The MachingBird Challenge!

[numerobis]

I'm working on a ridiculous proof-of-concept entry, but it is *so* touchy! So far, I've gotten it up to 2341 m/s. The problem is the very small range between high enough for high speed and the top of the atmosphere. A bit more tweaking the flight profile and I should get a better top speed.

But generally I don't think we can much improve on the intake-stacking 2344 that m1xte got: my concept plane has 2,001 intakes.

[m1xte]

Lulz

Maybe you'll need 2345 intakes

[numerobis]

My math suggests I should be able to get 2370 m/s with this configuration. I suspect my math is wrong.

[GraviTykillz]

My Entry:

The Shovel

Stock ,Manned,with some clippin:rolleyes:

Take off:

Top Speed:

Same Bird. Better Speed. 2,238

Edited October 2, 2013 by GraviTykillz

[TTurchan1]

I disagree. It does very much imply that. The whole point of the challenge is "Highest Speed Over Land". If you're leaving the planet, your not doing the challenge.

IMHO...this is uber-cheaty, not in the spirit of the challenge. However, the OP does have uber-cheaty categories. I would say this attempt is no good, but try again for #1 cheat slot Just my opinion, and you know what they say about those!

Again, I was basing the speed off the "highest speed over land" part of the flight log, or the surface velocity. Besides, the Stock Unmanned Exploitational category on the leaderboards is meant for exploits, so i exploited the fact that your surface velocity is incredibly high when you are very far off the surface of the body you are orbiting. Also he says that you are not supposed to abuse sub-orbital hops to increase the velocity, which i did not do.

[TTurchan1]

How do you get from 5 km/s at the top of the atmosphere (totally legit-seeming via infiniglide) up to 421 km/s? Where's your extra thrust coming from? Changing the SOI should only get you at best from 5 km/s above Kerbin to 11 km/s above the sun, if you aim just right.

Well, for one, Kerbol (the sun) has a rotational velocity of 3.8km/s, compared to kerbin's 174m/s rotational velocity, and secondly, if you are orbiting at very high altitudes, you will have a MUCH higher surface velocity.

[p512]

While I don't have a record speed my landing was pretty spectacular. After semi-orbiting Kerbin at a max surface speed of 2271.3m/s I came to be right in front of the KSC as my fuel ran out. I took the opportunity and tried to land there.

There it is:

Trying to slow myself down to using the wings while keeping an eye on the electrical charge

Slightly overshot that

Looking good so far..

Brace for impact!

Touchdown! Was pretty soft actually.

[numerobis]

Well, for one, Kerbol (the sun) has a rotational velocity of 3.8km/s, compared to kerbin's 174m/s rotational velocity, and secondly, if you are orbiting at very high altitudes, you will have a MUCH higher surface velocity.

If you exit the Kerbin SOI prograde, your heliocentric surface velocity would thus be your velocity compared to Kerbin, plus 9.2 km/s from Kerbin's velocity around the sun, minus 3.8 km/s from the sun's sidereal rotation speed, a net 5.6 km/s. So I was generous when I gave you 6 km/s off that switch. Where did you get the other 400 km/s?

The second claim I am almost certain is false. The difference between orbit speed and surface speed depends only on your inclination and the sidereal rotation speed, not on your altitude.

Prove me wrong, but I suspect there's something weird going on in your entry.

Edited October 3, 2013 by numerobis

[Shrike42]

Wow, the field is much more spread out now. I might have a chance, especially with the improved ASAS, to get 3rd placeish.

[TTurchan1]

If you exit the Kerbin SOI prograde, your heliocentric surface velocity would thus be your velocity compared to Kerbin, plus 9.2 km/s from Kerbin's velocity around the sun, minus 3.8 km/s from the sun's sidereal rotation speed, a net 5.6 km/s. So I was generous when I gave you 6 km/s off that switch. Where did you get the other 400 km/s?

The second claim I am almost certain is false. The difference between orbit speed and surface speed depends only on your inclination and the sidereal rotation speed, not on your altitude.

Prove me wrong, but I suspect there's something weird going on in your entry.

Yeah, I know that second claim was false, i don't know what the **** I was smoking when i wrote that (I wasn't smoking anything, i was just tired), but i dont know what the hell is going on with my entry. All i know is that your surface velocity is ridiculously high whenever you are orbiting the sun.

[Guest links123]

Second claim is not false it is very much true.

[peadar1987]

Okay, so it's not a record, but I'm pretty proud of it:

Huginn V (no mechjeb, no dev console, all stock parts, some minor intake spamming!):

Franklin Kerman looking distinctly unhappy throughout!

[Nao]

Welp did anybody notice anything strange with flameout logic in newest patch?

Managed 2200+ m/s at around 33km altitude with only two Ram intakes and a 4,5 ton craft (200+ litres of fuel on board with Mk1 cockpit) with one Turbojet with working at 1/3 throttle. It's either normal and I'm terribly out of the loop or on to something with this.

[Shrike42]

Welp did anybody notice anything strange with flameout logic in newest patch?

Managed 2200+ m/s at around 33km altitude with only two Ram intakes and a 4,5 ton craft (200+ litres of fuel on board with Mk1 cockpit) with one Turbojet with working at 1/3 throttle. It's either normal and I'm terribly out of the loop or on to something with this.

