Space Exploration Technologies
Falcon-9 is a liquid fueled orbital launch vehicle for
medium to heavy sized missions, which is developmened by SpaceX (Space Exploration
The first stage, which is potentially reusable after recovery by parachutes
(B1 --> v1.0) or by powered landing (v1.1), is powered by 9 of the SpaceX built
Merlin-1C (v1.0) or Merlin-1D (v1.1) engines with regenerative cooling. The
upper stage uses a single Merlin engine. The Falcon-9 fairing for satellites
is 3.10 x 5.20 m dimensioned.
The Falcon-9 will also lift the Dragon space capsule for ISS cargo flights,
which might be developed into a manned spacecraft.
The first flight for a Falcon-9 v1.0 took place in June 2010. In 2013, the enlarged
Falcon-9 v1.1 will take over, featuring higher powered Merlin-1D engines in
a new octagonal arrangement and larger tanks. A version of the Falcon-9 v1.1
with landing legs for recovering the first stage will be known as Falcon-9 v1.1R.
The initial Falcon-9 v1.1 flights will land in the ocean. Landing in the water
causes loss of the stage. The first landings on a barge was tried on the Dragon
CRS-5, DISVOVR and Dragon CRS-6 missions, but all failed.
The new Falcon-9 v1.2 (FT)
represents an evolved version of the Falcon-9 v1.1 incorporating a number of
performance enhancements to enable the launch vehicle to lift heavy satellites
to GTO while preserving the option of re-using the first stage. The launcher
represents the third evolutionary stage of the Falcon-9.
The most notable changes on the Falcon-9 v1.2 include the use of densified propellant
on both stages, a change in tank sizes, a slight stretch of the interstage and
second stage length, modifications in the thrust structure, weight-reduction
measures and the operation of the impoved Merlin-1D engines in both stages.
The Merlin 1D+ engine now delivers a sea level thrust of 756
kN, representing a 16% increase over the initial Merlin-1D version. In vacuum conditions,
the Merlin 1D+ engine delivers 825 kN of thrust. The improved Merlin 1D+ Vacuum
engine uses an extended nozzle design and achieves a thrust of 935 kN, representing
a 17% increase in thrust.
The Merlin-1D+ engine has an active throttling capability which allows Falcon 9
v1.2 to fly a more flexible mission profile. The previous Merlin engines has
not or no active throttle capability and the Falcon-9 had to shut two Merlin engines
down to limit stress on the vehicle as the launcher approached first stage cutoff.
The tank capacities has been increased by change of the propellant coolings. The
liquid oxygen will now be about 23°C colder than the boiling point. This results
in a density increase of about 9%. Also, the Kerosene is cooled slightly. By a temperature
of about -6°C, its density increases by about 2%.
In addition, the second stage is total of 5 feet longer, the interstage the half
Moreover, it was the first time decided not to shut down two engines of the first
stage. Therefore, the name FT (Full thrust)