On-line Document Troves

[Proponent]

In the interest of promoting better informed debate, here is a list of websites providing large numbers of space-related documents or abstracts thereof either free of charge or, where noted, at very low cost.

Corrections and additions, especially in the non-English-language category, are welcome.  I will update this post accordingly.

LATEST ADDITIONS:  National Security Archive (30 Nov 2021); Meadville Space Center and NASSP (9 Oct); Wilson Center Digital Archive (28 Apr); Air Force Space & Missile Museum (9 Nov 2020), Flight Global archive no longer free (27 Oct), Jonathan's Space Home Page (21 Aug), Air Force Magazine (26 Mar), Alternate Wars (30 Dec 2019), Ares Institute (3 Nov), ULA (3 Sep), Academia.edu (29 Aug), Federation of American Scientists (27 Aug) FlightGlobal; International Astronautical Congress papers (19 Aug), Aerospace Corporation and Planetary Society (12 Aug), tindallgrams.net (7 Aug).


Indications of Cost and Accessability
 !:  No cost            @:  Free registration with email address
$:  < US$10         $$:  US$10+
&:  Free to members or member institutions

Academia.edu @ $
Books, e.g., Charles Pooley's Microlaunchers, and academic papers.  Paid subscription allows full-text searches, enables alerts, provides more information about authors, etc.  Differs from ResearchGate in that one need not be a bona fide researcher.  Be forwarned that you will receive frequent emails alerting you to papers similar to any that you download.

AERADE Reports Archive at Cranfield University !
Technical reports, mostly aeronautical but some space-related, from the UK's former Aeronautical Research Council and predecessors and from the US's former NACA.

Aerospace Corporation's Center for Space Policy and Strategy !
Papers:  A searchable database of reports on a variety of space-related topics, mostly high-level and policy related.
Space Policy Archive:  Policy documents from governments around the world dating back to 1945.

Aerospace Projects Review $
Scott Lowther's large collection, not free but very reasonably priced.  Go about 60% of the way down the page for "Space Drawings" and below that find "Space Documents."  Note that a few of the documents for sale are available elsewhere at no cost.

Aerospace Research Central (AIAA) & $$
Publications of the American Institute of Aeronautics and Astronautics.  1st page, with abstract, is free -- non-members pay for full paper.

Air Force Magazine !
Articles all the way back to 1955 may be downloaded.

Air Force Space & Missile Museum Archives !
Library of the Air Force Space & Missile Museum at Cape Canaveral.

Alternate Wars !
Though devoted principally to military history, this site does have two sections of interest to space cadets: 
The Space Race: Documents and drawings focused on the Apollo era; and
Standard Aircraft Characteristics: Includes specs on the X-20 Dyna-Soar.

Ares Institute !
This site, discovered by JoeFromRIUSA, provides numerous documents of great interest.  Though many are also on NTRS, here they are highly browseable.  Well worth a look.
Historical documents;
NASA SP-8000 series vehicle-design criteria.

Apollo Flight Journal !
Hosted on NASA's history website, this is a companion to the Apollo Lunar Surface Journal, but covers all manned Apollo missions.

Apollo Lunar Surface Journal !
Transcripts and many other documents pertaining to the six Apollo missions the reach the moon's surface.

Apollo Preliminary Drawings !
High-resolution drawings of an early Apollo design from North American Aviation in 1961.

aRocket !
Though focused on amateur rocketry, the "Reference Desk" section (about a quarter of the way down the page) contains categorized links to many useful technical publications, both on- and off-line.

arXiv.org !
The physicists' pre-print server contains some papers of astronautical interest, e.g., those on the SWIMMER propulsion system or on alien-technology hypotheses for Tabby's Star and for fast radio bursts.

Astrophysics Data System !
Mostly astrophysics abstracts, but some full papers, some space related.

The Black Vault !
FOIA'ed documents.

CIA Archive !
Declassified CIA analyses.

COMSTAC Presentations Archive !
Presentations to the FAA's Commercial Space Transportation Advisory Committee.

Defense Technical Information Center (DTIC) !
DoD's answer to NTRS, though search options are not as extensive.  The holdings likely of most interest are the technical reports, though there are publicly accessible collections as well.

DLR elib !
Technical reports of Germany's space agency, the DLR (Deutsches Zentrum für Luft- und Raumfahrt).

EverySpec !
All sorts of US government specs, standards and handbooks.

Federation of American Scientists: Nuclear Resources !
Papers on space nuclear power and nuclear thermal propulsion.

FlightGlobal Archive $$
Searchable archive of articles appearing in the journal Flight International (originally Flight) back to 1909.  Although the focus is on aviation, many space-related articles are present.  As of October 2020 no longer free, but there is hope this will change.

FISO Archive !
Presentations (slides & audio) to NASA's Future In-Space Operations working group.  FISO's webmaster runs a tight ship:  don't carelessly download multiple copies of a file, or you might find your IP address blocked!

