Splashdown

For other uses, see Splashdown (disambiguation).

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.

Apollo 15 makes contact with the Pacific Ocean.

Locations of Atlantic Ocean splashdowns of American spacecraft prior to the 21st century

Locations of Pacific Ocean splashdowns of American spacecraft

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.^{[citation needed]}

Missions

Apollo 14 returns to Earth, 1971.

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 MV Retriever 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 USS Hornet and escorted safely inside a Mobile Quarantine Facility.^[4]

The splashdown of the SpaceX CRS-25 resupply mission

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 400 kilometers (250 mi). 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°13.7′N 75°53′W	USS Lake Champlain	5.6 km (3.5 mi)	[12]
2	Liberty Bell 7	NASA	July 21, 1961	27°32′N 75°44′W	USS Randolph	9.3 km (5.8 mi)	[13]
3	Friendship 7	NASA	February 20, 1962	21°26′N 68°41′W	USS Noa (USS Randolph**)	74	[14]
4	Aurora 7	NASA	May 24, 1962	19°27′N 63°59′W	USS John R. Pierce (USS Intrepid**)	400	[15]
5	Sigma 7	NASA	October 3, 1962	32°06′N 174°28′W	USS Kearsarge	7.4	[16]
6	Faith 7	NASA	May 16, 1963	27°20′N 176°26′W	USS Kearsarge	8.1	[17]
7	Gemini 3	NASA	March 23, 1965	22°26′N 70°51′W	USS Intrepid	111	[18]
8	Gemini 4	NASA	June 7, 1965	27°44′N 74°11′W	USS Wasp	81	[19]
9	Gemini 5	NASA	August 29, 1965	29°44′N 69°45′W	USS Lake Champlain	270	[20]
10	Gemini 7	NASA	December 18, 1965	25°25′N 70°07′W	USS Wasp	12	[21]
11	Gemini 6A	NASA	December 16, 1965	23°35′N 67°50′W	USS Wasp	13	[22]
12	Gemini 8	NASA	March 17, 1966	25°14′N 136°0′E	USS Leonard F. Mason (USS Boxer**)	2	[23]
13	Gemini 9A	NASA	June 6, 1966	27°52′N 75°0′W	USS Wasp	0.7	[24]
14	Gemini 10	NASA	July 21, 1966	26°45′N 71°57′W	USS Guadalcanal	6	[25]
15	Gemini 11	NASA	September 15, 1966	24°15′N 70°0′W	USS Guam	5	[26]
16	Gemini 12	NASA	November 15, 1966	24°35′N 69°57′W	USS Wasp	5	[27]
17	Apollo 7	NASA	October 22, 1968	27°32′N 64°04′W	USS Essex	3	[28]
18	Apollo 8	NASA	December 27, 1968	8°7.5′N 165°1.2′W	USS Yorktown	2	[29]
19	Apollo 9	NASA	March 13, 1969	23°15′N 67°56′W	USS Guadalcanal	5	[30][31]
20	Apollo 10	NASA	May 26, 1969	15°2′S 164°39′W	USS Princeton	2.4	[32][33]
21	Apollo 11	NASA	July 24, 1969	13°19′N 169°9′W	USS Hornet	3.13	[34][35]
22	Apollo 12	NASA	November 24, 1969	15°47′S 165°9′W	USS Hornet	3.7	[36][37]
23	Apollo 13	NASA	April 17, 1970	21°38′S 165°22′W	USS Iwo Jima	1.85	[38][39]
24	Apollo 14	NASA	February 9, 1971	27°1′S 172°39′W	USS New Orleans	1.1	[40][41]
25	Apollo 15	NASA	August 7, 1971	26°7′N 158°8′W	USS Okinawa	1.85	[42][43]
26	Apollo 16	NASA	April 27, 1972	0°43′S 156°13′W	USS Ticonderoga	0.55	[44][45]
27	Apollo 17	NASA	December 19, 1972	17°53′S 166°7′W	USS Ticonderoga	1.85	[46][47]
28	Skylab 2	NASA	June 22, 1973	24°45′N 127°2′W	USS Ticonderoga		[48]
29	Skylab 3	NASA	September 25, 1973	30°47′N 120°29′W	USS New Orleans		[49]
30	Skylab 4	NASA	February 8, 1974	31°18′N 119°48′W	USS New Orleans		[49]
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°48′N 87°30′W	GO Navigator		[53]
33	Crew Dragon Crew-1	SpaceX	May 2, 2021	29°32′N 86°11′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
40	Polaris Dawn	SpaceX	Sep 15, 2024