I was doing that, too. It felt a bit odd compared to the old machingbird attempts, like I was getting more leeway in keeping my engines running. I had been thinking it was just since I hadn't played much KSP and definitely not done much high-altitude flight for many months...

Also, with the reaction wheels, a high-altitude flameout is much less of a charlie foxtrot. Just flameout one engine, reduce throttle, and the ASAS corrects the heading smoothly.

But in any case, my first design is too heavy by far. Can't break 2260. Gonna rethink it, try to avoid my old biplane designs now that stability is much more easily achievable.

[shael6636]

So my 1st challenge entry MCB Mk-1 (Manned, Stock, Mechjeb)

Take off:

In Flight:

Safely Landed:

[Shrike42]

Breaking 2280 with 4.00 Intake air and a ceiling of 38k. Even threw on some generators so that my reaction wheels wouldn't run out of power. Gotta beat at least 2300!

After reviewing the super-high-end manned craft, I think I'll be happy with 'very fast craft that still looks like an airplane'.

I'm quite pleased with the design as well, it's extraordinarily stable and glides nicely at all fuel levels.

2300 m/s reached...!

Um, how do I get a mission log?

Edited October 6, 2013 by Shrike42

[TheHengeProphet]

Holy Bejeebus peeps! Several new entries! I've been rather busy, but I'll try to get the OP updated before this weekend is out.

Um, how do I get a mission log?

It's been a while since I've played, to be honest (being a busy adult with many "important" things to do), so I don't rightly remember, but if I remember correctly... F3?

{edited to correctify my mistake}

[Edit to avoid doublepost]

Alright, folks, list has been updated.

TTurchan1, I have accepted your entry. That thing is still horrifying. According to your maximum speed, you achieved 12.8 km/s, which is impressive. That would have certainly allowed you to kick out into solar orbit. I would have really liked an in-atmosphere reading, or at least one before you left SoI, but whatever.

GraviTyKillz, what do you mean by "clipping"? Did you use the dev console to allow your intakes to stack like that, or did you fanagle them into position?

p512, I'd love to see a full run of that! If you ever get around to it, throw it up and I'll add it to the leaderboard.

peadar1987, nice run! I'm still not sure how you guys stack those intakes like that, but kudos!

shael6636, I'm impressed you got that fast with radial intakes... those things are horrid for high speed. Truely, good job!

Edited October 7, 2013 by TheHengeProphet

[shael6636]

shael6636, I'm impressed you got that fast with radial intakes... those things are horrid for high speed. Truely, good job!

Thanks took about 1 1/2 days to get the design right with testing and redesigns. Will be submitting another attempt using Far without using mechjeb just to make it fun in the next week or so.

[peadar1987]

@TheHengeProphet

Stacking intakes is a bit of an exploit, if you put the smallest cubic strut facing forwards on the front of your wing, fuel tank, or engine body, then you can attach ram intakes to both the front and back of it, so if you stack a couple of cubic struts, then you can get five or six intakes (Or as many as you want, but I'm using the very fuzzy rule of "it still has to look a little like it would actually fly!) onto one engine body without disabling clipping. Then I used the highly scientific method of copying and pasting the engine body with intakes attached wherever the editor would let me!

I think once they overhaul the spaceplane parts and fix aerodynamics and clipping it will completely change this challenge

[Hodo]

Not sure if considered Stock manned, but used stock parts, didn't even use my Kerbal Engineering. Just FAR.

I present the Viper MkIII

Maxed out at 1721m/s

And I didn't use more than 3 intakes per engine. There are 13 intakes on the craft, 12 RAM intakes, and 1 engine nacelle.

I know I can do better using B9 parts would that be a modded entry? Or is B9 not allowed?

Edited October 8, 2013 by Hodo

[numerobis]

This is not an official entry, but I wanted to see how much damage I could do to reality using KSP jet physics. Why it's not an official entry:

1. Vertical liftoff. I wanted to avoid having aero surfaces, to prove this is all jets.

2. Part cfg editing. I edited the intakes to have 1000x the stats. The advantage is fewer parts; the disadvantage is more drag -- dramatically more at low altitude.

3. Using ModuleSMRTGimbal to allow me to have a tractor configuration.

The result: 2525 m/s using just turbojets, basic jets, and parts amounting to 4k air intakes. Yes, that is above the 2400 m/s maximum where turbojets don't push anymore: there's a trick.

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[tavert]

Nicely done, way to probe new boundaries of intake abuse. Intakes as canned-air oxidizer tanks for jet power in vacuum, go figure.

[numerobis]

I didn't invent the trick; I picked it up from Nao who mentioned someone else using it.

Intakes as tanks are fantastically inefficient: 10:1 dry mass ratio, rather than the 1:8 ratio for bipropellent tanks.

I suppose I should have modded the radials since they have 2:1 dry mass ratio instead.

[allmhuran]

I tried to use this "stored air" technique to get something into orbit on jets alone, but yeah... without editing the parts the number of intakes required is well beyond absurd.

[numerobis]

I've done it with just a modest number of intakes (maybe 6? 10?) but all that clicking is a pain; one wrong click and disaster strikes.