Splashdown Explained
Splashdown is the method of landing a spacecraft in a body of water, usually by parachute. The method has been used primarily by American crewed capsules including NASA’s Mercury, Gemini, Apollo and Orion along with the private SpaceX Dragon. It is also possible for the Russian Soyuz and the Chinese Shenzhou crewed capsules to land in water, though this is only a contingency.
As the name suggests, the capsule parachutes into an ocean or other large body of water. The properties of water cushion the spacecraft enough that there is no need for a braking rocket to slow the final descent as is the case with Russian and Chinese crewed space capsules or airbags as is the case with the Boeing Starliner crewed space capsule.
The American practice came in part because American launch sites are on the coastline and launch primarily over water.[1] Russian launch sites are far inland and most early launch aborts were likely to descend on land.
Missions
The splashdown method of landing was used for Mercury, Gemini and Apollo (including Skylab, which used Apollo capsules). Soyuz 23 unintentionally landed on a freezing lake with slushy patches of ice during a snowstorm.[2] [3]
On early Mercury flights, a helicopter attached a cable to the capsule, lifted it from the water and delivered it to a nearby ship. This was changed after the sinking of Liberty Bell 7. All later Mercury, Gemini and Apollo capsules had a flotation collar (similar to a rubber life raft) attached to the spacecraft to increase their buoyancy. The spacecraft would then be brought alongside a ship and lifted onto deck by crane.
After the flotation collar is attached, a hatch on the spacecraft is usually opened. At that time, some astronauts decide to be hoisted aboard a helicopter for a ride to the recovery ship and some decided to stay with the spacecraft and be lifted aboard ship via crane. All Gemini and Apollo flights (Apollos 7 to 17) used the former, while Mercury missions from Mercury 6 to Mercury 9, as well as all Skylab missions and Apollo-Soyuz used the latter, especially the Skylab flights as to preserve all medical data. During the Gemini and Apollo programs, NASA used for the astronauts to practice water egress.
Apollo 11 was America's first Moon landing mission and marked the first time that humans walked on the surface of another planetary body. The possibility of the astronauts bringing "Moon germs" back to Earth was remote, but not impossible. To contain any possible contaminants at the scene of the splashdown, the astronauts donned special Biological Isolation Garments and the outside of the suits were scrubbed prior to the astronauts being hoisted aboard and escorted safely inside a Mobile Quarantine Facility.[4] Both the SpaceX Dragon 1 and Dragon 2 capsules were designed to use the splashdown method of landing. The original cargo Dragon splashed down in the Pacific Ocean off the coast of Baja California. At the request of NASA, both the crew and cargo variations of the Dragon 2 capsule splashes down off the coast of Florida, either in the Atlantic Ocean or the Gulf of Mexico.[5] [6]
The early design concept for the Orion Spacecraft (then known as the Crew Exploration Vehicle) featured recovery on land using a combination of parachutes and airbags, although it was also designed to make a contingency splashdown (only for an in-flight abort) if needed. Due to weight considerations, the airbag design concept was dropped. The present design concept features landings via splashdown in the Pacific Ocean off the coast of California.[7]
Disadvantages
The most dangerous aspect is the possibility of the spacecraft flooding and sinking. For example, when the hatch of Gus Grissom's Liberty Bell 7 capsule blew prematurely, the capsule sank and Grissom almost drowned.
Since the spacecraft's flooding will occur from a location in its hull where it ruptures first, it is important to determine the location on the hull that experiences the highest loading.[8] This location along the impacting side is determined by the surrounding `air cushion' layer, which deforms the water surface before the moment of impact, and results in a non-trivial geometry of the liquid surface during first touch-down.[9] [10] [11]
If the capsule comes down far from any recovery forces, the crew are exposed to greater danger. As an example, Scott Carpenter in Aurora 7 overshot the assigned landing zone by 400km (200miles). These recovery operation mishaps can be mitigated by placing several vessels on standby in several different locations, but this is quite an expensive option.
