Delta IV Heavy

The Delta IV Heavy (Delta 9250H) is an expendable heavy-lift launch vehicle, the largest type of the Delta IV family and the world's second highest-capacity rocket in operation, behind SpaceX's Falcon Heavy rocket.[4][5] It is manufactured by United Launch Alliance and was first launched in 2004.[6]

Delta IV Heavy

Delta IV Heavy launches from Vandenberg AFB
Function	Orbital heavy-lift launch vehicle
Manufacturer	United Launch Alliance
Country of origin	United States
Cost per launch	US$350 million [1] NRO: $440 million
Cost per year	2018
Size
Height	72 m (236 ft)
Diameter	5 m (16 ft)
Width	15 m (49 ft)
Mass	733,000 kg (1,616,000 lb)
Stages	2+
Capacity
Payload to LEO	28,790 kg (63,470 lb)
Payload to GTO	14,220 kg (31,350 lb)
Associated rockets
Family	Delta IV
Comparable	Ariane 5 Falcon Heavy Long March 5 Proton-M
Launch history
Status	Active
Launch sites	Cape Canaveral, SLC-37B VAFB, SLC-6
Total launches	11
Successes	10
Partial failures	1
First flight	21 December 2004 (USA-181)
Last flight	19 January 2019 (NROL-71)
Notable payloads	EFT-1 NRO classified payloads Kennen Orion Parker Solar Probe
Boosters (CBC)
No. boosters	2
Length	40.8 m (134 ft)
Diameter	5.1 m (17 ft)
Empty mass	26,000 kg (57,000 lb)
Gross mass	226,400 kg (499,100 lb)
Propellant mass	200,400 kg (441,800 lb) [2]
Engines	1 RS-68A
Thrust	3,140 kN (710,000 lbf)
Total thrust	6,280 kN (1,410,000 lbf)
Specific impulse	Sea level: 360 s (3.5 km/s) Vacuum: 412 s (4.04 km/s)
Burn time	242 seconds [3]
Fuel	LH2 / LOX
First stage (CBC)
Length	40.8 m (134 ft)
Diameter	5.1 m (17 ft)
Gross mass	226,400 kg (499,100 lb)
Propellant mass	200,400 kg (441,800 lb)
Engines	1 RS-68A
Thrust	3,140 kN (710,000 lbf)
Specific impulse	Sea level: 360 s (3.5 km/s) Vacuum: 412 s (4.04 km/s)
Burn time	328 seconds
Fuel	LH2 / LOX
Second stage (DCSS)
Length	13.7 m (45 ft)
Diameter	5.1 m (17 ft)
Gross mass	30,700 kg (67,700 lb)
Propellant mass	27,220 kg (60,010 lb)
Engines	1 RL10-B-2
Thrust	110 kN (25,000 lbf)
Specific impulse	462 s (4.53 km/s)
Burn time	1125 seconds
Fuel	LH2 / LOX

The Delta IV Heavy consists of a central Common Booster Core (CBC), with two additional CBCs as liquid rocket boosters instead of the GEM-60 solid rocket motors used by the Delta IV Medium+ versions. At lift off, all three cores operate at full thrust, and 44 seconds later the center core throttles down to 55% to conserve fuel until booster separation. The boosters burn out at 242 seconds after launch and are separated as the core booster throttles back up to full thrust. The core burns out 86 seconds later, and the second stage completes the ascent to orbit.[3]

The rocket uses 3 RS-68 engines, one in the central core and one in each booster.

