Delta IV

Delta IV
Delta IV Medium launch carrying DSCS III-B6.
FunctionOrbital launch vehicle
ManufacturerUnited Launch Alliance
Country of originUnited States
Cost per launchUS$164+ million[1]
Size
Height63–70.7 m (207–232 ft)
Diameter5.1 m (17 ft)
Mass249,500–733,400 kg (550,100–1,616,900 lb)
Stages2
Capacity
Payload to LEO
Altitude407 km (253 mi)
Orbital inclination51.6°
Mass11,470–28,790 kg (25,290–63,470 lb)[2]
Payload to GTO
Mass4,440–14,220 kg (9,790–31,350 lb)
Associated rockets
FamilyDelta (rocket family)
Comparable
Launch history
StatusRetired
Launch sites
  • Cape Canaveral, SLC-37
  • Vandenberg, SLC-6
Total launches
  •     Medium: 3
  •     M+ (4,2): 15
  •     M+ (5,2): 3
  •     M+ (5,4): 8
  •     Heavy: 16
Success(es)
44
  •     Medium: 3
  •     M+ (4,2): 15
  •     M+ (5,2): 3
  •     M+ (5,4): 8
  •     Heavy: 15
Partial failure(s)1 (Heavy Demo)
First flight
  • Medium: November 20, 2002 (Eutelsat W5)
  • Heavy: December 21, 2004 (USA-181)
Last flight
  • Medium: August 22, 2019 (USA-293/GPS III-2)
  • Heavy: April 9, 2024 (NROL-70)
Carries passengers or cargo
Boosters (Medium+) – GEM 60
No. boosters2[a] or 4[b]
Height13.2 m (518 in)
Diameter1.5 m (60 in)
Empty mass3,721 kg (8,203 lb)
Gross mass33,650 kg (74,185 lb)
Propellant mass29,698 kg (65,472 lb)
Maximum thrust879 kN (197,500 lbf)
Specific impulseSL: 245 s (2.40 km/s)
Burn time90.8 seconds
PropellantAP / HTPB / Al
First stage – CBC
Height40.8 m (134 ft)
Diameter5.1 m (17 ft)
Empty mass26,760 kg (59,000 lb)
Gross mass226,400 kg (499,100 lb)
Powered by1 × RS-68
Maximum thrustSL: 3,140 kN (705,000 lbf)
Specific impulseSL: 360 s (3.5 km/s)
vac: 412 s (4.04 km/s)
Burn time
  • 246 seconds (Medium core/Heavy booster)
  • 334 seconds (Heavy core)[2]
PropellantLH2 / LOX
Second stage – DCSS
Height12 m (39 ft)
Diameter
  • 4 m: 4 m (13 ft)
  • 5 m: 5.1 m (17 ft)
Empty mass
  • 4 m: 2,850 kg (6,280 lb)
  • 5 m: 3,490 kg (7,690 lb)
Gross mass
  • 4 m: 24,170 kg (53,290 lb)
  • 5 m: 30,710 kg (67,700 lb)
Powered by1 × RL10-B-2
Maximum thrust110 kN (25,000 lbf)
Specific impulse462 s (4.53 km/s)
Burn time
  • 4 m: 850 seconds
  • 5 m: 1,125 seconds
PropellantLH2 / LOX

Delta IV was a group of five expendable launch systems in the Delta rocket family. It flew 45 missions from 2002 to 2024. Originally designed by Boeing's Defense, Space and Security division for the Evolved Expendable Launch Vehicle (EELV) program, the Delta IV became a United Launch Alliance (ULA) product in 2006. The Delta IV was primarily a launch vehicle for military payloads for the United States Air Force (USAF), but was also used to launch a number of United States government non-military payloads and a single commercial satellite.

The Delta IV had two main versions, which allowed the family to cover a range of payload sizes and masses: Medium, which had four configurations, and Heavy. The final flight of a Medium configuration occurred in 2019. The final flight of Heavy was in April 2024.

Delta IV vehicles were built in the ULA facility in Decatur, Alabama.[5] Final assembly was completed at the launch site by ULA: at the horizontal integration facility for launches from SLC-37B at Cape Canaveral in Florida and in a similar facility for launches from SLC-6 at Vandenberg in California.

  1. ^ "Surplus Missile Motors: Sale Price Drives Potential Effects on DOD and Commercial Launch Providers".
  2. ^ a b Cite error: The named reference :1 was invoked but never defined (see the help page).
  3. ^ Kyle, Ed. "Delta IV Launch Record". Space Launch Report. Archived from the original on April 25, 2022. Retrieved January 21, 2023.
  4. ^ Graham, William (September 24, 2022). "Last West Coast Delta IV Heavy launches with NROL-91". NASASpaceFlight. Retrieved September 25, 2022.
  5. ^ "Boeing and Lockheed Martin Complete United Launch Alliance Transaction" (Press release). Boeing. December 1, 2006. Archived from the original on May 2, 2013.


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