Locations
Crewed spacecraft
| Spacecraft | Agency | Landing date | Coordinates | Recovery ship | Miss distance (km) | Reference |
|---|
| 1 | Freedom 7 | NASA | May 5, 1961 | 27.2283°N -128°W | | 5.6km (03.5miles) | [12] |
| 2 | Liberty Bell 7 | NASA | July 21, 1961 | 27.5333°N -119°W | | 9.3km (05.8miles) | [13] |
| 3 | Friendship 7 | NASA | February 20, 1962 | 21.4333°N -109°W |
(USS Randolph**) | 74 | [14] |
| 4 | Aurora 7 | NASA | May 24, 1962 | 19.45°N -122°W |
(**) | 400 | [15] |
| 5 | Sigma 7 | NASA | October 3, 1962 | 32.1°N -202°W | | 7.4 | [16] |
| 6 | Faith 7 | NASA | May 16, 1963 | 27.3333°N -202°W | USS Kearsarge | 8.1 | [17] |
| 7 | Gemini 3 | NASA | March 23, 1965 | 22.4333°N -121°W | USS Intrepid | 111 | [18] |
| 8 | Gemini 4 | NASA | June 7, 1965 | 27.7333°N -85°W | | 81 | [19] |
| 9 | Gemini 5 | NASA | August 29, 1965 | 29.7333°N -114°W | USS Lake Champlain | 270 | [20] |
| 10 | Gemini 7 | NASA | December 18, 1965 | 25.4167°N -77°W | USS Wasp | 12 | [21] |
| 11 | Gemini 6A | NASA | December 16, 1965 | 23.5833°N -117°W | USS Wasp | 13 | [22] |
| 12 | Gemini 8 | NASA | March 17, 1966 | 25.2333°N 136°W |
(**) | 2 | [23] |
| 13 | Gemini 9A | NASA | June 6, 1966 | 27.8667°N -75°W | USS Wasp | 0.7 | [24] |
| 14 | Gemini 10 | NASA | July 21, 1966 | 26.75°N -128°W | | 6 | [25] |
| 15 | Gemini 11 | NASA | September 15, 1966 | 24.25°N -70°W | | 5 | [26] |
| 16 | Gemini 12 | NASA | November 15, 1966 | 24.5833°N -126°W | USS Wasp | 5 | [27] |
| 17 | Apollo 7 | NASA | October 22, 1968 | 27.5333°N -68°W | | 3 | [28] |
| 18 | Apollo 8 | NASA | December 27, 1968 | 8.125°N -166.2°W | | 2 | [29] |
| 19 | Apollo 9 | NASA | March 13, 1969 | 23.25°N -123°W | USS Guadalcanal | 5 | [30] [31] |
| 20 | Apollo 10 | NASA | May 26, 1969 | -15.0333°N -203°W | | 2.4 | [32] [33] |
| 21 | Apollo 11 | NASA | July 24, 1969 | 13.3167°N -178°W | | 3.13 | [34] [35] |
| 22 | Apollo 12 | NASA | November 24, 1969 | -15.7833°N -174°W | USS Hornet | 3.7 | [36] [37] |
| 23 | Apollo 13 | NASA | April 17, 1970 | -21.6333°N -187°W | | 1.85 | [38] [39] |
| 24 | Apollo 14 | NASA | February 9, 1971 | -27.0167°N -211°W | | 1.1 | [40] [41] |
| 25 | Apollo 15 | NASA | August 7, 1971 | 26.1167°N -166°W | | 1.85 | [42] [43] |
| 26 | Apollo 16 | NASA | April 27, 1972 | -0.7167°N -169°W | | 0.55 | [44] [45] |
| 27 | Apollo 17 | NASA | December 19, 1972 | -17.8833°N -173°W | USS Ticonderoga | 1.85 | [46] [47] |
| 28 | Skylab 2 | NASA | June 22, 1973 | 24.75°N -129°W | USS Ticonderoga | | [48] |
| 29 | Skylab 3 | NASA | September 25, 1973 | 30.7833°N -149°W | USS New Orleans | | [49] |
| 30 | Skylab 4 | NASA | February 8, 1974 | 31.3°N -167°W | USS New Orleans | | |
| 31 | Apollo CSM-111 | NASA | July 24, 1975 | 22°N -163°W | USS New Orleans | 1.3 | [50] [51] |
| 32 | Soyuz 23 | USSR | October 16, 1976 | Lake Tengiz | Mi-8 helicopter | | [52] |
| 33 | Crew Dragon Demo-2 | SpaceX | August 2, 2020 | 29.8°N -117°W | GO Navigator | | [53] |
| 33 | Crew Dragon Crew-1 | SpaceX | May 2, 2021 | 29.5333°N -97°W | GO Navigator | | [54] |
| 34 | Inspiration4 | SpaceX | September 18, 2021 | | GO Searcher | | [55] |
| 35 | Crew Dragon Crew-2 | SpaceX | November 7, 2021 | | GO Navigator | | |
| 35 | Axiom Mission 1 | SpaceX | April 25, 2022 | | Megan | | |
