Inflatable heat shield. WOuld <3 to Deflate

[fireblade274]

Being able to deflate the heat shield makes sense and should totally be done. I remember reading the dev notes and seeing the statement that it wont be able to deflate; i immediately told myself "I guess ill never use that". But now I see it, it would fit the job perfectly for one of my large interplanetary planes that can land on the runway, but needs better heat shielding. It will not be able to come in and land like normal with the heat shield inflated, and I built it so I can reuse it for multiple missions: I cant have it inflated all the time.

[Breizhad]

A deflatable shield would be nice, but then it should require an engineer, as does repacking the parachutes.

@fireblade274 For the time being you could place the 10m shield on top of a decoupler, only deploy it if need be and decouple it afterward. It would give you the option of continuing a mission with the parts as they are.

[fireblade274]

10 hours ago, Breizhad said:

A deflatable shield would be nice, but then it should require an engineer, as does repacking the parachutes.

@fireblade274 For the time being you could place the 10m shield on top of a decoupler, only deploy it if need be and decouple it afterward. It would give you the option of continuing a mission with the parts as they are.

To the first point, I completely agree, and maybe even require it to use mono propellant as fuel to re-inflate again

As for using a decoupler, I did think about that, but It would require me to put out and maintain small "cube" like stations of deflatable shields for ships to pick up before making a burn back to Kerbin, and I may very well do that, but I still hope the heatshield is looked at again. To me it just makes sense for it to fold back up again

Perhaps have the heat shield as is be a level 8 tech, and the same thing but with the ability to refold at a cost of slightly more weight?

Edited May 10, 2016 by fireblade274

[Breizhad]

A second one with the ability to refold would get my vote, too. First it doesn't change anything for designs that already have the non-deflatable shield and second it would be consistent to the Photovoltaic Panels which also come in two versions.

[pandaman]

Yes, the idea of two variants, one as it is now,  and the other able to re folded but at a higher technical, heavier and more expensive is the better solution IMO.  Using monoprop as hydraulic fluid to get it to inflate is a neat idea too.

[Superfluous J]

Is deflating a heat shield like this even a reasonable thing to expect? I don't know but it sounds kinda difficult. The heat shield is already neigh-on indestructible and essentially infinitely useful. Being able to stow it and reopen it seems a bit ... much.

Some mod I had installed at one point (I suspect probably Tweakable Everything) added that option in flight.

[Pthigrivi]

Is this easily hackable in the config?

[AlamoVampire]

I like this idea. 2 variants would be nice!

[Superfluous J]

1 hour ago, Pthigrivi said:

Is this easily hackable in the config?

It looks so. Here's the module:

	MODULE
	{
		name = ModuleAnimateGeneric
		animationName = InflatableHS
		isOneShot = false
		startEventGUIName = Inflate Heat Shield
		endEventGUIName = Deflate Heat Shield
		actionGUIName = Inflate Heat Shield
		allowAnimationWhileShielded = False
		restrictedNode = top
		disableAfterPlaying = true
		
	}

I'd guess setting "disableAfterPlaying" to false would do it. If so, this modulemanager config should work:

@PART[InflatableHeatShield]
{
	@MODULE[ModuleAnimateGeneric]
	{
		@disableAfterPlaying = false
	}
}

Note this is totally untested and may not work for several reasons, but I can't imagine it'd hurt your game. I suggest if you try it to start a new sandbox save just to test the heat shield on the launchpad.

Edited May 11, 2016 by 5thHorseman

[Pthigrivi]

Yeah I wondered if that would do the trick... commence testing!

[Superfluous J]

4 minutes ago, Pthigrivi said:

Yeah I wondered if that would do the trick... commence testing!

I screwed up the code. I just edited the post to fix it. Sorry about that.

[DrMarlboro]

2 hours ago, 5thHorseman said:

Is deflating a heat shield like this even a reasonable thing to expect?

No not really. The problem is that it would basically be useless after reentry. They work more like a high speed/high altitude parachute with some ablator on the underside than a heat shield, and I think the one nasa tested (HIAD I believe is what it's called) was only for use on planets with thinner atmospheres like mars. I could be wrong in that aspect, but as far as heat shields go they are single use. 

[fireblade274]

20 hours ago, DrMarlboro said:

No not really. The problem is that it would basically be useless after reentry. They work more like a high speed/high altitude parachute with some ablator on the underside than a heat shield, and I think the one nasa tested (HIAD I believe is what it's called) was only for use on planets with thinner atmospheres like mars. I could be wrong in that aspect, but as far as heat shields go they are single use. 

@5thHorseman

It makes sense heat shields are single use in real life, and I agree it can behave like a high speed high alt parachute, but I would argue this does not make them useless after reentry. From my point of view, this is KSP, where I've used heat shield's and the massive amount of ablator they have multiple times because I can in its reduced physics.

Judging by the way the inflatable heat shield is currently implemented into the game, it does not use ablator. It uses a super heat resistant fabric that does not break down on the exterior like its cousins, but its max core temp is less then that can be held with the standard ablating heat shield. It can take on more heat, but must spend less time in it,  Therefore, looking through the lens of the game and how things are implemented, it makes sense that as long as the inflatable heat shield is not destroyed, it is reusable for reentry and not useless. The only reason it is currently useless for reentry is because it can't be deflated!

