently 2 conventional stages) is a "pathfinder" for the ALSA (nitrous oxide and Ethyn in the same tank with nozzles between stages).

According to the DARPA project manager, the pathfinder role is for how to operate an air launch system effectively, not for the launcher technology itself.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: john smith 19 on 06/17/2015 09:30 am
This is quite astonishing.
What is curious is to what extent this architecture (LOX/RP1, apparently 2 conventional stages) is a "pathfinder" for the ALSA (nitrous oxide and Ethyn in the same tank with nozzles between stages).

According to the DARPA project manager, the pathfinder role is for how to operate an air launch system effectively, not for the launcher technology itself.
That makes more sense.

This would also seem to be the ideal point to start design of the sort of payloads the system is expected to carry.

Clearly a unit no bigger than 3 cubesats isn't going to have the capability of a multi tonne satellite. So how do you split the capability of such a satellite into smaller units? Logically you fly more often but are there other strategies you can use to make those cubesats "punch above their weight"?
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: acsawdey on 06/17/2015 02:08 pm
The vehicle will be air launched by a F-15E fighter after take off from Eglin, Florida. SALVO uses LOX and RP1 as propellants and battery-powered pumps for its rocket engines.

Is there any additional information about the use of electric propellant pumps? After Rocketlabs announced they were going this route, I'm wondering if others were doing this first? It seems like it's a compelling alternative to solid or pressure-fed liquid for small rockets since turbopumps don't scale down all that well (mostly in terms of development expense).
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: john smith 19 on 06/18/2015 05:41 pm
Is there any additional information about the use of electric propellant pumps? After Rocketlabs announced they were going this route, I'm wondering if others were doing this first? It seems like it's a compelling alternative to solid or pressure-fed liquid for small rockets since turbopumps don't scale down all that well (mostly in terms of development expense).
True but there are other options.

At small sizes the compressed gas powered reciprocating pump from Flometrics (wonder what happened to them) confined the high pressure to a separate drive container tank.

There are also the XCOR and (Livermore) Whitehead teams for combustion driven versions.

AFAIK the notion of a separate pump drive process is viewed as very advanced, although looking back to Sangers work the system used a water cooling jacked around the chamber driving a steam turbine (which had about 40 yrs design history behind them by WWII).
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: kch on 06/18/2015 05:50 pm

At small sizes the compressed gas powered reciprocating pump from Flometrics (wonder what happened to them) confined the high pressure to a separate drive container tank.

Well, that was easy:

http://www.flometrics.com/ (http://www.flometrics.com/)

;)
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: acsawdey on 06/18/2015 06:48 pm
At small sizes the compressed gas powered reciprocating pump from Flometrics (wonder what happened to them) confined the high pressure to a separate drive container tank.

There are also the XCOR and (Livermore) Whitehead teams for combustion driven versions.

AFAIK the notion of a separate pump drive process is viewed as very advanced, although looking back to Sangers work the system used a water cooling jacked around the chamber driving a steam turbine (which had about 40 yrs design history behind them by WWII).

I had forgotten about the flowmetrics pump:  http://www.rocketfuelpump.com/

However a cursory search seems to show that the specific energy of compressed gas is significantly (5x?) lower than that of lithium ion batteries. I was only able to find an example for compressed air storage though, and perhaps helium would do better.

If you approximate a soda can sized brushless multiphase electric motor (as used for Rutherford engine) as solid Cu (9g/cc) and Nd (7g/cc) the weight must fall somewhere between 2.5 and 3.2 kg. From their illustrations the pump itself was considerably smaller and must therefore less than that. The flowmetrics system is just some tanks and valves so should also be pretty light.

The trade for the steam turbine vs a turbopump is an interesting one.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: edkyle99 on 06/18/2015 09:02 pm
I have just found this article on SALVO with an artist impression:

http://www.americaspace.com/?p=83211
There is a sentence in this story that gives me trouble.  It says that "[t]he future air launch of increasingly capable small spacecraft and Cubesats will be especially important as the USAF moves to smaller, more survivable satellites instead of more vulnerable multi-ton spacecraft". 