GAO !
US Government Accountability Office's reports, including some on NASA programs.

Heroic Relics !
Hardware designs from the early space age.

IDA's Science and Technology Policy Institute !
This arm of the Institute for Defense Analyses (IDA) is a think tank performing research for the US government since April 2012.  Some relevant research has also been performed by the IDA itself.  In either case, the focus is on issues affecting government policy, especially military.

International Astronautical Congress papers !
Many though not all of the papers presented at the International Astronautical Federation's annual congresses since 2012.

IAEA's International Nuclear Information System !
The International Atomic Energy Agency's archive, similar to that of DoE's OSTI, includes some papers beyond strictly nuclear topics.

Internet Archive ! (@ to borrow non-public-domain books)
All kinds of reports, books and magazines (Aviation Week and Missiles & Rockets), though many in the first category are also found on NTRS.  As with NTRS, enter at your peril!

Jonathan's Space Home Page !
Many of Jonathan's own publications and a collection of rare historical documents.

JBIS Archives $
Papers published since 1999 in the Journal of the British Interplanetary Society.  View first pages for free.  Use the "Archives" menu to browse by year.

JSTOR &
Has some technical journals (e.g., SAE Transactions) and books of interest.  Depending the institution to with which you may be affiliated or the country in which you reside, you may be able to view or download, subject to appropriate restrictions on usage.

LPRE.de !
Documents:  Soviet-era rocket-engine terminology, standards and patents (mostly in Russian).
Publications:  Handbooks, manuals, histories, etc. about Russian/Soviet engines (mostly in Russian).

Lunar and Planetary Institute !
Loads of scientific and technical documents, current and historical about the moon and lunar missions.

Meadville Space Center !
Documents about Mercury, Gemini and Apollo gathered by Robert Conley in connection with his historical add-ons for the stupendous Orbiter spaceflight simulator.

Muckrock !
FOIA'ed documents -- and a system for making your own FOIA requests.

NASSP on the Wayback Machine !
Principally Apollo-era documents regarding proposed manned systems that were never pursued, gathered in support of the the NASSP add-ons for the amazing Orbiter spaceflight simulator.  Many of the links were dead following, but NSF member libra found them with the Wayback Machine.

National Academies' Press, Space and Aeronautics @
Major studies, e.g., decadal surveys and the 2014 study by the NRC on uses of SLS in exploration.  Free to download but requires email address.

NASA !
History Publications:  Overview of types of NASA's history publications, including link to the President's Report, with handy summary of NASA's budget history.
History Series Publications: History books (SP-4000 series).
JPL Technical Reports Server
JSC History Portal
KSC Archive
Langley Archive:  With early manned spaceflight documents from the Space Task Group.
MSFC Archive:  Includes von Braun's weekly notes.
NASA Technical Reports Server (NTRS):  It's easy to spend hours and hours here ... beware!

National Archives !
While particularly strong on photos, the Archives has many space-related documents, a significant fraction being available online.  The advanced-search feature, linked to here, is by no means the only way to explore the Archive's collections.

National Security Archive !
Though space-related materials here pertain mostly to military and reconnaissance programs, civilian activities of geopolitical interest, e.g., Apollo, appear as well.  See, for example, the space-policy section.

NATO Science & Technology Organization !
Technical papers and proceedings.

Office of Scientific and Technical Information (OSTI) !
DoE's equivalent of NTRS and DTIC.  Particularly useful regarding early nuclear propulsion studies.

Office of Technology Assessment Archive !
Though Congress defunded the Office of Techonology Assessment in 1995, the Federation of American Scientists maintains an archive of its reports, a dozen or two of which relate to space.  OTA archives are also maintained by the University of North Texas and Princeton University.

Planetary Society's Resource Library !
Newsletters and press kits for planetary missions and for the Planetary Society's missiones (e.g., LightSail 2).  Also, extensive documentation on and breakdowns of historical NASA budgets (agency-wide, not just planetary-related), with two different inflation factors.

RAND Corporation ! $$
Various papers produced by the think tank, beginning with a 1946 report on a "World-Circling Spaceship." 
Most, though not all, reports are free.

ResearchGate @
Papers on a wide variety of subjects.  To participate, you must convince the ResearchGate that you are a genuine researcher.

SAE International & $$
A surprising number of early space-age papers were published by what was then known as the Society of Automotive Engineers.  2-page preview is free to view; non-members pay for a full paper.

ScribD @ $
Requires email address for sign-up (or paid subscription to download books, etc.).

Space Congress Proceedings !
Proceedings of the Space Congress, held annually since 1962.

SpacePolicyOnline.com !
Choose the "Reports" tab for Marcia Smith's own reports and summaries on the US government's deliberations and decisions about space, as well as for links to other organizations' reports.

STL Online Archive !
Papers, memos and other documents related to Space Technology Laboratories, a contractor involved in early space shots, later absorbed into TRW.

