Solar Electric Airplane Speed Challenge

[g00bd0g]

This challenge is for the aero geeks This challenge requires the Firespitter mod, FAR is recommended. You can use any of the common mods including FAR, procedural wings and fairings, etc...

The Challenge

Make the fastest pure Solar Electric Airplane you can!

The Craft

Must use electric motors from the Firespitter mod

Must use Solar Panels for energy

No energy storage beyond what is built into command pods

No liquid fuels allowed, No RCS, No Jets, No rockets, No Ion drive, etc...

No user "modified" parts

No dev console or ridiculous parts clipping

The Flight

Takeoff

Accelerate to max speed (at any altitude)

Must hold sustained speed in level flight (must make a a best effort for pure level flight (+/- 10m/s vertical speed for 10 seconds) (must "average" to level flight)

Must show electric resource to validate no use of battery energy during speed-run.

Land in one piece on an airstrip

Judging

I'll maintain "stock" and FAR leaderboards

And possibly Manned and Un-Manned (Un-Kerbaled?)

Must provide sufficient photo/video proof (Video Preferred)

Craft files must be available for verification of performance upon request

I will maintain a leaderboard of entries "Max Speeds" for each category, whoever is at the top is the current champion. Unlimited parts counts, tonnage, altitude, etc... I want to see what people will come up with. We'll refine the rules to "keep in the spirit" of the challenge if we need to.

LEADERBOARD *Updated Jan 23rd, 2014

Stock Board

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No Entries Yet

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FAR Board

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Darren9's Unnamed2 : 262 m/s @ 8000m(kerbin atmosphere as others unless stated) - Features 'hang tight' external control, low cost, forward swept

localsol's SolarScreech : 248.9999 m/s - Features semi-replica, reactionwheel-free slightly unstable flight

Darren9's Unnamed : 239 m/s @~6185m - Features recessed fuselage, two engine

G00bd0g 's Solar Speeder : 238 m/s - Features very high aspect ratio, stable

localsol's Cynoid Stork : 224 m/s - Features birdlike wing, moar yaw control

m1sz's electric speedor 2 (yep. crappy name ): 215 m/s - Lots of solar panels

My Entry

Name: Solar Speeder

Max Speed: 238m/s

Mods: FAR v0.12.4, Firespitter v6.1.1

Craft File: https://drive.google.com/file/d/0B4zLBUio4kInY0JLcEJnVG5MMzQ/edit?usp=sharing

Edited January 24, 2014 by g00bd0g

[brobel]

This looks cool might have to give it a try

[g00bd0g]

This looks cool might have to give it a try

Please do, I'd love to see what other people come up with...

[localSol]

Edited out about 5 minutes of loading, time compression and the more monotonous altitude gaining flight parts. Kept the needed and fun stuff. Based on a bird I saw today. Landing gear setup for easy landing, but takes off at 70 m/s as a result. Possibly setting up flaps would help for another version. It lands really gently, that's a nice break from flying supersonic planes. I was not certain about the level flight rules when I made the video today but this plane is definitely capable of stable flight for more than 10 seconds and I got about 185 m/s at typical altitudes at around kerbal-noon. I went into a dive and got up to 224 m/s highest speed over land (both in video). I made this plane with general purpose in mind too for fun. Too bad the propeller animation wasn't working for some reason, it's one of my favorite animations. Engine was functioning normally as far as I could tell though with Firespitter 6.1.1 and FAR 0.12.5.2.

http://youtu.be/YidliNC3x8Q

Craft file:

https://dl.dropboxusercontent.com/u/6231140/KSPstuff/Cynoid%20Stork%20v6.craft

Requires B9 4.0c+, PWing 0.7+, StretchySRB v8.1+(for empty fuselage of any length), Taverio's Parts Pack 1.51+, Firespitter 6.1.1+.

Let me know if this craft has a working prop animation if anybody tests it? In that case I had better recheck mod installs.

G00bd0g's plane, that's good. I have never seen a wing that thin also with what I think are the new curved tips in pwings. Minimal parts too. And it's getting good resource efficiency by using few small control surfaces. Doing this challenge made me want to maybe mod a service module from the Alchemy parts pack, to take out the reaction wheel and other stuff , to use it as an inline solar fuselage, which it basically already is plus the other convenient stuff for spacecraft. It would save lots of 'part count', also I wonder if a premade part like that with working solar panels on only one side (for skyward) is possible, but still using only one part.

