View source for Crawler-transporter

{{short description|NASA rocket transport vehicle}}
{{Use American English|date=January 2014}}
{{Infobox automobile
| name = Crawler-transporter
| image = Crawler-Transporter.jpg
| image_size = 275px
| caption =
| aka = Missile Crawler Transporter Facilities
| manufacturer = [[Marion Power Shovel Company]]
| model_years = 1965
| engine = {{ubli
 | 2 × {{convert|2750|hp|kW|abbr=on|lk=on|order=flip}} V16 [[ALCO 251|ALCO 251C]] [[diesel engine]]s, driving 4 × {{convert|1341|hp|kW|abbr=on|order=flip}} generators for traction
 | 2 × {{convert|1065|hp|kW|abbr=on|order=flip}} engines driving 2 × {{convert|1006|hp|kW|abbr=on|order=flip}} generators powering auxiliaries: jacking, steering, lighting, and ventilating.
 }}
| transmission = 16 × traction motors, 4 per corner
| length = {{convert|131|ft|m|0|abbr=on|order=flip}}
| width = {{convert|114|ft|m|0|abbr=on|order=flip}}
| height = Adjustable, {{convert|20|to|26|ft|m|0|abbr=on|order=flip}}
| weight = {{convert|2721|tonne|lb|abbr=on|sigfig=3}}<ref name="NASAsci"/>
| sp = us
| module =
 {{Infobox NRHP
 | embed = yes
 | name = Missile Crawler Transporter Facilities
 | nrhp_type = nrhp
 | location = [[Kennedy Space Center]], [[Florida]]
 | added = January 21, 2000
 | refnum = 99001643<ref name="nris" />
 | mpsub = [[John F. Kennedy Space Center MPS]]
 }}
}}
The '''crawler-transporters''', formally known as the '''Missile Crawler Transporter Facilities''',<ref name="nris" /> are a pair of [[continuous track|tracked]] [[vehicle]]s used to transport [[Launch vehicle|launch vehicles]] from [[NASA]]'s [[Vehicle Assembly Building]] (VAB) along the [[Crawlerway]] to [[Kennedy Space Center Launch Complex 39|Launch Complex 39]].  They were originally used to transport the [[Saturn IB]] and [[Saturn V]] [[rocket]]s during the [[Apollo program|Apollo]], [[Skylab]] and [[Apollo–Soyuz]] programs. They were then used to transport [[Space Shuttle]]s from 1981 to 2011. The crawler-transporters carry vehicles on the [[mobile launcher platform]]s (MLPs) used by NASA, and after each launch return to the pad to take the platform back to the VAB.<ref name="hostares" />

The two crawler-transporters were designed and built by [[Marion Power Shovel Company]] using some components designed and built by [[Rockwell International]] at a cost of {{USD|14 million}} ({{USD|128.5 million}} in 2022) each.<ref name="transport20120905" /> Upon its construction, the crawler-transporter became the largest self-powered land vehicle in the world until it was beaten in 2013 with the production of the ultraheavy [[XGC88000 crawler crane]]. While other vehicles such as [[bucket-wheel excavator]]s like [[Bagger 288]], [[dragline excavator]]s like [[Big Muskie]] and [[power shovel]]s like [[Marion 6360|The Captain]] are significantly larger, they are powered by external sources.

The two crawler-transporters were added to the National Register of Historic Places on January 21, 2000.<ref name="nris" />

==Specifications==
[[File:Crawler-transporter cutaway view.gif|thumb|left|Diagram of a crawler-transporter]]

The crawler-transporter has a mass of {{convert|2721|tonne|e6lb ST|0|abbr=off}} and has eight tracks, two on each corner.<ref name="NASAsci" /> Each track has 57 shoes, and each shoe weighs {{convert|1984|lb|kg|abbr=on|order=flip}}. The vehicle measures {{convert|131|by|114|ft|m|order=flip|sp=us}}. The height from ground level to the platform is adjustable from {{convert|20|to|26|ft|m|abbr=on|order=flip}}, and each side can be raised and lowered independently of the other. The crawler uses a laser guidance system and a leveling system to keep the [[Mobile Launcher Platform]] level within 10 [[minutes of arc]] (0.16 degrees; about {{convert|1|ft|cm|abbr=on|order=flip}} at the top of the Saturn V), while moving up the 5 percent grade to the launch site.<ref name="KSC-05PD-1322" /> A separate laser docking system provides pinpoint accuracy when the crawler-transporter and Mobile Launch Platform are positioned in the VAB or at the launch pad.<ref name="KSCpao" /> A team of nearly 30 engineers, technicians and drivers operate the vehicle, centered on an internal control room, and the crawler is driven from two control cabs located at either end.<ref name="spotlight" /><ref name="bbc20190626" /> Before the launch the crawler-transporter is removed.<!--seems so, just have a look at File:Shuttle Discovery July 25 pre-launch.jpg left side-->

