Landing an Orion capsule

[willpittenger]

That is still enough to make it tough for tourists to watch. The landing could readily happen behind a large hill. Out west, there are plenty of large hills. Portland, Oregon even has Mount Tabor within its city limits. It would have no problems hiding your landing. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[darkenfast]

The CEP is given in the ESAS report, and although I can't remember what it is, it's obvious that the dry (and flat) lakes at Moses and Edwards are big enough to serve as landing sites. If they allow the public to the perimeter (a big if), it should be quite easy to see, although given that the CEV is a lot more compact than the Orbiter, binoculars might be a good idea. <br />The idea that it's going to come down uncontrolled and way off the mark is just more "bashing". The lifting re-entry will be controlled to hit a spot over the site (which I'm sure will take into account the current winds), and will be no more risky than gliding down in an unpowered Orbiter, which has never missed a runway. Given the accuracy and the need for emergency landings in other sites (and on water), straight parachutes are probably a better bet than ram-air wings and the like.<br /><br />I'm curious to see what the air-bags (or retros) turn out to be. I've always liked the Mercury idea of the shield itself functioning as the base of a passive bag, hence avoiding a large object dropped over land.

 

[willpittenger]

You do have to remember that Carpenter was too distracted to do his job. He never should have flown (with perfect 20/10 hindsight). <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[baktothemoon]

"That was due to pilot error"<br /><br />Yeah, I remember reading that Kraft fried him to a crisp on return to KSC.

 

[Boris_Badenov]

WOW, 250 miles off. That sure would make a water landing difficult to retrieve for a Dragon capsule, & damned dangerous if it were over land.<br /><br />Working through a jammed flight plan and five onboard experiments, Carpenter helped among other things to identify the mysterious 'fire fly' particles of frozen liquid around the craft, first observed by John Glenn. Carpenter was the first American astronaut to eat solid food in space. A balky control stick, redesigned for later Mercury missions, meant that fuel consumption was a problem throughout his flight. A malfunctioning automatic control system, at retrofire, forced Carpenter to manually control his reentry; a misalignment in yaw and decelerating thrusters (another malfunction) resulted in a 250-mile overshoot. Carpenter was located in his life raft, safe and in good health, forty minutes after splashdown, and recovered by the USS Intrepid.<br />http://en.wikipedia.org/wiki/Scott_Carpenter<br /> <div class="Discussion_UserSignature"> <font color="#993300"><span class="body"><font size="2" color="#3366ff"><div align="center">. </div><div align="center">Never roll in the mud with a pig. You'll both get dirty & the pig likes it.</div></font></span></font> </div>

 

[willpittenger]

Ignore all that. Carpenter was too distracted by those fireflies to do anything else. (The fireflies where a low priority.) He used most of his fuel manuevering to examing the fireflies. Because of his distraction, he ignored attempts by Flight to get him to move towards manually firing those retro rockets. He missed not because he had to do it manually, but because he was late firing the retros. Plain and simple. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[baktothemoon]

"Carpenter helped among other things to identify the mysterious 'fire fly' particles of frozen liquid around the craft, first observed by John Glenn."<br /><br />Actually, Shepard saw them on his first flight. The fact that Carpenter was way off was because he was the most inexperienced pilot of the Mercury Seven, and stupid in general.

 

[MeteorWayne]

I don't think that the "stupid in general" comment is called for.<br />Maybe he screwed up and got his butt chewed out, but at that point there was no guarentee that you would even come back alive.<br />Give the guy a break. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[willpittenger]

You should have told Chris Kraft that back in the early 60's. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[MeteorWayne]

