Editing Lunar Roving Vehicle (section)

== Usage ==

The LRV was used during the lunar surface operations of Apollo 15, 16 and 17, the J missions of the Apollo program.  On each mission, the LRV was used on three separate EVAs, for a total of nine lunar traverses, or sorties.  During operation, the commander (CDR) always drove, while the Lunar Module Pilot (LMP) was a passenger who assisted with navigation.<ref>{{cite web |url=https://www.hq.nasa.gov/alsj/a15/a15.summary.html |title=Apollo 15 Mission Summary: Mountains of the Moon |last=Jones |first=Eric |website=Apollo Lunar Surface Journal }}</ref><ref>{{cite book |title=Lunar Rover: Owner's Workshop Manual |last1=Riley |first1=Christopher |last2=Woods |first2=David |last3=Dolling |first3=Philip |date=December 2012 |publisher=[[Haynes Manual|Haynes]] |isbn=9780857332677 |page=165}}</ref>

{| class="wikitable" style="text-align: center;"
|-
! Mission 
! Total distance
! Total time 
! Longest single traverse
! Maximum range from the [[Apollo Lunar Module|LM]]
|-
| [[Apollo 15]] (LRV-1)
| {{convert|17.25|mi|km|2}}
| 3 h 02 min 
| {{convert|7.75|mi|km|2}}
| {{convert|3.1|mi|km|1}}
|- 
| [[Apollo 16]] (LRV-2)
| {{convert|16.50|mi|km|2}}
| 3 h 26 min
| {{convert|7.20|mi|km|2}} 
| {{convert|2.8|mi|km|1}} 
|-
| [[Apollo 17]] (LRV-3)
| {{convert|22.30|mi|km|2}} 
| 4 h 26 min
| {{convert|12.50|mi|km|2}} 
| {{convert|4.7|mi|km|1}}
|}

An operational constraint on the use of the LRV was that the astronauts must be able to walk back to the LM if the LRV were to fail at any time during the EVA (called the "Walkback Limit"). Thus, the traverses were limited in the distance they could go at the start and at any time later in the EVA. Therefore, they went to the farthest point away from the LM and worked their way back to it so that, as the life support consumables were depleted, their remaining walk back distance was equally diminished. This constraint was relaxed during the longest traverse on Apollo 17, based on the demonstrated reliability of the LRV and spacesuits on previous missions. A paper by Burkhalter and Sharp provides details on usage.<ref>{{cite journal
|title=Lunar Roving Vehicle: Historical Origins, Development and Deployment 
|date=1995
|last1=Burkhalter
|first1=Bettye B
|last2=Sharpe
|first2=Mitchell R
|journal=Journal of the British Interplanetary Society
|volume=48
|issue=5
|pages=199–212}}
</ref>

=== Deployment ===
[[File:Apollo 15 Lunar Roving Vehicle deployment.webm|thumb|LRV extraction timelapse from Apollo 15]]
Astronaut deployment of the Lunar Roving Vehicle from the LM's open Quadrant 1 bay was achieved with a system of pulleys and braked reels using ropes and cloth tapes. The rover was folded and stored in the bay with the underside of the chassis facing out. One astronaut would climb the egress ladder on the LM and release the rover, which would then be slowly tilted out by the second astronaut on the ground through the use of reels and tapes. As the rover was let down from the bay, most of the deployment was automatic. The rear wheels folded out and locked in place. When they touched the ground, the front of the rover could be unfolded, the wheels deployed, and the entire frame let down to the surface by pulleys.<ref>{{Cite web|title=How did they pack the Apollo lunar rover? - collectSPACE: Messages|url=http://www.collectspace.com/ubb/Forum29/HTML/000731.html|access-date=2022-02-15|website=www.collectspace.com}}</ref>

The rover components locked into place upon opening. Cabling, pins, and tripods would then be removed and the seats and footrests raised. After switching on all the electronics, the vehicle was ready to back away from the LM.<ref name="ApolloVehiclesNASA"/>

=== Locations ===
Four flight-ready LRVs were manufactured, as well as several others for testing and training.<ref name="ApolloVehiclesNASA" /> Three were transported to and left on the Moon via the [[Apollo program|Apollo]] 15, 16, and 17 missions (LRV-1 to 3), with the fourth (LRV-4) used for spare parts for the first three following the [[Canceled Apollo missions|cancellation]] of Apollo 18.<ref name="ApolloVehiclesNASA" /><ref>{{Cite web |date=2012-05-06 |title=A Field Guide to American Spacecraft {{!}} LRV #4 |url=http://web.mac.com/jimgerard/AFGAS/pages/rovers/nasmlrv4.html |access-date=2023-05-24 |archive-url=https://web.archive.org/web/20120506033624/http://web.mac.com/jimgerard/AFGAS/pages/rovers/nasmlrv4.html |archive-date=6 May 2012 }}</ref>

