The 5th Generation Fighter challenge [FAR]

[tiffanyw]

I mean that the B9 wings are a flat board from front to back, but it's alterable from side to side. I found myself unable to eek out the same performance from the B9 wings as I was able from the deltas.

[Hodo]

Adjustable landing gear is already on the list.

My primary concern is I may not be able to use the cockpit I have been using, and there is no way to approximate its shape in stock.

Speaking of which, this is my current project: MRF-3* Black Mamba

http://imgur.com/a/6jG3f

I created this particular album for the Adjustable landing gear thread in hopes they can help resolve this bizarre wobble I'm getting from the landing gear.

The wobble is because the rear gear are not exactly level. The camber on them is off just a hair. Try hitting the auto-alignment button in the gear when you are done moving them. Sometimes you may need to rotate with the stock rotation system.

[CrisK]

Adjustable landing gear is already on the list.

My primary concern is I may not be able to use the cockpit I have been using, and there is no way to approximate its shape in stock.

Speaking of which, this is my current project: MRF-3* Black Mamba

http://imgur.com/a/6jG3f

I created this particular album for the Adjustable landing gear thread in hopes they can help resolve this bizarre wobble I'm getting from the landing gear.

Heheh. This looks so goofy. I love it.

Halsfury, I don't really like the limit on mods. It means that we can't use 3rd party cockpits, or variable wings using infernal robotics.

[Halsfury]

@HengeProphet

In response to the whole thing about stock wings over performing, that actually explains a lot, I found that throughout the development of the Su-27 that there was just too much lift generated from those wings.

I like that the asymmetric lift bug has been kicked to the curb, hopefully with less lift the Su-27 will be a better performer and be able to use the front fuel tank without making the plane tail heavy.

- - - Updated - - -

Heheh. This looks so goofy. I love it.

Halsfury, I don't really like the limit on mods. It means that we can't use 3rd party cockpits, or variable wings using infernal robotics.

I don't mind having those mods either, just do as you're doing and bring the mods you want to my attention.

I'll probably add the mod unless I see potential for exploiting the rules with one of them

- - - Updated - - -

Could you add Baha adjustable landing gears to the mod list? And maybe Procedural Parts although I can do without that if I have to.

Procedural Parts might be a little too far, I want you to have some explosions at least

Baha adjustable landing gear has been added but just as "Adjustable Landing Gear"

[TheHengeProphet]

The wobble is because the rear gear are not exactly level. The camber on them is off just a hair. Try hitting the auto-alignment button in the gear when you are done moving them. Sometimes you may need to rotate with the stock rotation system.

Unfortunately, camber is not the issue here. I get the same performance with the camber being up to five degrees off, though I haven't tested past that. The pictures show that the camber is off by a fraction of a degree. A fraction so small I can't actually get closer to it with the adjustment resolution KSP allows.

Heheh. This looks so goofy. I love it.

The cockpit does look kinda goofy, but that sharp shape is great for reducing the wave drag area. It does cause the plane to be a little squirrely under high pitch at low velocity, but if you've gone that far you're probably at risk of stall anyways.

I haven't messed around with Procedural parts... been thinking about it, but it's just yet another mod to install, haha.

So, I actually have a rule with this plane that if there is a significant quantity of parts clipped into an individual part, I can't use it for fuel storage. As such, the engine nacelles and the wings are currently the only holders of fuel, allowing the rest of the area to be used for equipment. This nets me around 500L of fuel, which isn't that much less than an F-16 carries.

When you say the plane should be able to pull a 9g turn in sub-sonic flight, do you mean that so long as it's not going mach 1, or should it be below transonic speed as well? Transonic speed is around 275m/s at sea level.

[CrisK]

Here's a little something that I built for the proposed stealth / reconnaissance category:

Javascript is disabled. View full album

Edited August 28, 2015 by CrisK

[TheHengeProphet]

That's cool that you approximated and F-117, but I'm pretty sure they were simply not a fighter. I'm curious if yours is capable of competing in an air-to-air combat.

[CrisK]

That's cool that you approximated and F-117, but I'm pretty sure they were simply not a fighter. I'm curious if yours is capable of competing in an air-to-air combat.

