Delta IV



The Nation’s Heavy Lifter

  • 15+ years of 100% mission success, founded on nearly 60 years of launch experience.

  • Proven heavy lift capability to deliver high-priority U.S. Air Force, National Reconnaissance Office and NASA payloads to orbit.

  • Design simplicity, manufacturing efficiency and streamlined mission and vehicle integration.

  • ULA Delta IV launches

  • Delta IV Photos



The Delta IV launch system is available in three configurations: the Delta IV Medium+, with two or four solid rocket motors (SRMs), and the Delta IV Heavy. Each configuration is comprised of a common booster core (CBC), a cryogenic upper stage and a 5-meter-diameter payload fairing (PLF).

The Delta IV Heavy employs two additional CBCs as liquid rocket boosters to augment the first-stage CBC.



Optimal orbit for each customer, delivering industry best spacecraft orbital insertion accuracy.













1,840 kg

4,060 lbs

5,080 kg

11,200 lbs

11,060 kg

24,380 lbs

9,610 kg

21,180 lbs

10,220 kg

22,530 lbs


2,710 kg

5,970 lbs

6,890 kg

15,190 lbs

13,730 kg

30,250 lbs

11,600 kg

25,580 lbs

12,830 kg

28,270 lbs


6,580 kg

14,500 lbs

14,210 kg

31,330 lbs

28,370 kg

62,540 lbs

23,560 kg

51,950 lbs

25,980 kg

57,280 lbs

GEO (Geosynchronous Orbit)=35,786 km Circular at 0 deg

GTO (Geosynchronous Transfer Orbit)=35,786 km x 185 km at 27.0 deg
LEO (Low Earth Orbit-Reference) =200 km circular at 28.7 deg or 90 deg

LEO ISS (Low Earth Orbit-International Space Station) =407 km circular at 51.6 deg

Payload Fairings

The payload fairing (PLF) provides a controlled, safe environment for spacecraft during ascent.

All ULA PLFs are configured for off-pad payload encapsulation, which enhances payload safety and security and minimizes on-pad time.

Delta IV offers a 5-meter-diameter PLF, optimized for the configuration and mission need. The Delta IV Medium uses a standard carbon composite bisector design. The Delta IV Heavy is available with an elongated carbon-composite bisector or metallic trisector PLF.



Main Engine

Design simplicity and demonstrated capability define the Delta IV RS-68A main engine. Designed and manufactured by Aerojet Rocketdyne, the throttleable RS-68A engine is the largest existing hydrogen-burning engine. Conceived using a simplified design approach, it has fewer parts, is lower risk and has inherently reliable operation.

  • Nominal Thrust (sea level): 702,000 lbs

  • Specifc Impulse (sea level): 362 seconds

  • Length: 204 in

  • Weight: 14,876 lbs

  • Fuel/Oxidizer: Liquid Hydrogen/Liquid Oxygen

Solid Rocket Motors

For additional thrust at liftoff, the Delta IV Medium+ uses either two or four Northrop Grumman solid rocket motors (SRMs). The SRMs are strapped to the common booster core and jettisoned in-flight for maximum performance.

  • Peak Vacuum Thrust: 280,000 lbf

  • Specific Impulse: 275.2 seconds

  • Length: 636 in

  • Weight: 74,500 lbs

  • Nominal Burn Time: 90 seconds

Upper Stage

Both the Atlas V and the Delta IV rely on the RL10 propulsion system to power their second stages. Logging an impressive record of nearly 400 successful flights and nearly 700 firings in space, RL10 engines, manufactured by Aerojet Rocketdyne, harness the power of high-energy liquid hydrogen. The RL10 boasts a precision control system and restart capability to accurately place payloads into orbit.

The Delta IV employs the RL10B with the world’s largest carbon-carbon extendible nozzle for increased performance.

  • Nominal Thrust: 24,750 lbs

  • Specifc Impulse: 465.5 seconds

  • Fuel/Oxidizer: Liquid Hydrogen/Liquid Oxygen

  • Length: 86.5 in (stowed); 163.5 in (deployed)

  • Diameter (nozzle extension): 84.5 in

  • Weight: 664 lbs

Atlas V

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Vulcan Centaur

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Delta II

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