Upside down lander on top of a delivery rocket

[Summer]

Hello!  First time poster but long-time Kerbonaut.

I have a fairly specific issue.  I've just gotten the tech tree to the point of usable landers+MPL+etc. and I'd like to build the lander (using a clamp-o-tron) in it's final position above the Mk1-2 command pod (then the separator below that, then the MPL, then engines, etc.).  My idea was to have the lander be in "final position" as it would be docking in space.  So I created the lander, flipped it over, then put the Mk1-2 pod under it and continued building.  

This, of course, produced the lander can as the primary pod in the system (since it was put in first) and gave various errors like "No parachutes" and "pod is upside down!"  After reading another tutorial about changing command pods (via editing the vehicle save file), even though that wasn't exactly what I wanted, I moved the Mk1-2 pod to the top of the file.  That didn't remove the error messages but it did make the navball work right.  

The only other method I thought of was to have the lander right side up at the top and use a stack decoupler to send it off on it's first mission, then dock with the clamp-o-tron normally on the way back.  But that would either require starting the kerbals in the lander can or doing an EVA to move to the lander before decoupling, both of which aren't ideal (the first due to realism, the second for simply being annoying).  If it matters, I'm playing on Science mode.  

So my question is:  is there a better way to do this?  

Thanks!

[steuben]

Try the lander as a subassembly.

I thing rerooting the whole vessel in the VAB/SPH may help as well.

The warnings/errors you see won't prevent launch. You just have to be sure you have addressed things it mentioned. Sometimes the t does see them even though you have.

[Summer]

I did try that before, but it seems I did it wrong.  It said (before) that "The selected part is not attachable!"  I didn't think to try removing the clamp-o-tron from the top of the lander, and then it worked fine.  It still complains about the command pod facing the wrong way, but everything else seems correct.

I think that's the answer then!  Thanks!

[Phil deCube]

I assume you are talking about the engineering report in the VAB giving you errors. Is that correct. I get around that by never looking at it. Complete waste of time IMHO.

I assembled the ship below in LKO. Once docked I shutdown the engine and set control from here to the main capsule. Then off to Jool/Eeloo/Moho. If you wanted to put the lander on upside down in the VAB, just set the capsule underneath (the right way up) as the controlling part on the launchpad.

[Plusck]

The only real problem with flipping your lander is trying to continue your build afterwards. The VAB can get confused about what is meant to be the right way up. A secondary problem is simply making sure you have another "controllable-from-here" part like a docking port facing the right way for the launch.

As @steuben said - try making it a subassembly, or simply save it separately and then load it into your new build using the "merge" feature. With either option you must make sure the game treats the bit you want to connect as the parent part to have an available node: if a subassembly, the only node it'll recognise is where you detached it when you made it a subassembly (so you attach something else to the top of the docking port, make that the root, then remove the rest and drop it into the subassembly box); if you want to merge, just make the top docking port the root before you save it.

A second reason for making it a subassembly (or merging it in) is that your launcher will then have its own root part that is facing the right way from the start, so the VAB doesn't get confused. Otherwise, changing the root part from one that has been turned from its default position can make the VAB flip or turn the entire rocket - not an insurmountable problem but a pain to have to deal with.

One final thing to note: since the ship isn't being built in a "standard" manner, you might find unexpected behaviour when separating craft, such as the game thinking that a discarded bit of rocket is the "main" vehicle rather than debris. Again, not a big deal if you realise what is happening, but it can add panic and confusion if you're still in the atmosphere .

Edited March 14, 2016 by Plusck
corrected for "parent" and "root" difference for subassemblies/merging

[Geschosskopf]

On 3/12/2016 at 6:31 PM, Summer said:

.....  My idea was to have the lander be in "final position" as it would be docking in space.  So I created the lander, flipped it over, then put the Mk1-2 pod under it and continued building.  

This, of course, produced the lander can as the primary pod in the system (since it was put in first) and gave various errors like "No parachutes" and "pod is upside down!"  After reading another tutorial about changing command pods (via editing the vehicle save file), even though that wasn't exactly what I wanted, I moved the Mk1-2 pod to the top of the file.  That didn't remove the error messages but it did make the navball work right.  

The only other method I thought of was to have the lander right side up at the top and use a stack decoupler to send it off on it's first mission, then dock with the clamp-o-tron normally on the way back.  But that would either require starting the kerbals in the lander can or doing an EVA to move to the lander before decoupling, both of which aren't ideal (the first due to realism, the second for simply being annoying).  If it matters, I'm playing on Science mode.  

So my question is:  is there a better way to do this?  

Thanks!

Welcome to the forums!

Anyway, the engineer report in the VAB is pretty much useless.  It assumes that you're building a totally conventional rocket, and doesn't even get that right, complaining about things that aren't really problems..  When it 1st appeared in the game, I spent about 5 minutes trying to make it happy, decided it was junk, and haven't looked at it since.  So, my advise is to ignore it.  Nothing it says has any effect.  Rockets fly just fine even though the report indicates many problems.

Moving on to your real question, there are 2 separate issues with your design:  construction and flying.  Flying is simple:  Before launch, right-click on some pod or probe core that's facing the correct direction, select "control from here", and away you go.  And if the lander returns and docks to the rocket at some later point, be sure to do that again.  Problem solved.

Now, as to construction....  As others have said, the easiest thing is to use the subassembly feature.  Build the lander by itself in the normal position, pointing up.  When you finish it, add an extra part (such as a structural box girder) on top of the docking port which is on top of the lander's cockpit.  Then use the select root tool to make that extra part the root.  You'll know you've succeeded here when you move the entire lander by dragging the extra part around.  Having done this, bring up the subassembly tab in the parts menu.  Now left-click and hold on the docking port and drag the entire lander (except for the extra root part) into the subassembly drop box in the lower left of the screen.  Release it there and save it as a subassembly.

Now start an entirely new rocket from scratch.  Start with the Mk 1-2 pod and build whatever rocket you want below it.  Put a docking port on top.  Now open the subassembly tab and select your previously saved lander.  It will appear in the VAB as a single unit you can attach to the new rocket.  It will have only 1 attachment node, on the docking port above the lander can.  So rotate the lander so it's upside down and attach its node to the node of the docking port on the Mk 1-2 pod.  Voila!

Having done this, the Mk 1-2 pod is now the root part of the new rocket.  It's the 1st part so SHOULD default to being the "control from here" part when you launch, although I'd still verify that manually just to be safe.  The Kerbals will start in the Mk 1-2 pod.  All is as you want it.

But the engineer report won't like it at all.  So what?