Uncrewed spacecraft

Spacecraft	Agency	Landing date	Coordinates	Recovery ship	Miss distance
Jupiter AM-18 (Able and Baker)	USAF	May 28, 1959	48 to 96 km (30 to 60 mi) N Antigua Island	USS Kiowa	16 km (9.9 mi)[57]
Mercury-Big Joe	NASA	September 9, 1959	2,407 km (1,496 mi) SE Cape Canaveral	USS Strong	925 km (575 mi)[58]
Mercury-Little Joe 2 Sam The Rhesus Monkey	NASA	December 4, 1959	319 km (198 mi) SE Wallops Island, Virginia	USS Borie	? km[59]
Mercury-Redstone 1A	NASA	December 19, 1960	378.2 km (235.0 mi) SE Cape Canaveral	USS Valley Forge	12.9 km (8.0 mi)[60]
Mercury-Redstone 2	NASA	January 31, 1961	675.9 km (420.0 mi) SE Cape Canaveral	USS Donner[61]	209.2 km (130.0 mi)[62]
Mercury-Atlas 2	NASA	February 21, 1961	2,293.3 km (1,425.0 mi) SE Cape Canaveral	USS Donner[61]	20.9 km (13.0 mi)[63]
Discoverer 25 (Corona 9017)	USAF	June 16, 1961			mid-air recovery missed
Mercury-Atlas 4	NASA	September 13, 1961	257.5 km (160.0 mi) E of Bermuda	USS Decatur	64.4 km (40.0 mi)[64]
Mercury-Atlas 5	NASA	November 29, 1961	804.7 km (500.0 mi) SE of Bermuda	USS Stormes	? km[65]
Gemini 2	NASA	January 19, 1965	16°33.9′N 49°46.27′W 3,423.1 km (2,127.0 mi) downrange from KSC	USS Lake Champlain	38.6 km (24.0 mi)[66]
AS-201	NASA	February 26, 1966	8°11′S 11°09′W 8,472 km (5,264 mi) downrange from KSC	USS Boxer	? km[67]
AS-202	NASA	August 25, 1966	16°07′N 168°54′E 804.7 km (500.0 mi) southwest of Wake Island	USS Hornet	? km[67]
Gemini 2-MOL	USAF	November 3, 1966	8,149.7 km (5,064.0 mi) SE KSC near Ascension Island	USS La Salle	11.26 km (7.00 mi)[68]
Apollo 4	NASA	November 9, 1967	30°06′N 172°32′W	USS Bennington	16 km (9.9 mi)[67]
Apollo 6	NASA	April 4, 1968	27°40′N 157°59′W	USS Okinawa	? km[67]
Zond 5	USSR	September 21, 1968	32°38′S 65°33′E	USSR recovery naval vessel Borovichy and Vasiliy Golovin	105 km (65 mi)[69][70]
Zond 8	USSR	October 27, 1970	730 km (450 mi) SE of the Chagos Archipelago, Indian Ocean	USSR recovery ship Taman	24 km[71][72]
Cosmos 1374	USSR	June 4, 1982	17°S 98°E 560 km (350 mi) S of Cocos Islands, Indian Ocean	USSR recovery ship	? km
Cosmos 1445	USSR	March 15, 1983	556 km (345 mi) 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	800 km (500 mi) west of Baja California, Mexico, Pacific Ocean	?	0.8 km (0.50 mi)[73]
Dragon C2+	SpaceX	May 31, 2012	26°55′N 120°42′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 / 23.6; -116.4 (EFT-1), 443 kilometres (275 mi) west of Baja California	USS Anchorage
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
IFT-5	SpaceX	October 13, 2024	Indian Ocean