And actually since it does have favorable conditions going high speed high altitude, it fits the bill for advanced, large interplanetary SSTO's (and Multiple stage ones too) when coming in from Jool or Eloo so they can save DV by aerobreaking at Kerbin rather then having to slow down with your engines or do an Eve gravity assist first which takes a long time and is difficult to do without KAC or Mechjebs porkchop plots. The only reason they cant be used now in this way its because they can't be deflated once you reach low altitude and will turn your plane into a rock, and good luck trying to jettison it while flying into it also. Adding a large heat shield that can be deflated and reused is beneficial to the game IMO.

Edited May 11, 2016 by fireblade274

[magnemoe]

22 hours ago, DrMarlboro said:

No not really. The problem is that it would basically be useless after reentry. They work more like a high speed/high altitude parachute with some ablator on the underside than a heat shield, and I think the one nasa tested (HIAD I believe is what it's called) was only for use on planets with thinner atmospheres like mars. I could be wrong in that aspect, but as far as heat shields go they are single use. 

Also NASA has no need to make it deflate, In KSP using tugs it would be very smart to let it deflate.
Tankers and other ships can have it fixed on top and brake nose first, for interplanetary missions, one option is to leave the shield with probe and power in orbit and pick it up then returning to kerbin.

Tugs need to push other ships, ships  and need the large docking port on nose as engines don't handle reentry well anymore an deflateable shield on bottom would be perfect. deflate shield and engines work, inflate it areabrake on return to Kerbin. 
 

[Superfluous J]

The question I'm asking isn't *should* it deflate. It's *can* it deflate. It's not a balloon or a tire, and when you're coming down through Eve's atmosphere you should be glad it isn't.

So let's ask the question: What exactly do inflatable heat shields fill with, and can you just suck it all back up when you're done and re-use the shield later?

[magnemoe]

1 hour ago, 5thHorseman said:

The question I'm asking isn't *should* it deflate. It's *can* it deflate. It's not a balloon or a tire, and when you're coming down through Eve's atmosphere you should be glad it isn't.

So let's ask the question: What exactly do inflatable heat shields fill with, and can you just suck it all back up when you're done and re-use the shield later?

Its a bit more advanced than an balloon or tire but work on the same way, note that none of them repack automatically if you remove air. Having an engineer repack, require rank 3.
It also solves the problem with covering engines and landing legs with heatshield. 

[fireblade274]

6 hours ago, magnemoe said:

Having an engineer repack, require rank 3.

That sounds reasonable, have an engineer repack it much like the parachutes (vent out monopropellent and breakdown whatever keeps it sturdy, into folds), though I would say level 5 would be more fitting

[fourfa]

Looks like the tests NASA has done with inflatable heat shields are nitrogen-filled, and packed in a hard vacuum.  Agreed that monoprop could be used for a simple gas generator.  But repacking in atmosphere should require additional mass and expense, for vacuum pumping equipment.   Perhaps extra bulk too, though the stock model seems to have space currently made up of empty mesh that could be filled with machinery.  I'd like to see a mod version that could do this

[AlamoVampire]

Even just to be able to just deflate so a rover or something could drive out/off would be fantastic

Edited May 13, 2016 by AlamoVampire
Forgot some contextual words. Underped myself lol

[Atlas2342]

A single inflate-deflate then? You inflate, after using deflate. After that its basically useless because you can't inflate it anymore....

(so many -flates)

[AlamoVampire]

1 hour ago, Atlas2342 said:

A single inflate-deflate then? You inflate, after using deflate. After that its basically useless because you can't inflate it anymore....

(so many -flates)

Depends on mission needs. Think about say the spirit and opportunity rovers. Single inflate-deflate cycle set were enough. Also consider that a heat shield inflatable or otherwise are typically one and done. Shuttle heat shield was the only mostly reusable do in no small part its tiles.

[RandomUser]

This would be awesome, sure, but it'd have to be made difficult.  I agree that requiring an Engineer, assumably Level 4-5, would make the most sense.  I imagine deflating something as large as that and re inflating it is no easy task, hence the Engineer. 

Though, I think that for a good majority of the players, something like this wouldn't necessarily cross their mind, as most of them likely won't be trying to do a huge run throughout the Kerbol system in one go.  Though, for the more advanced players, this would be incredibly useful. 

I think it really all comes down to whether or not this is even slightly feasible, if it is to go according to actual Physics, without being some completely over engineered design that makes no sense.  Whether or not that is the case though, I think that this would be a great idea to implement. 

[AlamoVampire]

Question, why not make it so we have 2 variants (multiple sizes would not count as thats scaling lol) 1. As we have now. 1. Where deflating = yes and RE-inflation possible with engineer lvl 4-5 only. That seems to fit all of us yes?

[MacLuky]

On 11 May 2016 at 2:23 AM, 5thHorseman said:

I'd guess setting "disableAfterPlaying" to false would do it. If so, this modulemanager config should work:

@PART[InflatableHeatShield]
{
	@MODULE[ModuleAnimateGeneric]
	{
		@disableAfterPlaying = false
	}
}

Note this is totally untested and may not work for several reasons, but I can't imagine it'd hurt your game. I suggest if you try it to start a new sandbox save just to test the heat shield on the launchpad.

 

1

Hmm, I did not get that to work, did anyone else manage to deflate it? If so, can you post the entire patch file? Really like the idea.

Edited August 19, 2016 by MacLuky

[b0ss]

Yes, but it should require some electrical charge to re-compress the air.