Re-nerf the LV-N

[tsinik55]

Shouldn't the title be "un-nerfed" rather than "re-nerfed", which would imply that they need nerfing more?

Yes, my mistake English is not my native language, can be confused sometimes.

Gimme some radiators and cylindrical tanks that are liquid fuel only and I'd be a happy camper again.

Solved the tanks issue with Modular Fuel Tanks. Cannot find a KSP Interstellar-like folding radiators, though.

As much as I don't like mods, looks like in 1.0.x I'm stuck with them. Up to 0.90 I had only MechJeb and Kerbal Joint Reinforcement.

Oh, the nostalgia

[thereaverofdarkness]

LV-N is pretty dead. Its weight gain and the fact that by only using LF it only has half the fuel other engines have mean that its a poor choice to use.

I used to manage 6k dV from my LV-N warships. Now I can only manage 3K using LV-Ns. Other engines give closer to 4 or 5K

And they overheat so you can't even do long burns to make up for their low power.

If tanks could be made LF only then they would be more useful. Weirdly the LF only tank has 160 LF. The LF + O tank has 180 LF and all the oxidiser.

You just have to add more fuel tanks to make up for only using liquid fuel, and also make sure you remove your oxidizer because that adds weight. Doing this, I lost only 20% dV over the old LV-N, not 50%.

You make a good point about the LF tanks, though. Some of them have capacities way too low for their volume, like the Mk1 Fuelselage. The Mk3 fuelselages have more liquid fuel than the same length of Kerbodyne tank, but only a bit more, and all of them have a higher dry mass to fuel ratio than the LF+Ox tanks do.

[arkie87]

The latest patch has brought many problems, and one of them is the lack of normal interplanetary engine.

LV-N, alas, is no more suitable for this role. The weight gain and the inability to use the standard fuel (LF+OX) made it a "fifth wheel"

Therefore, a BIG request to Squad:

1. Return LV-N to its previous state - reduce its weight and allow the use of other types of fuels.

2. If this isn't possible, allow the player to choose the type of fuel in the fuel tanks.

I do know that it's possible to do with mods, but a lot of people prefer to play vanilla KSP, or KSP with minimal modifications (like me).

And, IMO, the ideal option: add the fuel switcher AND some new interplanetary engines (like the Atomic Age by PorkJet) in the official version of the game.

P.S. Again, IMHO: the KSP should be fun, not a hardcore space simulator - we already have the Orbiter for that.

Use module manager to reduce it's mass. Problem solved.

[Mutex]

Solved the tanks issue with Modular Fuel Tanks. Cannot find a KSP Interstellar-like folding radiators, though.

As much as I don't like mods, looks like in 1.0.x I'm stuck with them. Up to 0.90 I had only MechJeb and Kerbal Joint Reinforcement.

Oh, the nostalgia

Yep, I just use this and make all my space ships (other than launchers) only carry LF now.

I know this was intended to get us to use different engines other than the LV-N, but frankly it's had the opposite effect on me. Since I'd now have to carry oxidiser on the ship to use anything else, I can't really justify using anything other than an LV-N now. I'd only ever non-LV-N engines for spaceplanes to do a Laythe landing. Even a Tylo landing is possible with just LV-Ns (as tough as it is).

On top of this, all of the other engines' vacuum ISPs were nerfed too. So... pure LV-Ns it is. Even more so than ever.

[Laie]

I wonder if the Nuclear Engines should be made a difficulty option. There's obviously folks who don't like them for being too good. I guess that house rules just don't cut it: as long as that thing is in the game, there's too much of a temptation to use it. Would it help if people could say they're playing on "hard mode, without reverts or Nervas"?

That said, I'm quite happy with them using liquid fuel only. I'd also wish we had a better system of filling up our tanks; I don't like how the LF+O vs Fuel Only tanks clutter the part list, and I also don't like the adapters being LF+O only. If the contents were tweakable, we could as well have a dedicated nuclear propellant that probably would be nowhere as dense as jet fuel.

