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The 5th Generation Fighter challenge [FAR]


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Here's a Bird of Prey with a different layout and more accurate wing design, and a completely innacurate intake design. :sticktongue: It's now stable until 60* AoA, and capable of stall maneuvers (supermaneuverable).

[imgur]DFOA5[/imgur]

Here's a new F-22 style plane. I had to sacrifice a small amount of performance for the sake of appearance. It has slightly worse performance than the E-USAF, but it's still incredibly maneuverable.

[imgur]IY0hQ[/imgur]

I tossed screenshots of a cobra maneuver and tight loops into the album. (Reaction weels have to be disabled for these kinds of maneuvers.)

I tweaked the E-USAF so that it has lower drag, even with external drop tanks. Here's the E-USAF with full drop tanks and missiles performing some silly maneuvers at sub-1000m altitudes. (Both the E and F planes weigh about 22k.) The E can perform a cobra maneuver at 50m above sea level without stalling into the ocean.

[imgur]l7HuD[/imgur]

[img]http://i.imgur.com/wWRLslj.png[/img] Edited by CrisK
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Instable at subsonic speeds, but nothing SAS can't handle (and I consider the KSP SAS to be BS, so it really isn't bad). Once you pass Mach 1, it's stable.
Going to upload soon™ (possibly modded with airbrake or whatever).

Edited by FourGreenFields
The changes done to the forum removed the album, and messed with the "™"
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@FourGreenFields Nice. You should be able to improve the maneuverability by adding small chines or strakes leading into the wings, and shifting the rear wings back a bit. I played around a lot with similar wing designs when I was designing my YF-23 replica, so I think that it's absolutely possible to make a design like yours supermaneuverable and stable to an AoA of about 50 degrees. It just takes some tweaking.

If you post the craft file, I bet that I could tweak it slightly to make your fighter one of the most maneuverable in the thread.
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[quote name='CrisK']@FourGreenFields Nice. You should be able to improve the maneuverability by adding small chines or strakes leading into the wings, and shifting the rear wings back a bit. I played around a lot with similar wing designs when I was designing my YF-23 replica, so I think that it's absolutely possible to make a design like yours supermaneuverable and stable to an AoA of about 50 degrees. It just takes some tweaking.

If you post the craft file, I bet that I could tweak it slightly to make your fighter one of the most maneuverable in the thread.[/QUOTE]

Meh. It's allready near-neutral pitch stable at subsonic speeds. Extending the leading edge near the root would make it worse.
Can't shift the stabilizers too much, or it'll ruin area ruling. Can't sweep 'em either, or I have to deal with [I]twice[/I] the wave drag.


On a more positive note, I found that it can reach Mach 2 at 10km without afterburner :)
[IMG]http://i.imgur.com/VgWseHE.jpg[/IMG]

Anyway. Uploaded it now. [EDIT: Deleted because edited craft to be able to do post stall manoeuvreing, [URL="http://kerbalx.com/crafts/7510"]new craft here[/URL]]


PS: Wave drag might be higher if you're using different settings btw. Full drag, strict area ruling, I got better results than with default settings... Didn't check the version I uploaded yet though. Edited by FourGreenFields
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@FourGreenFields, Some minor adjustments and she's supermaneuverable. Ignore the FAR numbers and try flying her. :P She's stable up to an AoA of 58* at which point she goes into a full stall, but recovers immediately. You can perform 180 degree turns, cobra maneuvers, tight loops, etc.
[URL="https://www.dropbox.com/s/h020ameuc28llol/P%2024%20Goshawk%20V2.craft.zip?dl=0"]
Dropbox link to craft file[/URL].

I'm not going to modify it further since it's your design, but this platform has the potential to be a real performer. I bet that you could increase the AoA performance to about 65 degrees, lower the wave drag, and increase durability by shifting the wings around until you find a magic spot, adding struts, etc.
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[quote name='CrisK']@FourGreenFields, Some minor adjustments and she's supermaneuverable. Ignore the FAR numbers and try flying her. :P She's stable up to an AoA of 58* at which point she goes into a full stall, but recovers immediately. You can perform 180 degree turns, cobra maneuvers, tight loops, etc.
[URL="https://www.dropbox.com/s/h020ameuc28llol/P%2024%20Goshawk%20V2.craft.zip?dl=0"]
Dropbox link to craft file[/URL].

I'm not going to modify it further since it's your design, but this platform has the potential to be a real performer. I bet that you could increase the AoA performance to about 65 degrees, lower the wave drag, and increase durability by shifting the wings around until you find a magic spot, adding struts, etc.[/QUOTE]

No offense, but you just increased wave drag tenfold (well, eightfold anyway), just for supermanoeuverability. (Using strict area ruling and full drag. But even on default it's more than twice the previous wave drag)
Its slower with afterburner, than the previous version without afterburner. That might be a tad too much to lower back down, just by shifting the wings around.