Техническая библиотека (TechLibrary) !
Large collection of downloadable technical books, including famous textbooks, e.g., Landau's & Lifshitz's physics series (in Russian).

tindallgrams.net !
A searchable on-line repository of Bill Tindall's brilliant memos about Apollo trajectories, GNC and mission planning, with links to sources of additional memos not yet included.  You can help by editing and adding tindallgrams.

ULA !
United Launch Alliance offers papers from the mid-2000's onward about various aspects of space technology, with a focus on commercial lunar architectures and in-space refueling.

University of Alabama in Huntsville Digital Collections !
Apollo Collection: Interesting, but strangely dominated by Project Highwater documents.
Saturn V Collection:  Mesmerizing.  Mostly, but not entirely, Saturn-related.

Virtual AGC !
Lots of documentation on Gemini and Apollo guidance and control systems.

Wilson Center Digital Archive !
Focused on international history, this archive contains two collections focused on Soviet documents related to space, many with English translations:
The Space Race Collection -- 1946-85,
The Yuri Gagarin Collection -- 1958-61.

[Proponent]

Just a note to highlight recently added links in the OP to the National Archives and UAH's Saturn V Collection.

The Saturn V collection had long been one of my favorites, but it seemed to have been taken off line.  At any rate, it's online now, and I believe it's been expanded.  It gives me that kid-in-candy-store feeling.  As an example, have a look at Goodyear Aircraft's 1962 proposal for manned lunar landings using Titan launch vehicles, Agena in-space stages, and inflatable rotating space stations in both LEO and LLO (attached to this post).

[Hobbes-22]

JPL Technical Reports Server (the JPL equivalent to the NTRS):

https://trs.jpl.nasa.gov/

[Proponent]

Thanks.  I'm wondering, though, whether there are any reports there that aren't on NTRS.  I've tried a few but but have found them all on NTRS as well.

[JoeFromRIUSA]

Thank you Proponent! I'm a bit saddened about the Saturn material though. Back in the day, it had much more Apollo related material. I even was able to download the Apollo 1 flight plan (now missing from my collection) . It's my particular Holy Grail as far as space-related documents go.

[Hobbes-22]

Thanks.  I'm wondering, though, whether there are any reports there that aren't on NTRS.  I've tried a few but but have found them all on NTRS as well.

I found the JPL site when looking for documents on JPL missions that I couldn't find on the NTRS.

[Hobbes-22]

Thank you Proponent! I'm a bit saddened about the Saturn material though. Back in the day, it had much more Apollo related material. I even was able to download the Apollo 1 flight plan (now missing from my collection) . It's my particular Holy Grail as far as space-related documents go.

Have you tried using the Wayback machine (archive.org) to access earlier versions of the Saturn website?

[Proponent]

I found the JPL site when looking for documents on JPL missions that I couldn't find on the NTRS.

Thanks.  I've added it to the OP.

BTW, Firefox gives me a SEC_ERROR_REVOKED_CERTIFICATE error when I try to connect, so I need to use a different browser to reach the site.  Is there a way to fix this problem within Firefox?

[mtakala24]

What a great thread! Deserves to be pinned at some point.

Should we include ones that are behind paywalls? Institutional users (students etc) might have access to those via their University libraries.

[Proponent]

Good point.  Some paywalled sources are already in the list.  I've added indications as to the availability.

[Graham2001]

The Virtual AGC Project website has a large collection of Apollo and Apollo AGC related documents.

Virtual AGC Project: Document Library Page

[libra]

A great and useful thread indeed.

[Proponent]

The Virtual AGC Project website has a large collection of Apollo and Apollo AGC related documents.

Virtual AGC Project: Document Library Page

A great source -- already in the list (see the very last entry).

[Proponent]

Bump to highlight the major addition of FlightGlobal (see revised OP).

[Proponent]

Because I understand it to be temporary, I'm not adding it to the OP, but the AIAA is currently making available full downloads of a couple of dozen classic Apollo-related papers.

[JoeFromRIUSA]

https://commons.erau.edu/space-congress-proceedings/

[libra]

A great resource that recently seemingly popped out of nowhere.

A "mythical" paper I long searched, and found there.

https://commons.erau.edu/space-congress-proceedings/proceedings-1966-3rd/session-2/1/

Apollo to asteroid 433 Eros, January 1975 !

[leovinus]

Per other thread there is also https://commons.erau.edu/space-congress-proceedings/

[Hobbes-22]

Bump to highlight the major addition of FlightGlobal (see revised OP).

Unfortunately, a few months ago FlightGlobal disabled access to the archive (following a sale of the company). They're considering making the archive accessible again, but that seems to be a long-term project.

[Proponent]

Per other thread there is also https://commons.erau.edu/space-congress-proceedings/

Already in the list, actually, as "Space Congress Proceedings !".

This does make me wonder, though, whether there is a better way of organizing the list to make things easier to find.