Cape Canaveral Space Launch Complex 37

Space Launch Complex 37

Delta IV Heavy lifts off from SLC-37B in June 2016 carrying NROL-37
Launch site	Cape Canaveral Space Force Station
Location	28°31′55″N80°34′01″W / 28.531986°N 80.566821°W / 28.531986; -80.566821
Time zone	UTC−05:00 (EST)
• Summer (DST)	UTC−04:00 (EDT)
Short name	SLC-37
Operator	United States Space Force
Total launches	43
Orbital inclination range	28° - 57°
LC-37A launch history Status Demolished Launches None First launch Unused Associated rockets Proposed: Starship [1] Plans cancelled: Saturn I, Saturn IB SLC-37B launch history Status Inactive Launches 43 First launch 29 January 1964 Saturn I (SA-5) Last launch 9 April 2024 Delta IV Heavy (NROL-70) Associated rockets Proposed: Starship [1] Retired: Saturn I, Saturn IB, Delta IV, Delta IV Heavy

Space Launch Complex 37 ^{[2] [3]} (SLC-37), previously Launch Complex 37 (LC-37), is a launch complex on Cape Canaveral Space Force Station, Florida. Originally built to support the Apollo program, the complex consists of two launch pads: LC-37A and SLC-37B. Pad 37A has never been used, while 37B hosted Saturn I and Saturn IB launches in the 1960s as well as Delta IV and Delta IV Heavy launches from 2002 to 2024.

As of July 2025, the pad is not officially leased to anyone. However, SpaceX is expected to become the next tenant of SLC-37 for use as a launch site for Starship, so far possessing a limited right of entry, to begin demolition of existing structures, as it prepares a draft environmental impact statement. ^[4]

History

Saturn I and IB (1964–1968)

Launch Complex 37 began construction in 1959, being envisioned to be a second site to launch the experimental heavy-lift Saturn rockets, joining Launch Complex 34 (LC-34) to the south. Originally, it was planned to be the launch site for an Earth orbit rendezvous (EOR) strategy to potentially be taken by the Apollo program, where a launch vehicle such as the Saturn C-3 would launch both the trans-lunar injection stage and the Lunar Excursion Module from the two pads, while the crew would lift off from LC-34 and intercept the two payloads in low Earth orbit. Despite NASA opting for a Lunar orbit rendezvous (LOR) approach and using the Saturn V from Launch Complex 39 to the north, they nonetheless accepted LC-37 to support the Saturn I program in 1963. ^[5]

Apollo 5 at LC-37B in 1968

The original layout of the launch complex featured one Mobile Service Structure which could be used to service or mate a rocket on either LC-37A or 37B, but not on both simultaneously. The first launch from LC-37 came on January 29, 1964, launching Saturn I SA-5 as part of the rocketry development portion of the Apollo program. Over the next two years, a total of six uncrewed Saturn I flights were launched from the complex, mostly carrying boilerplate Apollo capsules alongside the three launches of the Pegasus project.

In late 1965, both LC-37 and LC-34 were modified to launch the Saturn I's successor, the Saturn IB. Similarly to its previous configuration, this was in support of Apollo development before the Saturn V's activation at Kennedy Space Center; however, the original purpose of EOR was also made ready as a backup in case complications render the Saturn V and LOR unfeasible. Only two Saturn IB launches were made from LC-37: the first one was AS-203 (or informally Apollo 3), which launched on July 5, 1966 and tested engine restart capabilities on the S-IVB upper stage. The second one was Apollo 5, lifting off on January 22, 1968 and carrying the first operational test of the Apollo Lunar Module in space. ^[5] The facility was deactivated in 1972, following the conclusion of the Apollo program. Proposals were drawn of resuming Saturn IB launches from LC-37 and LC-34 as part of the Apollo Applications Program, but NASA instead opted to modify Launch Complex 39B for that role. LC-37 would sit dormant for the next 30 years.