I would love to meet him.<br />That probably wouldn't be what I'd discuss.<br />I'd just say thank you for all that he has done to allow humans to explore space.<br />Without people like him (and even Scott), the moon might still be an unknown.<br />Yeah, we don't know everything, but all those humans risked their lives (or in CK's case, his sanity) to touch the moon, and bring pieces back so we could learn. They have an elevated place in the earth's history.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[halman]

darkenfast,<br /><br />Capsule re-entries are ballistic trajectories, with final landing point determined primarily by time and duration of retro rocket firing. The capsule has very limited terminal guidance, due in part to the nature of ablative heat sheilds. The capsule cannot be tipped very far off the axis of travel without exposing one edge of the heat sheild to the majority of the thermal effects. Tipping the capsule would require considerable propellent use, due to the cross-section of the body being about the same in all dimensions. Parachute control is nearly impossible, because the shrouds all tie into a single lifting cable. High altitude winds and changes in air density affect the trajectory, with unpredictable effects. This does not mean that the capsule will land hundreds of miles away from where it was intended, but it makes hitting a bulls-eye very difficult.<br /><br />Gliding down in an unpowered orbiter was always more risky than a ballistic entry, simply because there is so little to go wrong with a ballistic trajectory. Hitting a runway meant having terminal guidance capability all the way through the descent, either by firing thrusters or using air foils.<br /><br />Moses Lake, Washington is an area of sand dunes and shallow resivoirs, which is at least 100 miles from any major population center. (Seattle, about 1.5 million people, Spokane, about 200,000 people.) Edwards is only about 60 miles from the Los Angeles basin, where about 11 million people live. A minor error in shooting for Edwards could lead to a major accident, whereas a major error in shooting for Moses Lake could lead to a crew having to spend a few hours waiting to be picked up from downtown Yakima. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[barrykirk]

Capsules are small. This is an advantage for a re-usable<br />capsule in that it gives you flexability.<br /><br />A small capsule is easy/easier to ship around the country after landing to return it to it's launch point.<br /><br />This isn't like shipping an SRB or a shuttle external fuel tank.<br /><br />So, there is no major downside to an atlantic versus a pacific landing.

 

[Boris_Badenov]

I am beginning to think landing a capsule is a whole lot more difficlt than we have been led to believe. <br /><br />Gemini 3 – 84 kilometers short of landing point<br />Gemini 4 – 80 kilometers short of landing point<br />Gemini 5 - 130 kilometers short of the planned landing point<br />Gemini 7 - within 11.8 kilometres of the targeted landing point.<br />Gemini 6a - landing within 18 km of the planned site<br />Gemini 8 – because of attitude control problems, Gemini 8 landed 3 days early & in the Pacific instead of the Atlantic <br />Gemini 9 - 700 meters from the planned landing site<br />Gemini 10 - 5.6 km away from the intended landing site<br />Gemini 11 - 4.5 km away from the intended landing site<br />Gemini 12 - 4.8 kilometers from its target.<br />Apollo 4 - 16 km from the target landing site<br />Apollo 6 - 80 km from the planned touch down point.<br />Apollo 7 - 13 km (8 mi) north of the recovery ship<br />Apollo 8 – It was 43 minutes after splashdown before the first frogman from the USS Yorktown arrived, as the capsule had landed before sunrise<br />Apollo 9 – within site of recovery ship<br />Apollo 10 – <br />Apollo 11 - 24 km (15 mi) from the recovery ship<br />Apollo 12 – <br />Apollo 13 – 6.5 km (4 mi) from the recovery ship,<br />Apollo 14 – <br />Apollo 15 - 5.3 n mi (9.8 km) from the prime recovery ship,<br />Apollo 16- 5 km (3 mi) from the recovery ship <br />Apollo 17 - 6.5 km (4 mi) from the recovery ship<br /><br /> <br /><br /><br /> <div class="Discussion_UserSignature"> <font color="#993300"><span class="body"><font size="2" color="#3366ff"><div align="center">. </div><div align="center">Never roll in the mud with a pig. You'll both get dirty & the pig likes it.</div></font></span></font> </div>

 

[willpittenger]

<blockquote><font class="small">In reply to:</font><hr /><p>a major error in shooting for Moses Lake could lead to a crew having to spend a few hours waiting to be picked up from downtown Yakima.<p><hr /></p></p></blockquote><br />The Russians have had major misses quite recently. In fact, one had an American on board. There was also a case from the Soviet era in which the capsule went down in an area where the comsmonauts almost froze to death. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[PistolPete]

You'll notice that it was mostly the early capsules that were off course. Most of the Apollo capsules coming from the Moon actually landed within 10km of the target. I imagine modern inertial guidance controll systems would make it so that all of the Orion capsules would land on Murroc dry lake bed at Edwards.<br /><br />IIRC the Apollo capsule had a 0.8 hypersonic L/D ratio on re-entry. <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>

 

[PistolPete]

BTW, getting back to an idea I had earlier, I pulled this picture from a PDF about a NASA Refrence mission to Mars (July '97), it show the precursor to the CEV, something called an ECCV, with a parasail over the Cape. My idea would have the parasail facing the other direction, in essence the CEV would be flying "backwards" with the heat shield facing the water when it touches down. This would help cusion the foreward motion from the parasail. This would also increase the chances that it would end up "stable 1", or heat shield down, pointy end up in the water.<br /><br />Here's the link to the PDF that I got the picture from <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>

 

[darkenfast]

Halman, <br /><br />First, the CEV's re-entry profile is not a ballistic trajectory, the capsule generates lift (L/D's discussed in the ESAS report ranged from .3 to .4). In that report, the main chutes are planned for deployment at 10,000 ft, prior to which the capsule is descending through the various winds aloft at a fairly high speed. Data on those winds can be fed into the CEV's computer up to loss of signal (the CEV Command Module, unlike Apollo, has some maneuvering capability), and the skip return from lunar missions is expected to offer another oportunity to refine the trajectory. The ESAS report claims a crossrange capability of 100-110NM, and a predicted main chute opening well within 1.5NM's of the target point (they believe further analysis can get it down to .5NM. That leaves only the drift from 10,000 ft down to be predicted. The requirements for the landing sites were for a 5 to 6NM diameter. A ballistic re-entry (emergency procedure, spin-stabilized) will result in a water landing in the Pacific. I understand that Apollo got pretty good at hitting near to its target point (NOT the recovery ship, it was offset), and I have no doubt that the CEV will improve on that, mostly due to its ability to conduct small corrections after SM jettison. <br />Of course, a major malfunction during a lifting re-entry could result in a landing somewhere between the site and the ocean, but that has been a risk for the Orbiter as well, and the CEV has a vastly smaller "footprint" if it comes down somewhere unexpected.

 

[willpittenger]

I don't suppose there was a chance the capsule would land on deck. Be convenient if the crew could handle it -- and the ship's crew noticed. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[PistolPete]

A correction on the Apollo L/D ratio: according to astronautix.com the hypersonic L/D ratio for the Apollo CM was 0.30, the same as is planned for the CEV. <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>

 

[halman]

darkenfast,<br /><br />Just about any object except a sphere will generate lift when moving through an atmosphere. This is one of the reasons why the study of ballistics is so complex. When Columbia broke up, she was performing a series of 'S' turns to lose velocity. When a capsule can do that, I will accept that it is not traveling in a ballistic trajectory.<br /><br />But that is neither here nor there. We have advanced enough to be able to drop nuculear warheads within a few hundred meters of where we want them, at the same time that a bunch of other warheads from the same rocket are going to a bunch of other targets. There will be no problems with capsules landing in cities, or way out of the target area. In a way, that is a shame, because it might remind a few people that there is a space program. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[edkyle98]

"I don't think that the "stupid in general" comment is called for."<br /><br />Ditto. Scott Carpenter didn't become the second American to orbit the Earth by being "stupid". He didn't achieve the following by being "stupid". <br /><br />Education:<br />BS from University of Colorado, 1949<br /><br />Honors:<br />Fellow in the Institute of Environmental Sciences<br />Association of Space Explorers -USA member<br />Delta Tau Delta member<br />Legion of Merit award<br />Distinguished Flying Cross<br />NASA Distinguished Service Medal<br />Navy Astronaut Wings<br />University of Colorado Recognition Medal<br />National Aeronautic Association's Collier Trophy<br />New York City Gold Medal of Honor<br />Elisha Kent Kane Medal<br />Boy Scouts of America Silver Buffalo<br />Numismatica Italiana Award <br /><br />Posting a message that calls a genuine American hero "stupid" - now *that* is stupid!<br /><br /> - Ed Kyle