Gallery

• 
  The Apollo 15 spacecraft splashed down safely despite a parachute failure. (NASA)
• 
  Apollo 15 splashdown (NASA)
• 
  Apollo 11 after splashdown (NASA)
• 
  Apollo 13 hoisted onto ship (NASA)
• 
  Gemini water egress training
• 
  Recovery of the Dragon C2+ on May 31, 2012
• 
  Recovery of the EFT-1 Orion, December 5, 2014
• 
  Landing of SpaceX Demo-2, 2 August 2020
• 
  Artemis II Orion capsule well dock Underway Recovery Test 10 (URT-10)

See also

• Spaceflight portal

• Apollo program
• Apollo–Soyuz Test Project
• Helicopter 66
• Project Gemini
• Project Mercury
• Skylab
• SpaceX Dragon 1
• SpaceX Dragon 2
• Water landing
• Zond program

Notes

1. "NASA article about American launch sites". NASA. May 14, 2009. Retrieved August 7, 2020.
2. Archived at Ghostarchive and the Wayback Machine: "The Accidental Spacecraft Splashdown Which Almost Killed Its Crew" – via www.youtube.com.
3. "Soyuz-23, Lands On A Frozen Lake". VideoCosmos. Archived from the original on April 14, 2012. Retrieved June 21, 2012.
4. Bob Fish. "Apollo 11 & 12 Recovery". USS Hornet Museum's website.
5. Clark, Stephen (January 12, 2021). "Cargo Dragon heads for splashdown off Florida's west coast". Spaceflight Now. Retrieved January 14, 2021.
6. "AUDIT OF COMMERCIAL RESUPPLY SERVICES TO THE INTERNATIONAL SPACE STATION" (PDF). Archived (PDF) from the original on October 9, 2022.
7. "Solar System Exploration: News & Events: News Archive: NASA Announces Key Decision For Next Deep Space Transportation System". Solarsystem.nasa.gov. May 24, 2011. Archived from the original on July 3, 2011. Retrieved June 21, 2012.
8. Jain, U.; et al. (2021). "Air entrapment and its effect on pressure impulses in the slamming of a flat disc on water". Journal of Fluid Mechanics. 938 (4): A31. arXiv:2012.10137. doi:10.1017/jfm.2021.846.
9. Jain, U.; et al. (2021). "Air-cushioning effect and Kelvin-Helmholtz instability before the slamming of a disk on water". Physical Review Fluids. 6 (4): L042001. arXiv:2106.09551. doi:10.1103/PhysRevFluids.6.L042001.
10. Verhagen, J.H.G (1967). "The Impact of a Flat Plate on a Water Surface". Journal of Ship Research.
11. Asryan, N.G. (1972). "Solid plate impact on surface of incompressible fluid in the presence of a gas layer between them". Izv. Akad. Nauk Arm. SSR Mekh.
12. Ezell (1988) p. 143
13. Ezell (1988) p. 144
14. Ezell, Volume II, p. 145
15. Ezell, Volume II, p. 146
16. Ezell, Volume II, p. 147
17. Ezell, Volume II, p. 148
18. Ezell, Volume II, p. 159
19. Ezell, Volume II, p. 160
20. Ezell, Volume II, p. 161
21. Ezell, Volume II, p. 162
22. Ezell, Volume II, p. 163
23. Ezell, Volume II, p. 164
24. Ezell, Volume II, p. 165
25. Ezell, Volume II, p. 166
26. Ezell, Volume II, p. 167
27. Ezell, Volume II, p. 168
28. Ezell, Volume II, p. 188
29. Ezell, Volume II, p. 189
30. Ezell, Volume III, p. 83
31. Orloff, p. 58
32. Ezell, Volume III, p. 84
33. Orloff, p. 78
34. Ezell, Volume III, p. 85
35. Orloff, p. 98
36. Ezell, Volume III, p. 86
37. Orloff, p. 120
38. Ezell, Volume III, p. 87
39. Orloff, p. 143
40. Ezell, Volume III, p. 88
41. Orloff, p. 168
42. Ezell, Volume III, p. 89
43. Orloff, p. 197
44. Ezell, Volume III, p. 91
45. Orloff, p. 225
46. Ezell, Volume III, p. 92
47. Orloff, p. 251
48. Ezell, Volume III, p. 104
49. Ezell, Volume III, p. 105
50. Ezell, Volume III, p. 112
51. "ASTP Apollo Miss Distance", ASTP Summary Science Report - Mission Description p. 36, Archived 2010-02-14 at the Wayback Machine