The crawlers were overhauled in 2003 with upgrades to the Motor Control Center, which houses the switchgear and electrical controls of all of major systems on board; a new engine and pump ventilation system; new diesel engine radiators; and replacement of the two driver cabs on each vehicle (one on each end).<ref name="spotlight" /> After the 2003 refit, each crawler had 16 traction motors, powered by four {{convert|1341|hp|kW|abbr=on|order=flip}} generators, in turn driven by two {{convert|2750|hp|kW|abbr=on|order=flip}} V16 [[ALCO 251|ALCO 251C]] [[diesel engine]]s. Two {{convert|1006|hp|kW|abbr=on|order=flip}} generators, driven by two {{convert|1065|hp|kW|abbr=on|order=flip}} engines, were used for jacking, steering, lighting, and ventilating. Two {{convert|201|hp|kW|abbr=on|order=flip}} generators were also available to power the Mobile Launcher Platform. The crawler's tanks held {{convert|5000|USgal|L|sp=us|order=flip}} of diesel fuel, and it burned {{convert|125.7|USgal/mi|L/km|sp=us|order=flip}}.<ref name ="NASAsci" /> 

Due to their age and the need to support the heavier [[Space Launch System]] and its launch tower, in 2012–2014 the crawlers were undergoing an upgrade involving "new engines, new exhausts, new brakes, new hydraulics, new computers"; CT-2 was further upgraded in 2014–2016 to increase its lifting capacity from {{convert|12|to|18|e6lb|t|abbr=off|order=flip}}.<ref name="transport20120905" /><ref name="NSF-2012-11" /><ref name=CT-2_upgrade/>

The crawlers traveled along the {{convert|5535|and|6828|m|km mi|1|abbr=on|order=out}} Crawlerways, to [[LC-39A]] and [[LC-39B]], respectively, at a maximum speed of {{convert|1|mph|km/h|order=flip|sp=us}} loaded, or {{convert|2|mph|km/h|order=flip|abbr=on}} unloaded.<ref name="bbc20190626" /><ref name="NASA-cways" /> The average trip time from the VAB along the Crawlerway to Launch Complex 39 is about five hours.<ref name="NASAsci" />  Each Crawlerway is {{Convert|7|ft|m|0|abbr=on|order=flip}} deep and covered with Alabama and Tennessee river rock for its low friction properties to reduce the possibility of sparks. In 2000, NASA unearthed and restored an Apollo-era segment of the Crawlerway to provide access to High Bay 2 in the VAB in order to provide protection from a hurricane for up to three Shuttles at the same time.<ref name="space20000813" />

Kennedy Space Center has been using the same two crawlers since their initial delivery in 1965. They are now nicknamed "[[Hans and Franz]]", after the parodic Austrian body-builder characters on ''[[Saturday Night Live]]'', played by [[Dana Carvey]] and [[Kevin Nealon]].<ref name="diesel-power" /> In their lifetime, they have traveled more than {{convert|3400|mi|km|abbr=on|order=flip}}, about the same driving distance as from [[Miami]] to [[Seattle]].<ref name="spotlight" />

==Future use==
===Crawler-Transporter 2===
NASA currently uses crawler-transporter 2 to transport the [[Space Launch System]] with the [[Orion (spacecraft)|Orion spacecraft]] atop it from the [[Vehicle Assembly Building]] to [[Kennedy Space Center Launch Complex 39B|Launch Pad 39B]] for the [[Artemis program|Artemis missions]]. Early in 2016, NASA finished upgrading crawler-transporter 2 (CT-2) to a "Super Crawler" for use in the [[Artemis program]].<ref name="CT-2_upgrade" /> NASA performed a rollout of the [[Artemis 1]] Space Launch System and Orion on March 17, 2022 for the first Wet Dress Rehearsal, and the rollout for launch, which launched in November 2022. The rollout for the WDR, marked the first time one of the crawler transporters rolled a launch vehicle to the launch pad since [[STS-135]].<ref name="spacecom-2022025" />