How is a microsatellite "more survivable" than a "multi-ton spacecraft"?  Isn't the microsatellite the inherently more "vulnerable" of the two?  A big spacecraft has, in theory, more available delta-v that it can use to maneuver away from a threat.  A microsatellite can only wait for its doom.  Also, these microsats are only LEO dwellers while the biggies are in GEO or other higher orbits.

 - Ed Kyle
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Space Ghost 1962 on 06/18/2015 09:57 pm
I have just found this article on SALVO with an artist impression:

http://www.americaspace.com/?p=83211
How is a microsatellite "more survivable" than a "multi-ton spacecraft"?
Smaller cross sectional area.

Quote
...Isn't the microsatellite the inherently more "vulnerable" of the two?
In having less "armor" yes. But with a kinetic kill, what's the use of any kind of protection?

Quote
A big spacecraft has, in theory, more available delta-v that it can use to maneuver away from a threat.
Conversely, a small sat has less mass so needs less props for same delta-v.

Quote
A microsatellite can only wait for its doom.
Propulsion systems for microsats are going to be more efficient/effective per pound/volume than big sats.

Targetting systems can't hide big sats. Swarms of small sats can be degraded but not eliminated.

Quote
  Also, these microsats are only LEO dwellers while the biggies are in GEO or other higher orbits.
Prepair yourself for interplanetary and hardened small sats. They are happening.

Now, to get to the reasonable confusion. Cubesats that are non-seriously done, "throw aways" confuse the issue and are quite commonplace.

But size itself matters not. If you competently make/test/qualify them, they can have the attributes (and costs) of the bigger sats.

There's another book I could write on all of this. Perhaps. Another part of this is the stealthy nature of small aggregates. Various nations are having fun with these at the moment.

Big sats aren't all going away either. If you need big optics, you'll have a big sat. But you might spread a platform over many smaller things.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: TrevorMonty on 06/18/2015 10:34 pm

At small sizes the compressed gas powered reciprocating pump from Flometrics (wonder what happened to them) confined the high pressure to a separate drive container tank.

Well, that was easy:

http://www.flometrics.com/ (http://www.flometrics.com/)

;)
Thanks for that link. Good idea.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: john smith 19 on 06/18/2015 11:11 pm
There's another book I could write on all of this. Perhaps. Another part of this is the stealthy nature of small aggregates. Various nations are having fun with these at the moment.

Big sats aren't all going away either. If you need big optics, you'll have a big sat. But you might spread a platform over many smaller things.

Yes I guess that's part of what SALVO is for. How the multi function, multi tonne satellite functions are split across several (many?) of these new nano sats.

An obvious move would be to replace large single, multi channel sats with a cluster of nanosats each with only 1 or 2 channels, trading altitude for power and number of channels per satellite. If a satellite fails then you've still got plenty of capacity.

This can be done with fairly straight forward architectures. I can see the problem becoming much more complex when you want coordinated behavior between a cluster, for example to apply some of the techniques of Synthetic Aperture RADAR to the optical bands.

I'm not sure the benefits are so clear cut. You'd be replacing a single large (and relatively passive) component with lots of comms and computation between the cluster. Now the cheapness of single string systems could work against you, as you need all of them working (or have on orbit spares) to deliver the same reliability as the large antenna or lens.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: a_langwich on 06/19/2015 02:20 am
I have just found this article on SALVO with an artist impression:

http://www.americaspace.com/?p=83211
There is a sentence in this story that gives me trouble.  It says that "[t]he future air launch of increasingly capable small spacecraft and Cubesats will be especially important as the USAF moves to smaller, more survivable satellites instead of more vulnerable multi-ton spacecraft". 

How is a microsatellite "more survivable" than a "multi-ton spacecraft"?  Isn't the microsatellite the inherently more "vulnerable" of the two?  A big spacecraft has, in theory, more available delta-v that it can use to maneuver away from a threat.  A microsatellite can only wait for its doom.  Also, these microsats are only LEO dwellers while the biggies are in GEO or other higher orbits.