PS: Just managed to modify it to be able to do a cobra manoeuvre. Extended the leading edge near the wing root a bit (way less than on your version), and added a spoiler function to the elevator (25.5°). Can now pull up until it stalls, and remain fully controllable (cobra, flying backwards, whatever). Works at up to Mach 0.5. Edited by FourGreenFields
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[quote name='FourGreenFields']No offense, but you just increased wave drag tenfold (well, eightfold anyway), just for supermanoeuverability. (Using strict area ruling and full drag. But even on default it's more than twice the previous wave drag)
Its slower with afterburner, than the previous version without afterburner. That might be a tad too much to lower back down, just by shifting the wings around.[/QUOTE]
Wave drag and area ruling are things that you worry about after you've finalised the flight performance and overall design. :wink:

The wave drag of the E-USAF I posted a page back is lower than that of the P 24 Goshawk. The area is also lower than the P 24. That's with 4 missiles, 5 small hardpoints, a large drop tank, roughly 55% more mass, close to twice the wing area, etc. It didn't start off that way; it took a lot of precision tweaks to improve the performance to that level.

I think that you're focusing too much on wave drag and area ruling while designing. You should be able to get that design down to 0.5. But before you worry about that, make sure that the plane flies well.

It's slower because it has a heck of a lot more fuel. Empty the wings to lower the weight down to what it was before. :wink:
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[quote name='CrisK']Wave drag and area ruling are things that you worry about after you've finalised the flight performance and overall design. :wink:

The wave drag of the E-USAF I posted a page back is lower than that of the P 24 Goshawk. The area is also lower than the P 24. That's with 4 missiles, 5 small hardpoints, a large drop tank, roughly 55% more mass, close to twice the wing area, etc. It didn't start off that way; it took a lot of precision tweaks to improve the performance to that level.

I think that you're focusing too much on wave drag and area ruling while designing. You should be able to get that design down to 0.5. But before you worry about that, make sure that the plane flies well.

It's slower because it has a heck of a lot more fuel. Empty the wings to lower the weight down to what it was before. :wink:[/QUOTE]

You have to worry about everything when you start designing a plane, and want it to be good. Stability, manouevreability, low weight, low drag at all speeds, weapon position, etc. etc. etc.
And even 0.5m² would be twice the previous wave drag. There has to be a better solution, even if it means redesigning the whole thing. Which I didn't have to, as the edit in my previous post shows.


PS: Seems the added elevator deflection doesn't do all that much. Can allready initiate any kind of post-stall maneuver at Mach 0.4. Edited by FourGreenFields
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[quote name='FourGreenFields']You have to worry about everything when you start designing a plane, and want it to be good. Stability, manouevreability, low weight, low drag at all speeds, weapon position, etc. etc. etc.
And even 0.5m² would be twice the previous wave drag. There has to be a better solution, even if it means redesigning the whole thing. Which I didn't have to, as the edit in my previous post shows.[/QUOTE]
I don't want to argue with you. I enjoy your design, and I found it fun to play around with it. I'll end my feedback there. :wink:
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Well, I got it to do post-stall-manoeuvres at up to Mach 0.5 without increasing wave drag too much. Can also pull more AoA at subsonic speed before stalling. Stability seems to be roughly the same as before.
As said, there has to be a better solution. :P
Craft on KerbalX

Edited by FourGreenFields
Link got broken when due to that forum change thing
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It seems everyone is making minimalist planes now. I like them, but here's something less subtle:

[IMG]http://i.imgur.com/glnoPS5.png[/IMG]
Craft file: [URL="https://www.dropbox.com/s/47ic3gqfsbr7eaf/Dok-5%20Cormorant.craft?dl=0"]https://www.dropbox.com/s/47ic3gqfsbr7eaf/Dok-5%20Cormorant.craft?dl=0
[/URL]
The finished(ish) Cormorant. Max speed Mach 2.8, cruises at Mach 2. It can carry half a dozen munitions internally, and has ECM, cannon and IR ball built in. Not exactly a turnfighter, but it's supermaneuverable and very agile.

The leading edge flaps double as control surfaces. They're not currently configured for pitch control, but if/when I set the plane up for Dynamic Deflection I'll change it so that they switch between elevator and flap mode depending on the dynamic pressure.
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I copied the F-22 wings from my F-USAF design onto a new body built with BahamutoD's new [URL="http://forum.kerbalspaceprogram.com/threads/140460-1-0-5-BDynamics-Mk22-Cockpits-v1-0"]F-22 cockpit[/URL]. The result is a supermaneuverable fighter with a wave drag of 0.08m2. (Or 0.24m2 with bits an pieces added.)

