Editing Atmospheric entry (section)

=={{anchor|IRDT}} Inflatable heat shield entry==

Deceleration for atmospheric reentry, especially for higher-speed Mars-return missions, benefits from maximizing "the drag area of the entry system. The larger the diameter of the aeroshell, the bigger the payload can be."<ref name=nasa20090817/> An inflatable aeroshell provides one alternative for enlarging the drag area with a low-mass design.

===Russia===

Such an inflatable shield/aerobrake was designed for the penetrators of [[Mars 96]] mission. Since the mission failed due to the launcher malfunction, the NPO Lavochkin and DASA/ESA have designed a mission for Earth orbit. The Inflatable Reentry and Descent Technology (IRDT) demonstrator was launched on Soyuz-Fregat on 8 February 2000. The inflatable shield was designed as a cone with two stages of inflation. Although the second stage of the shield failed to inflate, the demonstrator survived the orbital reentry and was recovered.<ref name=IRDT2000>{{Cite web|url=http://www.esa.int/esapub/bulletin/bullet103/marraffa103.pdf|title=Inflatable Re-Entry Technologies: Flight Demonstration and Future Prospects|access-date=April 22, 2011|archive-date=January 29, 2012|archive-url=https://web.archive.org/web/20120129130903/http://www.esa.int/esapub/bulletin/bullet103/marraffa103.pdf|url-status=live}}</ref><ref>[http://www.spaceflight.esa.int/irdt/factsheet.pdf Inflatable Reentry and Descent Technology (IRDT)] {{webarchive|url=https://web.archive.org/web/20151231130516/http://www.spaceflight.esa.int/irdt/factsheet.pdf |date=2015-12-31 }} Factsheet, ESA, September, 2005</ref> The subsequent missions flown on the [[Volna]] rocket failed due to launcher failure.<ref name=2R2Smissions>{{Cite web|url=https://www.2r2s.com/|archive-url=https://web.archive.org/web/20161207150236/http://www.2r2s.com/demo_missions.html |url-status=dead |title=The Demonstration Missions|archive-date=December 7, 2016|website=www.2r2s.com|publisher=Return and Rescue Space Systems GmbH}}</ref>

===NASA IRVE ===
[[File:Inflatable Re-entry Vehicle Experiment.jpg|thumb|right|NASA engineers check IRVE.]]
NASA launched an inflatable heat shield experimental spacecraft on 17 August 2009 with the successful first test flight of the Inflatable Re-entry Vehicle Experiment (IRVE). The heat shield had been [[vacuum packing|vacuum-packed]] into a {{convert|15|in|adj=mid|cm|-diameter}} payload shroud and launched on a [[Black Brant (rocket)|Black Brant 9]] [[sounding rocket]] from NASA's Wallops Flight Facility on Wallops Island, Virginia. "Nitrogen inflated the {{convert|10|ft|m|adj=mid|-diameter}} heat shield, made of several layers of [[silicone]]-coated <nowiki>[</nowiki>[[Kevlar]]<nowiki>]</nowiki> fabric, to a mushroom shape in space several minutes after liftoff."<ref name=nasa20090817/> The rocket apogee was at an altitude of {{convert|131|mi}} where it began its descent to supersonic speed. Less than a minute later the shield was released from its cover to inflate at an altitude of {{convert|124|mi}}. The inflation of the shield took less than 90 seconds.<ref name=nasa20090817>[http://www.nasa.gov/topics/aeronautics/features/irve.html NASA Launches New Technology: An Inflatable Heat Shield] {{Webarchive|url=https://web.archive.org/web/20101219090403/http://www.nasa.gov/topics/aeronautics/features/irve.html |date=December 19, 2010 }}, [[NASA]] Mission News, 2009-08-17, accessed 2011-01-02.</ref>

=== NASA HIAD ===
Following the success of the initial IRVE experiments, NASA developed the concept into the more ambitious Hypersonic Inflatable Aerodynamic Decelerator (HIAD). The current design is shaped like a shallow cone, with the structure built up as a stack of circular inflated tubes of gradually increasing major diameter. The forward (convex) face of the cone is covered with a flexible thermal protection system robust enough to withstand the stresses of atmospheric entry (or reentry).<ref name = HughesOverview>{{cite web
 |url          = https://solarsystem.nasa.gov/docs/9.2%20Hughes%20Hypersonic%20Inflatable%20Aerodynamic%20Decelerator%20(HIAD)%20Technology%20Development%20Overview.pdf
 |title        = Hypersonic Inflatable Aerodynamic Decelerator (HIAD) Technology Development Overview
 |last         = Hughes
 |first        = Stephen J.
 |website      = www.nasa.gov
 |publisher    = NASA
 |access-date  = 28 March 2017
 |archive-url  = https://web.archive.org/web/20170126043753/http://solarsystem.nasa.gov/docs/9.2%20Hughes%20Hypersonic%20Inflatable%20Aerodynamic%20Decelerator%20(HIAD)%20Technology%20Development%20Overview.pdf
 |archive-date = 26 January 2017
 |url-status   = dead
}}</ref><ref name = Cheatwood2016>{{cite web
 |url          = https://www.nasa.gov/sites/default/files/atoms/files/gcd_industryday_hiad.pdf
 |title        = Hypersonic Inflatable Aerodynamic Decelerator (HIAD) Technology
 |last         = Cheatwood
 |first        = Neil
 |date         = 29 June 2016
 |website      = www.nasa.gov
 |publisher    = NASA
 |access-date  = 28 March 2017
 |archive-date = February 24, 2017
 |archive-url  = https://web.archive.org/web/20170224080715/https://www.nasa.gov/sites/default/files/atoms/files/gcd_industryday_hiad.pdf
 |url-status   = live
}}</ref>

In 2012, a HIAD was tested as Inflatable Reentry Vehicle Experiment 3 (IRVE-3) using a sub-orbital sounding rocket, and worked.<ref>{{Cite web|url=http://www.ulalaunch.com/uploads/docs/Published_Papers/Supporting_Technologies/LV_Recovery_and_Reuse_AIAASpace_2015.pdf|title=''Launch Vehicle Recovery and Reuse ''|access-date=January 10, 2018|archive-date=July 6, 2016|archive-url=https://web.archive.org/web/20160706013800/http://www.ulalaunch.com/uploads/docs/Published_Papers/Supporting_Technologies/LV_Recovery_and_Reuse_AIAASpace_2015.pdf|url-status=live}}</ref>{{rp|8}}

See also [[Low-Density Supersonic Decelerator]], a NASA project with tests in 2014 and 2015 of a 6 m diameter SIAD-R.

=== LOFTID ===
[[File:LOFTID inflates in space while attached to Centaur upper stage.gif|thumb|LOFTID inflating in orbit]]
A {{convert|6|m|ft|adj=on|sp=us}} inflatable reentry vehicle, ''Low-Earth Orbit Flight Test of an Inflatable Decelerator'' ([[LOFTID]]),<ref>{{Cite news|url=https://spacenews.com/noaa-finalizes-secondary-payload-for-jpss-2-launch/|title=NOAA finalizes secondary payload for JPSS-2 launch|date=March 10, 2020|website=SpaceNews|access-date=March 14, 2020|archive-date=October 1, 2021|archive-url=https://web.archive.org/web/20211001035259/https://spacenews.com/noaa-finalizes-secondary-payload-for-jpss-2-launch/|url-status=live|last1=Foust |first1=Jeff }}</ref> was launched in November 2022, inflated in orbit, reentered faster than Mach 25, and was successfully recovered on November 10.