What's wrong with this ship?

[JackBush]

I copied this from a Youtube tutorial and am pretty sure I have it identical. His flew. But mine just turns sidewise out of the shute and collapses. I think the tut was for an earlier version and I'm playing 1.0.5 but, nevertheless, what's a guy to do when he doesn't know how to design a ship. I want it to land on either Minmus or Mun, get a ton of science, and skedaddle back home.

Rip it apart, gang, but give me something that will do the job.

 http://imgur.com/uYpkMXa

[Streetwind]

It has more or less the same problem that pretty much all the designs have that you come to the forums with to ask about... you have a lot of radial/surface attached parts sticking out at the top. You need to somehow wean yourself off of sticking giant things like the science jr's to the side of the stack. People did this in older versions because back then it didn't matter; nowadays it does.

The rule of the thumb for rockets is "heavy bits at the front, draggy bits at the back". The rocket you have on the pad here has draggy bits at the front, which is the reverse of the rule. So in order to comply with the rule, the rocket will seek to reverse itself and fly backwards, and you will not go to space today. Makes sense?

Edited December 3, 2015 by Streetwind

[Mister Dilsby]

Aero forces at launch are much more important than they were in, say. 0.24 which is what that.... thing looks like it was made in  My advice is to start with that Mk1 capsule and work your way down, swapping out those wide, flat aerodynamic nightmares and taking advantage of the newer parts to make a nice streamlined ship--you know, something that actually looks like a rocket and not a coathanger with a nozzle. Functionally, all your drag should be at the tail in the form of some nice clean fins--not at the top, where it's going to yank your nose around like pulling the bridle on a horse. 

Hope that was helpful. Good luck! Start small! Launch! Crash! Learn! 

[Tex_NL]

Aerodynamics have been severely changed over the last few versions. Drag has become something you can no longer ignore. This design is very drag heavy in the nose. The only suggestion I can give you if you're set on flying this is to go slow. Drag increases exponentially the faster you go.

You can improve the ship slightly by loosing two of the materials bays and placing the remaining one in line with the pod and engine.

[Snark]

As previous posters have said, things have changed. Radically. Beware of following any advice that dates before May 2015, it's almost certainly badly wrong.

Not only do you need to be more aerodynamic now, but also other rules have changed. For example, why the dickens does that ... thing ... have not one, not two, but THREE Science Jr.s stuck to it? Probably because it's from the old pre-1.0 days when you needed a science lab to reset them. These days, a scientist can do it. So just crew your ship with a scientist, and you only need one of them, not three. Which in turn means you can put it in-line in your main stack, and not have it bolted onto the side like some sort of draggy tumor.

So it comes down to the usual. Heavy bits in front. Draggy bits in back. Streamline.

I might also suggest that you target Minmus first, rather than the Mun. The navigation is trickier, but the dV requirement is much less. You'll be able to pick up enough science to give you better options for building your Mun lander.

 

 

Edited December 3, 2015 by Snark

[GoSlash27]

Jack Bush,

 Just looked at the pic in the original post, and "oh dear"

 Yeah, the others have got it covered.

So... you want a manned ship that will land on Mun or Minmus, collect a full array of science, and return to Kerbin. We can do that.

Are you dealing with any restrictions? Tech level, pad mass, etc?

Also, how comfortable are you with math? I can explain my process, but it's math heavy.

Best,

-Slashy

Edited December 3, 2015 by GoSlash27

[JackBush]

Okay guys, I get the message. That pretty well wipes out all the Scott Manley and Orb8ter tutorials. So where can i go for step-by-step guidance to building a good ship for Minmus? That's really all I'm looking for.

I appreciate your help.

[Waxing_Kibbous]

What's your tech level at? Minmus is really easy once you get there, but getting there is a little bit more complex than Mun. You want your second stage to be pretty beefy, enough to match Minmus' inclination once in Kerbin orbit, then enough to get to Minmus.  Doing all the maneuvers around Minmus/getting back home takes very little fuel compared to Mun so the lander can be pretty lightweight. This is about as basic as you can get, Val in the command pod and Bob in the can:

edit: Bob can EVA every step of the way and collect data/reset the goo and Jr for juicy gobs of science. Obviously this design needs electrical stuff, usually I put a battery on the back of the pod and panels wherever.

Edited December 4, 2015 by Waxing_Kibbous

[GoSlash27]

1 hour ago, JackBush said:

Okay guys, I get the message. That pretty well wipes out all the Scott Manley and Orb8ter tutorials. So where can i go for step-by-step guidance to building a good ship for Minmus? That's really all I'm looking for.

I appreciate your help.

Jack Bush,

 I was about to say that there isn't a step by step guide out there, but you do have a very good resource to learn from:

These folks have created lots of designs and even videos about how to get to Minmus and beyond in KSP 1.0 without facility upgrades.

 Should be very helpful. I recommend 5thHorseman's "HMV Plays" video series.