In short, no. It's not capable of competing with any of the fighters. Hals mentioned adding new categories for reconnaissance planes, utility planes, etc.

[Zixor]

Does that F-117 fly like the real thing? That is to say, is it horribly aerodynamicaly unstable like the real thing?

[CrisK]

Does that F-117 fly like the real thing? That is to say, is it horribly aerodynamicaly unstable like the real thing?

I plead the 5th.

Yes. It flies like a brick.

[TheHengeProphet]

Now I'm wondering if there is some way to detect for a craft's radar cross section, versus both active and passive radars.

Oh, I forgot to provide my assessment of the Su-27! It is really quite nice to fly. Heavy (12t dry!) and slow, but quite nimble. Okay, I ran a couple dogfights between the Su-27 and one of my test planes. The Su-27 was unable to compete, simply because it couldn't get up to speed. Eventually, as a test, I set its engines at 100% thrust (it was still having some trouble at 75%), and it began to function quite well. It is ridiculously maneuverable, and the AI can only be trusted with about 65% control at best, and about 40% control at low speeds.

If the intention is to let the AI dogfight to find a winner, I suggest people tune their aircraft and AI parameters for best one-click use (turn on and go).

Edited August 29, 2015 by TheHengeProphet

[Halsfury]

Now I'm wondering if there is some way to detect for a craft's radar cross section, versus both active and passive radars.

Oh, I forgot to provide my assessment of the Su-27! It is really quite nice to fly. Heavy (12t dry!) and slow, but quite nimble. Okay, I ran a couple dogfights between the Su-27 and one of my test planes. The Su-27 was unable to compete, simply because it couldn't get up to speed. Eventually, as a test, I set its engines at 100% thrust (it was still having some trouble at 75%), and it began to function quite well. It is ridiculously maneuverable, and the AI can only be trusted with about 65% control at best, and about 40% control at low speeds.

If the intention is to let the AI dogfight to find a winner, I suggest people tune their aircraft and AI parameters for best one-click use (turn on and go).

Yeah, I faced off with the hornet in that thing with Goldstein, and one thing the update does not change is weight.

It is roughly the "right" weight, but the F-18 packs just as much thrust into a much smaller airframe (really this is completely unrealistic in reality they're both about the same weight)

I eventually shot down the hornet but that was largely because the AI is rather dumb, though one time he took an elevon straight off the plane in a gun pass.

The one thing I would advise if fighting against it is never to get in front of that 30mm cannon. It's game over if only a few rounds actually hit.

@Crisk that's one of the toughest things to do in FAR I'm pretty sure. God she's ugly, but that's all the computing power they could manage in the 80's for determining how low the radar cross section would be.

It's really interesting from a design perspective since it's really a physicists "spherical horse" simplification of a low radar observability aircraft which an airframe was then built around.

Edited August 29, 2015 by Halsfury

[TheHengeProphet]

Yeah, facing off against it several times, if I managed a "click and go" control-ability set for both my MRF-2 and your Su-27, my plane was the consistent victor. However, if I adjusted each plane's control value mid-flight, the Su-27 became more maneuverable than mine, but couldn't keep up on speed, and it became a much more even match. That 30mm gun is a beast (having taken out my cockpit several times), and your Su-27 is a tank, having gotten hit by a sidewinder and losing nothing but some missiles and its air intakes!

I was running these dogfights at 100% thrust for both craft, with a max speed set at ~400m/s as it was much more interesting that way.

Now I need to try my craft vs some other craft!

Update: The F-16 proved too unstable, even under 30% control value, preventing it to perform even basic combat flight without fatally stalling.

The Rafale also proved quite unstable, but was still able to function. Unfortunately, after three flights, each ended with an AIM-120 up the rear, despite chaff.

The F-18 proved an incredibly even match with each plane allowed full control authority. Incredibly, even with one of its wings shot off, the F-18 continued to haphazardly maneuver and remain flying, taking shots at the other craft when possible! However, with its combat maneuverability compromised, it was only a matter of time before it was finished off. Now to continue on for a best-of-three... I'm almost daunted by this, considering each of the matches with prior craft took about 10 minutes each, and against the F-18, even the first lasted almost a half hour.