| 36 | Crew Dragon Crew-3 | SpaceX | May 6, 2022 | | Shannon | | [56] |
| 37 | Crew Dragon Crew-4 | SpaceX | October 14, 2022 | | Megan | | |
| 38 | Crew Dragon Crew-5 | SpaceX | March 11, 2023 | | Shannon | | |
| 39 | Axiom Mission 2 | SpaceX | May 31, 2023 | | Megan | | | |
Uncrewed spacecraft
| Spacecraft | Agency | Landing date | Coordinates | Recovery ship | Miss distance |
|---|
Jupiter AM-18
(Able and Baker) | USAF | May 28, 1959 | 48to N Antigua Island | | 16km (10miles)[57] |
| Mercury-Big Joe | NASA | September 9, 1959 | 2407km (1,496miles) SE Cape Canaveral | | 925km (575miles)[58] |
| Mercury-Little Joe 2Sam The Rhesus Monkey | NASA | December 4, 1959 | 319km (198miles) SE Wallops Island, Virginia | | ? km[59] |
| Mercury-Redstone 1A | NASA | December 19, 1960 | 378.2km (235miles) SE Cape Canaveral | | 12.9km (08miles)[60] |
| Mercury-Redstone 2 | NASA | January 31, 1961 | 675.9km (420miles) SE Cape Canaveral | [61] | 209.2km (130miles)[62] |
| Mercury-Atlas 2 | NASA | February 21, 1961 | 2293.3km (1,425miles) SE Cape Canaveral | USS Donner | 20.9km (13miles)[63] |
Discoverer 25
(Corona 9017) | USAF | June 16, 1961 | | | mid-air recovery missed |
| Mercury-Atlas 4 | NASA | September 13, 1961 | 257.5km (160miles) E of Bermuda | | 64.4km (40miles)[64] |
| Mercury-Atlas 5 | NASA | November 29, 1961 | 804.7km (500miles) SE of Bermuda | | ? km[65] |
| Gemini 2 | NASA | January 19, 1965 | 16.565°N -95.27°W 3423.1km (2,127miles) downrange from KSC | USS Lake Champlain | 38.6km (24miles)[66] |
| AS-201 | NASA | February 26, 1966 | -8.18°N -11.15°W 8472km (5,264miles) downrange from KSC | USS Boxer | ? km |
| AS-202 | NASA | August 25, 1966 | 16.12°N 168.9°W 804.7km (500miles) southwest of Wake Island | USS Hornet | ? km[67] |
| Gemini 2-MOL | USAF | November 3, 1966 | 8149.7km (5,064miles) SE KSC near Ascension Island | | 11.26km (07miles)[68] |
| Apollo 4 | NASA | November 9, 1967 | 30.1°N -172.53°W | | 16km (10miles) |
| Apollo 6 | NASA | April 4, 1968 | 27.6667°N -216°W | USS Okinawa | ? km |
| Zond 5 | USSR | September 21, 1968 | -32.63°N 65.55°W | USSR recovery naval vessel and | 105km (65miles)[69] [70] |
| Zond 8 | USSR | October 27, 1970 | 730km (450miles) SE of the Chagos Archipelago, Indian Ocean | USSR recovery ship | 24 km[71] [72] |
| Cosmos 1374 | USSR | June 4, 1982 | -17°N 98°W 560km (350miles) S of Cocos Islands, Indian Ocean | USSR recovery ship | ? km |
| Cosmos 1445 | USSR | March 15, 1983 | 556km (345miles) S of Cocos Islands, Indian Ocean | USSR recovery ship | ? km |
| Cosmos 1517 | USSR | December 27, 1983 | near Crimea, Black Sea | USSR recovery ship | ? km |
| Cosmos 1614 | USSR | December 19, 1984 | ? km W of the Crimea, Black Sea | USSR recovery ship | ? km |
| COTS Demo Flight 1 | SpaceX | December 8, 2010 | 800km (500miles) west of Baja California, Mexico, Pacific Ocean | ? | 0.8km (00.5miles)[73] |
| Dragon C2+ | SpaceX | May 31, 2012 | 26.92°N -120.7°W | ? | ?[74] |
| CRS SpX-1 | SpaceX | October 28, 2012 | ? | American Islander[75] | ?[76] |
| CRS SpX-2 | SpaceX | March 27, 2013 | ? | American Islander | ?[77] |
| Exploration Flight Test 1 | NASA | December 5, 2014 | 23.6°N -116.4°W, 275miles west of Baja California | | |
| Crew Dragon Demo-1 | SpaceX | March 8, 2019 | In the Gulf of Mexico, off the coast of Pensacola, Florida | GO Searcher | |