 - Ed Kyle

My take on that is the author meant the constellation was more survivable, not the individual satellites.  Putting one smaller, cheaper sensor on a microsat, flying it in low LEO reduces distance for Maxwell's equations and for optics, but reduces the field of view and operating life, which is compensated by flying many units and refreshing continually.  Building many units with small cheap sensors reduces the unit cost, and the constant refreshment rolls out upgrades faster.  So now an opponent has a swarm of targets to attack, each of which is pretty cheap and easily replaced and not going to degrade the system capability much upon loss.  That deters attackers.

It's probably telling that SALVO is being launched from the same aircraft type that launched the US's only dedicated ASAT weapon.  You would want to be able to toss out new satellites with the same ease as deploying an ASAT, for your architecture to successfully withstand attack.

The key to making this work is keeping the individual sats simple and inexpensive. 

That works against the instincts of nearly every US military project manager, so we'll see how they do.  I suppose the time-honored military method is to find somebody who has the vision for how to make it work, put them in their own branch on the org chart to build a system, make them fight for funding against the big-sat guys, and see who wins the knife-fights.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: jongoff on 06/27/2015 12:09 am
I have just found this article on SALVO with an artist impression:

http://www.americaspace.com/?p=83211

I'm not sure what I can say publicly, but that article has a lot of errors, deprecated information, and outright silly speculation. I'd take almost everything in it with a particularly large grain of salt. Sorry I can't be more specific, I'm not sure which details are publicly mentionable, just wanted to warn people to take this article with the appropriate size grain (boulder?) of salt.

~Jon
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Bob Shaw on 06/27/2015 12:30 am
Surely SALVO is simply a modernised air-launched ASAT system? What else could it be, when the commercial world has looked at, and rejected, such micro-launchers time and time again, and for good reasons?

This is a weapons system, guys, and not in terms of information warfare, either.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Zed_Noir on 06/27/2015 01:41 am
Surely SALVO is simply a modernised air-launched ASAT system? What else could it be, when the commercial world has looked at, and rejected, such micro-launchers time and time again, and for good reasons?

This is a weapons system, guys, and not in terms of information warfare, either.

You are right it could be use in the anti-satellite role. But remember that is no difference between a ballistic missile and an orbital launcher other than the payload.

The commercial world does not have squadrons of F15s and F22s available for use as the first stage for micro-launchers. The launches can staged from any runway that can handle the F15 and the F22. AFAIK it just take a standardized ordnance rack and some software to enable this capability to launch a micro-sat or kinetic impactor to LEO.

Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Kryten on 06/28/2015 01:50 am
I have just found this article on SALVO with an artist impression:

http://www.americaspace.com/?p=83211
This image is not of SALVO, it's an early ALASA concept. (http://www.citizensinspace.org/2012/04/airborne-launch-assist-space-access/)
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Skyrocket on 10/11/2015 10:26 am
Any info, when the SALVO will fly?

The last news from Ventions was in September, when they successfully conducted a static fire test of electric pump-fed SALVO stage.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: jongoff on 10/12/2015 05:01 pm
Any info, when the SALVO will fly?

The last news from Ventions was in September, when they successfully conducted a static fire test of electric pump-fed SALVO stage.

DARPA's public release process is time consuming enough that it tends to put a damper on talking about work they fund. It takes 30 days to get approval for just about anything, including a tweet or a short blog post.

That said, knowing that this is DARPA you should expect some changes in direction occasionally...

~Jon
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Kryten on 05/01/2016 10:44 am
After months of silence, a new update from Ventions;
Quote
Ventions awarded 2 DARPA contracts for on-going development of electric-pump fed propulsion and launch vehicle stage technologies.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Skyrocket on 11/18/2016 03:34 pm
Has anyone heard any news on SALVO? Still active development or has it died together with Boeing's ALASA?
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: russianhalo117 on 11/18/2016 05:17 pm
Has anyone heard any news on SALVO? Still active development or has it died together with Boeing's ALASA?
Ventions has a one year contract for SALVO since April 2016 but that is the last mention of it by all partners in the project.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Skyrocket on 12/02/2021 09:23 am
Some time ago, a SALVO rocket has been spotted in Astra Space's factory.

