Author Topic: RV-X  (Read 7337 times)

Offline lucspace

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RV-X
« on: 01/10/2018 02:11 PM »
As reported on http://danielmarin.naukas.com/2018/01/10/rv-x-un-prototipo-de-cohete-reutilizable-japones/, Mitsubishi Heavy Industries and JAXA are developing a DC-X-like test vehicle.

Offline john smith 19

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Re: RV-X
« Reply #1 on: 01/10/2018 03:39 PM »
As reported on http://danielmarin.naukas.com/2018/01/10/rv-x-un-prototipo-de-cohete-reutilizable-japones/, Mitsubishi Heavy Industries and JAXA are developing a DC-X-like test vehicle.
Interesting site. Google translate seems to handle it quite well.

It does in deed look like a smaller DC-X (with 4x roughly 11Klb engines replacing the RL10's) , and flies a roughly similar flight path.

People forget 3 things about DC-X
1) It was built by SDIO, IE customer driven, not supplier driven design.
2) It's core mission was to evolve a design for rapid and complete deployment of a space based ABM system, at least the sensor packages for it.
3) SDIO were OK with a nose first entry because they had an ICBM warehead development background.

If you wanted to run the process in reverse, tuning up an ICBM warehead design from a reusable test vehicle, this would be the sort of shape you'd want.

Who has had an argumentative neigbor recently overfly their territory with a rocket designed to carry a nuclear weapon?

BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Offline Kansan52

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Re: RV-X
« Reply #2 on: 01/10/2018 03:55 PM »
The part about the OOEX is intriguing.

Online ChrisWilson68

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Re: RV-X
« Reply #3 on: 01/10/2018 04:13 PM »
It's a step in the right direction.  I'd prefer to see more commitment to this direction and more resources put toward it, but at least it's something in the right direction.

Offline Bob Shaw

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Re: RV-X
« Reply #4 on: 01/10/2018 04:23 PM »
Isn't it nice to see rockets which look like Heinlein & Co intended?!?

Offline Kosmos2001

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Re: RV-X
« Reply #5 on: 01/10/2018 04:50 PM »
Interesting site. Google translate seems to handle it quite well.

It is one of the best sites about space and stuff in Spanish language. The articles are always a great reading.

Offline john smith 19

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Re: RV-X
« Reply #6 on: 01/10/2018 05:57 PM »
Isn't it nice to see rockets which look like Heinlein & Co intended?!?
Unfortunately all those spiffy VTOL SSTO designs IRL come with a 66-71% reduction in payload over a VTO TSTO design.

If people are OK with that then game on.
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Offline TrevorMonty

Re: RV-X
« Reply #7 on: 01/10/2018 08:00 PM »
This test bed vehicle, production RLV could look totally different. At least Japan and Europe are starting down RLV path even if it is only test bed vehicles.

Offline ellerdrop

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Re: RV-X
« Reply #8 on: 01/10/2018 09:36 PM »
there was a topic on this issue on this site, but it get deleted because of our ultra intelligent moderation team. i am sure they were testing this type of vehicle since 2009. there was even a twitter-account dedicated to it in japanese. nihonjin friends were translating it time to time. anyone remember?

Online russianhalo117

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Re: RV-X
« Reply #9 on: 01/10/2018 09:39 PM »
there was a topic on this issue on this site, but it get deleted because of our ultra intelligent moderation team. i am sure they were testing this type of vehicle since 2009. there was even a twitter-account dedicated to it in japanese. nihonjin friends were translating it time to time. anyone remember?
You mean this thread of RV-X's predecessor called RVT: https://forum.nasaspaceflight.com/index.php?topic=19571.0
« Last Edit: 01/10/2018 09:55 PM by russianhalo117 »

Offline Lar

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Re: RV-X
« Reply #10 on: 01/10/2018 09:48 PM »
Isn't it nice to see rockets which look like Heinlein & Co intended?!?
Unfortunately all those spiffy VTOL SSTO designs IRL come with a 66-71% reduction in payload over a VTO TSTO design.

