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.
Isn't it nice to see rockets which look like Heinlein & Co intended?!?
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?
Quote from: Bob Shaw on 01/10/2018 04:23 pmIsn'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.
Quote from: ellerdrop on 01/10/2018 09:36 pmthere 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
Quote from: russianhalo117 on 01/10/2018 09:39 pmQuote from: ellerdrop on 01/10/2018 09:36 pmthere 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=19571.0it 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
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 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
Interesting! When did you write this paper?
And what might be different in your proposal if you wrote it today?
I can't get a connection to your server.
Are you talking about VTO SSTO, VTHL SSTO or HTHL SSTO?
Quote from: Lar on 01/10/2018 09:48 pmI 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 runYou have it backwards. That's a 66% (up to 71%) loss in payload over for a VTO SSTO Vs a VTO TSTO.
Quote from: russianhalo117 on 01/10/2018 09:39 pmQuote from: ellerdrop on 01/10/2018 09:36 pmthere 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=19571.0The twitter handle for the RVT related engine tests seems to have gone dark circa 2015https://twitter.com/spacelark_jaxaThere 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...
This is the latest status of RV-X and CALLISTO.http://www.jaxa.jp/press/2018/08/files/20180802_CALLOSTO.pdfRV-X; Test flight until 2019 Mar at Noshiro Rocket Testing CenterCALLISTO; Test flight in 2020 at Guiana Space Centre
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.
Quote from: Asteroza on 11/16/2018 12:00 amI 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.
JAXA to start flight tests in June to develop reusable rocket techKYODO NEWS KYODO NEWS - Mar 7, 2020 - 15:38TOKYO - The Japan Aerospace Exploration Agency will begin flight tests in June to develop technology for the reuse of the first stages of launch vehicles, a government source said Saturday.
There were two static fires of RV-X, RV-X-1 and RV-X-2 in the late 2010s. I'm not sure what the current status is. Seems like JAXA have switched their interest to the ATRIUM engine; a combined cycle air breathing and rocket engine using hydrolox. There are two vehicles planned. A single ATRIUM engine version called FTB for 2024 and a triple ATRIUM engine version for 2027. If anyone can provide Japanese translations of the slides used in the video, that would be much appreciated!