Before this, only a extremly low resolution photo of SALVO was found in a DARPA powerpoint presentation.

https://twitter.com/Astra/status/1405950229388595202
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Celeste_El on 12/05/2021 07:02 pm
SALVO was a really wild concept. Based on information in patent US9745063B2 filed by Adam London and some of the other former Ventions members, what you see in the pictures mostly isn't the rocket. The rocket itself was going to be held inside an outer shell type thing (Fig.19A) which would reduce structural loads during takeoff and deployment as well as keeping the propellant cool during a possibly lengthy flight to the drop zone. Upon deployment the rocket would ditch the outer shell, sliding out the top and continuing to orbit (Fig.23). Its truly a wild concept and I highly suggest looking through the patent.
Also, I also found an old tweet with a much higher quality image of the prototype sitting in their factory.
https://twitter.com/mattfellowship/status/1289278441993322497 (https://twitter.com/mattfellowship/status/1289278441993322497)
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Skyrocket on 12/05/2021 07:26 pm
SALVO was a really wild concept. Based on information in patent US9745063B2 filed by Adam London and some of the other former Ventions members, what you see in the pictures mostly isn't the rocket. The rocket itself was going to be held inside an outer shell type thing (Fig.19A) which would reduce structural loads during takeoff and deployment as well as keeping the propellant cool during a possibly lengthy flight to the drop zone. Upon deployment the rocket would ditch the outer shell, sliding out the top and continuing to orbit (Fig.23). Its truly a wild concept and I highly suggest looking through the patent.

Thank you very much - this aspect of SALVO was not known to me.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Skyrocket on 12/05/2021 07:42 pm
SALVO was a really wild concept. Based on information in patent US9745063B2 filed by Adam London and some of the other former Ventions members, what you see in the pictures mostly isn't the rocket. The rocket itself was going to be held inside an outer shell type thing (Fig.19A) which would reduce structural loads during takeoff and deployment as well as keeping the propellant cool during a possibly lengthy flight to the drop zone. Upon deployment the rocket would ditch the outer shell, sliding out the top and continuing to orbit (Fig.23). Its truly a wild concept and I highly suggest looking through the patent.

The patent document US 9,745,063 B2 attached as pdf.

Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Celeste_El on 12/05/2021 11:38 pm
Yeah, it was a cool rocket. The test article in the factory doesn't get enough love and seems to get moved around a lot. Spotted it in the background of the latest factory tour so its still kicking around.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Celeste_El on 05/03/2022 06:49 am
Found a Facebook post from March 25, 2022, presumably from a party Astra threw after their first successful commercial launch. By far one of the best photos I've been able to find of the rocket.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Steven Pietrobon on 05/03/2022 07:57 am
The back end of the rocket looks pretty empty. Is this just a model of the rocket?
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Skyrocket on 05/03/2022 08:01 am
The back end of the rocket looks pretty empty. Is this just a model of the rocket?

No, this is just the end of the aerodynamic shell. The SALVO rocket itself is inside the shell. The only visible part of the SALVO rocket is the gray payload fairing. A few posts up in this thread are some drawings of the configuration.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Celeste_El on 09/28/2022 06:54 am
Found some more pictures of SLAVO hardware during development. Picture is taken from a presentation to NASA about the possibility of using electric pump fed engines for the MAV (linked below). It seems the rocket was slated to have two individually electric pumped 4.5 kN Lox/Kerosene engines. Its interesting seeing how much hardware they had ultimately built for the rocket. Makes me wonder truly how close it was to flying.
Title: Re: DARPA SALVO (Small Air Launch Vehicle to Orbit)
Post by: Celeste_El on 09/28/2022 07:38 am
I FOUND IT! I finally found that blurry photo of SALVO mounted under the F-15. It was posted on one of the former engineers LinkedIn page.

Edit: Found the full version of the bottom photo