tag:blogger.com,1999:blog-1592992209402300549.post3141631749483883646..comments2024-03-29T09:08:47.702-04:00Comments on The Silicon Graybeard: A Fitting Day for Artemis to ReturnSiGraybeardhttp://www.blogger.com/profile/00280583031339062059noreply@blogger.comBlogger15125tag:blogger.com,1999:blog-1592992209402300549.post-64720924848379955062022-12-16T12:29:02.470-05:002022-12-16T12:29:02.470-05:00Somehow, they haven't offered me that one yet....Somehow, they haven't offered me that one yet. Now I gotta go find it!<br />SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-7139577985869220302022-12-16T12:27:06.336-05:002022-12-16T12:27:06.336-05:00Have you seen the video making the rounds of the A...Have you seen the video making the rounds of the Artemis launch synched up to Freebird? Can not stop smiling watching it. <br /><br />Back to the topic a fitting day indeed. Bad Dancernoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-56789632536562841352022-12-14T10:32:49.237-05:002022-12-14T10:32:49.237-05:00I find it funny that it took 50 years for the Hidd...I find it funny that it took 50 years for the Hidden Figures cast to put a duplicate empty capsule around the moon and skip atmosphere for the first time ever after forgetting all the manufacturing and engineering of that time just because.<br /><br />Almost as funny as the competition to make the most realistic phallic lift platform. That is a slap in the face, the landing is a teabag.MN Steelnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-3490262877333238112022-12-13T01:19:13.339-05:002022-12-13T01:19:13.339-05:00An inflatable ballute was designed in '66 or &...An inflatable ballute was designed in '66 or '67 as a way to recover the engine portion of the Saturn V 1st stage. Previously an inflatable ballute was designed as a one-man lifeboat for the Apollo program, where the astronaut would ride inside the shield as it reentered, and was equipped with parachutes, inflatable raft, survival kit and radio/radio transpoder.<br /><br />Very not new, even by the 70's.Beanshttps://www.blogger.com/profile/15293778848879361153noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-67225144787134664662022-12-12T19:09:46.724-05:002022-12-12T19:09:46.724-05:00No idea, but hope springs eternal; I ordered a rot...No idea, but hope springs eternal; I ordered a rotating Mars globe with the thought that my grandkid might be inspired.Roberthttps://www.blogger.com/profile/09800106790176447938noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-80462726498248663772022-12-12T15:40:42.071-05:002022-12-12T15:40:42.071-05:00In the 1930's in Germany, Doc Sanger did the M... In the 1930's in Germany, Doc Sanger did the Math for an Intercontinental Rocket Bomber, that Launched out of Germany, could Hit a West (U.S.) Coast Target, Skip, and Land at a Base in Japan, then be Turned Around to Bomb the East Coast and return to a Luftwaffle Base. (this, well before the War started.)<br />The BETTER Space Shuttle (designed by German Rocket Scientists, before the bureaucracy Ruined the Project) was a pair of true Rocket-Planes, one a Carrier and the other an Orbiter, that would perform this Maneuver to Launch, Recover the Carrier, and then the Orbiter. This design built on the Work of the X-15 and other Experimental Planes. They would have been Constructed of Nickel Alloys and Titanium, and the Orbiter had Hinged Wings for Low-Speed Landings.<br /><br /> Instead we got the Aluminum Tub with Bathroom Tiles glued on with Bathtub Sealer, and Shot into Orbit with Fireworks.<br />"Place on Ground, Light Fuse, Get Away." All sorts of convoluted bureaucratic conniptions were done to justify Solid- Fuel Rockets as Manned-Vehicle Primary Propulsion - where up until then, Fireworks were Only used for Emergency Systems, or in a few cases, as Boosters for specific Military Aircraft. we all saw how well that worked. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-54322614057805948562022-12-12T10:08:33.612-05:002022-12-12T10:08:33.612-05:00I don't have any more specific insight on it t...I don't have any more specific insight on it than you do, just my experience as an engineer. As you say, using the attitude thrusters to change the angle of the dished heatshield is the only real control they have. But I do know that this is a VERY tight "window" to achieve the right trajectory, and I cannot but believe that our guidance system and thruster control is far superior to what we had in Apollo.<br /><br />And we most certainly have better aero simulations around which to design control strategies. We couldn't do good hydrodynamic sims in the 70s.Malatropehttps://www.blogger.com/profile/12187333180472067677noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-59298501103450664382022-12-12T10:00:27.713-05:002022-12-12T10:00:27.713-05:00Want to start a pool on whether Artemis gets to th...Want to start a pool on whether Artemis gets to the moon or the US collapses first? Too close for me to call! SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-38995581543303807342022-12-12T09:55:45.632-05:002022-12-12T09:55:45.632-05:00Do they use thrusters to change the angle and skip...Do they use thrusters to change the angle and skip back out? Seems they'd have to, but I don't have a feel for how big a control surface would need to be.SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-86891088206993906242022-12-12T09:35:25.127-05:002022-12-12T09:35:25.127-05:00It appears that the "degree of skip" dep...It appears that the "degree of skip" depends on the amount of velocity lost on the first dive. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-70473538430238663902022-12-12T09:32:58.118-05:002022-12-12T09:32:58.118-05:00I would suspect that we didn't have the precis...I would suspect that we didn't have the precise trajectory control then that we do now, as the reason that skipping is feasible this time. Nor the automation in action during the loss of telemetry.Malatropehttps://www.blogger.com/profile/12187333180472067677noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-78355585257587795562022-12-12T00:10:29.057-05:002022-12-12T00:10:29.057-05:00Glad it worked, but I'm a bit skeptical that A...Glad it worked, but I'm a bit skeptical that Artemis will ever put folks on the Moon. I hope I'm wrong.John Wilderhttps://wilderwealthywise.comnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-68729996304968937722022-12-12T00:05:31.201-05:002022-12-12T00:05:31.201-05:00Apollo adjusted it's attitude during reentry u...Apollo adjusted it's attitude during reentry using it's thrusters. It didn't do a full skip back out of the atmosphere, but it did regain some altitude on purpose during reentry to let some of the heat dissipate. Since it wasn't planned for, a full skip back out could have had dire consequences.drjimhttps://www.blogger.com/profile/05647484115197408897noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-27357867692164500812022-12-11T22:51:39.459-05:002022-12-11T22:51:39.459-05:00To the best of my memory, Arthur C Clarke mentione...To the best of my memory, Arthur C Clarke mentioned this type of reentry in a fictional story (not 2010: Odyssey Two) sometime in the 70s. You might remember in that story the Leonov used an inflatable ballute for braking to enter Jupiter orbit. Clarke DID mention - somewhere - about essentially double tapping the atmosphere in his story for the reentry of a crewed vehicle. Well before that was considered a more or less fatal oops using the techniques available then.<br /><br />Great piece, thanks SiG.<br /><br />J F Pondernoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-36778957936803427252022-12-11T22:13:33.491-05:002022-12-11T22:13:33.491-05:00Thanks for the updateThanks for the updateLLhttps://www.blogger.com/profile/05538854359365988863noreply@blogger.com