Delta IV and Delta IV Heavy (2002–2024)

In 1998, the United States Air Force and Boeing came into an agreement to use LC-37 for launching the Delta IV as part of the Evolved Expendable Launch Vehicle program, getting rechristened as SLC-37 as a result of doing so. Having acquired the Delta family following their merger with McDonnell Douglas the previous year, Boeing aimed for the Delta IV to be a complement and not a replacement to the other active members of the time, the Delta II and Delta III. As such (and taking the difference in lift capabilities into account), a new launch site similar in size to SLC-37 was needed rather than continuing to use Space Launch Complex 17 (SLC-17). Facility modifications were made to SLC-37B in 2001, constructing a 330 ft (100 m) tall Mobile Service Tower fitted to service all planned Delta IV configurations. ^[6] The complex was officially put into active service with the first launch of the Delta IV on November 20, 2002, carrying Eutelsat 70A to geostationary transfer orbit.

On December 21, 2004, SLC-37 supported the maiden flight of the Delta IV Heavy, which aimed at carrying a boilerplate and an assortment of small satellites into orbit. The next year, citing issues that sprang up with competition, Boeing announced that Delta operations at the pad and at SLC-17 would be combined with those of Atlas V at Space Launch Complex 41 (SLC-41) as part of a joint venture with Lockheed Martin. This handover would be made official with the establishment of United Launch Alliance (ULA) in December 2006, and SLC-37 supported its first launch under ULA with a Delta IV Heavy flight on November 11, 2007.

During the Delta IV era, SLC-37 underwent 35 launches of the family, consisting of 29 Medium launches and 16 Heavy launches. ^[7] Almost all payloads launched were governmental in nature, with a majority of that subsection being military customers such as the Air Force, the United States Navy, and the National Reconnaissance Office. Some notable missions launched from the facility include GOES-N, GOES-O, and GOES-P for NOAA throughout the late 2000s, Exploration Flight Test-1 for NASA's Orion spacecraft in 2014, and the Parker Solar Probe in 2018.

Throughout the late 2010s and early 2020s, ULA began to wind down operations at the complex in preparation for the Delta IV's retirement. Their new launch vehicle to replace the Delta and Atlas families, Vulcan Centaur, was planning on having its launch site be at SLC-41 and as such ULA opted to let the SLC-37 lease expire. The final Delta IV Medium launch came on August 22, 2019 carrying a GPS satellite for the Air Force, while the last overall launch of the Delta family came with a Delta IV Heavy launch for the NRO on April 9, 2024. ^[8]

Proposals for Starship (from 2025)

During the lead up to the Delta IV's retirement, the United States Space Force (having taken over the Air Force's jurisdiction at Cape Canaveral) and SpaceX began evaluating SLC-37 as a potential launch site for Starship. This would complement SpaceX's existing operations at Starbase and its plans for Launch Complex 39A at Kennedy Space Center. As part of the process, the Federal Aviation Administration was tasked with preparing an environmental impact statement (EIS). ^[9] The draft EIS, initially expected in December 2024, was released in June 2025. ^{[10] [11]} An official lease announcement is expected to occur following the final study's release in September 2025. ^[4]

SpaceX plans to construct two launch pads with integration towers on the eastern portion of SLC-37, designed to support a potential flight cadence of up to 76 launches per year. ^[1] In March 2025, SpaceX announced it had received a limited right of entry for SLC-37, which it has used to begin demolition and site clearing. ^{[12] [13]} On June 12, the mobile service structure and lightning towers for the Delta IV pad were imploded in a controlled demolition. ^[14]

Launch statistics

Launch sites at Cape Canaveral Space Force Station and Kennedy Space Center

4km
2.5miles

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

   

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• talk
• edit

  Active pads

  Active pads not used for launches

  Inactive leased pads

  Inactive unleased pads

1

LC-39B

2

LC-39A

3

LC-48

4

SLC-41

5

SLC-40

6

LC-47

7

SLC-37

8

LC-34

9

SLC-20

10

LC-19

11

LC-16

12

LC-15

13

LC-14

14

LC-13 (LZ-2)

15

LC-12

16

LC-11

17

LC-36

18

LC-1, LC-2, LC-3, and LC-4

19

SLC-46

20

LC-21 and LC-22

21

LC-31 and LC-32

22

LC-18

23

SLC-17

24

LC-26

25

LC-5 and LC-6

26

LC-30

27

LC-25

28

LC-29

Rocket configuration

1

2

3

4

1965

1970

2000

2005

2010

2015

2020

•   Saturn I
•   Saturn IB
•   Delta IV
•   Delta IV Heavy

List of launches

Saturn I and IB

All flights operated by NASA.