If people are OK with that then game on.

I thought it was a lot worse than that... that most SSTO end up with negative payload fractions unless built with large quantities of unobtainium...

BUT if 66% is achievable(which I doubt), it might not be a bad idea to pursue this... NewSpace are teaching us that it's about cost, primarily, and a bigger rocket isn't necessarily more expensive in the long run
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Offline ellerdrop

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Re: RV-X
« Reply #11 on: 01/10/2018 09:58 PM »
there was a topic on this issue on this site, but it get deleted because of our ultra intelligent moderation team. i am sure they were testing this type of vehicle since 2009. there was even a twitter-account dedicated to it in japanese. nihonjin friends were translating it time to time. anyone remember?
You mean this thread of RV-X's predecessor called RVT: https://forum.nasaspaceflight.com/index.php?topic=19571.0

it was RVT but it was talked in 2013, i guess. and as i said there waas a dedicated twitter acoount to it. but i don't remember MHI's involvement

Online russianhalo117

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Re: RV-X
« Reply #12 on: 01/10/2018 10:35 PM »
there was a topic on this issue on this site, but it get deleted because of our ultra intelligent moderation team. i am sure they were testing this type of vehicle since 2009. there was even a twitter-account dedicated to it in japanese. nihonjin friends were translating it time to time. anyone remember?
You mean this thread of RV-X's predecessor called RVT: https://forum.nasaspaceflight.com/index.php?topic=19571.0

it was RVT but it was talked in 2013, i guess. and as i said there waas a dedicated twitter acoount to it. but i don't remember MHI's involvement
MHI I think was responsible for engines.

Online Steven Pietrobon

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Re: RV-X
« Reply #13 on: 01/11/2018 03:32 AM »
I did a study on SSTO a while back. My conclusion was that it was possible, provided you didn't use hydrolox due to its low impulse density. Just about any propellant combination (except hydrolox) worked, but kerolox gave the best performance using non-exotic propellants. Unfortunately, the Japanese are using hydrolox, probably due that to being the only low thrust engine they have. Changing to methalox would considerably improve performance though. Link to my paper below.

http://www.sworld.com.au/steven/pub/nsto.pdf
« Last Edit: 01/11/2018 03:36 AM by Steven Pietrobon »
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Online Lars-J

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Re: RV-X
« Reply #14 on: 01/11/2018 05:02 AM »
I did a study on SSTO a while back. My conclusion was that it was possible, provided you didn't use hydrolox due to its low impulse density. Just about any propellant combination (except hydrolox) worked, but kerolox gave the best performance using non-exotic propellants. Unfortunately, the Japanese are using hydrolox, probably due that to being the only low thrust engine they have. Changing to methalox would considerably improve performance though. Link to my paper below.

http://www.sworld.com.au/steven/pub/nsto.pdf

Interesting! When did you write this paper? And what might be different in your proposal if you wrote it today?

Offline pnetmon

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Re: RV-X
« Reply #15 on: 01/11/2018 06:23 AM »
http://www.mhi.com/company/technology/review/Vol.54No.4/abstracte-54-4-33.html
Mitsubishi Heavy Industries Technical Review Vol. 54 No. 4 (December 2017)
Technology Demonstration for the Development of Reusable Launch Vehicle
jp http://www.mhi.com/company/technology/review/pdf/544/544038.pdf
RV-X - Reusable Vehicle - eXperiment


http://www.mhi.com/company/technology/review/Vol.51No.4/abstracte-51-4-21.html
Mitsubishi Heavy Industries Technical Review Vol. 51 No. 4 (2014)
Status of Research and Development Activities on Reusable Launch Vehicle
jp http://www.mhi.com/company/technology/review/pdf/514/514044.pdf




« Last Edit: 01/11/2018 06:42 AM by pnetmon »

Offline john smith 19

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Re: RV-X
« Reply #16 on: 01/11/2018 08:43 AM »
I did a study on SSTO a while back. My conclusion was that it was possible, provided you didn't use hydrolox due to its low impulse density. Just about any propellant combination (except hydrolox) worked, but kerolox gave the best performance using non-exotic propellants. Unfortunately, the Japanese are using hydrolox, probably due that to being the only low thrust engine they have. Changing to methalox would considerably improve performance though. Link to my paper below.

http://www.sworld.com.au/steven/pub/nsto.pdf
I can't get a connection to your server.