===Crawler-Transporter 1===
NASA had originally planned for crawler-transporter 1 to be used by commercial launch vehicles.<ref name="NASA-crawler-50" /> In April 2016, then Orbital ATK, now [[Northrop Grumman Innovation Systems]], and NASA entered negotiations for the lease of CT-1 and one of the four Vehicle Assembly Building bays.<ref name="florida-atk-picked-vab" /> Northrop Grumman planned to use CT-1 to transport their [[OmegA]] from the Vehicle Assembly Building to [[Kennedy Space Center Launch Complex 39B|Launch Pad 39B]]. OmegA was cancelled in September of 2020 after Northrop Grumman lost the [[National Security Space Launch]] contract to [[United Launch Alliance]] and [[SpaceX]].<ref name="spacenews-omega" />

==Appearances in popular culture==
The crawler-transporters have featured in television and movies. In a 2007 [[List of Dirty Jobs episodes#ep59|season three episode]] of ''[[Dirty Jobs]]'', host [[Mike Rowe]] helps workers maintain a crawler-transporter and takes the vehicle for a short drive.<ref name="discovery2007" /> The crawler was also seen in the 1995 film ''[[Apollo 13 (film)|Apollo 13]]'', the 2011 film ''[[Transformers: Dark of the Moon]]'' and the 2019 film ''[[Apollo 11 (2019 film)|Apollo 11]]''. Similar vehicles also appeared in the 2013 film ''[[Pacific Rim (film)|Pacific Rim]]''.

In the 2009 ''[[Fallout 3]]'' video game add-on pack "[[Broken Steel]]", the US government survivors, The Enclave, have a mobile base built on and into a heavily modified crawler. In ''[[Sid Meier's Alpha Centauri]]'', various units are called "crawlers" and feature chassis based on the crawler-transporters. In ''[[Asphalt 8: Airborne]]'', three crawler-transporters drive over the space center French Guiana track.

==Gallery==
<gallery class="center" mode="packed">
File:LC-39 Observation gantry pano.jpg|Crawlerway junction at the LC-39 observation gantry. The right track leads to pad LC-39A (pictured with {{OV|Endeavour}}), while the left track leads to pad LC-39B.
</gallery>
<gallery class="center" heights="160px" mode="packed">
File:Ap11-KSC-69PC-241HR.jpg|Saturn V, [[service structure]] and MLP on top of a crawler
File:Crawlertreds.jpg|Detail of crawler treads
File:STS-79 rollout.jpg|{{OV|Atlantis}} (STS-79) atop an [[Mobile launcher platform|MLP]] (and crawler beneath)
File:STS-114 rollout.jpg|A crawler-transporter carrying {{OV|Discovery|full=no}} (STS-114) travels the ramp to [[Kennedy Space Center Launch Complex 39|Launch Pad 39B]]. The vehicle's back end can be raised, keeping the Shuttle and the MLP level.
File:STS-51-L - Space Shuttle Challenger on the Crawler-Transporter.jpg|{{OV|Challenger}} atop an MLP atop a crawler, in transit to its launch pad prior to [[Space Shuttle Challenger disaster|its final flight]] ([[STS-51-L]]), January 28, 1986
File:Ares I-X rollout on mobile launch platform.jpg|Crawler carrying the [[Ares I-X]] atop an MLP
</gallery>

== See also ==
* [[List of largest machines]]

==References==
{{Reflist|refs=
<ref name="bbc20190626">{{Cite news |url=https://www.bbc.com/future/article/20190626-apollo-in-50-numbers-the-rocket |title=Apollo in 50 numbers: The rocket |publisher=BBC |last=Hollingham |first=Richard |date=June 26, 2019 |access-date=June 27, 2019 |archive-url=https://web.archive.org/web/20220317071533/https://www.bbc.com/future/article/20190626-apollo-in-50-numbers-the-rocket |archive-date=2022-03-17 |url-status=live }}</ref>

<ref name="CT-2_upgrade">{{cite news |url=https://www.nasaspaceflight.com/2016/02/ct-2-completes-super-crawler-modifications-sls/ |title=CT-2 completes Super Crawler modifications for SLS program |work=NASA Spaceflight |first1=Chris |last1=Gebhardt |first2=Chris |last2=Bergin |date=February 23, 2016 |access-date=June 24, 2016 |archive-url=https://web.archive.org/web/20160430040515/https://www.nasaspaceflight.com/2016/02/ct-2-completes-super-crawler-modifications-sls/ |archive-date=April 30, 2016 |url-status=live }}</ref>

