The 5th Generation Fighter challenge [FAR]

[Cinocal]

Well the single engine wasn't enough for a high top speed so I redesigned for twin turbos. Then I thought, because VTOL. And then I realized, it has too many engines. Back to the hangar!

[Halsfury]

Well the single engine wasn't enough for a high top speed so I redesigned for twin turbos. Then I thought, because VTOL. And then I realized, it has too many engines. Back to the hangar!

More area ruling lol

Also, I've had yet more trouble with super manoeuvrability, the rearward sweep on the wings needs to be overcome!

Also since we've been on the subject of supersonic VTOL, check out this terrifying freak of a plane! the Bell XF-109

It's got death written all over it with 8 jet engines total! 2 in each nacelle, and 4 packed into the rear like C class rocket motors into a cluster booster made by arsonists. Oh and it's a tilt jet, so those nacelles swing through 90 degrees for VTOL, that would be even safer!

Edited June 30, 2015 by Halsfury

[Cinocal]

Without vectored thrust super manoeuvrability is tough. I bet most of these designs would be with more gimbal limit.

[Hodo]

Ok, that looks great, and within challenge rules, I won't hold the VTOL engine to the 50% throttle limitation because it's hard enough as it is.

Now you need to screenshot the various qualification tests and points tests.

EDIT: In other news my design is coming to maturity, I've done some tweaking and reduced the wave drag below 1m^2 which nicely made the aircraft super manoeuvrable at the same time (moving the wing forward and inward)

Now I have only to move the tailplanes out to a point where they provide more control authority in high AoA situations

Thanks I will work on it some this week and fine tune it.... it is still going through testing. But you know how that is. Mach 2 is going to be the REAL challenge with that 50% engine thrust for the turbojet. Seeing as it is still nearly 13tons in its VTOL fuel config, and 15 in STOVL.

[tetryds]

I changed my cargo bay for a jet engine fuel tank and I think I can turn it into an SSTO.

Lol.

Are you waiting to compute the points only after everybody is done?

My missing entries are supercruise speed and range.

The goal I set to myself is to pass 150 points

But I think I should have at least tuned it instead of applying on the first test run, eh, too late.

[Hodo]

So the continuing testing of XF-149A

Today we performed our topspeed run... and it was AMAZING!!!!!

Top speed recorded on a clean aircraft with just cannon ammo was Mach 2.4!

Could have pushed it further but had to turn around due to fuel constraints.

Jeb landed the craft safely back at the airfield peforming a short field landing with ease and stopping it well within the distance of the SPH building.

44min flight on internal fuel and making a top speed run, I believe this craft is capable of over 1hr 45min flight on internal fuel without drop tanks without going to afterburner!

After some minor adjustments to the airframe the XF-149B rolled off the hanger floor for her first test flight.

First I would like to show off our first improvement to the design, the HARM Industries drop tank, it is clean, low drag and shiny!

It holds 251.6units of fuel and did I mention shiny!

The minor changes that reduced the Mach 1 wave section from 1.58 to 1.45 helped a great deal... so much so that the craft accelerated well past its previous top speed of Mach 2.4 to an amazing Mach 3.55!

At Mach 3.2 she meets the 1:1 TWR test, with exactly 1:1 at 182kn of thrust at 18.1tons.

Unfortunately the airframe was damaged in the run, nothing bad, just some heat damage to one of the elevators on the left wing. It was able to supercruise back to the nearest airfield and land safely for repairs.

And just for show, this is the weapons bay of the XF-149B. Which is capable of mounting up to 5 500lb bombs internally or any combination of 5 missiles or stores internally not to mention an additional 3 pair of wing hardpoints! Pictures of the XF-149B with full combat loadout will follow in the coming days along with high G airframe tests and combat performance tests.

Thank you from all of us at HARM Industries!

Edited July 1, 2015 by Hodo

[FourGreenFields]

Talking about the thrust to weight ratio... do you need a TWR of 1 : 1 at 10km, or just at any alt?

[Cinocal]

Any, just has to happen somewhere in the flight envelope.