The rover used on Apollo 15 was left at [[Hadley–Apennine (Moon)|Hadley-Apennine]] ({{coord|26.10|N|3.65|E|globe:moon|name=Apollo 15 Lunar Roving Vehicle at Hadley–Apennine}}). The rover used on Apollo 16 was left at [[Descartes Highlands|Descartes]] ({{coord|8.99|S|15.51|E|globe:moon|name=Apollo 16 Lunar Roving Vehicle at Descartes Highlands}}). The rover used on Apollo 17 was left at [[Taurus-Littrow]] ({{coord|20.16|N|30.76|E|globe:moon|name=Apollo 17 Lunar Roving Vehicle at Taurus-Littrow}}) and was seen by the [[Lunar Reconnaissance Orbiter]] during passes in 2009 and 2011. In 2020 the State of Washington designated the flown rovers as historic landmarks.<ref name="SoWRoverGW">{{cite web |url=https://www.geekwire.com/2020/resting-places-boeing-built-moon-rovers-win-washington-state-landmark-status/#:~:text=NASA%27s%20Boeing%2Dbuilt%20moon%20rovers%20are%20granted%20Washington%20state%20landmark%20status&text=Three%20hot%20rods%20on%20the,vote%20by%20a%20state%20commission. |title=NASA's Boeing-built moon rovers are granted Washington state landmark status |publisher=[[GeekWire]] |date=24 October 2020 |access-date=12 May 2021}}</ref><ref name="SoWRoverLandmark">{{cite web |url=https://wisaard.dahp.wa.gov/Search/1162/Detail/6036 |title=Washington Heritage Register |publisher=[[State of Washington]] |date=23 October 2020 |access-date=12 May 2021}}</ref>

Since only the upper stages of the lunar excursion modules could return to lunar orbit from the surface, the vehicles, along with the lower stages were abandoned. As a result, the only lunar rovers on display are LRV-4, test vehicles, trainers, and mock-ups.<ref name="ApolloVehiclesNASA" />
* Lunar Roving Vehicle 4 (LRV-4)[https://commons.wikimedia.org/wiki/Category:Lunar_Roving_Vehicle_4_at_the_Kennedy_Space_Center_Visitor_Complex] is on display at the [[Kennedy Space Center Visitors Complex]] in [[Cape Canaveral, Florida]].
* The Engineering Mockup [https://commons.wikimedia.org/wiki/Category:Lunar_Roving_Vehicle_at_The_Museum_of_Flight], intended to design and integrate subsystems,<ref name="ApolloVehiclesNASA" /> is on display at the [[Museum of Flight]] in [[Seattle, Washington]].<ref>{{Cite web |date=2012-05-06 |title=A Field Guide to American Spacecraft {{!}} LRV |url=http://web.mac.com/jimgerard/AFGAS/pages/rovers/moflrv.html |access-date=2023-05-24 |archive-url=https://web.archive.org/web/20120506030945/http://web.mac.com/jimgerard/AFGAS/pages/rovers/moflrv.html |archive-date=6 May 2012 }}</ref>
* The Qualification Test Unit [https://commons.wikimedia.org/wiki/Category:Lunar_Roving_Vehicle_at_the_National_Air_and_Space_Museum], designed to study integration of all LRV subsystems,<ref name="ApolloVehiclesNASA" /> is on display at the [[National Air and Space Museum]] in [[Washington, D.C.]]<ref>{{Cite web |date=2012-05-06 |title=A Field Guide to American Spacecraft {{!}} LRV |url=http://web.mac.com/jimgerard/AFGAS/pages/rovers/nasmlrv.html |access-date=2023-05-24 |archive-url=https://web.archive.org/web/20120506033621/http://web.mac.com/jimgerard/AFGAS/pages/rovers/nasmlrv.html |archive-date=6 May 2012 }}</ref> 
* The Vibration Test Unit [https://commons.wikimedia.org/wiki/Category:Lunar_Roving_Vehicle_at_the_U.S._Space_%26_Rocket_Center], intended to study durability and handling of launch stresses,<ref name="ApolloVehiclesNASA" /> is on display in the Davidson Saturn V Center at the [[U.S. Space & Rocket Center]] in [[Huntsville, Alabama]].<ref>{{Cite web |date=2012-05-06 |title=A Field Guide to American Spacecraft {{!}} LRV |url=http://web.mac.com/jimgerard/AFGAS/pages/rovers/ussrclrv2.html |access-date=2023-05-24 |archive-url=https://web.archive.org/web/20120506031000/http://web.mac.com/jimgerard/AFGAS/pages/rovers/ussrclrv2.html |archive-date=6 May 2012 }}</ref><ref>{{Cite web |title=Lunar Roving Vehicle, Vibration Test Unit {{!}} National Air and Space Museum |url=https://airandspace.si.edu/collection-objects/lunar-roving-vehicle-vibration-test-unit/nasm_A19750837000 |access-date=2023-05-24 |website=airandspace.si.edu |language=en}}</ref>
* The 1-gravity trainer [https://commons.wikimedia.org/wiki/Category:Lunar_Roving_Vehicle_at_Space_Center_Houston] is on display at the [[Johnson Space Center]] in [[Houston, Texas]].<ref>{{Cite web |date=2012-05-06 |title=A Field Guide to American Spacecraft {{!}} LRV |url=http://web.mac.com/jimgerard/AFGAS/pages/rovers/schlrv.html |access-date=2023-05-24 |archive-url=https://web.archive.org/web/20120506030955/http://web.mac.com/jimgerard/AFGAS/pages/rovers/schlrv.html |archive-date=6 May 2012 }}</ref>

