Nose cones won't alter COP

[Garrygirthoak]

Hi all,

I've run into what seems like a bug, if i try use a nose cone (all size i currently have unlocked) the COP in VAB and SPH will remained glued to the floor.

There are only a few select command modules like MK1 pod , MK1-3 pod and MK2 CP will actually shift the COP or COL off the floor. Don't think MK1 CP changes it, might have to go back....anyway.

I can backup my saves, craft ect and try reinstalling but i wanted to know if this is a bug or a feature?

Edit: This happens with any new craft I'm currently building or stock/prebuilt caft.

https://imgur.com/6h0EetT

https://imgur.com/ScHsfp9

https://imgur.com/xGI5sKL

 

Edited March 3, 2020 by Garrygirthoak
Additional information

[VoidSquid]

That's perfectly normal, KSP does not display the CoP but the CoL. And since your rocket has no lifting surfaces like wings, the CoL is irrelevant here.

If you search the forum, you'll find several threads about this topic over the years.

[Superfluous J]

The purple circle with the arrow is the center of thrust, and when you only have one engine providing all the trust, the CoT will always be centered on that engine.

[VoidSquid]

He was talking about the blue-turquoise sphere, CoL, not the purple CoT one.

Edited March 3, 2020 by VoidSquid

[Garrygirthoak]

8 minutes ago, VoidSquid said:

That's perfectly normal, KSP does not display the CoP but the CoL. And since your rocket has no lifting surfaces like wings, the CoL is irrelevant here.

If you search the forum, you'll find several threads about this topic over the years.

Im being a little lazy by asking, but why does KSP consider the command pods or Cockpits surfaces that changes it from displaying COL to COP? Why don't the nosecones have the same effect?  I've tried searching up terms but i haven't found anything specific to this particular question.

[VoidSquid]

You should ask Squad about those why questions, their design decisions, not mine  

But again, there is no CoP display / indicator at all in KSP, CoP is not modelled.

Edited March 3, 2020 by VoidSquid

[Garrygirthoak]

14 minutes ago, VoidSquid said:

You should ask Squad about those why questions, their design decisions, not mine  

But again, there is no CoP display / indicator at all in KSP, CoP is not modelled.

Ahhh i see, well thanks for your replies. I'll be definitely asking squad questions.... i'll let you know if they get back to me

 

[AHHans]

39 minutes ago, Garrygirthoak said:

Im being a little lazy by asking, but why does KSP consider the command pods or Cockpits surfaces that changes it from displaying COL to COP?

It doesn't change from displaying CoL to CoP, it keeps  displaying CoL. And the CoL moves when you add a command pod, because the bottom side of the command pod is a lifting surface. That way it generates more drag - well, deceleration - when entering the atmosphere which makes it easier to bring your Kerbals back home alive.

P.S. O.K. That's only for the MK1 and MK1-3 command pods and all the ablative heat shields. The MK2 cockpits have a lifting surface because the shape of the MK2 parts gives all the MK2 parts a lifting surface.

Edited March 3, 2020 by AHHans
Added P.S.

[Garrygirthoak]

Just now, AHHans said:

It doesn't change from displaying CoL to CoP, it keeps  displaying CoL. And the CoL moves when you add a command pod, because the bottom side of the command pod is a lifting surface. That way it generates more drag - well, deceleration - when entering the atmosphere which makes it easier to bring your Kerbals back home alive.

Many thanks AAHans! Right, makes me wonder if i should just design things in rocksim. Simpler times when i was building model rockets. I'd see where the salability marker (which coincidentally is also blue) and the COM, it would give me a readout of the stability margin. Generally the readout would be either over or under 1. 

[VoidSquid]

Don't make things too complicated, keep the CoM good ahead of CoT, don't overdo AoA in atmosphere, and everything should be fine. Just enjoy the game  

P.S.: And after a not-so-long time, you'll find your very own style building rockets, and you'll know by instinct what will work and what not. It's been years for me since I built an unstable, flipping rocket.

