Boeing Unveils Delta 4 Variants

Boeing has unveiled three commercial derivatives of its new Delta IV family of launch vehicles. “The commercial satellite industry is demanding reliable and affordable access to space — in greater volume than ever before,” said James F. Albaugh, president of Boeing Space & Communications Group. “Our three Delta IV Medium versions are key elements in our response to these demands.”

Known collectively as the Delta IV Medium-plus, the three new vehicles will retain the efficient, cost-effective modular design of the entire Delta IV fleet through the use of the Delta IV “common booster core.” Booster cores are 38 meters long and 5 meters in diameter — roughly the size of a Boeing wide-body airplane.

The Delta IV fleet is designed to offer both commercial and government customers a wide range of payload capability. For missions to geosynchronous transfer orbit (GTO), the range extends from 2.2 metric tons (Delta IV Small) through 13.2 metric tons (Delta IV Heavy).

The Medium-plus versions are distinguished by the number of Alliant
Techsystems-built solid rocket motors attached to the booster core and the
size of the upper stages and payload fairings, which protect the
satellites during the early ascent phases of flight.

“The three configurations of the Delta IV Medium-plus have been designed
to give our commercial customers flexibility over a wide range of payload
weights, coupled to the cost effectiveness of the modular design,” reports
Gale Schluter, vice president and general manager of Expendable Launch
Systems, the Boeing business segment responsible for developing, marketing
and flying the Delta fleet.

Members of the Delta IV Medium-plus family are:

• Delta IV Medium-plus (4,2) with two solid rocket motors and a 4-meter
  fairing for a GTO payload of 5.8 metric tons.

• Delta IV Medium-plus (5,2) with two solid rocket motors and a 5-meter
  fairing for a GTO payload of 4.7 metric tons.

• Delta IV Medium-plus (5,4) with four solid rocket motors and a
  5-meter fairing for a GTO payload of 6.7 metric tons.

All Delta IV variants are powered by the RS-68 rocket engine, designed and
built by the Rocketdyne Propulsion & Power unit of Boeing. Using
state-of-the-art automated tools, the RS-68 incorporates significant
reductions in parts count and touch labor, leading to substantial cost
savings.

Delta IV launch vehicles are evolved from the Delta family of rockets
which has been lifting satellites into orbit since 1960.

The Delta IV production team includes: Aerojet, Sacramento, Calif.,
second-stage engine for the Delta IV Small; Alliant Techsystems, Magna,
Utah, solid rocket motors for the Delta IV Medium-plus versions; Allied
Signal Aerospace, Teterboro, N.J., Redundant Inertial Flight Control
Assembly for guidance control of all Delta IVs; Pratt & Whitney, West Palm
Beach, Fla., second-stage engines for the Delta IV Medium and Heavy
versions; and Raytheon Engineers and Constructors, design and construction
of Delta IV launch facilities.