| SpaceX CRS-21 | SpaceX | January 14, 2020 | In the Gulf of Mexico, off the coast of Tampa, Florida | GO Navigator | |
| Artemis I | NASA | December 11, 2022 | Pacific Ocean, west of Baja California | USS Portland | 4 nm | |
| IFT-4 | SpaceX | June 6, 2024 | Indian Ocean | |
See also
Notes and References
- Web site: NASA article about American launch sites . NASA . 2009-05-14 . 2020-08-07.
- Archived at Ghostarchive and the Wayback Machine: Web site: The Accidental Spacecraft Splashdown Which Almost Killed Its Crew. www.youtube.com.
- Web site: Soyuz-23, Lands On A Frozen Lake . VideoCosmos . 2012-06-21 . dead . https://web.archive.org/web/20120414220743/http://www.videocosmos.com/soyuz23.shtm . 2012-04-14 .
- Web site: Apollo 11 & 12 Recovery . Bob Fish . USS Hornet Museum's website.
- News: Cargo Dragon heads for splashdown off Florida's west coast. Spaceflight Now. Stephen. Clark. 12 January 2021. 14 January 2021.
- Web site: AUDIT OF COMMERCIAL RESUPPLY SERVICES TO THE INTERNATIONAL SPACE STATION. https://ghostarchive.org/archive/20221009/https://oig.nasa.gov/docs/IG-18-016.pdf . 2022-10-09 . live.
- Web site: Solar System Exploration: News & Events: News Archive: NASA Announces Key Decision For Next Deep Space Transportation System . https://web.archive.org/web/20110703185450/http://solarsystem.nasa.gov/news/display.cfm?News_ID=37403 . dead . 2011-07-03 . Solarsystem.nasa.gov . 2011-05-24 . 2012-06-21.
- Jain. U.. et al.. Journal of Fluid Mechanics. 2021. 938. 4. Air entrapment and its effect on pressure impulses in the slamming of a flat disc on water . A31 . 10.1017/jfm.2021.846. 2012.10137.
- Jain. U.. et al.. Physical Review Fluids. 2021. 6. 4. Air-cushioning effect and Kelvin-Helmholtz instability before the slamming of a disk on water . L042001 . 10.1103/PhysRevFluids.6.L042001. 2106.09551.
- Verhagen. J.H.G. Journal of Ship Research. 1967. The Impact of a Flat Plate on a Water Surface.
- Asryan . N.G.. Izv. Akad. Nauk Arm. SSR Mekh. 1972. Solid plate impact on surface of incompressible fluid in the presence of a gas layer between them.
- Ezell (1988) p. 143
- Ezell (1988) p. 144
- Ezell, Volume II, p. 145
- Ezell, Volume II, p. 146
- Ezell, Volume II, p. 147
- Ezell, Volume II, p. 148
- Ezell, Volume II, p. 159
- Ezell, Volume II, p. 160
- Ezell, Volume II, p. 161
- Ezell, Volume II, p. 162
- Ezell, Volume II, p. 163
- Ezell, Volume II, p. 164
- Ezell, Volume II, p. 165
- Ezell, Volume II, p. 166
- Ezell, Volume II, p. 167
- Ezell, Volume II, p. 168
- Ezell, Volume II, p. 188
- Ezell, Volume II, p. 189
- Ezell, Volume III, p. 83
- Orloff, p. 58
- Ezell, Volume III, p. 84
- Orloff, p. 78
- Ezell, Volume III, p. 85
- Orloff, p. 98
- Ezell, Volume III, p. 86
- Orloff, p. 120
- Ezell, Volume III, p. 87
- Orloff, p. 143
- Ezell, Volume III, p. 88
- Orloff, p. 168
- Ezell, Volume III, p. 89
- Orloff, p. 197
- Ezell, Volume III, p. 91
- Orloff, p. 225
- Ezell, Volume III, p. 92
- Orloff, p. 251
- Ezell, Volume III, p. 104
- Ezell, Volume III, p. 105
- Ezell, Volume III, p. 112
- https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19780009147_1978009147.pdf "ASTP Apollo Miss Distance"
- News: Cosmonauts Land in Lake, Blizzard . The Milwaukee Journal . October 18, 1976 . UPI.