Best,

-Slashy

Edited December 4, 2015 by GoSlash27

[Snark]

1 hour ago, Waxing_Kibbous said:

What's your tech level at? Minmus is really easy once you get there, but getting there is a little bit more complex than Mun. You want your second stage to be pretty beefy, enough to match Minmus' inclination once in Kerbin orbit, then enough to get to Minmus.  Doing all the maneuvers around Minmus/getting back home takes very little fuel compared to Mun so the lander can be pretty lightweight. This is about as basic as you can get, Val in the command pod and Bob in the can:

Or if you can get an OKTO core, you can skip Val and just fly with Bob.  Will cut down weight a lot, those command pods are heavy.

Also:  If you do go to Minmus, be sure to do it the right way, you need to save all the dV that you can.  There are a few different ways that work well, but just about the worst possible one is the one that lots of people do (and which Waxing_Kibbous suggests above).  And no criticism implied or intended (to Waxing_Kibbous or anyone else), I started out this suboptimal way myself. 

The worst possible way to go to Minmus is to get into an low Kerbin equatorial orbit, then change your orbital inclination to match Minmus, then do a burn to go to Minmus.  This is really, really bad because it wastes a few hundred m/s of dV to do the plane change.  The worst possible place to do an orbital inclination change is at low altitudes.

Here are three separate ways to do it that are all reasonably good.  Not identical in terms of dV, but they're significantly cheaper than the abovementioned method, and they're not all that far apart.

Option 1. Launch straight into the right inclination (or pretty close to it).  That is, wait until KSC is in the correct position (directly under Minmus' orbital path, where it crosses the equator).  Then when you launch, don't launch due east-- launch just a few degrees north or south of east, so that you're already lined up with Minmus' orbital trajectory.  The part that gives newbies a challenge is figuring out when to launch.  The easy way to eyeball this:  Switch to map mode, then double-click on Kerbin so that Kerbin itself (not your ship) is the focus of map view.  Then zoom out until you're a bit beyond Minmus, and rotate the camera view until you're looking at Minmus' orbit perfectly edge-on (i.e. it collapses to a straight line passing through the center of Kerbin).  Then just timewarp until KSC (and your ship) rotates to be right plumb spang on that line.  (Another option that may be handy, if you're going to be making many trips to Minmus, is to put a dinky little satellite in LKO and adjust it to have zero inclination relative to Minmus, then just leave it parked there.  You can then use your satellite's orbit as a guide marker for launching.)

Option 2.  Launch into an equatorial orbit.  Wait until Minmus is just under 90 degrees before its AN/DN with your orbit.  Do your burn at the node, so that when you intersect Minmus, it will be right at the DN/AN.  (This means you'll have a steeply inclined orbit at Minmus when you arrive, which may or may not be good for you, depending on what your goal is).

Option 3:  Launch equatorial.  Do your go-to-Minmus burn equatorial, so that it puts your Ap out at about the level of Minmus' orbit, but there's a good chance that you don't actually have an intercept because your inclination doesn't match.  Drop a 2nd maneuver node about halfway between Kerbin and Minmus, and do your correction burn there-- it'll be much cheaper than if you had adjusted inclination while in LKO.

[JackBush]

12 hours ago, GoSlash27 said:

Jack Bush,

 I was about to say that there isn't a step by step guide out there, but you do have a very good resource to learn from:

These folks have created lots of designs and even videos about how to get to Minmus and beyond in KSP 1.0 without facility upgrades.

 Should be very helpful. I recommend 5thHorseman's "HMV Plays" video series.

Best,

-Slashy

Slashy: That looks great; just what I need. I look forward to watching the series. I have no math and this "game" strikes me as so complex I really  need help. Otherwise it's just frustrating.

[JackBush]

13 hours ago, Waxing_Kibbous said:

What's your tech level at? Minmus is really easy once you get there, but getting there is a little bit more complex than Mun. You want your second stage to be pretty beefy, enough to match Minmus' inclination once in Kerbin orbit, then enough to get to Minmus.  Doing all the maneuvers around Minmus/getting back home takes very little fuel compared to Mun so the lander can be pretty lightweight. This is about as basic as you can get, Val in the command pod and Bob in the can:

edit: Bob can EVA every step of the way and collect data/reset the goo and Jr for juicy gobs of science. Obviously this design needs electrical stuff, usually I put a battery on the back of the pod and panels wherever.

I don't mean to be rude, Waxing, but isn't this the kind of top-heavy lander I've just been critiqued for?

[Death Engineering]

I'm not wearing my glasses, but that looks like the fuel lines are leading to adjacent boosters in like a non-symmetrical asparagus. 

[Guest]

Op says ship "just turns sidewise out of the shute and collapses". Really need to see the navball in the screenshot. It sounds like a "control from here" issue to me, op does have mechjeb on the ship. Also, it would help to have a link to the craft file so that I can download and test.

[Snark]

2 hours ago, JackBush said:

I don't mean to be rude, Waxing, but isn't this the kind of top-heavy lander I've just been critiqued for?

