Delta IV Heavy
It is similar to the Medium+ (5,2), except that it uses two additional Common Booster Cores instead of using Graphite-Epoxy Motors. These are strap-on boosters which are separated earlier in the flight than the center Common Booster Core. The Delta IV Heavy also features a stretched 5-meter composite payload fairing. An aluminum trisector (3 part) fairing derived from the Titan IV fairing is also available. The first launch in 2004 was a test launch only. Its first payload was the DSP-23 satellite.
Capacity of the Delta IV Heavy:
- Low Earth orbit (LEO) 27,569 kg (net 1221 kg 4293-5 payload attach fitting) 
- geosynchronous transfer orbit (GTO) 12,999 kg (1804 m/s to GEO; net 1221 kg 4293-5 payload attach fitting).
- geosynchronous orbit (GEO) 6,365 kg (net 385 kg 4394-5 payload attach fitting) 
- escape orbit 9,306 kg
- C3 performance of 30 km2s−2: 5,228 kg
- C3 performance of 60 km2s−2: 2,521 kg
The above capacities to LEO, GTO and GEO have had the mass of a payload attach fitting subtracted. An additional ~30 kg should be subtracted for the separation system to get the actual spacecraft mass capability. See  Section 5 for details.
The Heavy's total mass at launch is approximately 733,000 kg, much less than that of the Space Shuttle (2,040,000 kg), but is not reused.
- "Boeing Delta IV Heavy Achieves Major Test Objectives in First Flight", Boeing, 2004, accessed March 22, 2012
- "Delta Launch 310 – Delta IV Heavy Demo Media Kit - Delta Growth Options". Boeing.
- US Air Force - EELV Fact Sheets
- "Delta IV Launch Services User's Guide". United Launch Alliance. June 2013. pp. 2–10,5–3.
- Bergin, Chris (2012-01-18). "EFT-1 set to receive Spring, 2014 launch date after contract negotiations". NASASpaceFlight.com. Retrieved 21 July 2012.