Okay, things started moving faster when I upped max thrust to full. I'm not sure I can declare a clear winner here. Both managed to destroy each other 2/7 times (both died from combat-related injuries), and killed the other unscathed once. One of the double-death scenarios involved the F-18 shooting off the tips of the MRF's wings, and the MRF continuing to fly as a lifting body and getting a lucky shot with the 20mm as the F-18 blew past, causing it to careen into a mountain. The F-18 managed to rend itself in twain during a daring maneuver once, and the MRF-2 ran out of fuel once. One fight, a whole lot of nothing happened, and the MRF-2 performed this insane climb maneuver and went into space, eventually re-entering and returning to safe flight almost 100km away in what I would consider an incredible disengage action. I suppose this is one of the reasons we need to keep those engines throttled down, heheh. In end, though, I might have to give the combat edge to the F-18 on endurance standards, and very slightly in the maneuverability departments, even though the MRF-2 has the advantage in speed, and also maybe stealth, if that matters...

Edited August 29, 2015 by TheHengeProphet

[Halsfury]

Yeah, facing off against it several times, if I managed a "click and go" control-ability set for both my MRF-2 and your Su-27, my plane was the consistent victor. However, if I adjusted each plane's control value mid-flight, the Su-27 became more maneuverable than mine, but couldn't keep up on speed, and it became a much more even match. That 30mm gun is a beast (having taken out my cockpit several times), and your Su-27 is a tank, having gotten hit by a sidewinder and losing nothing but some missiles and its air intakes!

I was running these dogfights at 100% thrust for both craft, with a max speed set at ~400m/s as it was much more interesting that way.

Now I need to try my craft vs some other craft!

Update: The F-16 proved too unstable, even under 30% control value, preventing it to perform even basic combat flight without fatally stalling.

The Rafale also proved quite unstable, but was still able to function. Unfortunately, after three flights, each ended with an AIM-120 up the rear, despite chaff.

The F-18 proved an incredibly even match with each plane allowed full control authority. Incredibly, even with one of its wings shot off, the F-18 continued to haphazardly maneuver and remain flying, taking shots at the other craft when possible! However, with its combat maneuverability compromised, it was only a matter of time before it was finished off. Now to continue on for a best-of-three... I'm almost daunted by this, considering each of the matches with prior craft took about 10 minutes each, and against the F-18, even the first lasted almost a half hour.

Okay, things started moving faster when I upped max thrust to full. I'm not sure I can declare a clear winner here. Both managed to destroy each other 2/7 times (both died from combat-related injuries), and killed the other unscathed once. One of the double-death scenarios involved the F-18 shooting off the tips of the MRF's wings, and the MRF continuing to fly as a lifting body and getting a lucky shot with the 20mm as the F-18 blew past, causing it to careen into a mountain. The F-18 managed to rend itself in twain during a daring maneuver once, and the MRF-2 ran out of fuel once. One fight, a whole lot of nothing happened, and the MRF-2 performed this insane climb maneuver and went into space, eventually re-entering and returning to safe flight almost 100km away in what I would consider an incredible disengage action. I suppose this is one of the reasons we need to keep those engines throttled down, heheh. In end, though, I might have to give the combat edge to the F-18 on endurance standards, and very slightly in the maneuverability departments, even though the MRF-2 has the advantage in speed, and also maybe stealth, if that matters...

disengage to space? that's why we need the new engine so badly, it's not about thrust limitations it's about when the thrust starts to taper off and in KSP this seems to be near orbital speed.

It's good that all the aircraft are fairing well as dogfighters, the Su-27 is a tank, I had the same thing happen to me where I flew head on towards the AI and he started to fire missiles, sure enough they all blew up in the vicinity of the Su-27 but only removed missiles from the wings.

I don't know what happened to the F-16 though, it might have just got too much authority for it's own good, it's quite slow however as a single engine fighter it's mean't to be cheap and maybe shouldn't even be in the challenge (I just posted it cause it was cool)

[TheHengeProphet]

Even on half thrust, I had my plane do the same thing in another battle, but it only made it to 40km, rather than the 72. The plane itself has a not-so-unrealistic flight ceiling of around 17km, because it has so much relative wing area, where the engines will cut out around 22km (but at half throttle, they don't provide a whole lot of thrust).