<ref name="discovery2007">{{cite web |url=http://dsc.discovery.com/fansites/dirtyjobs/episode/episode-tab-04.html |title=The Complete Dirty Jobs Show Guide: 2007 |work=[[Discovery.com]] |archive-url=https://web.archive.org/web/20121012074054/http://dsc.discovery.com/fansites/dirtyjobs/episode/episode-tab-04.html |archive-date=October 12, 2012 |url-status=dead }}</ref>

<ref name="diesel-power">{{cite magazine |url=https://www.motortrend.com/reviews/0705dp-nasa-diesel-shuttle-crawler/ |title=NASA Diesel-Powered Shuttle Hauler - The Crawlers |magazine=MotorTrend |first=Jason |last=Sands |date=May 17, 2007 |access-date=April 1, 2013 |archive-url=https://web.archive.org/web/20220313044846/https://www.motortrend.com/reviews/0705dp-nasa-diesel-shuttle-crawler/ |archive-date=March 13, 2022 |url-status=live }}</ref>

<ref name="florida-atk-picked-vab">{{cite news |url=https://floridapolitics.com/archives/207644-orbital-atk-picked-use-nasas-vehicle-assembly-building-kennedy-space-center/ |title=Orbital ATK picked to use NASA's Vehicle Assembly Building at Kennedy Space Center |work=Florida Politics |first=Scott |last=Powers |date=April 21, 2016 |access-date=June 24, 2016 |archive-url=https://web.archive.org/web/20160803223152/http://floridapolitics.com/archives/207644-orbital-atk-picked-use-nasas-vehicle-assembly-building-kennedy-space-center |archive-date=August 3, 2016 |url-status=live}}</ref>

<ref name="hostares">{{cite web |url=https://www.nasa.gov/mission_pages/constellation/main/Constellationfacilities.html |title=Kennedy Prepares to Host Constellation |publisher=NASA |date=September 28, 2007 |access-date=June 7, 2009 |archive-url=https://web.archive.org/web/20220314175158/https://www.nasa.gov/mission_pages/constellation/main/Constellationfacilities.html |archive-date=March 14, 2022 |url-status=live |last1=Siceloff |first1=Steven }}</ref>

<ref name="KSC-05PD-1322">{{cite web |url=http://mediaarchive.ksc.nasa.gov/detail.cfm?mediaid=26125 |title=KSC-05PD-1322 |publisher=NASA |date=June 15, 2005 |access-date=June 18, 2007 |archive-url=https://web.archive.org/web/20080109035956/http://mediaarchive.ksc.nasa.gov/detail.cfm?mediaid=26125 |archive-date=January 9, 2008 |url-status=dead}}</ref>

<ref name="KSCpao">{{cite web |url=http://www-pao.ksc.nasa.gov/nasafact/count3teaf.htm |title=Countdown! NASA Launch Vehicles and Facilities |publisher=NASA |id=PMS 018-B |date=October 1991 |access-date=June 18, 2007 |url-status=dead |archive-url=https://web.archive.org/web/20080109045657/http://www-pao.ksc.nasa.gov/nasafact/count3teaf.htm |archive-date=January 9, 2008}}</ref>

<ref name="NASA-crawler-50">{{cite news |url=https://www.nasa.gov/content/nasas-giant-crawlers-turn-50-years-old-pivot-toward-future-exploration |title=NASA's Giant Crawlers turn 50 Years Old, Pivot Toward Future Exploration |publisher=NASA |first=Linda |last=Herridge |date=February 22, 2015 |access-date=June 24, 2016 |archive-url=https://web.archive.org/web/20160620110128/http://www.nasa.gov/content/nasas-giant-crawlers-turn-50-years-old-pivot-toward-future-exploration/ |archive-date=June 20, 2016 |url-status=live }}</ref>

<ref name="NASA-cways">{{cite web |url=https://science.ksc.nasa.gov/facilities/crawlerway.html |title=Crawlerway to the Pad |publisher=NASA |date=October 6, 1993 |access-date=July 16, 2019 |archive-url=https://web.archive.org/web/20220106145248/https://science.ksc.nasa.gov/facilities/crawlerway.html |archive-date=January 6, 2022 |url-status=dead }}</ref>