[img]http://i.imgur.com/GOoGgZg.png[/img]

This cockpit seems to put the stock cockpits to shame in terms of aerodynamic design.
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0.08? That's mad. What are the 'bits and pieces' that raise it, weapons? (i.e. could you keep it low with bays?). Below 0.2 is doable with stock, but if that cockpit is the cause, it does seem pretty spiffy.

Downloading the mod now, because I can't resist the possibility of making a plane with a DCS-style clickable cockpit any longer. I've mostly used stock parts for my planes thus far, but I feel a heavily modded one coming on...
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[quote name='Doke']0.08? That's mad. What are the 'bits and pieces' that raise it, weapons? (i.e. could you keep it low with bays?). Below 0.2 is doable with stock, but if that cockpit is the cause, it does seem pretty spiffy.[/QUOTE]

If I'd have to guess, I'd say that that might be due to problems with FAR's calculations. Once got negative wave drag on a plane, and allthough ferram did fix it, one can never be sure that there are no similar bugs around.
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I've done the necessary updates for the Su-27, it's now very post stall manoeuvrable except that asymmetric flameouts can occur at high altitudes if you try a 180 degree direction change on the spot
[img]http://i.imgur.com/nzTIZhk.png[/img]
Specs:
Gross Weight: 20 tons
Top speed at 10,000m mach 2.4
Top speed at sea level mach 1.3
Service ceiling 22,000m
[url]http://www./download/5856fhx9j6fb1z6/FAR_BD_Su-27_Flanker.craft[/url]

Also I updated the F-16C, the new jet makes it a real contender whereas before it had a quite limited range, and was very poor at high altitude. It's also been aesthetically modified to look more like the falcon and is in fact less draggy as a result, it's about as fast as the Su-27 even with only one engine
[img]http://i.imgur.com/PMFkLwi.png[/img]
[url]http://www./download/3j45a1n8aam283i/FAR_BD_F-16C_Fighting_Falcon.craft[/url]

The F-18 is same as ever with the new engine, really the only thing I did was swap engines and it was fine
[img]http://i.imgur.com/NIhYj6z.png[/img]
[url]http://www./download/b19r3s4mqmawcs9/FAR_BD_FA-18J_Super_Hornet.craft[/url]

Mods: BD armoury, FAR, adjustable landing gear.
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I rebuilt an F22 as there's a new cockpit to play with, has a wave-drag of 0.25 with everything fitted (including targeting ball and ECM) and is just about super manoeuvrable. The infernal robotics weapons bay allows attachment to the inside of the doors to squeeze a bit more in without any bad clipping.

[img]http://i.imgur.com/AsTAsoZ.png[/img]
[img]http://i.imgur.com/0ZKa4vC.png[/img]
[img]http://i.imgur.com/6ZJNuYK.png[/img]
[img]http://i.imgur.com/USFPWwm.png[/img]
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[quote name='CrisK']Looking good, gentlemen!

Darren9, I used IR in all of my old designs, but I stopped using it simply because it doesn't seem to be actively maintained.[/QUOTE]I don't think it'll be updated until it stops working, Zodius has been in the Rework thread recently with a couple of new parts in development. I'm not sure CKAN will allow it to be installed but it seems to be working fine :)
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[quote name='Darren9']I don't think it'll be updated until it stops working, Zodius has been in the Rework thread recently with a couple of new parts in development. I'm not sure CKAN will allow it to be installed but it seems to be working fine :)[/QUOTE]
Thank you for sharing! I will have to give it another look.:D
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Not what I wanted to build, but good enough to upload anyway: The P 29 "Hobby"

Wanted to build a high-wing-loading straight-wing plane, and overestimated the wing size I needed for that. Ended up being much more tight-turning, but also slower than intendet.

Only supermanoeuvrable below Mach 0.4 or something.

Craft file here

Edited by FourGreenFields
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It's impressive how drastically different wave drag area can be between Moderate Area Ruling and Strict Area Ruling.  A plane that was below 0.3m2 became .75m2.  I'm still trying to get a handle on getting the AI to work reasonably with the panther without restricting the gimbal range significantly.

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And that's what the "Hobby" was meant to be:

(Just ignore the lack of fuel useage on the 2. screenshot, I use the infinite fuel cheat to keep the weight high, which does matter for speed with wing loading like that)

 

Allready tested G-load at low alt, and it passes the requirement. Also able to land, allthough it needs a relatively long runway for that, and isn't exactly a pleasure to fly at low speeds (ridiculous dihedral effect from V-tail, and I don't think I can counter that without messing the aerodynamics up, due to the small wings).

 

Going to upload the P 27 "Peregrine" soon™, along with more screenshots.

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