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Musk Announces Return-to-Flight Date For Falcon 9 Rocket
Rei writes: After being grounded for six months after a strut failure doomed the launch vehicle, Elon Musk has confirmed rumors that SpaceX plans to try for launch again on December 19th, with a static test firing on December 16th. SpaceX will also attempt a landing of their first stage — not at sea, but on land. Lastly, this will be the first launch of a Falcon 9 "Full Thrust" variant, where the propellants are supercooled (with the oxygen just above its freezing point) to increase their density and thus fuel flow and thrust.
Aren't supercooled materials actually cooled below their freezing point, but kept in a liquid state? Oxygen "just above its freezing point" is damned cold, but not supercooled. So, which one is it?
Turnaround is much easier when the stage is nearly empty. First off you have air resistance killing off part of your lateral momentum for you, and you already have altitude. Your stage is vastly lighter as well, having used up most of its propellant and separated from the second stage and payload. Your last kilogram of propellant delivers about 23 times more delta-V than your first (in a way it's kind of problematic - even with just one engine operating and throttled all the way down (70%) it can't "hover", it still has way too much thrust). So turnaround is actually quite doable, if you have a little margin left over. It depends on how heavy your payload is and what sort of trajectory it's being launched to.
Nothing says 'welcome to the neighborhood' like a gunny sack full of dead squirrels.
Launch Complex 13 was leased to SpaceX and has been renamed Landing Complex 1.
It might be because the Atlas flies on Russian RD-180 engines? If the entire manned space program ended up depending on the continued goodwill of the Russians; well it would be sort of embarrassing at that point.
It makes you wonder why they don't always spend 2 1/2 times more per launch? Really, that's something you don't understand?
Atlas is the 7th generation of a rocket family that's been around since 1957. One would hope that they'd have gotten most of the kinks by now. By comparison, Falcon 9 is a 2nd generation of a rocket family that's been around since 2006.
Nothing says 'welcome to the neighborhood' like a gunny sack full of dead squirrels.
Unlike during the last Falcon 9 launch, I hope that they don't get impatient and turn on time warp again - everyone knows that it makes the physics unstable.
Nothing says 'welcome to the neighborhood' like a gunny sack full of dead squirrels.
SpaceX has a number of launches coming up according to Space Flight Now including:
* 19 Dec - Falcon 9 rocket will launch 11 second-generation Orbcomm communications satellites.
* Dec ? - Falcon 9 rocket will launch the SES 9 communications satellite.
* Jan - Falcon 9 rocket will launch the 10th Dragon spacecraft on the eighth operational cargo delivery mission to the International Space Station.
* Jan - Falcon 9 rocket will launch the Jason 3 ocean altimetry mission. Jason 3 will measure ocean surface topography to aid in ocean circulation and climate change research for NOAA, EUMETSAT, NASA and the French space agency, CNES.
* There are others scheduled for early 2016
Today's vices may be tomorrow's virtues.
Again: "Atlas is the 7th generation of a rocket family that's been around since 1957. One would hope that they'd have gotten most of the kinks by now. By comparison, Falcon 9 is a 2nd generation of a rocket family that's been around since 2006." Not sure how you missed that part. When the Atlas family was 9 years old, it was still undergoing regular failures. Atlas LV-3A, which was used from 1960 to 1968 (and would thus be the development-time equivalent of the Falcon 9) had 49 launches and 38 successes, or a success rate of only 77%.
Now, of course, that was a different time. The had less knowledge and technology base... although contrariwise they had far larger inflation-adjusted budgets. But let's just say that the technology issue means that Falcon 9 should prove itself much faster than the Atlas family did. Okay, so maybe the comparable level is to how Atlas was performing in the 1970s? The two Atlas rockets active in the 1970s (Atlas SLV-3C and Atlas SLV-3D) had a success rate of 84%. Okay, let's say the 1980s. The Atlas SLV-3D extended into the 80s, and there was also the atlas G, with a 67% success rate. It wasn't until the 1990s that they got up to a nearly 95% success rate - decades after the creation of the family.
You want perfection in under a decade of the creation of a new orbital rocket family. Please point me to a single case where that's happened, with a statistically significant number of launches under their belt. Proton? Nope. Soyuz? Nope. Delta? Nope. Arianne? Nope.
Nothing says 'welcome to the neighborhood' like a gunny sack full of dead squirrels.