I think the F-16 needs more forward mass, or less rearward mass... I'll do some testing to see if I can make it viable. Even under 100% thrust value, it just couldn't stay level.

I would like to know what your thoughts are on reaction wheels being active. I personally deactivate then on any plane I build, but that's because I don't think fighters should have magic forces giving them extra control authority (though it is really nice when the thing stalls out).

Now, if I can only figure out this landing gear issue, things will be just peachy...

[FourGreenFields]

Now, if I can only figure out this landing gear issue, things will be just peachy...

Just guessing: The plane yaws left and right, which gets worse and worse, once you pass a certain speed and/or apply brakes? Possibly causing the thing to roll and then crash?

If it only happens when applying brakes, reduce break torque. Either the breaks are causing flex, or your nose gets pushed down, leading to instabilities. (No warranty on me being correct with that; can be into flying things, can not be into cars)

Else I don't know. I usually manage to fix that, but I'm not sure how.

In both cases it usually helps to pull on the elevator from my experience. Not allways helps enough, but haven't seen that make things worse.

[TheHengeProphet]

Actually, pulling up doesn't make it better or worse, and no, the back legs start jumping, basically. I've tried reducing the brake torque, but then the plane just doesn't stop. I think I need to pull this into a fresh install...

Anyways, I had my MRF-2 face off against the MRF-1B... At standard half-thrust flight, the 1B would constantly scrub all its speed out, and never get over 200 m/s. However, at full throttle, and given 40% control, it outperformed the 2 every time... Really not sure how to feel about this. However, if stock wings are overperforming, it makes some sense.

Also, I noticed something interesting: B9 wings have a temperature tolerance of 2000, while stock wings have one of 2400, which explains why planes built with stock wings can weather missiles. On multiple occasions, the MRF-1B was hit by an AIM-120, suffered nothing more than turning red, and proceeded to turn around and wreck the MRF-2 with vulcans.

[FourGreenFields]

Do you touch down without slipping and without being banked? That would definitly cause some problems I'd say.

[CrisK]

@TheHengeProphet I don't like reaction wheels because they can cause the plane to snap itself in half by performing maneuvers that are not physically possible. However, I tend to clip an MK2 drone core into my planes' bodies because the core includes a battery, and it can track targets.

Tonight I tried to design the best small 5th gen fighter that I could, not based on any pre-existing designs. Here's what I came up with:

Javascript is disabled. View full album

I call it the C-R Silver. It's capable of sustained Mach 1.4 supercruise above 8k, vertical climbs, able to reach Mach 2 with ease.

I used FAR's flight analysis tools to perfectly balance the wings so that it's capable of extremely tight turns, it has incredible AOA stability. That took a lot of fiddling. It's supermaneuverable. It's actually the most acrobatic fighter I've flown in KSP. I took a few screenshots of it performing cobras, loops, spins, etc.

It has a large internal bay at the bottom with up to 6 large missiles, and two smaller ones on the side that can carry 2-4 smaller missiles (2 sidewinders, 4 hellfires, etc.)

I think I'll hold off on designing any new planes for a while and enjoy flying everyone's creations. The F-16 is great in my eyes. The Su-27 flanker still needs some work, but it's my favorite flanker design, and I think it's the flanker to beat. Strictly in terms of how well it flies, I think that it's the best flanker on the forums. I want to play around with the Wheel Wobble if Henge posts the craft file. Hint hint.

[TheHengeProphet]

I'll get around to it... I've been working on getting its stability in line.

Here is the version without hard points, vulcan only, and mod required for the cockpit.

https://dl.dropboxusercontent.com/u/11337184/MRF-3B%20Black%20Mamba.zip

[DiamondHawk427]

Is it ok if engines stightly merge? for making crafts such as f-104, they have very close engines

[TheHengeProphet]

Is it ok if engines stightly merge? for making crafts such as f-104, they have very close engines

Not sure... Unfortunately, smaller engines aren't available without tweakscale, which would make the design you're wanting feasible.

Okay, so... I discovered the braking issue. The light adjustable landing gear will begin to bounce when braking if the braking torque is anything over the default 55. I will upload an updated version shortly.

