Oscar B vs Mk 0 tank balance problem

[AeroGav]

Something's not right here.

The Oscar B is the same diameter as, and one third the length of, the mk0 liquid fuel fuselage.

Yet, it has nearly the same capacity - 18 LF and 22 OX  , versus 50 LF for the mk0.  

Granted , the empty mass of the two tanks is the same, which comes out slightly in favour of the Mk0.  Perhaps the Oscar is highly pressurised, enabling it to store 80%  of  the mk0's liquid volume in only 33% of the space 

The kicker however, is that the Oscar has only 20% of the drag.   Given that the Mk0 is more likely to see service on air aircraft or spaceplane and the Oscar in a space probe , i'd say that's what matters.

[Streetwind]

That's just one out of a great many examples of the fact that KSP has no volume units.

To change this, you'd need a project the scale of the rocket part revamp. Which was unfortunately put on hold for the time being. So there's pretty much no chance that this will change anytime soon...

[Leafbaron]

For now, just do the Kerbal thing and exploit the hell out of it. 

[AeroGav]

2 hours ago, Streetwind said:

That's just one out of a great many examples of the fact that KSP has no volume units.

To change this, you'd need a project the scale of the rocket part revamp. Which was unfortunately put on hold for the time being. So there's pretty much no chance that this will change anytime soon...

Well, the mk1 parts are all the same diameter and the ft800 looks to be 8x as long as the ft100,  and elsewhere all parts of one diameter are roughly consistent with others of the same diameter, though there is a problem with 2.5m having so much better capacity/drag than anything else and mk2 airplane fuselage parts being horrendously worse than mk1 and 3.   But in this case Squad aren't even being consistent within the size 0 group

[Red Iron Crown]

3 hours ago, AeroGav said:

The kicker however, is that the Oscar has only 20% of the drag.   Given that the Mk0 is more likely to see service on air aircraft or spaceplane and the Oscar in a space probe , i'd say that's what matters.

How did you calculate the difference in drag?

[AeroGav]

5 minutes ago, Red Iron Crown said:

How did you calculate the difference in drag?

Alt f12, enable aero forces display in action menus.   Had the action menus of both tanks pinned on my screen and the drag numbers were 5x larger on the mk0

[Red Iron Crown]

2 minutes ago, AeroGav said:

Alt f12, enable aero forces display in action menus.   Had the action menus of both tanks pinned on my screen and the drag numbers were 5x larger on the mk0

Same position in the stack (i.e. both ends covered by another part)? I would expect it to be about 3x given that the Mk0 has about 3x the wetted area, 5x makes me think some other factor is involved.

[AeroGav]

6 minutes ago, Red Iron Crown said:

Same position in the stack (i.e. both ends covered by another part)? I would expect it to be about 3x given that the Mk0 has about 3x the wetted area, 5x makes me think some other factor is involved.

OK, i  ran a test with a rocket and the two tanks adjacent on the stack, this time the difference was only 3x.    I think the external fuel tank of my plane might have been flexing and going off prograde, resulting in the 5x .  3x is still a very bad penalty though given the two hold almost the same amount of fuel,  in a spaceplane.      It's a nerv powered ship so it doesn't really need lf/o.  It's also supposed to be stock, so i can't just use a mod to change the oscar b into a jet fuel only tank.