Top-HEAVY is a good thing for aero stability. Top-DRAGGY is bad. The pictured lander is actually not too bad for drag, that Mk1 pod is reasonably streamlined and the two outrigger tanks have nosecones on them. And that lander, when packing a full fuel load, is very dense in terms of kilograms per vertical meter, so I suspect that it would fare reasonably well if you perch it on top of a tall, skinny ascent stage that has some fins on the back; it will really pull the CoM forward.

Edited December 4, 2015 by Snark

[JackBush]

31 minutes ago, Snark said:

 

Thanks, Snark. That explains a lot. Will give it a shot.

[fourfa]

19 hours ago, Snark said:

why the dickens does that ... thing ... have not one, not two, but THREE Science Jr.s stuck to it? Probably because it's from the old pre-1.0 days when you needed a science lab to reset them. These days, a scientist can do it. So just crew your ship with a scientist, and you only need one of them, not three.

 

There is additional science value in returning with three Science Jr reports.  If you have a pilot and scientist in separate cabins, then you can return with three copies, one in each cabin and one on the lab.  If you put in a probe core and just one cabin, well it's not a huge hit.  The second copy is essential though.

The temp and pressure scans are only good once (IIRC from all my mun missions) but all the other ones bring additional value up to like seven reports.  Goo, Sci Jr, and gravity scans really pay bonus on multiple reports.  Storage is the issue though.

[Snark]

2 hours ago, fourfa said:

There is additional science value in returning with three Science Jr reports.  If you have a pilot and scientist in separate cabins, then you can return with three copies, one in each cabin and one on the lab.  If you put in a probe core and just one cabin, well it's not a huge hit.  The second copy is essential though.

The temp and pressure scans are only good once (IIRC from all my mun missions) but all the other ones bring additional value up to like seven reports.  Goo, Sci Jr, and gravity scans really pay bonus on multiple reports.  Storage is the issue though.

That may give you a smidgeon, but the extra science is fairly minimal.  The first copy brings the lion's share of the science points; having a separate copy to get the remainder is really not worth it IMHO.  (And the third-and-later copies give vanishingly tiny benefits, like 1 science point, so definitely not worth bothering with.)

Especially since this is an early-career ship.  If he lands on some Mun (or Minmus) biome with this, he's going to be going back again later on, in order to reap the benefits of newly-researched science experiments.  Easy enough to pick up the second Science Jr. copy on the second trip.

It's up to the OP to decide whether lugging along a second Science Jr. (or crew cabin) is worth the bulk and mass, in exchange for a relatively small amount of additional science that would get reaped later on anyway, but I've certainly never found it worth bothering with in my own career games.

[Waxing_Kibbous]

Yeah, the method I suggested to get to Minmus isn't optimal, but IMO it's conceptually the simplest. After getting to Minmus becomes old hat then getting there more cleanly becomes clear.

Regarding the Scott M vids, starting here: https://www.youtube.com/watch?v=MHt162az5Y8

Minmus: https://www.youtube.com/watch?v=ZZ5AvIHOSQg

should be close enough to the current KSP version to get one started

[JackBush]

On 12/4/2015, 5:27:07, Waxing_Kibbous said:

Yeah, the method I suggested to get to Minmus isn't optimal, but IMO it's conceptually the simplest. After getting to Minmus becomes old hat then getting there more cleanly becomes clear.

Regarding the Scott M vids, starting here: https://www.youtube.com/watch?v=MHt162az5Y8

Minmus: https://www.youtube.com/watch?v=ZZ5AvIHOSQg

should be close enough to the current KSP version to get one started

Thanks for the links Waxing. The second is a tremendous help. I copied the ship identically and it flies beautifully. Recommend this particular series highly.

[monophonic]

On Fri Dec 04 2015 17:28:35 GMT+0200, Snark said:

Top-HEAVY is a good thing for aero stability. Top-DRAGGY is bad. The pictured lander is actually not too bad for drag, that Mk1 pod is reasonably streamlined and the two outrigger tanks have nosecones on them. And that lander, when packing a full fuel load, is very dense in terms of kilograms per vertical meter, so I suspect that it would fare reasonably well if you perch it on top of a tall, skinny ascent stage that has some fins on the back; it will really pull the CoM forward.

You could also put nose cones, inverted ("tail cones"), below the outrigger tanks for even less drag.

[Concodroid]

This happened to me when I built the World's Fastest Probe...

Just add fins(this will help, trust me.)

The World's Fastest Probe is the cube probe thing with the biggest rocket engine strapped to it. it was awesome.

[FancyMouse]

On 12/4/2015, 11:47:12, Snark said:

having a separate copy to get the remainder is really not worth it IMHO.

I don't quite agree - the benefit comes from second copy of material study and surface sample, either one is still like an extra first-time temperature scan. After a few hops the second pod will easily give a few hundred extra sci points, meanwhile it's just marginally harder to design the ship. Definitely worth it in early career.

And the lonely kerbal can have a companion. How good is that.