History

Delta IV Heavy for EFT-1, 2014

The Delta IV line of rockets was developed by McDonnell Douglas, later United Launch Alliance. The Delta IV Heavy is the most powerful member of the line, which also includes the smaller Delta IV Medium.[7] The Delta IV Heavy can lift 28,370 kg (62,540 lbs) to low Earth orbit and 13,810 kg (30,440 lbs) to geostationary transfer orbit.[7] It is an all liquid-fueled rocket, consisting of an upper stage, one main booster and two strap-on boosters.[7]

The first launch of the Delta IV Heavy in 2004 carried a boilerplate payload and failed to reach intended orbit. Cavitation in the liquid-oxygen propellant lines caused shutdown of both boosters eight seconds early, and the core engine nine seconds early; this resulted in a lower staging velocity for which the second stage was unable to compensate. The payload was left in a lower than intended orbit.[8] Its first operational payload was the DSP-23 satellite, successfully launched in 2007; it was then used to launch a further five visual and electronic reconnaissance satellites for the National Reconnaissance Office through 2013.

In December 2014, the Delta IV Heavy was used to launch an uncrewed test flight of the Orion spacecraft, designated EFT-1. After several delays on 4 December 2014,[9] the mission was successfully launched at 12:05 UTC on 5 December 2014.[10]

Capability

Capacity of the Delta IV Heavy:

• Low Earth orbit (LEO), 200 km × 28.7°: 28,790 kilograms (63,470 lb) [11]
• Low Earth orbit (ISS), 407 km × 51.6°: 25,980 kilograms (57,280 lb) [12]
• Geosynchronous transfer orbit (GTO): 14,220 kilograms (31,350 lb)[11]
• Geosynchronous orbit (GEO): 6,750 kilograms (14,880 lb) [11]
• Lunar transfer orbit (LTO): 10,000 kilograms (22,000 lb)
• Mars transfer orbit: 8,000 kilograms (17,600 lb)[13]

The Delta IV Heavy's total mass at launch is approximately 733,000 kilograms (1,616,000 lb).

Launch history

Main article: List of Thor and Delta launches

Flight No.	Date	Payload[14]	Mass	Launch site	Outcome[14]
1	21 December 2004	DemoSat, Sparkie / 3CS-1 and Ralphie / 3CS-2	~6000 kg	Cape Canaveral, SLC-37B	Partial failure[lower-alpha 1]
2	11 November 2007	DSP-23 Defense Support Program	5250 kg	Cape Canaveral, SLC-37B	Success
3	18 January 2009	Orion 6 / Mentor 4 (USA-202 / NROL-26)	Classified	Cape Canaveral, SLC-37B	Success
4	21 November 2010	Orion 7 / Mentor 5 (USA-223 / NROL-32)	Classified	Cape Canaveral, SLC-37B	Success
5	20 January 2011	KH-11 Kennen 15 (USA-224 / NROL-49)	<17000 kg	Vandenberg, SLC-6	Success
6	29 June 2012	Orion 8 / Mentor 6 (USA-237 / NROL-15)	Classified	Cape Canaveral, SLC-37B	Success
7	28 August 2013	KH-11 Kennen 16 (USA-245 / NROL-65)	<17000 kg	Vandenberg, SLC-6	Success
8	5 December 2014	Orion capsule Exploration Flight Test-1 (EFT-1)	21,000 kilograms (46,000 lb)[15][lower-alpha 2]	Cape Canaveral, SLC-37B	Success
9	11 June 2016	Orion 9 / Mentor 7 (USA-268 / NROL-37)	Classified	Cape Canaveral, SLC-37B	Success
10	12 August 2018	Parker Solar Probe[lower-alpha 3]	685 kg	Cape Canaveral, SLC-37B	Success
11	19 January 2019	NROL-71	Classified	Vandenberg, SLC-6	Success

1. CBCs underperformed, lower orbit than planned
2. The officially reported mass of 21,000 kg includes the Launch Abort System (LAS) which did not reach orbit, but excludes the residual mass of the upper stage, which did reach orbit, likely offsetting the mass of the LAS.
3. Star 48BV upper stage

Upcoming launches

The following missions have been announced by the National Reconnaissance Office.[16][17] As of August 2020, these are the final five missions.[18]

For these missions including modifications, ULA has been awarded US$2.2 billion, or US$440 million per launch.[19]