[Halsfury]

Any, just has to happen somewhere in the flight envelope.

Yeah, the TWR must be 1:1 at some point but it doesn't have to always get that ratio.

Many fighters are designed to work only at certain speed and altitude ranges, for instance the P-47 Thunderbolt was useless below 24,000ft (about 6000m) yet above 24,000 it could outturn everything fielded by Germany and Japan at the time.

The moral is that with a fighter, the engine and it's performance is the limiting factor

[Hodo]

Yeah, the TWR must be 1:1 at some point but it doesn't have to always get that ratio.

Many fighters are designed to work only at certain speed and altitude ranges, for instance the P-47 Thunderbolt was useless below 24,000ft (about 6000m) yet above 24,000 it could outturn everything fielded by Germany and Japan at the time.

The moral is that with a fighter, the engine and it's performance is the limiting factor

How does my entry look so far? Everything ok rules wise?

[Mad Rocket Scientist]

In early tests, my plane reached mach 2 @10,000m with a engine out.

[Dwerto]

This is one of my planes. I call it plane 1 for lack of a better name.

I definitely takes some inspiration from a certain real life aircraft.

here it is going very fast

here it is supercruising with drop tanks. The tanks held 288 liter originally but were only about one third full at this point.

This plane is not exactly the best at supercruising but I think it can do it.

and pulling high G turns

[Hodo]

The XF-149B has gone through some minor revisions and went into full scale combat testing.

Some minor problems were discovered, like its single engine design does limit it to a light weapons load. Which is not a problem because it is a single seat single engine STOVL fighter.

The Jinete was taken out on her test flights today by Valentena.

The loadout for this flight was light even for this craft, but to test weapon deployment and clearance. It performed well, some minor changes were made and the craft performed perfectly afterwards.

Deployment of an AIM-9X Sidewinder from the weapons bay.

After performing some high G turns and putting the craft through its paces we found a minor mechanical issue came up (game bug). And the VTOL engine failed to function on landing so a vertical landing was not possible. But the craft was more than capable of a standard landing even after the VTOL engine failure.

Overall the XF-149B Jinete is turning out to be an excellent addition to the HARM industries stable of aircraft.

Finale tested loadout for the XF-149B is, up to 7000lbs of ordinance, of which 2500lbs can be carried internally.

Edited July 2, 2015 by Hodo

[Azimech]

Here's my entry. Made this a few weeks back in 1.0.2 with standard aero. It's a two seater and therefore a bit heavy. Inspired not by the (in my opinion ugly) 5th generation fighters but the 4th generation. So I installed FAR, set the control surfaces right and the conclusion: flies pretty well!

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I looked at the FAR graphs & stats ... I don't understand any of it. some values red, strange coloured lines looking like a mountain road as seen from above. Is there by now simple documentation anywhere?

Edited July 2, 2015 by Azimech

[FourGreenFields]

I looked at the FAR graphs & stats ... I don't understand any of it. some values red, strange coloured lines looking like a mountain road as seen from above. Is there by now simple documentation anywhere?

http://forum.kerbalspaceprogram.com/threads/121176-Official-FAR-Craft-Repository?p=1949902&viewfull=1#post1949902 <- for the "scary looking numbers" and the graphs.

Green line (your cross section actually) should look like this: https://upload.wikimedia.org/wikipedia/commons/3/33/Sears-Haack.png with the yellow line being as close to 0 as possible. (Both for low Mach 1 drag - above it works slightly different, and below about Mach 0.8 just build them the normal way)

[Halsfury]

I'm back!

Azimech, you should tot up your score, but you can improve with some area ruling, the little nose cone and other 0.5m parts can smooth out your cross section to reduce your transonic wave drag.

This is the reason you're not getting great top speeds. You should be able to do much better than mach 2.3 at 3k.

When you're doing these tests though toggle your gear up in the hangar, it will give a more realistic impression of your performance.

[tetryds]

Welcome back Halsfury.

Did you break my speed record yet?

I was turning my airplane into an SSTO but got bored along the way.

Then I...

This is very effective, I recommend.