No.	Date	Time (UTC)	Vehicle	Serial Number	Mission	Result	Remarks
1	29 January 1964	16:25	Saturn I	SA-5	SA-5	Success	First launch from LC-37 and first Block II Saturn I flight. First orbital Saturn launch and first with a live S-IV. Flight notable for being referred to by John F. Kennedy as the one that would place American lift capability ahead of the Soviets.
2	28 May 1964	17:07	Saturn I	SA-6	AS-101	Success	First Saturn I flight with a boilerplate version of the Apollo CSM. One H-1 engine failed during ascent, but mission performed nominally otherwise.
3	18 September 1964	16:22	Saturn I	SA-7	AS-102	Success	Boilerplate CSM flight.
4	16 February 1965	14:37	Saturn I	SA-8	AS-103	Success	Boilerplate CSM flight. Carried Pegasus 1 as a secondary payload attached to the S-IV, designed to study micrometeoroid impacts.
5	25 May 1965	07:35	Saturn I	SA-9	AS-104	Success	Boilerplate CSM flight. Carried Pegasus 2 as a secondary payload attached to the S-IV, designed to study micrometeoroid impacts.
6	30 July 1965	13:00	Saturn I	SA-10	AS-105	Success	Boilerplate CSM flight. Carried Pegasus 3 as a secondary payload attached to the S-IV, designed to study micrometeoroid impacts. Last flight of the Saturn I.
7	5 July 1966	14:53	Saturn IB	SA-203	AS-203	Success	Mission to test restart capabilities of the S-IVB to simulate trans-lunar injection. First Saturn IB launch from LC-37, and only Saturn IB launch without a payload. Also occasionally known as Apollo 3.
8	22 January 1968	22:48	Saturn IB	SA-204	Apollo 5	Success	Mission to test the lunar module in low Earth orbit. First Saturn IB flight following the Apollo 1 fire, and used Apollo 1's intended rocket for flight. Last unmanned Saturn IB launch, and last Saturn launch from LC-37.

Delta IV

All launches before 2006 operated by Boeing. All launches since 2007 operated by United Launch Alliance.

