sevenperforce

Purely visual mods (reskins, etc.) are fine. I'm flying the boostback-and-RTLS "blind" myself, but I don't want to be too big a jerk so I'll say informational mods are okay too. Mechjeb for information is fine, but no use of autopilot.

Yeah, exactly what he said.

With the Falcon Heavy's first test fire just days away, Elon's personal Tesla already mounted to the PAF, and the launch to Mars expected next month, what better time than Christmas break to build a Falcon Heavy in KSP and use it to send a battery-powered sports car to Duna? The Challenge: Build a battery-powered two-seat rover (with a probe core, please; this IS a Tesla we're talking about), mount it on the single-engine upper stage of a three-stick parallel-staged launch vehicle, and send it to a Duna-intersecting orbit! Recover as many components of your launch vehicle as possible. All mods are allowed, but try to keep it as close to stock as you can, and name whatever mods you use. Scoring is based on accumulation of points as follows: Gone For a Spin (10 points): Before the launch, demonstrate your Roadster's moves by driving it around the KSC. Speed Demon (15 points): Test your Roadster at speeds over 100 mph (45 m/s). Falcon Nine (27 points): Use nine engines on each of your booster cores. Autonomic (13 points): Use drone cores; nothing manned. Looking Easy (16 points): Recover at least one parallel booster. Insane Mode (42 points): Recover both parallel boosters with boostback, RTLS (anywhere on KSC continent), and propulsive landing. Downrange (19 points): Recover your center core. Supercruise (18 points): Recover your center core by landing on a boat. Tru Lyfe (33 points): All booster recoveries without chutes. Hail Mary (28 points): Bring back the upper stage. Double Trouble (26 points): Build your own fairings and recover at least one. Purity (30 points): No mods. Destination (22 points): Land your Roadster on Duna and take it for a spin! Leaderboard: @Ultimate Steve: 277 points @LightBender: 196 points @sevenperforce: 190 points

I'm just saying, in the pictures the top is down. So putting the windows up won't exactly do much.

Windows?

IIRC it was planned for Dec 30.

Meanwhile, Mr. Steven is in port RIGHT NOW, probably being unloaded, and there are no port cams with a good view, and no one onsite to see. If I had any contacts at news orgs in LA I'd tell them to get down there.

TWR on the upper stage is pretty poor; it pulls away rather slowly. The plume gases are racing away from the MVac at 3400 m/s, so they rapidly envelop the first stage. Plus, you're seeing it from VERY far away, so distances are deceiving.

Cold-gas RCS puffs from the nitrogen thrusters on the first stage.

Stage 2 wasn't in a perfectly circular orbit, so each satellite was nudged in a slightly different direction, at a slightly different release speed. Thus, even though all the sats have essentially the same orbital period, they will slowly drift apart. And yes, they each have thrusters (hydrazine, probably) for station-keeping. All commercial sats have to be able to control themselves. These thrusters will be used to fix their orbits once they've all drifted into an essentially even distribution around the planet. In theory, they could have all been released simultaneously and used their thrusters to navigate to where they needed to be, but this would have increased the risk of collisions, and it would have meant that some of the sats used more fuel (and thus had lower orbital lifespans) than others. This way, they all reach their proper locations at about the same time, each with about the same expenditure of fuel. Note that while GEO comsats typically need very little station-keeping fuel, they still need an engine to circularize from GTO to GEO, and they also need enough dV to remove themselves into a high graveyard orbit at the end of their lives. In contrast, LEO comsats don't really need to circularize, and they don't need fuel for a terminal graveyard orbit insertion, but they do have a lot more station-keeping needs because of the higher drag in low orbit. It wasn't a different interstage; it was the same interstage as the one used on the first flight. They don't take the interstage off between flights. The simplest reason why they'd have fins on it was to guide it down precisely so that there was no risk to the fairing recovery boats/crews. They also probably used the opportunity to do some end-of-life destructive testing for varying entry regimes. They might have tried testing various failure modes, like landing on two engines instead of three and using gimbaling to compensate for thrust asymmetry. SpaceX is intentionally trying to avoid the Shuttle-style "recover and rebuild" approach to reusability. Elon believes that reuse isn't profitable unless it can be rapid, and recovering old engines to be rebuilt and installed elsewhere doesn't fit. Plus, then you'd end up with a booster that had a mixture of new engines and reused engines, meaning the lifetime of that booster would be tied to those engines rather than all the other brand-new hardware. And you'd potentially have engines with different thrust ratings. I can see them swapping reused engines in and out in future expendable launches, if a particular engine showed anomalies during the static fire. But they've recovered 20 boosters at this point so that's a stock of 180 engines they could choose from...