Or, Brontoro has pointed out that NTRs could well run on Methane. Denser, a lot easier to store, and still allows for quite respectable ISPs. Talking about which: as all engines in KSP are decidedly worse than real-life engines, how about depressing the Nerva's ISP to somewhere like 600?

And, as I can't repeat this often enough: just make the damn thing bigger. 15 tons, 300 Thrust, Rockomax-sized.

Edited May 10, 2015 by Laie

[Giggleplex777]

A better suggestion would be adding the Atomic Age engines into the game. A LFO nuclear engine would be the LANTR, and if you really want performance you could use the nuclear lightbulb.

[Laie]

A better suggestion would be adding the Atomic Age engines into the game.

I can already hear the outcry. Plenty of people already consider the Nerva to be too good and demand that it needs some nerf or other, and you suggest the Lightbulb (for those who don't know: it's 20t / 450kn / 1500 ISP).

[Starwhip]

"Re-Nerf"? Wouldn't that make it worse than what you're already complaining about?

(Not meant to be aggressive, but I cannot put it any other way...)

As far as I can see, the NERVA is supposed to be both really good and really bad, depending on your ship. It certainly is not the one-engine-for-everything it used to be, and that's a good thing. It makes you rethink your designs and be more efficient. While most pre-1.0 ships using the NERVA will no longer work as planned, 1.0+ ships, taking into account the NERVA's new role, should see a similar level of efficiency.

[Giggleplex777]

I can already hear the outcry. Plenty of people already consider the Nerva to be too good and demand that it needs some nerf or other, and you suggest the Lightbulb (for those who don't know: it's 20t / 450kn / 1500 ISP).

It's supposed to be better than the LV-N. There are many players that think the LV-N is underpowered the nuclear lightbulb should be enough to satisfy them.

Even then, the lightbulb has its own limitations. It's quite heavy and will most definitely be extremely expensive. Also remember that it could be rebalanced if the devs wanted to.

[jshier]

I agree that it should have a lower TWR than most of the liquid fuel engines, and far worse atmospheric performance, since that's such an engine works realistically. But it shouldn't be quite so heavy (it is designed for space travel after all, so some effort should be made to that end), shouldn't have lost gimbaling (nearly all rocket engines have gimbaling, it's been around for decades), and shouldn't overheat when in use, as those engines are self cooling, just like the normal liquid fuel engines.

[Kuu Lightwing]

NERVA should be heavy, because in addition to most parts other rocket engines have it also has a frigging atomic reactor (I think the word "atomic" is more appropriate when you talk about NERVA) as for overheating I actually agree - only NERVA core heats to ridiculous temperatures - the rest of the engine is cooled radiatively. I used to make that mistake too, until the discussion about NERVA in the radiators thread though.

[Wirebraid]

It's still suitable for its role, you just have to change your expectations and approach to it. You just need to use the mark 1, 2, or 3 LF-only tanks for it. Or, just use mods. Frankly, I find it baffling that people say things effectively equivalent to "I know there's a simple and easy solution for what I want, by installing a low risk mod, but I refuse to do that!" Parts mods are all very low risk, if they are just parts, without any new features. There's a large LF-only mark 3 tank, something like 5000 units or so, if memory serves, which is right up there with the Jumbo-64 2.5m tank.

The LV-N was changed to LF-only, because *that's how NERVA engines work*. It was a bug that it used LF+O, the bug was fixed.

Your suggestion is not well founded, and I actively oppose it. Squad, please do not change the LV-N back.

Well, choosing the fuel in the tank does not seem like a crazy idea to me.

[Frozen_Heart]

I can already hear the outcry. Plenty of people already consider the Nerva to be too good and demand that it needs some nerf or other, and you suggest the Lightbulb (for those who don't know: it's 20t / 450kn / 1500 ISP).

Its scary that technology that could potentially be built now is too high tech for a space game.

[worir4]

Its scary that technology that could potentially be built now is too high tech for a space game.

Wow... That is scary. Maybe one day we will have to only use old technology in games because current tech makes it too easy....

[Joonatan1998]

Its scary that technology that could potentially be built now is too high tech for a space game.

If the game had the general fear of nuclear things as a feature then it would be completely balanced.