As mentioned before, additional test units were built, like a static model, two 1/6 gravity models, a mass model.<ref name="ApolloVehiclesNASA" /><gallery mode="packed" caption="Lunar Roving Vehicles, test vehicles and trainers">
File:Apollo 15- Follow the Tracks (6816337786).jpg|[[Lunar Reconnaissance Orbiter|LRO]] image of [[Apollo 15]] site, '''LRV-1''' is near the right edge
File:Apollo 16 LS.png|[[Lunar Reconnaissance Orbiter|LRO]] image of [[Apollo 16]] site, '''LRV-2''' is near the right edge
File:Apollo 17 landing site, labeled.jpg|[[Lunar Reconnaissance Orbiter|LRO]] image of [[Apollo 17]] site, '''LRV-3''' is in the lower right
File:Lunar Roving Vehicle no. 4, Boeing, 1971 - Kennedy Space Center - Cape Canaveral, Florida - DSC02871.jpg|'''LRV-4''', [[Kennedy Space Center Visitors Complex|KSC Visitors Complex]]
File:Space Center Houston March 2022 10 (Lunar Roving Vehicle trainer).jpg|'''LRV''' '''1-gravity trainer''', [[Space Center Houston]]
File:Seattle (9287877759).jpg|'''LRV''' '''engineering mockup''', [[Museum of Flight]]
File:MSFC 76545 on display.JPG|'''LRV''' '''Vibration Test Unit''', [[U.S. Space & Rocket Center]]
File:Lunar Roving Vehicle at SNASM.jpg|'''LRV''' '''Qualification Test Unit''', [[National Air and Space Museum]]</gallery>
[[Replica]]s of rovers are on display at the [[Johnson Space Center]] in [[Houston, Texas]], the [[Kennedy Space Center Visitors Complex]] in [[Cape Canaveral, Florida]], the [[National Museum of Naval Aviation]] in [[Pensacola, Florida]], the [[Evergreen Aviation & Space Museum]] in [[McMinnville, Oregon]], the [[Kansas Cosmosphere and Space Center]] in [[Hutchinson, Kansas]], and the [[Omega Museum]] in [[Biel, Switzerland]].<ref name="fieldguide">{{cite web |title=Lunar Roving Vehicles |url=http://web.mac.com/jimgerard/AFGAS/pages/rovers/index.html |url-status=dead |archive-url=https://web.archive.org/web/20110808161124/http://web.mac.com/jimgerard/AFGAS/pages/rovers/index.html |archive-date=8 August 2011 |access-date=24 August 2009 |work=Field Guide to American Spacecraft}}</ref> A replica on loan from the Smithsonian Institution is on display at the [[Mission: Space]] attraction at [[Epcot]] at the [[Walt Disney World Resort]] near [[Orlando, Florida]].<ref name="fieldguide" /><ref name="spinoff 2003">{{cite news |url=http://www.sti.nasa.gov/tto/spinoff2003/ch_2.html |archive-url=https://web.archive.org/web/20031022174556/http://www.sti.nasa.gov/tto/spinoff2003/ch_2.html |url-status=dead |archive-date=2003-10-22 |title=Blast-Off on Mission: SPACE |date=2003 |work=Science and Technical Information, Spinoff |publisher=NASA |access-date=24 August 2009}}</ref>