DerekL1963

*sigh* Seriously, this nonsense needs to die in a fire. You don't need to shut down an SRB - all you need it to do is produce zero net thrust so it will be left behind. This is fairly straightforward to do - simply vent the case and the burn rate drops to essentially zero. If you can arrange for it to vent forward (at an angle so as to not to nail the departing payload), so much the better as it then acts as it's own retrorocket. And this is old, old tech - dating back at least to the 1950's. Polaris A-1, A-2, Poseidon, MM-I, -II, -III, and Peacekeeper all used or use this method. (As did the much smaller SUBROC and ASROC.) The Titan that would have lifted Dyna-Soar would have used this method. NASA considered it for the Shuttle, but abandoned it because the dynamic loads would have torn the ET part and thrown the Orbiter into the airstream where it would have been torn apart (exactly as happened to Challenger). The reason not to use solids for manned launches isn't that you can't get away from them in an emergency - it's because pretty much their only failure mode is an earth shattering (and very sudden) kaboom.

A friend who worked as engineer for NASA out at Dryden used to describe ejection seats thusly: "Attempting suicide to avoid certain death". I imagine LES systems are much the same thing.

Actually, it ended up that all the main parts (save two) of my mothership were +/- 10 tons of the first piece I lifted, so all that optimization time paid off - all the subsequent lifts were just modifications of that first lifter. Now all I have to do is design the biggest PITA (the tank farm used for fueling on orbit) and I'm ready to roll into orbital assembly. I've looked at variants of RSS, too much like work.

Partly. But also because the Falcon I was a dead end (the expected market never materialized) and using five and then nine of an existing design was faster and cheaper to market than starting over. Even then, it was a close race - at one point Musk was within hours of having to decide whether to throw Tesla or SpaceX overboard to give the other a chance of surviving... then the ISS resupply contracts came through. That being said, none of the N-1's problem's were directly connected with having that many engines. The main problem was getting KORD (the engine control system) functioning properly. Had they ever actually performed static testing on the Block A stage, they might have worked out the bugs.

Started designing the lifters for the various pieces of my Jool 5 mission... It's probably crazy that I spend an hour optimizing a booster that I'll only use once, but I can get obsessive about the details.

That presumes the launch vehicles are available, just sitting around for an urgent launch, which I highly doubt.

Well, now you're moving the goalposts, this is yet another new claim (and one that makes even less sense) when the holes are revealed in your previous one. That makes the presumption that a) the target bird is equipped for life extension (none are AFIAK), and B) that it doesn't take significant time to acquire a life extension bird, and c) doesn't take significant time to launch said bird. Take a look at Orbital ATK's current launch schedule and get back to me.

It's a huge relief for me, even though I live on the other side of the continent... Throw a dart at the Atlantic Seaboard from Miami to the Virginia Capes and the odds are it'll land near family or friends.

It just so happens that I watched Scott Manley fly a pretty small lander down to Tylo last night.

Kryten's point went over your head - the big constellation operators are unlikely to be interested in mission extension, because by the time the birds are ready for mission extension they're obsolescent. A cheap mission extension "saves" money, but it also means they make a lot less money because the new capacity they don't launch. Spending 180 million sounds cheaper than spending 260 million, but you're failing to take into account the difference in income between the two cases. (It's all about market share as well - demand for satellite communications is still growing, and not launching a newer more capable bird also means loosing out on new business.) The result isn't a short term gain in profit - it's a short (and long) term loss of profit.

KSP version 1.2 (which comes out Tuesday, the 11th) has a new stock science container which can basically hold an unlimited number of unique science reports. It's a .625 meter part and weighs basically nothing.

"Very close" != "Free return", either you are or you aren't - if 13 had been on a free return trajectory, they wouldn't have had to make a burn to get onto a free return trajectory. (Close only counts in horseshoes, hand grenades, and thermonuclear weapons. Not so much in orbital mechanics.) IIRC, their periapsis w/o getting back on free return was a couple of thousand miles up. Some of the confusion may come from the hybrid nature of the actual trajectory... At S-IVB burnout, they were on free-return but after T&D and extracting the LM they'd make a burn with the SPS and depart from free return. Apollo 13 made that burn at about 30:40 MET. http://history.nasa.gov/ap13fj/05day2-mcc2-tv.htm

Not all Apollo missions used a free return trajectory - less than half of them did, through Apollo 11. They stopped using free return from 12 onwards because it sharply limited landing site availability.

You asked for vehicles in a comm network, not for vehicles with science containers...

Hm.... Maybe you want to wait for 1.2 and the new science container?

If I'm playing in the evening, a nice Jack 'n coke. Rarely snacks.

First report from KSC: https://blogs.nasa.gov/kennedy/2016/10/08/aerial-survey-of-kennedy/ " After the initial inspection flight Saturday morning, it was determined that the center received some isolated roof damage, damaged support buildings, a few downed power lines, and limited water intrusion. " Full building-by-building inspection in work.

Yesterday and a bit of today so far actually. After landing on Bop and Pol, and then returning to Kerbin... The dress rehearsal for my Jool-5 is complete. There was a bit of drama in returning from Bop,but a quick trip out to refuel the lander made short work of that. Details here in my challenge log thread. Next up, going through my notes and updating the designs of the various vehicles, then after figuring out how to boost them into orbit assembly of the actual mission begins.

*Whew* At long last, the dress rehearsal is over. - Successfully landed on Bop. While the lander didn't have the d/v to return to the mothership, it could reach a stable circular orbit around Jool. I sent the T/TV out to refuel it and both returned to the mothership. - Successfully landed on Pol. The lander docked to the mothership with less than 3% of it's fuel remaining... If I'd decided to exercise the rescue option (as at Bop), there was enough LFO at the mothership and enough LF for the T/TV for a rescue mission. - Successfully returned to Kerbin. While a rescue option at Pol would have cut into the margin, the T/TV still should have been able to return to Kerbin. So while I've added the LF I boosted earlier in the dress rehersal to the mothership design, I don't think I need to add more. Monoprop was a bit dicey,but the dress rehearsal didn't have the monoprop left over from orbital assembly that the full mission would. LFO as designed should be sufficient. Next up, finish revising the design and start working towards orbital assembly!

That depends on your PC... and makes the journey ineligible for the Jool-5 challenge. Personally, I think the basic problem here is the whole scheme is too ambitious.

Another way to do this is to come in over the poles.

One could always hyperedit it into Laythe orbit in the sandbox and find out.

They're not completely useless - you just need to know how to use them. In this case, your burn time is too large a fraction of your initial orbital period - and there are two main solutions. Increase your t/w ratio by adding engines or lightening your vessel. (And make sure you're using fuel tanks, not LFO tanks. Otherwise you're hauling around a bunch of dead weight.) Or increase the altitude of your initial orbit so that burn time is a smaller fraction. (There is another - use a node splitter and make multiple burns,but I have little experience with them.)

Nah, build a spacedock. /stirringthepot

The latest from KSC: