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Crew return capsule with docking port?


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Does anyone have a decent CRV (crew return vehicle) that is not a lifting body, which uses the stock 3-kerbal capsule and parachutes to return to Kerbin from LKO (low Kerbin orbit)?  I need something that can be docked to a space station, relatively inexpensive, and which can return 3+ kerbals from orbit.  Pictures would be appreciated.

It seems like the best design would be to put the docking port on the top of the capsule, along with (4) radial parachutes.  But it's tough to figure out placement of things given the weird geometry of the 3-kerbal capsule.  Maybe I should just block the hatch and not allow EVA.

My other option I guess is to use the 1-kerbal capsule stacked on top of something else like the 2-kerbal control module.

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Put the docking port on top as you described and go with just two radial parachutes not blocking anything. The return-capsules are pretty strong and can easily survive a rougher landing. So two chutes on the sides should be good enough. I play with mods including FAR, but it should work in stock as well.

If you play modded, there is an inline parachute module in the "real chutes" mod that can fit on top of the mk2 capsule and you can still put a docking port on top of that.

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1.25m utility bay on top of the capsule, with a docking port on top of that. Inside, a probe core with 3 parchutes attached. Set them to deploy at 0.4 pressure, make sure the bay is open and deploy before you run out of charge. Your pod is now automated and can carry tourists!

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4 hours ago, WuphonsReach said:

Does anyone have a decent CRV (crew return vehicle) that is not a lifting body, which uses the stock 3-kerbal capsule and parachutes to return to Kerbin from LKO (low Kerbin orbit)?  I need something that can be docked to a space station, relatively inexpensive, and which can return 3+ kerbals from orbit.  Pictures would be appreciated.

It seems like the best design would be to put the docking port on the top of the capsule, along with (4) radial parachutes.  But it's tough to figure out placement of things given the weird geometry of the 3-kerbal capsule.  Maybe I should just block the hatch and not allow EVA.

My other option I guess is to use the 1-kerbal capsule stacked on top of something else like the 2-kerbal control module.

Unless you plan to fly IVA, you don't need to see out the windows.  And if you can use the crew transfer function while docked, you don't need the hatch.  So probably, you don't need to worry about blocking windows and hatches on the CRV, which means you can place the chutes however you want.

If the aesthetics of blocked hatches and windows bother you, or if you actually need to use either one, then the simplest thing is to put something light-weight between the capsule and the docking port, then attach radial chutes to that.

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Storm, why the service bay, it's just an extra part. I have a station which has 8 of those pods attached...  Mk2 with probe core and port on top, three radial chutes, heatshield, decoupler, small tanks and engine for 300-350 dV for a suicide burn. 10 parts.

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I run a 7-kerbal shuttle bus - Mk2 capsule and a hitchhiker can with a 2.5m heat shield (which I should really put a decoupler on)- with three drouges and three radial chutes. It does take type-2 landing legs, as it tends to land at about 10.5 m/s (which is why I should add that decoupler). Covered docking port top, just because it looks neat, and an RCS system with 4 small round tanks (because I suck at docking). 

 

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I would agree with the need for only two radial chutes, three at most. I think when chutes were balanced, it was about 2.5 radials to get similar performance as the stack chute, which is more than enough.  The Mk1-2 capsule has a crazy high crash tolerance when compared to the other pods (it's also heavier per crew seat). If all you want is a pod with chutes and a docking port, 2 should do it.

None of that considers fuel/engines to deorbit though. You might need to have consideration for that. Often times a couple sepratrons will do the trick.

 

Cheers,

-Claw

Edited by Claw
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Didn't see anyone mention this, but:

Don't use the 3-kerbal command pod.  It's extraordinarily overweight, it weighs 4 tons!  Just use a Mk1 command pod sitting on top of the 2-kerbal passenger cabin.  It's less than half the mass, plus you don't have to go up to a 2.5-m stack.

Stick a small-size docking port on top of the command pod, put a couple of radial parachutes on the sloping sides of the pod.  If you want to save some drag on ascent, put an upside-down decoupler on top of the docking port with a small nosecone on top of that-- you can pop the cone off once you're out of atmosphere.

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As others have said, just use 2 chutes and a shielded port on the top. If not that, use a nosecone/decoupler over a normal docking port for ascent.

As per the weight of the size-2 pod, I don't care, it's still the most stylish way of flying 3 kerbals without strange aerodynamic effects like the Mk2 crew cabin.

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1 hour ago, moogoob said:

As per the weight of the size-2 pod, I don't care, it's still the most stylish way of flying 3 kerbals without strange aerodynamic effects like the Mk2 crew cabin.

Except that now we have the Mk1 crew cabin, which fits the bill very nicely.  :)

The 3-kerbal pod is certainly attractive to look at... but now that we have a decent 1.25m crew cabin, the mass just really sticks out.  Doubling the mass of the payload means doubling the mass of the entire rocket, which means doubling the cost; and the OP mentioned inexpensive as a goal.

Here's a rocket that costs 13.6K funds, can put three kerbals into 125-km circular orbit with over 700 m/s of dV to spare, reenters with no problem.

fsOz0Bs.png

It's somewhat over-engineered-- if you only need to get to <90km and don't need a lot of dV to spare, you could probably make do with Hammers rather than Thumpers.  I've deliberately kept it fairly low-tech as pictured; this should be buildable quite early in career.

Not shown in the picture is an OX-STAT panel on the rear side of the command pod to keep the battery topped off.

The two chutes drop it at just a hair over 7 m/s at sea level, which is slightly over the impact rating of the Terrier.  It can drop into the ocean just fine, but if you're coming down on land and don't want to lose the Terrier's recovery value, you may want to keep just a smidge of fuel in reserve to cushion the landing.

Edited by Snark
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18 minutes ago, fourfa said:

The size small docking port doesn't allow crew transfer, FYI.  I have bad luck with kerbals flying EVA breaking solar panels around space stations...

That would be pretty weird considering that Kerbals have no problems transfering through fuels tanks or girders. :huh:

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my early 3-kerb missions look like snark's vessel. later on I use the mk2 with a hitchhiker underneath. I just built a mun returner for 7 ppl kbl with RCS and docking port for 91k. reentry and touchdown were... interesting, but with a few tweaks it can surely survive a minmus return as well.

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1 hour ago, Harry Rhodan said:

That would be pretty weird considering that Kerbals have no problems transfering through fuels tanks or girders. :huh:

http://wiki.kerbalspaceprogram.com/wiki/Clamp-O-Tron_Docking_Port_Jr.

Product description

Originally marketed as a child-size version of the normal Clamp-O-Tron, the Clamp-O-Tron Jr. soon found use among hobbyists and professional space agencies alike for its compact profile, lightweight structure, and all-round cuteness. As a result of its small size, it's usable for transferring resources, but not crew.

The remark in the quoted description about not being able to transfer crew indicates that this is the only docking port which cannot transfer crew between docked sections. In past versions, no port could transfer crew, but this has changed as of 0.25.

 

Well, that's what it says in tool tips and on the wiki.  Of course, it occurred to me to actually check in-game and it seems that crew can transfer through the Jr docking port just fine.  So ignore my comment completely!

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I've got a three-Kerbal rocket that uses the Mk 1 inline cockpit, the two-kerbal cabin, a Rockomax fuel tank and a pair (or it is three...) of Thuds that doesn't currently have a docking port, but I feel replacing its nosecone with a shielded port wouldn't affect it too badly.  It's sufficient to make a 150K rendezvous with my space station and return (great for LKO rescues and tourist hops, too).  With four radial chutes it's recoverable without decoupling anything but the SRBs I use to kick it up to decent altitude, so you're only out the cost of fuel and boosters.

I'm now curious to see whether or not I could replace the cockpit/cabin setup with the three-man pod (which I also like the aesthetics of) and still have similar performance.  I can post pics of my current ship when I get home, if you want, and I can do some experiments with the capsule tonight.

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One thing that I experimented with tonight was stacking the 3-kerbal white pod under the 1-kerbal grey pod, with the docking port on top.  Toss a 2.5m heatshield with 160 units of Ablator on the bottom, add some RCS thrusters, plus four radial chutes, a few OX-STAT panels, and four round RCS tanks.  I gave up making it try to look pretty.

The result is something that looks a bit funny but has enough dV to get down from LKO.  Landing speed is about 6.5 m/s at ground level on Kerbin with the (4) radial chutes.

Back in 0.90, I had a lander which used the old 2.5m kerbals-in-a-can part, slung under the 3-kerbal capsule along with lander legs on the sides of the bottom can.  But those legs keep burning off during reentry now in 1.0.5.

I'll have to try some of the 1.25m part ideas, such as the crew cabin.

I've also done a few tiny landing probes on Kerbin that use an oversized heat shield as the craft bottom.  I just dial back the ablator amount to lighten it up.  On the way up to orbit, I can hide it all in a procedural fairing.  So I may end up just putting the 1 kerbal capsule on top of the 2.5m heat shield rather then try and use legs.

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2111no0.jpg

The standard Apollo style layout is fine for the 3 men capsule, with two radial parachutes. During launch there would be a LES tower attached to the top.

However this is my general purpose spacecraft that I use to go anywhere within Kerbin SOI, it has 1000+m/s of delta-V in its service module. If you want to make a craft that is only used to go between ground and LKO then this is overkill. If you look closely at the capsule you notice it has storage for both electricity and monoprop, turns out that's enough to deorbit the capsule without any service module at all!

What you do in the VAB is to put the docking port on top, heat shield below and two radial parachutes around it. Then make sure the capsule has full electricity and monoprop and toggle usage for those two resources off for the capsule. Then attach two of those single direction RCS thrusts so they point forward.

Then when you're in orbit (say, attached to a station with crew boarded waiting to come back) you just undock, switch on electricity and RCS in the capsule, tap the RCS thrust to back away, then point your capsule prograde and fire the RCS. The monoprop stored inside the capsule should be more than enough to deorbit it.

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Here's the rocket I was talking about.  Sufficient to launch, orbit, do up to a 150K rendezvous and return, though at that altitude fuel gets alarmingly tight.  Nosecone is the usual, but I don't thing a shielded port would affect drag enough to prevent similar performance.

267deb74f2b2b97e3e9e034e55606302.jpg902915cf6601c8240cf6068decae7c7a.jpg

Edited by Captain Vlad
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