Edited March 3, 2020 by VoidSquid

[AHHans]

Just now, VoidSquid said:

Don't make things too complicated, keep the CoM good ahead of CoT, don't overdo AoA in atmosphere, and everything should be fine.

Yupp. That's how I handle it.
And some of my rockets have effectively a flat pancake as their payload. Those get launched on a steep trajectory so that I get out of the atmosphere early. (E.g. here, and that isn't even the worst offender.)

[VoidSquid]

Yeah, fairings do wonder  

[Garrygirthoak]

Just now, AHHans said:

Yupp. That's how I handle it.
And some of my rockets have effectively a flat pancake as their payload. Those get launched on a steep trajectory so that I get out of the atmosphere early. (E.g. here, and that isn't even the worst offender.)

Not gonna like, i cracked up!

[Guest]

Suggestion @Garrygirthoak: since you're clearly familiar with realistic aerodynamics, I highly recommend that you install the FAR mod. The stock aerodynamics in KSP are pretty primitive and you'll fairly quickly run into stuff working unintuitively -- @AHHans's pancake rockets are just one example.

FAR on the other hand is quite good really; it doesn't model everything (ground effect for example) but generally speaking things behave more or less like you'd expect them to behave IRL.

 

[Garrygirthoak]

Just now, Brikoleur said:

Suggestion @Garrygirthoak: since you're clearly familiar with realistic aerodynamics, I highly recommend that you install the FAR mod. The stock aerodynamics in KSP are pretty primitive and you'll fairly quickly run into stuff working unintuitively -- @AHHans's pancake rockets are just one example.

FAR on the other hand is quite good really; it doesn't model everything (ground effect for example) but generally speaking things behave more or less like you'd expect them to behave IRL.

 

Awesome!! Many thanks for recommendation, i'll give it a try and see how i enjoy it! I'm far from an expert when it comes to realistic aerodynamics.

If i make an effort to try keep a vehicle streamlined i'd like to see the fruits of my labor have an impact on the flight. I've had lots of fun with the game so far, built a base on minnus and mun.

[Garrygirthoak]

4 hours ago, Brikoleur said:

 

Excellent Mod! Now when i start a build with Type A nosecone the COL/COP shifts to the middle of the part. Fairing sizes also shift COP, very nice. Kinda boggles me why this wasn't in the vanilla game.

https://imgur.com/JhQ9T4y https://imgur.com/JhQ9T4y

 

 

 

 

[Guest]

3 minutes ago, Garrygirthoak said:

Kinda boggles me why this wasn't in the vanilla game.

I think it's pretty simple: the vanilla game uses a simple occlusion aerodynamics model that, I believe, uses standard Unity features, whereas FAR is a highly ambitious and pretty complex effort to make a realistic one. Note that it also comes with analysis tools of its own so you can really optimise your aero.

Rather strangely FAR has the reputation of being a "hardcore" mod although IMO it actually makes things easier for the most part, because more intuitive. It does remove a whole bunch of ways you can "cheat" with stock aerodynamics though, so perhaps that's the reason.

In other words it's a simple matter of cost and possibly also expertise, SQUAD aren't real aerospace engineers, they just like to play with rockets.

[VoidSquid]

54 minutes ago, Garrygirthoak said:

Excellent Mod!

No doubt it is, yes.

46 minutes ago, Brikoleur said:

In other words it's a simple matter of cost and possibly also expertise, SQUAD aren't real aerospace engineers, they just like to play with rockets.

This is exactly the reason why FAR is not part of my mods: I'm way more interested in space, maneuvers, and visiting other CBs, than in any atmospheric activities. Sufficient for me that there is an atmosphere I have to take into account when launching my rockets. Never had any interest in planes and jets as well, but since childhood (that's some 50 years ago, lol), I always had a fascination for space - the final frontier  

And that's one of the many aspects I love about KSP (yes, I do complain now and then about SQUAD, but then, who doesn't?), everyone can play as per his preferences, some idiots like me need to optimize their vessels ad infinutum, or have the urge to plant a flag on every CB possible. Others are creating marvelous planes but never go outside Kerbin's atmosphere. Everyone to his own preferences  

Edited March 3, 2020 by VoidSquid