No.	Date	Time (UTC)	Vehicle	Configuration	Payload [15]	Result [15]	Remarks
9	20 November 2002	22:39	Delta IV	Medium+ (4,2)	Eutelsat W5	Success [16]	Maiden flight of the Delta IV, and first commercial launch from SLC-37. First Delta flight not using Thor-based architecture.
10	11 March 2003	00:59	Delta IV	Medium	DSCS-3 A3	Success [17]	First military launch from SLC-37.
11	29 August 2003	23:13	Delta IV	Medium	DSCS-3 B6	Success [18]
12	21 December 2004	21:50	Delta IV Heavy	Heavy	DemoSat	Partial failure	Contained two 3 Corner Satellites, nicknamed Sparkie and Ralphie, as secondary payloads. Maiden flight of the Delta IV Heavy. Common Booster Cores underperformed, placing primary satellite in incorrect orbit and failing to put secondary satellites into orbit.
13	24 May 2006	22:11	Delta IV	Medium+ (4,2)	GOES-13	Success [19]	Launched as GOES-N. Part of the Geostationary Operational Environmental Satellites system of satellites. First GOES launch on a Delta rocket since GOES-7.
14	11 November 2007	01:50	Delta IV Heavy	Heavy	DSP-23	Success	First Delta IV launch following the creation of United Launch Alliance.
15	18 January 2009	02:47	Delta IV Heavy	Heavy	NROL-26	Success	NRO launch. Orion satellite, also known as USA-202. First National Reconnaissance Office launch from SLC-37, and first on a Delta IV Heavy.
16	27 June 2009	22:51	Delta IV	Medium+ (4,2)	GOES-14	Success [20]	Launched as GOES-O. Part of the Geostationary Operational Environmental Satellites system of satellites.
17	6 December 2009	01:47	Delta IV	Medium+ (5,4)	WGS-3	Success [21]
18	4 March 2010	23:57	Delta IV	Medium+ (4,2)	GOES-15	Success [22]	Launched as GOES-P. Part of the Geostationary Operational Environmental Satellites system of satellites.
19	28 May 2010	3:00	Delta IV	Medium+ (4,2)	GPS IIF SV-1	Success [23]	Part of the Global Positioning System. First GPS launch on a Delta IV.
20	21 November 2010	22:58	Delta IV Heavy	Heavy	NROL-32	Success	NRO launch. Orion satellite, also known as USA-223.
21	11 March 2011	23:38	Delta IV	Medium+ (4,2)	NROL-27	Success	NRO launch. SDS satellite, also known as USA-227.
22	16 July 2011	06:41	Delta IV	Medium+ (4,2)	GPS IIF-2	Success [24]	Part of the Global Positioning System.
23	20 January 2012	00:38	Delta IV	Medium+ (5,4)	WGS-4	Success [25]
24	29 June 2012	13:15	Delta IV Heavy	Heavy	NROL-15	Success	NRO launch. Orion satellite, also known as USA-237.
25	4 October 2012	12:10	Delta IV	Medium+ (4,2)	GPS IIF-3	Success [26]	Part of the Global Positioning System.
26	25 May 2013	00:27	Delta IV	Medium+ (5,4)	WGS-5	Success [27]
27	8 August 2013	00:29	Delta IV	Medium+ (5,4)	WGS-6	Success [28]
28	21 February 2014	01:59	Delta IV	Medium+ (4,2)	GPS IIF-5	Success [29]	Part of the Global Positioning System.
29	17 May 2014	00:03	Delta IV	Medium+ (4,2)	GPS IIF-6	Success [30]	Part of the Global Positioning System.
30	28 July 2014	23:28	Delta IV	Medium+ (4,2)	USA 253 to USA-255 (AFSPC-4 (GSSAP #1/#2/ANGELS))	Success [31]
31	5 December 2014	12:05	Delta IV Heavy	Heavy	Exploration Flight Test-1	Success	Test flight of an Orion capsule, demonstrating flight operations in space and beyond low Earth orbit in anticipation for future operations with the Space Launch System. Maiden flight of an Orion capsule and what would eventually become the Artemis Program. Payload fairings replaced with capsule, launch escape system, and boilerplate European Service Module.
32	25 March 2015	18:36	Delta IV	Medium+ (4,2)	GPS IIF-9	Success [32]	Part of the Global Positioning System.
33	24 July 2015	00:07	Delta IV	Medium+ (5,4)	WGS-7	Success [33]
34	11 June 2016	17:51	Delta IV Heavy	Heavy	NROL-37	Success	NRO launch. Orion satellite, also known as USA-268.
35	19 August 2016	04:52	Delta IV	Medium+ (4,2)	USA-270 and USA-271 (AFSPC-6 (GSSAP #3/#4))	Success [34]
36	7 December 2016	23:53	Delta IV	Medium+ (5,4)	WGS-8	Success [35]
37	19 March 2017	00:18	Delta IV	Medium+ (5,4)	WGS-9	Success [36]
38	12 August 2018	07:31	Delta IV Heavy	Heavy	Parker Solar Probe	Success	Part of the Large Strategic Science Missions and the Living With a Star program, aimed at studying the corona of the Sun. Only heliocentric launch of the Delta IV, last heliocentric launch of the Delta family, and first from SLC-37. Holds the current proximity record to the Sun at 9.8 solar radii (6.9 million km), and fastest traveling artificial object at 191 km/s (0.064c).
39	16 March 2019	00:26	Delta IV	Medium+ (5,4)	WGS-10	Success [37]
40	22 August 2019	13:06	Delta IV	Medium+ (4,2)	GPS III-2	Success [38]	Part of the Global Positioning System. Last GPS launch on a Delta rocket, and last Delta IV Medium launch.
41	11 December 2020	01:09	Delta IV Heavy	Heavy	NROL-44	Success	NRO launch. Orion satellite, also known as USA-311. [39] [40]
42	22 June 2023	09:18	Delta IV Heavy	Heavy	NROL-68	Success	NRO launch. Orion satellite, also known as USA-345.
43	9 April 2024	16:53	Delta IV Heavy	Heavy	NROL-70	Success	NRO launch. Orion satellite, also known as USA-353. Last flight of the Delta IV, and last flight of the Delta family.