[Wallygator]

The only thing broken with LV-N engines is the thermal management. Nuclear engines are designed to not over heat. Also, they are not actually intended to be throttled very much at all. Mostly on- mostly off. Frankly, to be more realistic (And usable) the LV-N SHOULD overheat if it is used at any throttle setting other than 100%. The lower the throttle, the faster is should overheat... Yea... I like that!

I would assume a fix to this is likely in the part config.

Perhaps we might ask for a wider selection of LF only tanks, but still, it's easy to cobble together a fuel storage contraption based on the ones in game at present.

[Murph]

The only thing broken with LV-N engines is the thermal management. Nuclear engines are designed to not over heat. Also, they are not actually intended to be throttled very much at all. Mostly on- mostly off. Frankly, to be more realistic (And usable) the LV-N SHOULD overheat if it is used at any throttle setting other than 100%. The lower the throttle, the faster is should overheat... Yea... I like that!

I would assume a fix to this is likely in the part config.

Perhaps we might ask for a wider selection of LF only tanks, but still, it's easy to cobble together a fuel storage contraption based on the ones in game at present.

Yeah, that's all pretty much hitting the nail right on the head. I've not yet used the LV-N enough in 1.0 to be certain about the thermal issues, but it seems like there's enough concern that Squad should be looking at that part of it. The real life Los Alamos / NASA NERVA, which appears to be what the LV-N is attempting to emulate, had thermal management as a major feature and top priority. If anything, I'd say that Los Alamos probably ranked thermal management higher than providing efficient propulsion. So, yeah, it does seem a bit nuts if it has major overheating issues in normal use.

I agree that they are intended to pretty much be either 100% or 0% output, not throttled, but I'm not sure that throttling should cause a huge problem, since the control of the nuclear reaction can be relatively finely controlled by the position of the moderators and control rods/dampers  the control mechanisms for the reactor are not a 100 or 0 only thing. I'll admit that I don't know how NASA's real NERVA would have behaved throttled.

Fuel tanks, yeah, some additional choices of LF-only would not do any harm, but we absolutely can throw together some perfectly reasonable LF-only storage for LV-N tugs right now. It's on the opposite end of the spectrum from "ZOMG, it's broken, Squad sucks!", which is how some people seem to prefer to paint it.

Is it perfect? No. Is it reasonable (with possible exception of thermal issues)? Probably. Is there scope for improvement? Yes. Is it useable today? Yes, with care and creativity, and letting go of "what used to work". Is it useful today? Yeah, I believe so. Should Squad be thinking carefully about the tuning for next release? Absolutely, yes.

[LABHOUSE]

Wow... That is scary. Maybe one day we will have to only use old technology in games because current tech makes it too easy....

Or have a scaled up game.

[youkofoxy]

I think he needs a little more TWR or ISP.

besides solving the overheating problem

Right now Terrier is better for most applications, except when you use an insane amount of fuel.

in fact, it is more advantageous to use multiple Terriers than using a single NERV in Cash and Delta-V term.

my test shows, for a 30 thousand SpaceCraft, Delta V increase of 2576 for the NERV.

in other words, the engine (mainly) turned into scrap metal/museum piece to have just for curiosity.

the only advantage to use it? a bit better TWR, a little more of Delta-V, less wobble and part count (16 agaisnt 40).

P.S.: I regretted using 300 points of science to unlock it, was a very stupid decision.

[Musicrafter]

I like the new LV-N using only liquid fuel. I'd like option 2, but I think there's some nice challenge in cobbling together a suitable fuel tank out of the airplane parts for use on VTOL chemical rockets.

[Renegrade]

Its scary that technology that could potentially be built now is too high tech for a space game.

It's scary that anybody would ever need an NTR in a system that's 1/3 of the size (in terms of delta-v; it's 1/11th physically) as our own~

[Brotoro]

You people are scared easily.

[Murph]

It's scary that anybody would ever need an NTR in a system that's 1/3 of the size (in terms of delta-v; it's 1/11th physically) as our own~

NASA's plans for the NERVA included tugs to take things from LEO to higher orbits. So, it's not so bizarre for them to be used over shorter range.