Does offset / hiding help with aerodynamic?

[Carrot]

I am trying hide / offset my parachutes inside my first stage / at the decoupler so I can gain some extra time to land my first stage and the surface of the rocket is round without any angles. However, it gave me unstable launches. I found those parachutes inside the decoupler (facing the top) are casing drag after I turned on the aeroforce indicator. Is there anyway to avoid this? Thanks

[Randazzo]

11 minutes ago, Carrot said:

I am trying hide / offset my parachutes inside my first stage / at the decoupler so I can gain some extra time to land my first stage and the surface of the rocket is round without any angles. However, it gave me unstable launches. I found those parachutes inside the decoupler (facing the top) are casing drag after I turned on the aeroforce indicator. Is there anyway to avoid this? Thanks

It is my understanding that all radially attached parts (unless they are physicsless - also assuming that is still a thing) will contribute to drag regardless of their offset orientation in stock aerodynamics.

FAR uses a voxel system which accounts for the overall shape of the craft, allowing you to hide things from airflow via offset.

[Rocket In My Pocket]

Try putting the parachutes inside a service bay.

Should keep them from producing drag. (I think...someone correct me if I'm wrong )

It doesn't look like it'd work but it does, except a few hiccups every now and then where it tells you they can't be deployed because they are stowed but all you have to do is close/open the doors real quick.

Edited January 8, 2016 by Rocket In My Pocket

[Snark]

3 hours ago, Randazzo said:

It is my understanding that all radially attached parts (unless they are physicsless - also assuming that is still a thing) will contribute to drag regardless of their offset orientation in stock aerodynamics.

FAR uses a voxel system which accounts for the overall shape of the craft, allowing you to hide things from airflow via offset.

I believe that this is correct.  The actual positioning doesn't matter-- the stock game simplifies everything to some number of vertical stacks.  Thing-on-top occludes thing-on-bottom within a stack, but radially-attached things make stacks of their own, regardless of their actual spatial relationship to the center thing they're attached to.

Interestingly, this is not the model that the game applies to re-entry heating.  Components do shield the parts behind them from heating, even though they don't shield them from drag.

As for so-called "physicsless" parts:  It's still a thing.  However, it behaves differently from the pre-1.0 days.  Before 1.0, the physicsless parts were totally free:  no mass, no drag, you could spam them all you want.  Now, they do generate mass (and, I believe, drag). However, what they do is to contribute their mass and drag to their parent part (or, if the parent part is itself physicsless, to the first part up the parent tree that isn't physicsless).  Therefore, for example, if you add a bunch of radially attached batteries to the side of a fuel tank, the batteries in effect just add mass and drag to the tank.  This means that you do "pay" for them overall, but you don't have to worry about whether (for example) they're symmetrically distributed.

[NathanKell]

Correct.

 

The reason for the difference is reentry heating can be occluded, whereas at least in subsonic flow air gets everywhere. So only the part of a suface-attached part that is literally inside another part should have drag ignored; if there's something in front of it but air can still reach it, it should cause drag.

That's why FAR switched to voxels, because you can do that with voxels.