Edited January 15, 2014 by localSol
spelling misspellings

[Darren9]

I just installed FAR and, incredibly, my design got into the air, and made 239m/s in true level flight Has enough solar to go full throttle with 2 engines at 5000m, uses Firespitter, FAR, Skeppies mini-pack, procedural fairings/wings and an ID Strong strut.

Edited January 16, 2014 by Darren9

[localSol]

I remember your amazing nuclear powered land vehicle with suspensatron suspension.

Another good plane. I like the all-pwings tail. Are those panels inside a recessed fuselage? Cool. I'm glad you mentioned 5km for a good altitude, I used that to start on another plane.

[720p in Kerbalvision where available]

http://www.youtube.com/watch?v=EjjemvKuXr0

I made this 'K-84 SolarScreech' based on the F-84H Thunderstreak aka Thunderscreech which was capable of 299.517 m/s, with a gas turbine propeller and "emitted ~15 sonic booms per second, even at low speed". They say it was loud(!), I've never actually heard a recording.

This solarscreech is just barely fast enough to start mach effects and get the atmospheric sound mod activating, which was really fun listening to. Very twitchy plane and hard to take off especially without the command pod's standard reaction wheel enabled, and I didn't even try landing!

For level flight speed I was able to maintain 250 m/s at about 5580 meters for 5 seconds and 248.7 for 10 seconds at about 6100 meters, both in video.

Craft file : https://www.dropbox.com/s/adddcnjsrzp4d9r/Solarscreech4.craft

Edited January 17, 2014 by localSol
typos

[Darren9]

Thanks, my first go with FAR and I thought I may be able to fool it with the solar panels 3/4 enclosed in fairings that shield drag (there's a line of small girders under the solar panels). It didn't work though and twice the power still only gets the same top speed. I'm going to have to follow you and go with less parts, mass and a small engine, maybe some sort of ultra-light flying command seat could beat 250m/s. As you said though takeoff/landing without SAS/reaction wheels is risky

[Darren9]

I got up to 262m/s at 8000m with a twin engine flying command seat. It takes off and occasionally lands successfully on three of the bi-plane tail skids

[ihtoit]

I had a solar-ion to orbital altitude, but that only did 35m/s at takeoff and not much faster at altitude...

[localSol]

Nice forward swept one. Funny that, I guess a poor transonic kerbal would really be obliterated. I have DRE, I wonder if it would do that. How can you get so much power with what looks like only 15 panels? The pointing straight up must help, though I had to use 30+ for one folding electric engine. With one engine I had takeoff TWR of about 2.0(!), I wonder what 2 or 3 engines would do? I noticed some weird drag effects sometimes with procedural fairings on reentry where the drag was down to practically 0.000. Can't be right? Otherwise I used a huge one as a very good lifting body on a rocket with no unusual effects AFAIK yesterday. I'd like to get something to takeoff at 35 m/s! To the drawing board.

Qualifying for land-ability : Adjusted landing gear position relative to center of mass for more neutral gear position , adjusted control surface purpose and travel, added flaps and spoiler function with FAR for better takeoff and braking while landing. On this particular attempt, I flew down too steep while landing and scraped the wing a little - it is easier to land than that usually. Tail elevators maybe could use toning down slightly.

http://www.youtube.com/watch?v=ZftZE93OTCc

Craft file : https://www.dropbox.com/s/5v7ypiau7lueoey/Solarscreech5.craft

[Darren9]

I'm getting some "interesting" effects with powering the props, if you haven't noticed then I may have somehow broken something (all I've done is install mods). For me, at ground level with those panels and props I can do maybe 1/6th throttle, as I climb I can increase throttle, only above 8000m can I go full throttle. I suspected it was a side effect of how Firespitter reduces thrust for props at altitude, and lowering the thrust also lowers the charge needed for full throttle (electricity proportional to thrust not throttle setting). Does yours not work like that? I hope I don't have to re-install and add another 30 panels - that'll slow me down a bit. And yes, it only works flying flat at mid-day

Edited January 17, 2014 by Darren9

[fluffysnowcap]

any chance of getting a leader bord

[localSol]

Thank you, yes, I didn't notice that but I get the same thing and it makes sense to me. I could improve resource and part efficiency by using less panels. More panels in more places let you maneuver better though of course a plane with no batteries is unusual to do that. At 8000m my plane's electric folding prop made 5.2kn at full throttle using 4.95 energy units per second reported by Fusebox. It uses 20.02 energy units at 1000m at full throttle. There, even at level flight it seems to reduce power over the first 5 seconds that I can maintain full throttle, from 23kn to about 21kn. I wonder what that is simulating about the engine if anything.