Photos

• 
  Map of Launch Complex 37 of the 1960s, with original Mobile Service Structure
• 
  The launch of AS-103 with the Pegasus 1 satellite atop a Saturn I, from LC-37B in 1965
• 
  The launch of GOES-N atop a Delta IV, from SLC-37B in 2006
• 
  SLC-37B in 2010, with the Mobile Service Tower

See also

• List of spaceflights by year
• List of Cape Canaveral and Merritt Island launch sites
• Project Apollo
• Cape Canaveral Launch Complex 34

References

1. "Space Force Starship EIS – Environmental Impact Statement for SpaceX Starship-Super Heavy Operations at Cape Canaveral Space Force Station" . Retrieved 2025-06-10.
2. McDowell, Jonathan (1998-02-22). "Issue 350". Jonathan's Space Report. Jonathan's Space Page. Archived from the original on 2010-05-03. Retrieved 2009-07-09.
3. "Delta-IV Heavy to launch last DSP satellite". www.afspc.af.mil. Archived from the original on September 30, 2011.
4. Clark, Stephen (June 9, 2025). "Prepping for Starship, SpaceX is about to demolish one of ULA's launch pads". Ars Technica . New York: Condé Nast. Archived from the original on June 11, 2025. Retrieved June 13, 2025.
5. "Complex 37 -- Cape Canaveral Air Station". Federation of American Scientists (www.fas.org). 2000-06-16. Archived from the original on 2008-04-20. Retrieved 2008-05-28.
6. "Boeing, Raytheon Top Off Nation's Newest Launch Tower". Boeing. March 2, 2000. Archived from the original on 2008-12-02.
7. "Launch Complex 37". Cape Canaveral Space Force Museum. Retrieved September 30, 2023.
8. "Delta IV Medium's well-earned retirement with GPS finale". NASASpaceflight. 22 August 2019. Retrieved September 30, 2023.
9. Foust, Jeff (2024-02-17). "Space Force to study Cape Canaveral launch sites for Starship". SpaceNews. Retrieved 2025-06-12.
10. SpaceX (3 March 2025). "Future of Building Starship". spacex.com.
11. Stone, Mark (2024-03-17). "Starship Coming to Florida". Hernando Sun. Retrieved 2024-04-14.
12. SpaceflightNow [@SpaceflightNow] (6 June 2025). "The @usairforce published its Draft Environmental Impact Statement on SpaceX's proposal to use pad 37 at Cape Canaveral Space Force Station to launch Starship-Super Heavy up to 76 times annually. Public review runs now through July 28. Documents: https://spaceforcestarshipeis.com" (Tweet). Retrieved 12 June 2025– via Twitter.
13. Romera, Alejandro Alcantarilla (2025-06-11). "From Delta to Starship, SpaceX's ambitious plan for SLC-37's future". NASASpaceFlight.com. Retrieved 2025-06-12.
14. Evans, Max [@_mgde_] (12 June 2025). "END OF AN ERA: former ULA infrastructure at SLC-37, used to launch the Delta IV family of launch vehicles, was demolished this morning at the Cape Canaveral Space Force Station. It has been given new life with SpaceX and the Starship program. Lots to look forward to! 📸- @NASASpaceflight 📺 - http://nsf.live/spacecoast" (Tweet). Retrieved 12 June 2025– via Twitter.
15. Krebs, Gunter. "Delta-4". Gunter's Space Page. Retrieved 15 March 2018.
16. "Boeing's Delta 4 rocket debuts successfully". Spaceflight Now. November 20, 2002.
17. "Delta 4 rocket successfully begins military service". Spaceflight Now. March 10, 2003.
18. "Delta 4 rocket delivers last Air Force DSCS satellite". Spaceflight Now. August 29, 2003.
19. "Weather observatory for Americas ascends to space". Spaceflight Now. May 24, 2006.
20. "NASA and NOAA's GOES-O Satellite Successfully Launched". NASA KSC. 2009-06-27. Archived from the original on 2009-06-29. Retrieved 2024-07-14.
21. Ray, Justin (2009-12-05). "New communications craft launched for U.S. military". Spaceflight Now. Retrieved 2009-12-06.