Date (UTC)	Payload	Client	Launch site
26 August 2020, 05:50 UTC	NROL-44	NRO	Cape Canaveral, SLC-37B
October 2020	NROL-82	NRO	Vandenberg, SLC-6
H2 2022	NROL-91	NRO	Vandenberg, SLC-6
H2 2022	NROL-70	NRO	Cape Canaveral, SLC-37B
H2 2023	NROL-68	NRO	Cape Canaveral, SLC-37B

Comparable vehicles

Current:

• Long March 5 (geostationary transfer orbit)
• Long March 5B (low Earth orbit)
• Long March 7A (geostationary transfer orbit)
• Ariane 5
• Falcon Heavy
• Proton-M

Development:

• Angara A5
• New Glenn
• Vulcan

Retired or cancelled:

• Atlas V Heavy (proposed, never developed)
• Saturn IB (retired)
• Titan III (retired)
• Titan IV (retired)

See also

• Heavy-lift launch vehicle
• Comparison of orbital launch systems
• Comparison of orbital rocket engines
• Comparison of space station cargo vehicles
• National Launch System, (1991–1993) study

References

1. "ULA CEO Tory Bruno". Twitter. Retrieved 12 February 2018. Delta IV Heavy goes for about $350M. That's current and future, after the retirement of both Delta IV Medium and Delta II.
2. "Delta IV Heavy". Spaceflight 101. Retrieved 26 July 2014.
3. "Delta IV Payload Planner's Guide, June 2013" (PDF). United Launch Alliance. Archived from the original (PDF) on 10 July 2014. Retrieved 26 July 2014.
4. "Mission Status Center". SpaceflightNow. Retrieved 26 July 2014. The ULA Delta 4-Heavy is currently the world's largest rocket, providing the nation with reliable, proven, heavy lift capability for our country's national security payloads from both the east and west coasts.
5. "Falcon Heavy, SpaceX's Big New Rocket, Succeeds in Its First Test Launch". NYTimes. Retrieved 6 February 2018. The Falcon Heavy is capable of lifting 140,000 pounds to low-Earth orbit, more than any other rocket today.
6. "Boeing Delta IV Heavy Achieves Major Test Objectives in First Flight" Archived 2012-04-19 at the Wayback Machine, Boeing, 2004, accessed March 22, 2012.
7. "Delta IV Heavy: Powerful Launch Vehicle". Space.com. Retrieved 21 July 2018.
8. "Delta 4-Heavy investigation identifies rocket's problem". Spaceflight Now. Retrieved 26 July 2014.
9. Bergin, Chris (18 January 2012). "EFT-1 set to receive Spring, 2014 launch date after contract negotiations". NASASpaceFlight.com. Retrieved 21 July 2012.
10. "Second Stage Ignites as First Stage Falls Away".
11. "Delta IV Launch Services User's Guide" (PDF). United Launch Alliance. 14 October 2013. pp. 2–10, 5–3. Archived from the original (PDF) on 14 October 2013.
12. "Delta IV Data Sheet". Space Launch Report. Retrieved 26 July 2014.
13. Ray, Justin (7 December 2004). "The Heavy: Triple-sized Delta 4 rocket to debut". Spaceflight Now. Archived from the original on 11 December 2004. Retrieved 13 May 2014.
14. Krebs, Gunter. "Delta-4". Gunter's Space Page. Retrieved 15 March 2018.
15. "NASA Orion Exploration Flight Test-1 PRESS KIT" (PDF). NASA. December 2014. p. 12. This article incorporates text from this source, which is in the public domain.
16. Ray, Justin (7 June 2016). "Surveillance satellite launching Thursday atop Delta 4-Heavy rocket". Spaceflight Now.
17. http://www.sworld.com.au/steven/space/usmil-man.txt
18. Henry, Caleb (21 August 2019). "ULA's Delta 4 Heavy down to final five missions". SpaceNews.
19. "Air Force awards ULA $1.18 billion contract to complete five Delta 4 Heavy NRO missions". SpaceNews.com. 30 September 2019. Retrieved 3 June 2020.

External links

• Delta IV Booster Integration Another Step Toward First Orion Flight