- News: NASA Astronauts in SpaceX Capsule Make First Water Landing Since 1975 . The New York Times . August 2, 2020.
- News: SpaceX Dragon splashes down in Gulf of Mexico, bringing 4 astronauts home . Orlando Sentinel . May 2, 2021.
- News: SpaceX capsule returns four civilians from orbit, capping off first tourism mission . . September 18, 2021.
- Web site: Jackie Wattles . SpaceX's wildly busy year continues with astronaut splashdown . 2022-05-06 . CNN.
- News: Animals Survive 1,500-Mile Ride In Rocket Nose . The Windsor Daily Star . Windsor, Ontario . Associated Press . May 28, 1959.
- Web site: Big Joe Shot . nasa.gov . August 9, 2018.
- News: Monkey Completes Long Flight Aloft . Ellensburg Daily Record . Ellensburg, Washington . December 4, 1959.
- News: Man-In-Space Capsule To Be Closely Studied . Associated Press . The Florence Times . Florence, Alabama . December 20, 1960.
- Web site: USS Donner LSD20 . Homestead.com . 2012-06-21.
- News: Chimp Survives Space Shot . The Milwaukee Sentinel . Associated Press . February 1, 1961.
- News: Space Capsule Soars 107 Miles High . Associated Press . The Florence Times . Florence, Alabama . February 21, 1961.
- News: U.S. Robot Orbited, Returned . Meriden Journal . September 13, 1961.
- News: Capsule Trouble Forces Early Landing Of Craft . Associated Press . Toledo, Ohio . Toledo Blade . November 29, 1961.
- https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19650018359_1965018359.pdf "Gemini 2 Distance traveled, Landing Point, Miss Distance"
- Web site: Apollo-Saturn Unmanned Missions. Cheryl L.. Mansfield. January 9, 2018. NASA.
- News: Titan 3 Gives Spectacular Space Show . Sarasota, Florida . Sarasota Journal . November 3, 1966.
- Book: Michael Cassutt. Red Moon. 2007. Tom Doherty Associates. 978-1-4299-7172-0. 320.
- https://sse.jpl.nasa.gov/missions/profile.cfm?Sort=Alpha&Alias=Zond%2005&Letter=Z&Display=ReadMore "Zond 5, Landing Point, Miss Distance"
- Book: Brian Harvey. Soviet and Russian Lunar Exploration. 2007. Springer Science & Business Media. 978-0-387-73976-2. 218.
- https://sse.jpl.nasa.gov/missions/profile.cfm?Sort=Chron&MCode=Zond_08&StartYear=1970&EndYear=1979&Display=ReadMore "Zond 8, Landing Point"
- Web site: "COTS 1 (SpaceX Dragon 1), Splashdown area". https://web.archive.org/web/20101210214816/http://www.spacex.com/press.php?page=20101208. dead. December 10, 2010.
- Web site: History is made as Dragon splashes down safely in the Pacific! | Bad Astronomy | Discover Magazine . Blogs.discovermagazine.com . 2012-06-21 . dead . https://web.archive.org/web/20120705041532/http://blogs.discovermagazine.com/badastronomy/2012/05/31/history-is-made-as-dragon-splashes-down-safely-in-the-pacific/ . 2012-07-05 .
- Web site: American Island . marinetraffic.com . August 9, 2018.
- Web site: Dragon Returns to Earth . NASA. 2012-10-28 . 2012-10-29.
- Web site: SpaceX brings home Dragon with 2,700 pounds of cargo. Spaceflightnow. 2013-03-26 . 2013-03-27.
