|Two Falcon 9 engine arrangements. On the left, with a 3x3 rectangular or "tic-tac-toe" pattern is the original v 1.0 arrangement. On the right is the upgraded v1.1 arrangement, which utilizes what SpaceX calls an "octaweb". Photo c/o NASA Spaceflight.com.|
Space Exploration Technologies (SpaceX) seems publicly committed to the announced September 5th, 2013 launch date for the Canadian Space Agency (CSA) Cascade Smallsat and Ionospheric Polar Explorer (CASSIOPE) from Vandenburg Air Force Base.
|Falcon 9 first stage with new struts in launch configuration. Photo c/o the Daily Cos.|
But there are also a series of important, non-trivial modifications and upgrades to the SpaceX Falcon 9 rocket which are expected to be tested out for the first time during this particular flight and lots of work remains before the launch can proceed.
Chief among the upgrades are the replacement of Merlin 1-C engines with an equal number of substantially more powerful Merlin 1-D engines. These new engines boast an increased thrust (from 95,000 to 140,000 to lbf at sea level), the capability of throttling back and forth between 70-100 percent of overall power and, as described in the March 20th, 2013 NASA SpaceFlight.com article "Falcon 9 boost as Merlin 1D engine achieves major milestone," the use of improved manufacturing processes utilizing fewer parts and less labor to lower overall production costs.
The new engines are also designed to be reused, which makes sense given that the internal structure layout of the latest Falcon 9 allows for the attachment of four landing struts, which should enable the first stage (with a little help from the new throttle control) to land under its own power after use, in much the same way as the SpaceX Grasshopper.
Altogether, according to the August 11th, 2013 Commercial Space Watch article "Update on SpaceX activities," the September 5th launch will contain the following firsts:
- It will be the first launch with the upgraded Falcon 9 V1.1.
- It will be the first launch with the new Merlin 1-D engines, the first time with the new circular arrangement of the engines on the 1st stage booster, the first launch with fairings (to protect the payload satellite) and the first Falcon 9 launch with a satellite (the aforementioned 800 pound CASSIOPE) as the primary payload.
- It will be the first launch with the "stretched" stages. (The updated Falcon 9 is 16 m taller than before.)
- It will be the first launch at the new SpaceX Vandenberg launch facility, which has yet to be formally declared operational.
- It might also be the possible first test of a controlled return and hover above the ocean surface for the first stage booster.