The drag on the propeller reported by the right click menu seems much lower than my first conic part, I wonder why that is too. I don't know.

The 7.5 monopropellant in the mk2 pod weighs nearly 1/10th of a ton so I got rid of it. I don't remember if that's stock or part of modular fuel tanks but the flexibility of that mod and/or real fuels is really great.

Edit : Until g00bd0g comes back the unofficial unserious scoreboard of unordered maximum forum props and props :

[g00bd0g came back]

Edited January 18, 2014 by localSol

[g00bd0g]

Edit : Until g00bd0g comes back the unofficial unserious scoreboard of unordered maximum forum props and props :

Jan 17th, 2014

Stock Board

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No Entries Yet

______________

FAR Board

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G00bd0g 's Solar Speeder : 238 m/s - Features very high aspect ratio, stable

localsol's Cynoid Stork : 224 m/s - Features birdlike wing, moar yaw control

Darren9's Unnamed : 239 m/s @~6185m - Features recessed fuselage, two engine

Darren9's Unnamed2 : 262 m/s @ 8000m(kerbin atmosphere as others unless stated) - Features 'hang tight' external control, low cost, forward swept

localsol's SolarScreech : 248.9999 m/s - Features semi-replica, reactionwheel-free slightly unstable flight

_________________

Sorry for the hiatus, changing my subscription notifications now Thanks for putting the leaderboard together. Copy/Pasting now...

What amazing aircraft you guys have built! I thought my plane was near the the theoretical max, but apparently not ;p Any of you going to enter in the battery powered speed challenge?

What do you guys think about listing multiple entries per entrant? I am tempted to only allow 1 entry per person to keep things cleaner. Obviously newer/better entries would supersede previous ones.

Edited January 18, 2014 by g00bd0g

[localSol]

You're welcome and thanks! I didn't see the battery powered challenge, I'll check it out now. I built several more planes today but they didn't work the way I expected. Fun though.

I like challenges that give participants the opportunity to show what they've done in many ways instead of or in addition to a point system, since to me challenges are best with flexibility, discussion and experimentation. The badges people come up with can be pretty hilarious. I would track multiple entrants but I can see how it can be inconvenient.

[m1sz]

man!, i must give this a try, i love plane design!

(got my own challenge of fastest atmospheric plane under 1.000m)

need to install firesplitter, then ill submit my plane!

[m1sz]

ok i tryed, it's very hard!

I came with this idea, but it's useless compared with yours!, propellers dont do anything at high altitude and at low altitue it just doesnt run even close to the records

This is a hard challenge!, ill try later again!

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[ihtoit]

... I'd like to get something to takeoff at 35 m/s! To the drawing board.

...

Try something akin to this: 5 ion engines, shy of 4 tons on the gear, a few small batteries and a skin of solar tiles:

Oh, and Firespitter rear wheels to keep the weight down as well. The second you start using stock wheels your takeoff speed goes WAY UP.

[localSol]

ok i tryed, it's very hard!

Sometimes I was surprised at what happened. In your pictures your plane is climbing, how is it in level flight? I would think near or over 200 m/s at least. Even that is hard. I made many planes that were under 200 m/s but had other useful characteristics. What are the dark things used on the back? I was looking for an alternative to the stock bicoupler that causes lots of drag in FAR.

[m1sz]

i think one of the iterations of this design was arround 215 m/s, at arround 3000m, but is long gone!

the things on the back are struts covered with solar panels, nothing fancy, and probably, FAR hates it

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[m1sz]

ok, here's my entry... best i could do at the time, ill give it a try another day!

about 215m/s

name: electric speedor 2 (yep. crappy name )

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[Kingtj44]

Goodbug I am annoyed that you posted almost the same challenge twice...why?

[localSol]

ok, here's my entry... best i could do at the time, ill give it a try another day!

about 215m/s

Nice one! I like to see what people come up with, I have never made one quite like that. There are so many possible combinations.

[g00bd0g]

Goodbug I am annoyed that you posted almost the same challenge twice...why?

They are not the same challenge. They are fundamentally different. How about you actually try them before *****in?

[Fengist]

They are not the same challenge. They are fundamentally different. How about you actually try them before *****in?

Holy sh** dood. Can you take even one freaking IOTA of criticism before flinging insults at people????