Talk:H-II Transfer Vehicle

Simplicity
I think that the assumption that the HTV is simpler than the Progress since it performs berthing rather than docking like the Progress is by itself a rather simplistic statement.

The berthing requires station keeping of the HTV in the vicinity of the ISS, which is a risky operation. Grappling of a 15-ton free flying object by the SSRMS is an operation, which has never been attempted before.

It is not comparable to grappling of a satellite by the Shuttle arm, because Shuttle offers direct visibility and more maneuverability than the ISS.

A probable source for this page would be http://www.jaxa.jp/missions/projects/rockets/htv/index_e.html

H-II series
There should be an H-II series article about the program and related rockets. 70.55.89.134 (talk) 07:41, 12 April 2008 (UTC)

NASA Statement on Inaccurate Reports About Japanese Cargo Services
see http://www.nasa.gov/home/hqnews/2008/jul/HQ_08181_HTV_statement.html —Preceding unsigned comment added by 213.249.61.38 (talk) 17:27, 21 July 2008 (UTC)

Need to list volume of craft
Volume is listed on other unmanned re-supply craft's pages. Pressurized: 14m3 Unpressurized: 16m3 Total Volume: 30m3  --Craigboy (talk) 22:08, 14 February 2010 (UTC)
 * Agreed. But that link for the source you gave has gone dead.  If you have a good source so a verifiable citation could be added, you should just add the claim to the article.  Wikipedia works best when everyone is an editor.  Cheers. N2e (talk) 17:17, 15 November 2010 (UTC)

RV variant
according to SpaceflightNow, Japan is considering a re-entry return vehicle variant. 76.66.197.151 (talk) 04:27, 7 September 2010 (UTC)


 * JAXA's study reports on HTV-R in Japanese are here and here. There was a study report on other proposals too, but the link is now broken.
 * --Shinkansen Fan (talk) 02:36, 8 September 2010 (UTC)

MERGE / Rename / Links
The HTV series of spacecraft doesn't appear to have a parent article. If it does, it's not linked very well, I can't find it. Possibly Merging HTV-I and HTV-II articles is a solution to create a parent article for the whole lot. Referring to the HTV is important in other articles. Am I missing anything, is there a parent article ? Penyulap  talk 06:07, 23 June 2011 (UTC)


 * As I understand it, H-II Transfer Vehicle is the parent article for the two vehicle articles, HTV-1 and Kounotori 2. Is that what you asked?
 * I just made a new navigation box which we could consider posting on all three articles, if it helps, at HTV spaceflight.
 * --Hroðulf (or Hrothulf) (Talk) 10:04, 23 June 2011 (UTC)


 * Actually there is already a navigation box that should help readers: H-II Transfer Vehicles. It wasn't on one of the articles, but now is on all three. Perhaps we need something else further up the page: a succession box perhaps. --Hroðulf (or Hrothulf) (Talk) 16:47, 23 June 2011 (UTC)

Info and news
"The ONSP’s logic for re-auditing the HTV-R is harsh. As it is too expensive to commercialize, the H-2B will be ditched as dead once its HTV duties are finished. As the HTV’s only purpose is to service the International Space Station, and Japan must minimize its costs, then logically the HTV, HTV-R and H-2B have no future beyond 2016 and the HTV’s seventh flight. Indeed, one industry source tells Aviation Week that Japan may launch perhaps two, at most, post-2016 missions."

--Craigboy (talk) 03:39, 27 April 2013 (UTC)

Demise of the ATV
With the final flight of the ESA ATV that leaves the HTV as the largest and most capable supply vehicle to ISS, like the ATV was post shuttle. I assume that'll be added to the article after ATV-5 is re-entered and a cinder. Doyna Yar (talk) 03:59, 14 August 2014 (UTC)

Final 4 flights needed for batteries to extend ISS operations
[https://oig.nasa.gov/audits/reports/FY14/IG-14-031.pdf Extending the Operational Life of the International Space Station Until 2024. Sept 2014] on page 29 ("19") says "Battery Replacement Dependent on Japanese Vehicle. Another large set of ORUs that will need replacing to extend ISS operations are the Ni-H2 batteries that provide electricity when the Station is in the eclipse portion of its orbit. The batteries had an expected operational life of 6.5 years, which has been extended to 10 years by reconditioning and lower-than-expected drainage rates. The oldest batteries on Station have been operating since 2006 and the newest since 2010. Accordingly, replacements will be needed to extend ISS operations beyond 2020. NASA plans to replace the Ni-H2 batteries with newly designed Lithium-Ion batteries, which have a greater capacity to store energy. One of the new batteries will replace two Ni-H2 models. NASA plans to deliver 24 of the new batteries in a series of four launches between 2017 and 2020 using Japan’s H-II Transfer Vehicle (HTV). The Japanese provide the HTV to NASA as part of a barter arrangement to offset their portion of ISS operational costs. During the course of this audit, the Japanese verbally agreed to delay two previously scheduled HTV launches to accommodate battery delivery missions in 2016 and 2017 and to fly two additional missions in 2019 and 2020 to transport the remaining batteries. However, NASA officials told us the Japanese are reluctant to continue production of the HTV beyond 2020 because of the high cost of producing and operating the vehicle. With no HTV missions scheduled after 2020, NASA will lose the largest cargo vehicle currently available. Accordingly, if additional radiators and solar arrays are needed, NASA will have to either reduce the size of the ORUs or hope that commercial cargo vessels capable of transporting larger equipment are available" (I dont have Japanese sources to confirm) - Rod57 (talk) 10:58, 5 May 2017 (UTC)


 * Please read H-II_Transfer_Vehicle. --Fukumoto (talk) 14:04, 5 May 2017 (UTC)
 * I have, but why ? Does it confirm or contradict the NASA PDF ? - Rod57 (talk) 07:11, 27 November 2018 (UTC)

Mass at launch
The given source dosn't say anything about mass at launch. I presume this is a sum of spacecraft mass and payload mass. But the source doesn't say whatever 10,5 Mg is a total structural mass or including fuel for spacecraft itself. So launch mass could be higher. Elk Salmon (talk) 11:07, 4 November 2018 (UTC)


 * For your info, H-IIB launch vehicle's launch capability is 16.5 t for the HTV orbit.

Protected during launch by the H2B payload fairing
Looks like it is always protected during launch by the H2B payload fairing - Article could say. - Rod57 (talk) 07:05, 27 November 2018 (UTC)

Cost
Article does not seem to give a cost for HTV. It says HTV-X is intended to reduce cost, but by how much ? - Rod57 (talk) 07:21, 27 November 2018 (UTC)

A Commons file used on this page or its Wikidata item has been nominated for deletion
The following Wikimedia Commons file used on this page or its Wikidata item has been nominated for deletion: Participate in the deletion discussion at the. —Community Tech bot (talk) 15:51, 16 February 2020 (UTC)
 * JAXA HTV-X.jpg

Splitting proposal
I propose that section H-II Transfer Vehicle be split into a separate page called HTV-X. --Fukumoto (talk) 12:45, 4 March 2021 (UTC)


 * Agree with split. Happy to do split. Gusfriend (talk) 07:33, 26 January 2022 (UTC)


 * The split has been completed and is now at HTV-X. Gusfriend (talk) 03:00, 30 January 2022 (UTC)


 * It is somewhat unfortunate timing since the delay of the development of H3 Launch Vehicle was announced recently, we don't know when the HTV-X1 is going to be launched. --Fukumoto (talk) 04:42, 30 January 2022 (UTC)