What is your fastest low altidue aircraft?

[katateochi]

More details on what i said earlier:

I just went and made a successful Mach 1 at sea level capable Jet powered plane. (340.3m/s or greater at under 100m max altitude)

http://i.imgur.com/nfvS5vl.jpg

Stats:

• Total counted weight full fuel; 11.495t
  
• Total counted weight empty fuel; 11.095t
  
• Engine weight; 10.8t
  
• Launch engine weight fraction; .9395
  
• Final engine weight fraction; .9734
  
• Engine burn duration; 31 seconds @ max throttle
  
• Minimum take off velocity; 180m/s
  
• Velocity at end of runway; 295m/s
  
• Time to reach end of runway; 11 seconds
  
• Maximum velocity (under 100m altitude) 341m/s
  

Single stage, bare minimum parts except engines. All excess weight was trimmed, even including minimizing the number of wing surfaces and choosing the most weight efficient ones. Even different combinations of air intakes were played with to minimize intake drag. The number of engines was a fine tuning process also. 8 Turbojets doesn't provide quite enough thrust to reach Mach 1, and 10 run out of fuel before accelerating enough to reach it. (Also .5 intakes per engine + 1 is the most efficient ratio in terms of most thrust per intake drag) We're basically tuned to a razor fine point here. Fly it below about 85 meters and there's too much drag to reach Mach 1 before you're out of fuel. Fly it above 100 and it fails my "at sea level' requirement. And at Mach 1 you're above 97.3% of the planes total weight being dedicated to engines. (The only way to get faster is to raise this % and it's virtually impossible to do so any further)

Just tuning it to go from 339m/s to 341m/s top speed took several hours and a fairly major re-design. If anyone else is able to hit even 343m/s without ever breaking 100m max altitude via single-stage jet only I'd be crazy impressed.

hadn't seen this before I posted my latest.

that's pretty cool, certainly proves its possible to hit mach1 at sea level and defines the boundaries nicely. Nice bit of engineering. My criticism of it would be that its kinda more of a one way missile than a plane as you only have 31 seconds of fuel. I guess coming back in for a landing is out of the question! It does look cool thou with the mach effects!

[Van Disaster]

I think the "motion blur" is just the low-altitude high speed effect and I just picked a good moment for the screencap. Ferram's mod does make major changes to aerodynamics ( and nerfs jet engines slightly ), it won't affect anything in space or structurally.

[ROFLCopter64bit]

Sticking mainsails on spaceplanes is always fun.

[Yargnit]

hadn't seen this before I posted my latest.

that's pretty cool, certainly proves its possible to hit mach1 at sea level and defines the boundaries nicely. Nice bit of engineering. My criticism of it would be that its kinda more of a one way missile than a plane as you only have 31 seconds of fuel. I guess coming back in for a landing is out of the question! It does look cool thou with the mach effects!

Yes, squeezing out that last bit of speed to hit Mach 1 requires defining "plane" in a fairly loose sense of the word. Making a plane that can do Mach .9 is fairly easy, and in fact this little thing here will break Mach .9 on a single engine and can fly to the island runway + land there before it runs out of fuel.

http://i.imgur.com/66uvIpL.jpg

While it is most certainly still optimized for speed runs, it certainly fits wholly in the plane category with the ability to take off, fly to another runway, and land again. Unlike the Mach 1 plane which claims plane status on more of a technicality.

It just so happens that the was everything balances out in KSP, crossing that line between Mach .9 and 1 is the barrier where the efficiency requirements increase exponentially. (And really .95 isn't terribly hard either) You can make a Mach .9 capable plane with a variety of designs and it will still function. Mach 1 of the other hand has to have nearly everything tweaked to absolute minimalism or it just won't happen. Hell, that plane in nearly unturnable because it has so few wing surfaces to minimize weight.

[katateochi]

ah yes, that's much more of a plane. I think I prefer it being more like a plane and not quite hitting absolute mach1, mach .9 is good enough! Nicely done bit of research, that's interesting there is such a jump up in design requirements from 0.9 to 1.

[xclusiv8]

So I replaced the 3 basic jet engines on my Screaming Gnat plane with 3 turbo jet engines, result; catastrophically uncontrollable, top speed not determined.

I replaced the two side engines with turbo jets, leaving one basic in the middle. handled like an epileptic bee, top speed was no greater than before.

replaced just the central engine with a turbo jet, leaving two basics on either side; this I could fly, but it was still much less dexterous in its manoeuvrability and top speed was only increased by a few m/s.

So in the end I've gone back to the 3 basic engines because that seems to be a nice balance between fast and very very manoeuvrable.

nice! are you using the FAR mod?

I must give this FAR mod a go. I heard that is make some major changes to the game so I've been a little unsure if I wanted to use it. Is that motion blur being added by it?

I sure am. Love the FAR mod. Makes planes behave more like planes and less like flying bricks It needs more attention to detail when building the planes though.

[Cesrate]

Just have a look at the Supersonic Diamond in FAR, 1,000m/s isn't problem.

[Stealth2668]

This is my plane which I named Phoenix X-1 because of the re-entry effects it gets when it goes fast. Low altitude max speed is a little over 250 m/s and the fastest speed was almost 1700 m/s at around 20km

Edited April 26, 2013 by Stealth2668

[Tanya Sapien]

for some reason parts start to fall of once I hit above 300m/s.

Okay, Jeb

[flyin_ruski]

There really ought to be a topic in challenges for this. So if this is for low altitude speeds I present to you....this. I havnt named it yet.

then I tried turning off ASAS and pulling up.

Edited April 29, 2013 by flyin_ruski

[JNC]

[Omicron314]

I have a glider craft that can easily do 600 m/s at sea level. I use a rocket-on-wheels to launch it (which only gets it up to 250 m/s), but for some reason it keeps on accelerating until nearly Mach 2. I have the FAR mod installed, by the way.

I have pictures, but they're on my computer, which I do not have at the moment. I'll try to post pictures eventually!

[Sir Nahme]

does it have to be one you've successfully landed?

if so... 60.5 m/s and it was a blimp

[nhnifong]

What is a plane anyways

[MR4Y]

My first White Knight carrier plane version would break the sound barrier even before taking off.

But here's Nimrodel Mk III:

Edited June 30, 2013 by MR4Y

[katateochi]

What is a plane anyways

*snip

That is as great as it is small!

How fast was that going? Also, can you fit a command chair onto that?