Make the PPD-12 Cupola lighter

[Bartybum]

I've noticed that the mass of the BBD-12 Cupola Module has a mass of 4.5, whereas the bulkier Mk2 Lander-can only has a mass of 2.5. This is fairly unreasonable in my eyes as the Mk2 Lander-can is clearly larger than the Cupola, which itself is too fragile for its mass (Cupola).

Thus, my suggestion is that either Squad reduce the mass of the Cupola to 3 or increase its durability.

EDIT: Mass 3, not 2

Edited November 11, 2013 by Bartybum
Mass 3, not 2

[stupid_chris]

It's heavier because it has large glass windows, which is very heavy stuff compared to the pod's aluminium

[Bartybum]

I know that (probably should edit to mass 3 instead), but then you compare that with the mass of the X200-8 fuel tank...

[stupid_chris]

Glass has a much higher density than LFO

[Bartybum]

Yes, but there's much more LFO than Glass

[vexx32]

I'd recommend actually doing some math to work out just how much glass is actually on the pod (assume a reasonable thickness for an airtight spacecraft pod), and compare that to how much LFO should be in the tank. I have a hunch you'll find it's fairly close to how it should be.

[Bartybum]

Alright, then if not decrease the mass, then why not increase the durability?

[vexx32]

Same reason. Glass is fragile. Unless you want to say they have windows made out of diamond, I don't think it should be made stronger.

[Algiark]

In gameplay terms, what is the purpose of the Cupola anyway? Aside from having a pretty view from the IVA?

[CosmicX1]

None really, but having the cupola is authentic, since it's something a real space program would have. Perhaps the cupola could generate a little more science from crew reports since the crew have a better view of their surroundings in the cupola?

[Smidge204]

Same reason. Glass is fragile. Unless you want to say they have windows made out of diamond, I don't think it should be made stronger.

Glass isn't fragile, it's brittle. Big difference there. Glasses are some of the toughest materials you'll encounter in your daily life.

The X200-8 has a total fuel mass of 4.0 t for 800 liters of fuel (360+440). That's 5,000kg per cubic meter (average), which is handily twice that of fused silica glass. In other words, a solid chunk of aerospace grade glass the size of the X200-8 fuel tank would be under 2 tons.

The Cupola isn't solid glass, of course. But it does have other things... like 9 kNm of torque and 200 E of electrical charge capacity. If we compare those specs to their dedicated counterparts (reaction wheels and batteries) we'd add 0.225t and 0.01t respectively... so 0.235t of that mass can be accounted for.

It seats one Kerbal, so we can give it everything a Mk1 Command Module has and add 0.8t. Total mass so far, unjustifiably rounding up, is 1.1t. We can be generous and double that because hey, they have Snacks on board! 2.2t. We're still half of what it currently is. You can't blame this on the glass, because even if it were entirely made of solid glass and added it to that 2.2t we still would not be 4.5t in total.

TL;DR: Yeah, I agree the Cupola module is too heavy for what it is. 3 tons sounds reasonable to me, maybe even 2.5, without any further justification for where that extra mass is hidden.

=Smidge=

[Dunbaratu]

I'd like to see a big window on the hitchhiker can. Give the passengers on space stations some nice views. Something where it's a bit heavier because of the glass, but doesn't have all the other stuff adding mass like the torque and the controls and everything else.

[pizzaoverhead]

having the cupola is authentic, since it's something a real space program would have.

Well, aside from the large instrument panel right across the middle of it detracting from its main purpose (wide viewing area). It's overweight, underprotected and lacks the use of a large part of its windows. It needs some tweaking. The one big disadvantage of the real cupola that isn't modelled in the game is that it's a massive hole in the station's thermal insulation.

[rosenkranz]

Would they actually use glass? or an high density polymer plastic resin?

I also agree it's too heavy. The orginal part it is based on was a 3-kerbal pod from KSPX and was a bit bigger. It was essentially a alternate to the mark 1-2 pod which weighs in at 4t.

I think they just forgot to adjust the mass after they tweaked the model and crew capacity.

[coolitic]

None really, but having the cupola is authentic, since it's something a real space program would have. Perhaps the cupola could generate a little more science from crew reports since the crew have a better view of their surroundings in the cupola?

Yeah good idea. I imagine the devs must have been finding a good alternate use for it.

[Sirrobert]

In gameplay terms, what is the purpose of the Cupola anyway? Aside from having a pretty view from the IVA?

It's very pritty on my space stations.