Since November 2002, rockets from the Delta 4 Medium family have been launched 29 times, all of which were successful. Its last flight was with a 3rd generation

GPS The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...

satellite in August 2019.

About the Delta 4 Medium

The Delta 4 Medium (also referred to as 'single stick') was available in four configurations: Medium, Medium+ (4,2), Medium+ (5,2), and Medium+ (5,4). The Delta 4 Medium (Delta 9040) was the most basic Delta IV. It featured a single CBC and a modified Delta 3 second stage, with 4-meter liquid hydrogen and liquid oxygen tanks (called a

Delta Cryogenic Second Stage The Delta Cryogenic Second Stage (DCSS) is a family of cryogenic rocket stages used on the Delta III and Delta IV rockets, and on the Space Launch System Block 1. The stage consists of a cylindrical liquid hydrogen (LH2) tank structurally separate ...

(DCSS)) and a 4-meter

payload fairing A payload fairing is a nose cone used to protect a spacecraft payload against the impact of dynamic pressure and aerodynamic heating during launch through an atmosphere. An additional function on some flights is to maintain the cleanroom environm ...

. The Delta 4 Medium was capable of launching 4,200 kg to

geostationary transfer orbit A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit. Satellite, Satellites that are destined for geosynchronous orbit, geosynchronous (GSO) or geostationary orbit (GEO) are (almost) always put into ...

(GTO). From Cape Canaveral, GTO is 1804 m/s away from GEO. The mass of fairing and payload attach fittings have been subtracted from the gross performance. The Delta 4 Medium+ (4,2) (Delta 9240) had the same CBC and DCSS as the Medium, but with the addition of two

Orbital ATK Northrop Grumman Innovation Systems (NGIS) was a sector (business segment) of Northrop Grumman from 2018 through 2019. It was formed from Orbital ATK Inc. a company which resulted from the merger of Orbital Sciences Corporation and parts of Alli ...

-built 1.5-m (60-in) diameter

solid rocket booster A solid rocket booster (SRB) is a large solid propellant motor used to provide thrust in spacecraft launches from initial launch through the first ascent. Many launch vehicles, including the Atlas V, SLS and space shuttle, have used SRBs to give ...

Graphite-Epoxy Motor The Graphite-Epoxy Motor (GEM) is a family of solid rocket boosters first developed in the late 1980s and used from 1990 to the present day. GEM motors are manufactured with carbon-fibre-reinforced polymer casings and a fuel consisting of HTPB-b ...

s (GEM-60s)

strap-on booster A booster rocket (or engine) is either the first stage of a multistage launch vehicle, or else a shorter-burning rocket used in parallel with longer-burning sustainer rockets to augment the space vehicle's takeoff thrust and payload capability ...

s to increase payload capacity to 6,150 kg to GTO. The Delta 4 Medium+ (5,2) (Delta 9250) was similar to the Medium+ (4,2), but had a 5-m–diameter DCSS and payload fairing for larger payloads. Because of the extra weight of the larger payload fairing and second stage, the Medium+ (5,2) could launch 5,072 kg to GTO. The Delta 4 Medium+ (5,4) (Delta 9450) was similar to the Medium+ (5,2), but used four GEM-60s instead of two, enabling it to lift 6,882 kg to GTO. To encapsulate the satellite payload, a variety of different

s were available. A stretched Delta III 4-meter diameter composite

was used on 4-meter Medium versions, while an enlarged, 5-meter diameter composite fairing was used on 5-meter Medium versions. The Medium (4,2) version last flew on 22 August 2019, marking the retirement of the Delta 4 Medium variants.

Launch Statistics

Rocket configurations

Launch Outcomes

Launch sites

Orbits

Customers

Launch History

References

{{DEFAULTSORT:Delta IV Lists of Delta launches United Launch Alliance Lists of rocket launches