Editing Rocket (section)

==Costs and economics==
The costs of rockets can be roughly divided into propellant costs, the costs of obtaining and/or producing the 'dry mass' of the rocket, and the costs of any required support equipment and facilities.<ref name=aday>[http://www.fourmilab.ch/documents/rocketaday.html "A Rocket a Day Keeps the High Costs Away"] {{webarchive|url=https://web.archive.org/web/20081103045215/http://www.fourmilab.ch/documents/rocketaday.html |date=2008-11-03 }} by John Walker. September 27, 1993.</ref>

Most of the takeoff mass of a rocket is normally propellant. However propellant is seldom more than a few times more expensive than gasoline per kilogram (as of 2009 gasoline was about {{convert|1|$/kg|abbr=on|disp=sqbr}} or less), and although substantial amounts are needed, for all but the very cheapest rockets, it turns out that the propellant costs are usually comparatively small, although not completely negligible.<ref name=aday/> With liquid oxygen costing {{convert|0.15|$/kg}} and liquid hydrogen {{convert|2.20|$/kg|abbr=on}}, the [[Space Shuttle]] in 2009 had a liquid propellant expense of approximately $1.4 million for each launch that cost $450 million from other expenses (with 40% of the mass of propellants used by it being liquids in the [[external fuel tank]], 60% solids in the [[Space Shuttle Solid Rocket Booster|SRBs]]).<ref>{{cite web |url=http://www-pao.ksc.nasa.gov/kscpao/nasafact/pdf/ssp.pdf |title=Space Shuttle Use of Propellants and Fluids |publisher=NASA |access-date=2011-04-30 |url-status=dead |archive-url=https://web.archive.org/web/20111017180215/http://www-pao.ksc.nasa.gov/kscpao/nasafact/pdf/SSP.pdf |archive-date=October 17, 2011 }}</ref><ref>{{cite web |url=http://www-pao.ksc.nasa.gov/nasafact/count2.htm |title=NASA Launch Vehicles and Facilities |publisher=NASA |access-date=2011-04-30 |url-status=dead |archive-url=https://web.archive.org/web/20110427020520/http://www-pao.ksc.nasa.gov/nasafact/count2.htm |archive-date=2011-04-27 }}</ref><ref>{{cite web |url=http://www.nasa.gov/centers/kennedy/about/information/shuttle_faq.html |title=Space Shuttle and International Space Station |publisher=NASA |access-date=2011-04-30 |url-status=live |archive-url=https://web.archive.org/web/20110507113329/http://www.nasa.gov/centers/kennedy/about/information/shuttle_faq.html |archive-date=2011-05-07 }}</ref>

Even though a rocket's non-propellant, dry mass is often only between 5–20% of total mass,<ref>{{cite web |url=http://www.spacetethers.com/massfraction.html |title=Mass Fraction |publisher=Andrews Space and Technology (original figure source) |access-date=2011-04-30 |url-status=dead |archive-url=https://web.archive.org/web/20120425073303/http://www.spacetethers.com/massfraction.html |archive-date=2012-04-25 }}</ref> nevertheless this cost dominates. For hardware with the performance used in orbital [[launch vehicle]]s, expenses of $2000–$10,000+ per kilogram of [[dry weight]] are common, primarily from engineering, fabrication, and testing; raw materials amount to typically around 2% of total expense.<ref>Regis, Ed (1990), ''Great Mambo Chicken And The Transhuman Condition: Science Slightly Over The Edge'', Basic Books, {{ISBN|0-201-56751-2}}. [http://groups.google.com/group/sci.space/browse_thread/thread/dcc29174a504c200/7e68102f0a014325?hl=en&ie=UTF-8&oe=utf-8&q Excerpt online]</ref><ref name = CheapRockets>[[:File:LEOonthecheap.pdf|U.S. Air Force Research Report No. AU-ARI-93-8: LEO On The Cheap]]. Retrieved April 29, 2011.</ref> For most rockets except reusable ones (shuttle engines) the engines need not function more than a few minutes, which simplifies design.

Extreme performance requirements for rockets reaching orbit correlate with high cost, including intensive quality control to ensure reliability despite the limited [[safety factor]]s allowable for weight reasons.<ref name=CheapRockets/> Components produced in small numbers if not individually machined can prevent amortization of R&D and facility costs over mass production to the degree seen in more pedestrian manufacturing.<ref name=CheapRockets/> Amongst liquid-fueled rockets, complexity can be influenced by how much hardware must be lightweight, like pressure-fed engines can have two orders of magnitude lesser part count than pump-fed engines but lead to more weight by needing greater tank pressure, most often used in just small maneuvering thrusters as a consequence.<ref name=CheapRockets/>

To change the preceding factors for orbital launch vehicles, proposed methods have included mass-producing simple rockets in large quantities or on large scale,<ref name=aday/> or developing [[reusable launch system|reusable rockets]] meant to fly very frequently to amortize their up-front expense over many payloads, or reducing rocket performance requirements by constructing a [[non-rocket spacelaunch]] system for part of the velocity to orbit (or all of it but with most methods involving some rocket use).

The costs of support equipment, range costs and launch pads generally scale up with the size of the rocket, but vary less with launch rate, and so may be considered to be approximately a fixed cost.<ref name=aday/>

Rockets in applications other than launch to orbit (such as military rockets and [[JATO|rocket-assisted take off]]), commonly not needing comparable performance and sometimes mass-produced, are often relatively inexpensive.

===2010s emerging private competition===
{{Further|Space launch market competition#2010s: Competition and pricing pressure}}
Since the early 2010s, new [[private spaceflight|private options]] for obtaining spaceflight services emerged, bringing substantial [[market competition|price pressure]] into the existing market.<ref name=bbc20141203>{{cite news |title=Europe to press ahead with Ariane 6 rocket |url=https://www.bbc.com/news/science-environment-30251863 |work=BBC News |access-date=2015-06-25 |first=Jonathan |last=Amos |date=3 December 2014}}</ref><ref name=fp20131209>{{cite news |last=Belfiore |first=Michael |title=The Rocketeer |url=https://foreignpolicy.com/articles/2013/12/02/the_rocketeer_elon_musk |access-date=2013-12-11 |newspaper=Foreign Policy |date=2013-12-09 |archive-date=2013-12-10 |archive-url=https://web.archive.org/web/20131210233009/http://www.foreignpolicy.com/articles/2013/12/02/the_rocketeer_elon_musk |url-status=dead }}</ref><ref name=wsj20150917>
{{cite news |last1=Pasztor|first1=Andy |url=https://www.wsj.com/articles/u-s-rocket-supplier-looks-to-break-short-leash-1437339519 |work=[[The Wall Street Journal]] |title=U.S. Rocket Supplier Looks to Break 'Short Leash' |date=2015-09-17 |access-date=2015-10-14 |quote=The aerospace giants [Boeing Co. and Lockheed Martin Corp.] shared almost $500 million in equity profits from the rocket-making venture last year, when it still had a monopoly on the business of blasting the Pentagon's most important satellites into orbit.  But since then, 'They've had us on a very short leash,' Tory Bruno, United Launch's chief executive, said. }}</ref><ref name=wapo20160819>{{cite news |last=Davenport|first=Christian |url=https://www.washingtonpost.com/business/economy/the-billionaire-space-barons-and-the-next-giant-leap/2016/08/19/795a4012-6307-11e6-8b27-bb8ba39497a2_story.html |title=The inside story of how billionaires are racing to take you to outer space |newspaper=[[Washington Post]] |date=2016-08-19 |access-date=2016-08-20 |quote=the government's monopoly on space travel is over}}</ref>