Are fairings useless?

[Xooxer]

I was launching my first three comm satellites for remotetech and was having one heck of a time stabilizing my rocket. I ended up having to place the jumbo airliner wings on as fins, since nothing else was effective enough, and even then, the fairing was producing more lift than the four wings at certain angles/speeds/altitudes. I removed the fairing at one point, but the top stack had so much drag, the effect was essentially the same with or without.

 

I spent days trying to figure out the issue. I t took some time to finally narrow it down to the fairing, but once I did, I was able to adjust it for a stable flight.

 

My fairing's length was the problem. I started it about 2/3 up the rocket. The fairing was straight for most of it's length, and only bowed out and around the package slightly before closing to a very nice aerodynamic point on top. It made sure the tip was streamlined, as I have noticed that blunted fairings fly like bricks.

 

I did not touch the bulb of the fairing at the top. What I did was moved the fairing higher up, as high as I could get it, so it was as short as possible. The bulb and cone were the same, I only removed the straight sections of fairing that were below it. The rocket beneath those sections were just fuel tanks and standard modules, nothing that needed a fairing, but I liked the look of the longer fairing, so that's why I used it in the first place. I didn't think the straight section below the bulb was going to have that much of an affect on the craft.

 

Well, after shortening the fairing to just the essential bulb and cone, my rocket nearly flew itself in a perfect gravity turn. I still needed the giant wings on the back to compensate for the fairing and the length of the rocket, but removing that unnecessary length was what ultimately solved my stability problems.

 

I went through everything trying to figure out why my rocket would flip. CoM, CoT, CoL, velocity, AoA, length of the rocket, TWR, attached and re-attached just about everything that could drag or hang in flight, test, retetst, reretest.... ugh..

 

TL;DR: Shorter fairings are best. If you need one, make it as short as possible.

 

As an aside, has anyone tested whether where you click above the rocket to close the fairing is being used as the topmost point, and if possibly closing the fairing by clicking on the actual visual tip would be a way to workaround the bug? It seems like that might be what's happening, but it'd require some rigid testing to be sure, which, without a testing facility like a wind tunnel, means flight is the only option.

Edited February 1, 2016 by Xooxer
slaying the dran typo demons

[ForScience6686]

On January 20, 2016 at 1:57 PM, Foxster said:

Really fairings are just handy for the lazy or not-so-experienced rocket builder. You can  throw any old stuff together on top of a rocket, stick a fairing around it and call it a rocket. Doesn't work too well though. 

I think that is a rediculous statement.  Most payloads going to space are not streamlined, bulky with sharp edges, as you have nothing to fight once in space.  Plus it's best to keep the payload light, so why waste it on streamlining?  Other factors being heat tolerance and aero forces.  I really wish they would make science and power items able to take damage easier so you had to protect them like what they actually do, with fairings.

Like I've said, I don't experience these control issues, and many that I see that do, experience it while off prograde.  But since your fairing tends to be bigger than the rocket body shouldn't you assume it will impart more body lift?  And since that lift is coming from the end of the lever, should it not be expected to have a lot of force?

I'm sorry, but I'm just tired of the fairing bashing.  I'm just glad to have them now.

[p1t1o]

Fairings causing a loss of stability is NOT a bug. IRL, fairings are not at all used for stability and most real rockets are flown unstable, they are actively stabilised with thrust vectoring.

Fairings are there to protect the payload, that is pretty much their entire function. As it happens however, there isn't much in KSP to protect your payload from, unless you favour very energetic launches.

Fairings are working properly IMHO, you just need to learn how to fly 'em (again).

Difficulty is not a bug.

[Tex_NL]

15 minutes ago, p1t1o said:

Fairings causing a loss of stability is NOT a bug. IRL, fairings are not at all used for stability and most real rockets are flown unstable, they are actively stabilised with thrust vectoring.

Fairings are there to protect the payload, that is pretty much their entire function. As it happens however, there isn't much in KSP to protect your payload from, unless you favour very energetic launches.