Just aim some missile pods down inside of cargo bays.

[Emilio]

This is definitely an interesting challenge.

After a couple of failed airframes I'm wondering if going single engine and very light weight could be a viable option, the thing I'm the most worried about is getting a 1:1 TWR.

Also, I assume the G requirement is here to measure manoeuvrability ? Because in that case, wouldn't it make more sense to measure roll and turn rate ?

[Hodo]

This is definitely an interesting challenge.

After a couple of failed airframes I'm wondering if going single engine and very light weight could be a viable option, the thing I'm the most worried about is getting a 1:1 TWR.

Also, I assume the G requirement is here to measure manoeuvrability ? Because in that case, wouldn't it make more sense to measure roll and turn rate ?

I have a "single" engine light weight fighter in this challenge. It can do everything, it is asked. It is a S/VTOVL aircraft so it is a bit different than the rest. It is agile, fast, and can take off in a VERY short distance, and land vertically if needed or even take off vertically if it is operating a short distance and doesnt need full fuel. The whole aircraft fully loaded with weapons and fuel is only 18.7tons, vertical take off weight is 12.1tons.

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So if I am factoring my points right I think I am at 137.

The XF-149 Jinete can supercruise at mach 1.009 at 10km

Reach a top speed of mach 3.55 @ 12.5km

supercruise with DTs for 2:35min

Pull 12.5Gs, and sustain a 7.5G turn

Droptank capacity is 251.5L each, holds 2 under wings so 503L of fuel.

Not to mention is a single engine, and S/VTOL design.

Has an internal weapons bay to reduce its radar cross section.

Edited July 3, 2015 by Hodo

[Halsfury]

Also, I assume the G requirement is here to measure manoeuvrability ? Because in that case, wouldn't it make more sense to measure roll and turn rate ?

Welcome to the challenge, to mitigate failed airframes I suggest looking over the design of some 5th gen fighters and take it from there, my aircraft is modelled after some of the newest Sukhoi fighters, compare the Sukhoi-30MKI, with my X-32

As to the thing with turn rates, the main thing with using G forces as a measure is that it's easy and tight turning is not a real concern for a fighter, the only concern is that the aircraft doesn't lock up at high speeds and is well designed enough to do what the pilot wants.

@Hodo: Your numbers seem about right. I'll add it to the scoreboard, also what's the name of the aircraft?

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Also I downloaded BD armoury and am very impressed, last time I played with it was version 0.24

I faced off against the new AI in my X-32 versus another drone X-32, and discovered that even though I was raised on combat flight sims, WASD is a horrible way to control a fighter and the drone seemed very adept at tuning the tables on me.

The good news then, is that the X-32 is a good weapons system, the bad news is that I'm incompetent;.;

If anyone wants to put their craft files up here maybe we can take them home and have a BD armoury war-game with them for the ultimate test

Edited July 3, 2015 by Halsfury

[Jeb Likes MOAR]

Do you Get Extra points if you integrate VTOL-STOL engines like the F-35B because i have a design that works,And it meets the Requirements

Because in real life it's a real advantage to be able to lift of of Carriers

[tetryds]

Sorry I won't share mine right now because it's a prototype, not even supermaneuverable yet.

I was trying out some supersonic stunts and want to get them right too.

But the version for this challenge remais unchanged.

I still need to test the endurance of my airplane to sum up all of the points.

[Hodo]

@Hodo: Your numbers seem about right. I'll add it to the scoreboard, also what's the name of the aircraft?

XF-149B Jinete

I may do another aircraft that is a more conventional design.

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Do you Get Extra points if you integrate VTOL-STOL engines like the F-35B because i have a design that works,And it meets the Requirements

Because in real life it's a real advantage to be able to lift of of Carriers

Mine can do that, I dont think there are any extra.

[dogon11]

Consider your challenge accepted.

[Jeb Likes MOAR]

Do you Get Extra points if you integrate VTOL-STOL engines like the F-35B because i have a design that works,And it meets the Requirements

Because in real life it's a real advantage to be able to lift of of Carriers

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