<ref name="NASAsci">{{cite web |url=https://science.ksc.nasa.gov/facilities/crawler.html |title=Crawler-Transporter |publisher=NASA |date=April 21, 2003 |access-date=June 18, 2020 |archive-url=https://web.archive.org/web/20200601012639/https://science.ksc.nasa.gov/facilities/crawler.html |archive-date=June 1, 2020 |url-status=dead}}</ref>

<ref name="nris">{{NRHP Focus|99001643}}</ref>

<ref name="NSF-2012-11">{{cite news |last1=Bergin |first1=Chris |title=All hail the Super Crawler – CT-2 put through its paces ahead of SLS |url=https://www.nasaspaceflight.com/2012/11/super-crawler-ct-2-through-paces-ahead-sls/ |work=NASASpaceflight.com |date=November 24, 2012 |archive-url=https://web.archive.org/web/20220418112733/https://www.nasaspaceflight.com/2012/11/super-crawler-ct-2-through-paces-ahead-sls/ |archive-date=April 18, 2022 |url-status=live }}</ref>

<ref name="space20000813">{{cite web |url=http://www.space.com/news/spaceshuttles/shuttle_safehaven_000812.html |title=Shuttle Safe Haven Opens at Kennedy Space Center |work=Space.com |last=Halvorson |first=Todd |date=August 13, 2000 |archive-url=https://web.archive.org/web/20050920102345/http://www.space.com/news/spaceshuttles/shuttle_safehaven_000812.html |archive-date=September 20, 2005 |url-status=dead }}</ref>

<ref name="spacecom-2022025">{{cite news|last=Wall|first=Mike|url=https://www.space.com/nasa-artemis-1-moon-mission-launch-may-2022 |title=NASA's Artemis 1 moon mission, 1st flight of new megarocket, won't launch until May |publisher=Space.com|date=25 February 2022|access-date=25 February 2022 |archive-url=https://web.archive.org/web/20220408221953/https://www.space.com/nasa-artemis-1-moon-mission-launch-may-2022 |archive-date=April 8, 2022 |url-status=live }}</ref>

<ref name="spacenews-omega">{{cite news|last=Sandra|first=Erwin|url=https://spacenews.com/northrop-grumman-to-terminate-omega-rocket-program/|title=Northrop Grumman to terminate OmegA rocket program|publisher=SpaceNews|date=9 September 2020|access-date=11 February 2022}}</ref>

<ref name="spotlight">{{cite journal |url=http://sfa.nasa.gov/MISSIONPOSTERS/spotlight/spotlightCrawler.pdf |title=Crawler Transporter |journal=Return to Flight Spotlight |publisher=NASA |issue=1 |date=April 2004 |archive-url=https://web.archive.org/web/20090320065927/http://sfa.nasa.gov/MISSIONPOSTERS/spotlight/spotlightCrawler.pdf |archive-date=March 20, 2009 |url-status=dead }}</ref>

<ref name="transport20120905">{{cite web |url=https://www.wnyc.org/story/284187-nasas-big-rig-and-we-mean-really-big-gets-a-tune-up-pics/ |title=NASA's Historic Giant Crawler Gets a Tune Up for Modern Times (Pics) |work=Transportation Nation |first=Matthew |last=Peddie |date=September 5, 2012 |url-status=live |archive-url=https://web.archive.org/web/20220418113531/https://www.wnyc.org/story/284187-nasas-big-rig-and-we-mean-really-big-gets-a-tune-up-pics/ |archive-date=April 18, 2022 }}</ref>

}}

==External links==
{{Commons category|Crawler-transporters}}
* {{Coord|28.58808|-80.65521|region:US-FL_type:landmark_scale:3000}} - Crawler-transporter parking area at Kennedy Space Center

{{Kennedy Space Center}}
{{NASA centers}}
{{Apollo program}}
{{Apollo program hardware}}
{{Skylab}}
{{Space Shuttle}}
{{Project Constellation}}
{{Artemis program}}

{{DEFAULTSORT:Crawler-Transporter}}
[[Category:Apollo program hardware]]
[[Category:Kennedy Space Center]]
[[Category:Marion Power Shovel Company]]
[[Category:NASA vehicles]]
[[Category:National Register of Historic Places in Brevard County, Florida]]
[[Category:Space Shuttle program]]
[[Category:Tracked vehicles]]
[[Category:Vehicles introduced in 1965]]