Are you talking about VTO SSTO, VTHL SSTO or HTHL SSTO?
IIRC you did a propellant study that reckoned Propyne was pretty good but I'm surprised peopled don't factor in changing MR during the ascent, trading instantaneous Isp for being able to lose mass faster by burning off more of the denser propellant (usually the oxidizer if it's LOX or HTP).
That trick, applied to the Saturn V was responsible for 50% of the mass increase to LLO over the life of the programme (and it only applied to the 2nd and ED stages).
I thought it was a lot worse than that... that most SSTO end up with negative payload fractions unless built with large quantities of unobtainium...

BUT if 66% is achievable(which I doubt), it might not be a bad idea to pursue this... NewSpace are teaching us that it's about cost, primarily, and a bigger rocket isn't necessarily more expensive in the long run
You have it backwards. That's a 66% (up to 71%) loss in payload over for a VTO SSTO Vs a VTO TSTO.

Roughly speaking TSTO payload fraction is 3-3.5% of GTOW. Historically SSTO designs (all VTO AFAIK) have settled for delivering about 1% of GTOW. Shuttle was novel in that the 55 000 lb in the payload bay was about 1.4% of GTOW of the stack. So a not SSTO semi RLV with a near SSTO payload fraction. But very impressive for the budget. 

There is only one known SSTO design that does not compromise and aims to deliver full VTO TSTO performance. Everything else seems to be more or less modeled on Philip Bono's proposals (although probably without the Beryllium alloys at 200x the cost of Aluminum) with low aspect ratios and LH2 as fuel.
« Last Edit: 01/11/2018 08:51 AM by john smith 19 »
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Online Steven Pietrobon

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Re: RV-X
« Reply #17 on: 01/12/2018 08:10 AM »
Interesting! When did you write this paper?

I wrote that in 1998. Gee, how time flies. That was 20 years ago! I presented this at the IAC in Melbourne and then had it published in JBIS.

Quote
And what might be different in your proposal if you wrote it today?

I think about that quite often. If I was the "Big Man" in charge of my own space company, it would be a vertical landing first stage using 98% HTP/Syntin with seven 2.5 MN staged combustion engines. Stage structure would be carbon fibre. This results in a compact stage that will have zero problems due to cryogenic propellants. Liftoff thrust would be 17.5 MN.

For the second stage I'm still trying to decide between vertical or horizontal entry and either using hydrolox or methalox, although my current preference is vertical landing using hydrolox. For vertical entry the heat shield would have five holes with deployable doors. Engine nozzles extend to allow operation at both sea level and vacuum for best performance while also reducing interstage height. To increase heat shield area, eight "petals" would attach at base and extend for re-entry. Disadvantage is that mechanical complexity is quite high but eliminates need for header tanks and main loads are only vertical. Due to cryogenic temperatures I would used Al-Li for the tanks and composites for other structures. As a starting point, there would be five 250 kN hydrolox staged combustion (or expander if that is feasible) engines. I chose hydrolox as it gives 20% better performance than methalox and as the second stage is small, the overall dry mass increase is small. The Moon also has abundant oxygen, so the greater 5.5:1 mixture ratio of hydrolox compared to 3.5:1 for methalox and the greater performance of hydrolox means that much less fuel is required from the Earth. Another advantage of vertical is that it makes it easier for launch abort of crewed missions.

If the above gets me 30 t to LEO that would be great. With on-orbit refuelling, Lunar and Mars can be done using on-orbit refuelling and with full reusability! The smaller size of the vehicle with 12 engines should also be much cheaper for commercial missions than the 37 engined behemoth from you-know-who. :-)
« Last Edit: 01/12/2018 08:22 AM by Steven Pietrobon »
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Online Steven Pietrobon

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Re: RV-X
« Reply #18 on: 01/12/2018 08:19 AM »
I can't get a connection to your server.