52. "Cosmonauts Land in Lake, Blizzard". The Milwaukee Journal. UPI. October 18, 1976.
53. "NASA Astronauts in SpaceX Capsule Make First Water Landing Since 1975". The New York Times. August 2, 2020.
54. "SpaceX Dragon splashes down in Gulf of Mexico, bringing 4 astronauts home". Orlando Sentinel. May 2, 2021.
55. "SpaceX capsule returns four civilians from orbit, capping off first tourism mission". CNN.com. September 18, 2021.
56. Jackie Wattles. "SpaceX's wildly busy year continues with astronaut splashdown". CNN. Retrieved May 6, 2022.
57. "Animals Survive 1,500-Mile Ride In Rocket Nose". The Windsor Daily Star. Windsor, Ontario. Associated Press. May 28, 1959.
58. "Big Joe Shot". nasa.gov. Retrieved August 9, 2018.
59. "Monkey Completes Long Flight Aloft". Ellensburg Daily Record. Ellensburg, Washington. December 4, 1959.
60. "Man-In-Space Capsule To Be Closely Studied". The Florence Times. Florence, Alabama. Associated Press. December 20, 1960.
61. "USS Donner LSD20". Homestead.com. Retrieved June 21, 2012.
62. "Chimp Survives Space Shot". The Milwaukee Sentinel. Associated Press. February 1, 1961.
63. "Space Capsule Soars 107 Miles High". The Florence Times. Florence, Alabama. Associated Press. February 21, 1961.
64. "U.S. Robot Orbited, Returned". Meriden Journal. September 13, 1961.
65. "Capsule Trouble Forces Early Landing Of Craft". Toledo Blade. Toledo, Ohio. Associated Press. November 29, 1961.
66. "Gemini 2 Distance traveled, Landing Point, Miss Distance", Manned Space Flight Network Performance Analysis for the GT-2 Mission; Pg V - Distance traveled, Page 21 - Landing Point, Miss Distance, (NASA X-552-65-204)
67. Mansfield, Cheryl L. (January 9, 2018). "Apollo-Saturn Unmanned Missions". NASA.
68. "Titan 3 Gives Spectacular Space Show". Sarasota Journal. Sarasota, Florida. November 3, 1966.
69. Michael Cassutt (2007). Red Moon. Tom Doherty Associates. p. 320. ISBN 978-1-4299-7172-0.
70. "Zond 5, Landing Point, Miss Distance" Archived 2011-09-27 at the Wayback Machine, NASA Solar System Exploration - Zond 5, Landing Point, Miss Distance.
71. Brian Harvey (2007). Soviet and Russian Lunar Exploration. Springer Science & Business Media. p. 218. ISBN 978-0-387-73976-2.
72. "Zond 8, Landing Point" Archived 2011-09-27 at the Wayback Machine, NASA Solar System Exploration - Zond 8, Splashdown area.
73. ""COTS 1 (SpaceX Dragon 1), Splashdown area"". Archived from the original on December 10, 2010.
74. "History is made as Dragon splashes down safely in the Pacific! | Bad Astronomy | Discover Magazine". Blogs.discovermagazine.com. Archived from the original on July 5, 2012. Retrieved June 21, 2012.
75. "American Island". marinetraffic.com. Retrieved August 9, 2018.
76. "Dragon Returns to Earth". NASA. October 28, 2012. Retrieved October 29, 2012.
77. "SpaceX brings home Dragon with 2,700 pounds of cargo". Spaceflightnow. March 26, 2013. Retrieved March 27, 2013.

Bibliography

• Ezell, Linda Neumann (1988), NASA Historical Data Book (PDF), vol. II Programs and Projects 1958 - 1968 (NASA SP-4012), archived (PDF) from the original on October 9, 2022
• Ezell, Linda Neumann (1988), NASA Historical Data Book (PDF), vol. III - Programs and Projects 1969 - 1978 (SP-4012), archived (PDF) from the original on October 9, 2022
• Orloff, Richard W., Apollo By The Numbers - A Statistical Reference (NASA SP-2000-4029) (PDF), p. 143, archived (PDF) from the original on October 9, 2022

External links

• The dictionary definition of splashdown at Wiktionary