The key is that they chose to expend a reused booster. The main thing detractors say about SpaceX's reuse program is that it's all a gimmick: that Elon is just obsessed with reuse, that it's all a big waste of resources, that expendable rockets will always be more capable, more reliable, and ultimately more economical. Simply recovering a booster doesn't combat this idea, because you haven't shown that you can reuse it. Continuing to occasionally expend new rockets on high-energy missions doesn't, either. Even reflying used rockets could still be said to be just the pursuit of an idea, more trouble than it's worth, that sort of thing. But once the program has progressed so far that SpaceX decides to expend a reused booster, then it's obvious that A) reuse is working, and B) their decisions are being driven by business acumen and not just a crazy idea.

The Roadster is not going to intersect anything for a billion years or so.

Tons of conspiracy theorists waxing eloquent, including a surprising number of celebrities. You always have this idea that celebrities ought to be a LITTLE more aware than the general public, but noooooo. "Satellite?! I don't buy it. If it was a satellite they would have announced it ahead of time." Right.... Anyway, I was thinking...in a way, the notion of dumping a booster into the ocean on its second flight, even when it COULD be recovered, validates the economics of reuse. It's one thing to develop a massive system for recovering boosters, but recovery alone doesn't mean reuse is economical -- just look at the Space Shuttle. However, if reuse has progressed to the point that a business can make a profit-and-loss assessment where they decide to expend a reused booster, then OBVIOUSLY reuse is working, because those kinds of profit-and-loss decisions wouldn't be made if the goal was reuse for reuse's sake. Any news on the fairing recovery?

The SpaceX Flickr now has all full-res pics of the Roadster with flanking fairing halves. What recovery hardware can we spot? I already see cylindrical nitrogen tanks (which, for the record, look IDENTICAL to the KSP cylindrical monoprop tanks, albeit more grey). What else? I see some lines that look like they could be rigging for chutes. Any thrusters? Any chute packs?

Back in the early days of the space race, IIRC, there were two orbital launches about 80 seconds apart. But one of the launches was only reported to the minute, not to the second, so there is a 30-second-either-way uncertainty. Which means there is an 81.7% chance this is the shortest delay between two orbital launches ever, and an 18.3% chance that it is not.

Specifically, I spy a few nitrogen tanks for cold-gas attitude control. And maybe some of the rigging lines for the steerable parachute.

While my heart is stopped over the pictures of the Tesla..... .......look at the insides of the fairings! RECOVERY HARDWARE!

Going to be epic when we get to later FH missions and we have simultaneous footage of the ground cam, each of the side boosters headed back toward the launch site, the core booster plummeting toward the ASDS, the ASDS deck feed, the second stage powering up to orbit, cams from both fairings, AND fairing catch cams.

Mr. Steven left port late last night and is heading south at full speed.

No. The pusher bar in the interstage goes up inside the bell of the S2 engine and pushes against the throat.

They have that data from expendable entries.

You mean, reserve some extra propellant and then use it to boost the booster up to higher velocities? Not sure what that would provide.

If they wanted to just play around, they could bring the F9 down with a high lateral velocity, then do the "landing" burn effectively sideways, so it would already be almost all the way laid over at v=0. I don't know that it's actually tarped.

I'm not so sure. It may be that the interstage here is just really sooty from the last landing and so it looks grey but it's actually still the original Block 3 one.

Water landing means entry burn.