Ahh, you must be from a European country! For some reason my website keeps getting black balled by certain European countries (I'm pointing my finger at you Germany!). Can you let me know which country you are from so that I can get the problem fixed? PM me if you want to keep that private. In the mean time, I've attached the paper.

Quote
Are you talking about VTO SSTO, VTHL SSTO or HTHL SSTO?

My paper was on VTHL.
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Offline Asteroza

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Re: RV-X
« Reply #19 on: 01/15/2018 12:01 AM »
there was a topic on this issue on this site, but it get deleted because of our ultra intelligent moderation team. i am sure they were testing this type of vehicle since 2009. there was even a twitter-account dedicated to it in japanese. nihonjin friends were translating it time to time. anyone remember?
You mean this thread of RV-X's predecessor called RVT: https://forum.nasaspaceflight.com/index.php?topic=19571.0

The twitter handle for the RVT related engine tests seems to have gone dark circa 2015

https://twitter.com/spacelark_jaxa

There was an interesting rumor that Mr Inatani, who was heavily involved with RVT work, is an advisor for Canon Electronics Inc. in some capacity, and that they were somehow involved with the avionics for the next RVT vehicle despite the MHI lead...

Offline Lar

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Re: RV-X
« Reply #20 on: 01/15/2018 12:16 AM »
I thought it was a lot worse than that... that most SSTO end up with negative payload fractions unless built with large quantities of unobtainium...

BUT if 66% is achievable(which I doubt), it might not be a bad idea to pursue this... NewSpace are teaching us that it's about cost, primarily, and a bigger rocket isn't necessarily more expensive in the long run
You have it backwards. That's a 66% (up to 71%) loss in payload over for a VTO SSTO Vs a VTO TSTO.

No I don't. I am saying a 66% loss is impressive and I doubt, based on nothing at all (IANARS), it's achievable. I would expect negative mass fractions or maybe a 98% loss or some such.

a 66% loss (in a fuel rich architecture) means that such a vehicle is worth pursueing.
« Last Edit: 01/15/2018 12:28 AM by Lar »
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Online russianhalo117

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Re: RV-X
« Reply #21 on: 01/15/2018 04:16 AM »
there was a topic on this issue on this site, but it get deleted because of our ultra intelligent moderation team. i am sure they were testing this type of vehicle since 2009. there was even a twitter-account dedicated to it in japanese. nihonjin friends were translating it time to time. anyone remember?
You mean this thread of RV-X's predecessor called RVT: https://forum.nasaspaceflight.com/index.php?topic=19571.0

The twitter handle for the RVT related engine tests seems to have gone dark circa 2015

https://twitter.com/spacelark_jaxa

There was an interesting rumor that Mr Inatani, who was heavily involved with RVT work, is an advisor for Canon Electronics Inc. in some capacity, and that they were somehow involved with the avionics for the next RVT vehicle despite the MHI lead...
Mr Inatani also seems to have connection to SS-520-4 launch failure and the upcoming SS-520-5 launch attempt of which Canon Electronics Inc. is a part of along with JAXA's ISAS.

Offline Always out of base

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Re: RV-X
« Reply #22 on: 08/17/2018 02:34 PM »
This is the latest status of RV-X and CALLISTO.
http://www.jaxa.jp/press/2018/08/files/20180802_CALLOSTO.pdf
RV-X; Test flight until 2019 Mar at Noshiro Rocket Testing Center
CALLISTO; Test flight in 2020 at Guiana Space Centre

Offline Asteroza

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Re: RV-X
« Reply #23 on: 08/20/2018 12:40 AM »
This is the latest status of RV-X and CALLISTO.
http://www.jaxa.jp/press/2018/08/files/20180802_CALLOSTO.pdf
RV-X; Test flight until 2019 Mar at Noshiro Rocket Testing Center
CALLISTO; Test flight in 2020 at Guiana Space Centre


This starts to explain some of the stuff about JAXA/Prof Ishitani being involved with Callisto.

