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Falcon 9 performs another perfect soft landing – SpaceX now confident it can land back at the launch pad (video)

• By Sebastian Anthony on July 23, 2014 at 12:38 pm
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Following the tenth launch of a Falcon 9 rocket last week, SpaceX is reporting that the rocket’s first stage carried out a perfect soft landing back here on Earth in the Atlantic Ocean. This is the second time that SpaceX has successfully soft-landed a Falcon 9 rocket in the Atlantic Ocean and now Musk’s commercial space exploration company is confident enough that it can take the next, most important step: soft landing the Falcon 9 on a solid surface, so that it can be reused in future launches, instantly cutting down the cost of a space launch by tens of millions of dollars. If all goes to plan, SpaceX will attempt a soft landing on a solid surface in October, and then again in December.

As you may recall, SpaceX managed the first ever soft landing of an orbital booster back in April, following the successful launch of CRS-3 to the International Space Station. At the time, though, the video footage was massively corrupted, which meant SpaceX was unable to confirm what happened during the all-important last few seconds of powered descent (a fantastic crowdsourced effort managed to fix some of the video, but there’s still a lot of missing data). Now, as you can see in the video below, we finally have video footage to confirm that the Falcon 9 first stage booster landed slowly, gracefully, and perfectly vertically in the Atlantic Ocean. (The poor image quality is due to ice fouling on the lens; SpaceX is working on removing that for the next launch.)

As we mentioned earlier, this is the first time that an orbital booster has been soft-landed back on Earth; in all of humanity’s previous space launches, the rockets have simply fallen into the ocean, usually causing way too much structural damage to ever be reused (they are some of the most expensive expendables ever created by humankind). Why has no one ever attempted a soft landing before? Mostly because it’s really hard.

Watch the video below, which shows what happens to the two Space Shuttle Solid Rocket Boosters (SRBs) during launch, acceleration towards the edge of space, and then separation. The SRBs burn for around 127 seconds, propelling the Space Shuttle to an altitude of 28 miles (45 km) and 2,900 mph (~1,300 meters per second). The SRBs then begin their descent back through the Earth’s atmosphere and hit the Atlantic Ocean about 279 seconds after separation. The Falcon 9 first stage, because it has a longer burn of 180 seconds, is travelling at around 6,300 mph (Mach 10) and an altitude of 50 miles (80 km).

In the video, the SRBs use dumb parachutes to reduce their velocity. The Falcon 9 first stage, however, uses precise bursts of its Merlin 1D engines to bring both lateral and vertical velocity down to zero meters per second. Its extensible landing legs are deployed, and if all goes to plan a soft landing occurs.

How to maneuver a very long cylinder (such as a descending Falcon 9 rocket) with just a single point of thrust: Gimbals!

Now that two soft landings over water have been successful, SpaceX says the next step is to try it on a solid surface. SpaceX is being coy about what a “solid surface” is exactly, but it’s probably some kind of floating launch pad (barge) in the middle of the Atlantic Ocean. If the landing is successful, the Falcon 9 first stage will be shipped back to SpaceX for a quick refueling, and then it’s ready to fly again. (That’s the theory anyway; in practice I’m sure SpaceX will thoroughly check it out first.) The eventual goal is to fly both the first and second stage back to the launch complex at Cape Canaveral — but that probably won’t occur for another year or two.

SpaceX will attempt to land on a solid surface on flights 14 and 15 of the Falcon 9 rocket, which are scheduled for October and December 2014. Even if SpaceX only manages to reuse a first stage once, it would instantly cut the cost of a space launch by tens of millions of dollars — and a Falcon 9 is already the cheapest way to get stuff into space. If the first stage (and eventually the second stage) can be reused multiple times, we’ll very soon be looking at the dawn of cheap commercial space travel.