--Update--

The last link provided will take you to the most recent version of the MRF-3.

I've been working on it quite a bit, as it is now capable of landing, and has an additional airbrake mid-airframe. At this point, I wouldn't say it is the most capable fighter; however, it is capable of almost any role you'll need of it, hence the MRF designation (MutiRole Fighter). It is capable of a 9g turn in the transonic range, and exceeds at speeds of around 350m/s-400m/s. Current maximum payload is unknown. Maximum AoA is about 21° (above 20° is not suggested), yet the craft is still capable of control up to nearly 23°. It has yaw instability under mach speeds, but becomes fully stable after. It weighs 9.6t dry, and 12.5t carrrying 496.5L of fuel, and 1300 rounds of 20mm ammunition. Maximum LO weight to be determined. After testing, I would say it has a maximum operational altitude of ~17.5, capable of pulling 3g turns exceeding mach 3. Capable of reaching Mach 3.3 in level flight at an optimal cruising altitude of 16700m without use of afterburners. A safe operational range of 180km (Maximum range of 250km, or 500km round trip) without external fuel stores, and not using fuel stores in clipped parts.

Top speed has not been determined, as it involves melting.

This data is particularly important if we're thinking about looking at stealth craft, as not using afterburners becomes important for maintaining a low thermal signature. That entire run totaled 0:20:30 (man these engines are inefficient), and could have been done more efficiently if afterburners were used to get up to altitude and speed before cruising, but I really just wanted to see how fast and high I could go without using afterburners. I will likely continue to modify the plane, possibly to be lighter and more maneuverable. The optimal cruising altitude was determined by testing what altitude would allow the thrust and drag to be at the best balance. I'm sure the math could be done on it, but I'm too lazy to figure that out.

Unfortunately, the outer wing sections are what stall, and if I made it a singular piece, I'm sure I could achieve better results... Also, the plane is likely to require a major redesign when 1.1 rolls out, as the profile of the Panther engine is much different, and will likely modify drag behaviour.

Further testing, and repeated dogfights have shown the plane to be stupid maneuverable; particularly at speeds over 320m/s. The AI tends to try to stall it out, but once it gets up to speed, it's a bit ridiculous. Soon, I'll load it up with hardpoints, so it can be equipped for proper combat, but these initial tests were done as vulcans only dogfights against my old adversary: the FA-18J. At speeds of 400m/s and up, the MRF-3D won every time. At speeds of 350m/s and below, there was no point at which the FA-18J could get the MRF-3D in its sights long enough to shoot before the MRF-3D banked out of the way; however, they were both so unwilling to slow down that it just became this strange skydance until the MRF-3D ran out of fuel or they ran into eachother.

I may need to change its reporting name to Stingray, because that's what it really looks like when flying about.

Edited August 31, 2015 by TheHengeProphet

[Halsfury]

Is it ok if engines stightly merge? for making crafts such as f-104, they have very close engines

Yes engines can have slight overlaps, but just so you know, the F-104 only had 1 engine.

[TheHengeProphet]

Speaking of the F-104, it weighed less than 10t fully loaded. Perhaps a weight restriction isn't specifically necessary here; especially if we consider that these are supposed to be Gen5 fighters, which could well be lighter than they were back in the 60s.

[Halsfury]

Speaking of the F-104, it weighed less than 10t fully loaded. Perhaps a weight restriction isn't specifically necessary here; especially if we consider that these are supposed to be Gen5 fighters, which could well be lighter than they were back in the 60s.

It is a 60's era interceptor, although you might think that all our modern kevlar and carbon fibre stuff has made planes lighter, in fact, the general trend seems to be increasing engine power, increasing wing loading, and increasing payload.

For example the P-51D Mustang weighed 5.4 tons at maximum loading, and the B-25 Mitchell (a medium bomber) weighed only 15 tons.

the F-22 Raptor, by contrast, weighs roughly 30 tons with a medium load out, and 38 tons at maximum.

So 2 things are evident. Firstly, now you know why a wheels up landing isn't a great option for a modern fighter and why pilots always use the ejection seat when their planes get into trouble.

Secondly, it becomes really obvious that the more engine power that can be harnessed, the fatter the aircraft gets, merely because a larger aircraft can store more payload.