It seems the current plan is to fly by the end of 2018 RV-X to 100m, and send results data to ESA to inform Callisto development, with JAXA getting Callisto data back.

Didn't think RV-X was that far along, but if the PDF images are any indication, the test vehicle assembly is pretty far along.


It's pretty telling that JAXA/ESA feel so compelled to demonstrate capabilities equivalent to Falcon 9 first stage. They are now in a race between chinese efforts and Blue Origin to get an operational reusable first stage. Though Callisto is more immediately usable as a booster, but RV-X is LOx/LH2 which makes it poorly suited for booster/first stage work.

Offline Asteroza

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Re: RV-X
« Reply #24 on: 11/16/2018 12:00 AM »
There was a MHI puff piece on Ars, which mentioned RV-X indirectly.

https://arstechnica.com/science/2018/11/long-on-tradition-japan-grapples-with-a-rapidly-changing-rocket-industry/

If you ignore the article closing on a dig about japanese inequality, there are some interesting nuggets from the MHI press junket. Notably they are trying to get H-3 down in price to compete with Falcon 9 (though that presupposes Falcon-9 not getting any cheaper, nor the looming specter of BFR/BFS), and a 8/year flight rate (which would make for a tightly packed schedule since the fisherman cooperatives effectively close Tangashima for half the year).

There is a sense that the gutting of the GEO market due to the new megaconstellations caught MHI flatfooted as they were too far along on H-3 work. There is the implication that a H-3 follow-on is going to try to happen, though linguistically it's not clear if this is a (semi)reusable variant of H-3 or a clean sheet design. There is serious work being done on RV-X to feed into Callisto and vice versa, as the fear of SpaceX getting too far ahead on reusability is felt as real. This might suggest Callisto might not be exclusively an ESA affair, and perhaps may form the basis of something greater.

I would normally speculate this might imply JAXA/ESA Arianspace/MHI joint work on a Callisto based new reusable vehicle as a cost share, but both ESA and JAXA currently have a heavy emphasis on "domestic" assured access to space, which would go against such a partnership in theory.

Online Steven Pietrobon

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Re: RV-X
« Reply #25 on: 11/16/2018 04:51 AM »
I would normally speculate this might imply JAXA/ESA Arianspace/MHI joint work on a Callisto based new reusable vehicle as a cost share, but both ESA and JAXA currently have a heavy emphasis on "domestic" assured access to space, which would go against such a partnership in theory.

Perhaps they could share production of the reusable first stage, while each country makes their own second stage. Once a production run of first stages is made (say 10 for each country plus spares), you shouldn't need to rely on other countries.
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Online ChrisWilson68

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Re: RV-X
« Reply #26 on: 11/16/2018 06:33 AM »
I would normally speculate this might imply JAXA/ESA Arianspace/MHI joint work on a Callisto based new reusable vehicle as a cost share, but both ESA and JAXA currently have a heavy emphasis on "domestic" assured access to space, which would go against such a partnership in theory.

Perhaps they could share production of the reusable first stage, while each country makes their own second stage. Once a production run of first stages is made (say 10 for each country plus spares), you shouldn't need to rely on other countries.

They could also just share costs on development and then build two factories to build the same booster.

Offline Asteroza

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Re: RV-X
« Reply #27 on: 11/18/2018 11:31 PM »
They could also just share costs on development and then build two factories to build the same booster.

That's a beautiful thought, but has anyone done that recently? Even allegedly license built copies of aircraft always end up " customizing" some aspect (usually avionics) to give some work to a domestic supplier, usually with enough changes that end up creating an incompatibility between base and license built variants.

Say something "simple" like the choice of wiring spec (say ESA preferring spacewire for instance) for wiring up things has substantial downstream impacts.

Tags: JAXA RV-X RVT ESA Callisto RLV