22. "United Launch Alliance Successfully Launches NASA/NOAA Weather Satellite Mission". United Launch Alliance. 4 March 2010. Archived from the original on 7 December 2013. Retrieved 3 February 2013.
23. "ULA Marks Delta 50th Anniversary with Successful Delta IV GPS IIF SV-1 Launch". United Launch Alliance. 27 May 2010. Archived from the original on 7 December 2013. Retrieved 3 February 2013.
24. "United Launch Alliance Marks the 50th Successful GPS Launch for the Air Force with the Delivery of the GPS IIF-2 Mission to orbit". United Launch Alliance. 16 July 2011. Archived from the original on 7 December 2013. Retrieved 16 July 2011.
25. "United Launch Alliance Delta IV Rocket Successfully Launches US Air Force's Wideband Global SATCOM-4 (WGS-4) Satellite". United Launch Alliance. 19 January 2012. Archived from the original on 7 December 2013. Retrieved 2 February 2013.
26. "United Launch Alliance Delta IV Rocket Successfully Launches Global Positioning System Satellite for the U.S. Air Force". United Launch Alliance. 4 October 2012. Archived from the original on 7 December 2013. Retrieved 4 October 2012.
27. "United Launch Alliance Launches Second Successful Mission for U.S. Air Force in Just Nine Days". United Launch Alliance. 24 May 2013. Archived from the original on 7 December 2013. Retrieved 25 May 2013.
28. "United Launch Alliance Successfully Launches Second Wideband Global SATCOM Mission for U.S. Air Force in Less Than Three Months". United Launch Alliance. 8 August 2013. Archived from the original on 7 December 2013. Retrieved 8 August 2013.
29. "United Launch Alliance Successfully Launches 25th Delta IV Mission Carrying Global Positioning System Satellite for the U.S. Air Force". United Launch Alliance. 21 February 2014. Archived from the original on 7 December 2013. Retrieved 21 February 2014.
30. "United Launch Alliance Successfully Launches Second Global Positioning System Satellite for the U.S. Air Force in Less Than Three Months". United Launch Alliance. 16 May 2014. Archived from the original on 17 May 2014. Retrieved 18 May 2014.
31. "United Launch Alliance Marks 85th Successful Launch by Delivering Three Satellites into Orbit for the U.S. Air Force". United Launch Alliance. 29 July 2014. Archived from the original on 5 August 2014. Retrieved 29 July 2014.
32. "United Launch Alliance Successfully Launches Second Mission in Less than Two Weeks". United Launch Alliance. 26 March 2015. Archived from the original on 12 January 2018. Retrieved 26 March 2015.
33. "United Launch Alliance Successfully Launches WGS-7". United Launch Alliance. 23 July 2015. Archived from the original on 12 January 2018. Retrieved 25 July 2015.
34. "United Launch Alliance Successfully Launches AFSPC6 Mission for the U.S. Air Force". United Launch Alliance. 19 August 2016. Retrieved 19 August 2016.
35. "United Launch Alliance Successfully Launches WGS8 Mission for the U.S. Air Force". United Launch Alliance . 7 December 2016. Retrieved 7 December 2016.
36. "Delta IV to Launch WGS-9 for the U.S. Air Force". United Launch Alliance . 18 March 2017. Retrieved 18 November 2017.
37. "United Launch Alliance Successfully Launches WGS-10 Mission". United Launch Alliance . 16 March 2019. Retrieved 16 March 2019.
38. "United Launch Alliance Successfully Launches GPS III Satellite for U.S. Air Force Space and Missile Systems Center". United Launch Alliance . 22 August 2019. Retrieved 22 August 2019.
39. "Launch Schedule". Spaceflight Now. 27 October 2020. Retrieved 31 October 2020.
40. "Launch Mission Execution Forecast". 45th Weather Squadron – Patrick Air Force Base. 30 October 2020. Retrieved 31 October 2020. This article incorporates text from this source, which is in the public domain .

External links

• Boeing Delta IV website