The five engine, single tank first stage configuration meant that the Falcon V was the first American launch vehicle since the Saturn V to offer true engine out reliability. Depending on the phase of flight, the first stage could lose as many as three engines and still complete its mission. The primary structure was made of a space grade aluminum alloy in a patent pending graduated monocoque, common bulkhead, flight pressure stabilized architecture developed by SpaceX. The design was a blend between a fully pressure stabilized design, such as Atlas II, and a heavier isogrid design, such as Delta II. SpaceX claimed to have captured the mass efficiency of pressure stabilization, but avoided the ground handling difficulties of a structure unable to support its own weight. After engine start, Falcon would be held down until all vehicle systems were verified to be functioning normally before release for liftoff. Helium tank pressurization was provided by composite over-wrapped inconel tanks from Arde Corporation, the same model used in Boeing's Delta IV rocket. Stage separation occured via dual initiated separation bolts and a pneumatic pusher system. All components were space qualified and have flown before on other launch vehicles.
The first stage returned by parachute to a water landing, where it would be picked up by ship in a procedure similar to that of the Space Shuttle solid rocket boosters. The parachute recovery system was built for SpaceX by Irvin Parachute Corporation, who also built the Shuttle booster recovery system. After refurbishment, the stage would be reused.
The second stage tank structure was made of aluminum-lithium alloy. SpaceX found this to be the lowest total system mass in this application of any material examined, including liquid oxygen compatible super-alloys and composites. A single SpaceX Kestrel pressure-fed engine powered the Falcon I upper stage. For added reliability of restart, the engine had dual redundant torch igniters. Helium pressurization was again provided by composite over wrapped inconel tanks from Arde. The helium was also used in cold gas thrusters for attitude control and propellant settling when a restart was needed. Provided that there was sufficient mission mass margin to accommodate increased gravity losses, the Falcon V upper stage can complete its mission even if only one engine is operative. In that case, helium cold gas thrusters would provide roll control.
The original narrower-tank design was updated by 2006. The Falcon V was now simply a Falcon 9 with four of the engines pulled and a partial propellant load.
LEO Payload: 4,200 kg (9,200 lb) to a 200 km orbit at 28.00 degrees. Payload: 1,250 kg (2,750 lb) to a GTO, 9 deg. Launch Price $: 12.000 million in 2004 dollars. Boost Propulsion: Lox/Kerosene. Cruise Thrust: 66.600 kN (14,972 lbf). Cruise Thrust: 6,800 kgf. Cruise engine: Kestrel. Initial Operational Capability: 2011.
Gross mass: 129,700 kg (285,900 lb).
Payload: 4,200 kg (9,200 lb).
Height: 29.00 m (95.00 ft).
Diameter: 3.40 m (11.10 ft).
Span: 3.40 m (11.10 ft).
Thrust: 1,590.00 kN (357,440 lbf).
Apogee: 200 km (120 mi).