Fairings are working properly IMHO, you just need to learn how to fly 'em (again).

Difficulty is not a bug.

Sorry to burst your bubble of denial but it IS a bug. If you had bothered to check the aerodynamics vector overlay you would have known the body lift vector on the stock fairings is placed too far in front. It is so far to the front in fact that is is outside the fairing itself.
Next time please check the facts or don't bother to weigh-in at all.

[p1t1o]

1 hour ago, Tex_NL said:

Sorry to burst your bubble of denial but it IS a bug. If you had bothered to check the aerodynamics vector overlay you would have known the body lift vector on the stock fairings is placed too far in front. It is so far to the front in fact that is is outside the fairing itself.
Next time please check the facts or don't bother to weigh-in at all.

I did not actually realise that, my bad. Though fairings have been adversely affecting stability long before 1.05 came along.

Is it definitely a bug with fairings, or could it be a bug with the aero overlay?

It is still true that a realistic fairing should (in most cases) de-stabilise your rocket.

Edited February 2, 2016 by p1t1o

[bonyetty]

2/1 X the height of a fairing is significantly different to 1/2 X height of a fairing when applying fairing lift. 

 

[Warzouz]

@p1t1o, this bug is already identified by Squad for few weeks. It appeared in 1.0.5 and wasn't present in 1.0.4. I'm quite amazed the didn't fixed it. I'm now nearly unable to launch most of my usual rocket with fairing. Sure there is the exploit of setting the fairing backward so the stability would be increased. But I don't like to use part for what they're not designed to.

I only hope they don't forget to fix that bug in 1.1...

[nobodyhasthis2]

13 hours ago, p1t1o said:

Is it definitely a bug with fairings, or could it be a bug with the aero overlay?

It is still true that a realistic fairing should (in most cases) de-stabilise your rocket.

It is definitely a bug with fairings. Pass that point that I am forbidden by ethics to comment on your belief system about realistic fairings.

13 hours ago, Warzouz said:

@p1t1o, this bug is already identified by Squad for few weeks. It appeared in 1.0.5 and wasn't present in 1.0.4. I'm quite amazed the didn't fixed it. I'm now nearly unable to launch most of my usual rocket with fairing. Sure there is the exploit of setting the fairing backward so the stability would be increased. But I don't like to use part for what they're not designed to.

I only hope they don't forget to fix that bug in 1.1...

As annoying as it. It happened in response to a change elsewhere. The bug is well understood and was fixed in the long running patching mod by @Claw. Having pointed this out Squad will officially fix it eventually.

Until then we have a patch or a completely new alternative by using Procedural Fairings.    

[Delta_8930]

The Old School Fairings mod fixed it up for me. I usually don't use the stock procedual fairings. I prefer AIES, KW, or e-dog's procedual fairings. 

[p1t1o]

On 2/3/2016 at 2:03 AM, nobodyhasthis2 said:

Pass that point that I am forbidden by ethics to comment on your belief system about realistic fairings.

Oh? Phew!

 

[nobodyhasthis2]

15 minutes ago, p1t1o said:

Oh? Phew!

Yes and in other news Claw is now staff 

[wumpus]

On 2/3/2016 at 9:03 PM, nobodyhasthis2 said:

As annoying as it. It happened in response to a change elsewhere. The bug is well understood and was fixed in the long running patching mod by @Claw. Having pointed this out Squad will officially fix it eventually.

Luckily for us, Claw was just hired as an official developer.  Hopefully that means that bugfixes like this *will* show up in the next official release.

[nobodyhasthis2]

2 hours ago, wumpus said:

Luckily for us, Claw was just hired as an official developer.  Hopefully that means that bugfixes like this *will* show up in the next official release.

I know look at my comment on the announcement threat just after the news broke.. Seems my early statement here tuned out to be a pretty be good prediction that Squad would recognize his bug fixes. Looks like we be getting there even quicker now  

Edited February 5, 2016 by nobodyhasthis2