Ion Plane Research Challenge

[Deddly]

3 hours ago, TheGuyNamedAlan said:

gosh is this even possible??

Well if it is possible, we are going to try our hardest to find out.

[Jetski]

6 hours ago, Deddly said:

@ArchgeekThat's very impresive! it is still Juno powered at the moment, right? If can get the same performance from Ions, you become the first person to design an Ion plane that can actually leave the runway, however briefly!

@JetskiWhoah - do the ion engines not interfere with each other's thrust when stacked in line like that?

yes, the thrust works fine to pass through, at least in 1.05. I don't think it has been changed. Unfortunately, 5 ions stacked gives 0.01 TWR in atmosphere

[Draconiator]

14 hours ago, Archgeek said:

And here are the results of thinking smaller:

This thing can just about hop into the air at ~13m/s, but only briefly.

It needs about 18 m/s to sustain take-off.  Still not as slow as I'd like.

Hmmmmm....thanks for the research Arche!  I love this thread, it's like we're working together for a common goal

[Deddly]

6 hours ago, Jetski said:

yes, the thrust works fine to pass through, at least in 1.05. I don't think it has been changed. Unfortunately, 5 ions stacked gives 0.01 TWR in atmosphere

So you just place an engine directly onto the rear node of the other engine? That would reduce drag. Every little bit helps

Edited May 2, 2016 by Deddly

[The_Rocketeer]

I found a little extra time for this today (yay for bank holidays!). I managed to get up an unassisted rolling speed of about 13 m/s before tipping off the end of the runway in a solar-only powered craft. The bad news: it required 24 (not 48! - Ed) Dawn engines, in one stack, to achieve this.

If anybody else is trying this, I recommend raking the wings' angle of attack to provide a drag shadow for the solar panels. I say this because I noticed that the panels on my rear wings produced far less drag than those up front, which I guess was caused by the shadow of the wing in front. I'm not certain about this in KSP's aeromodel, but I suspect that wing drag is less detrimental than other kinds of drag because some of it is converted to lift, which is a force we want after all.



^^ This was bad advice, don't try it. It hurts acceleration far more than you gain.

I think this was the craft, but I managed to overwrite it with a worse design revision. Still, those markings on the runway give an indication of the acceleration I'm getting here. As you can see, the screenshot was actually accidental - I was just trying to turn on the overlay.

Edited May 2, 2016 by The_Rocketeer

[Deddly]

@The_Rocketeer that makes yours the fastest ion ground vehicle that we know of. That's not insignificant

Edited May 2, 2016 by Deddly

[Knaapie]

Imo allow the e50 electric propeller from KAX to give them a fighting chance

[Deddly]

15 minutes ago, Knaapie said:

Imo allow the e50 electric propeller from KAX to give them a fighting chance

Well, of course you can go ahead and do that, and it'll make an interesting project, for sure. But it's beyond the scope of this challenge, which is stock only.

[The_Rocketeer]

21 minutes ago, Deddly said:

@The_Rocketeer that makes yours the fastest ion ground vehicle that we know of. That's not insignificant

Would you be willing to post a screenshot of your craft?

Check my earlier post, I've edited out a mistake and added a pic.

[Deddly]

@The_Rocketeer That's fantastic. I think we're actually getting somewhere here. Don't the 1x6 panels have less drag, though?

[The_Rocketeer]

@Deddly could be. I don't take the most scientific approach to all this and like I said earlier, I've been away from KSP a long time - in the old days the static panels were best because they were massless, but since u mention it, until I was made aware of that I depended heavily on the 1x6 panels. The major downside I recall is their fragility.

[Deddly]

For the record, I don't actually know that as a fact. I haven't seen any figures for drag. If anyone knows of a chart we can look, please point it out for us.

[wibou7]

This thread is incredibly interesting.

What about using rover wheel to roll past take off speed THEN jettison said wheel?
@The_Rocketeer wouldn't that work to get you past 24m/s?

But then I guess you wouldn't stay airborne for very long..?

[Deddly]

3 minutes ago, wibou7 said:

What about using rover wheel to roll past take off speed THEN jettison said wheel?

That would definitely work for the Up, Up and Away category.

[Ultimate Steve]

It may not qualify for this challenge, but I just got an ion plane to fly. Pics coming soon. I had to use rover wheels for a buildup, and I had to launch off of Kerbin's tallest mountain (where the thrust is better). It also cannot sustain thrust for long, because of the current battery capacity.

 

EDIT: I have now created a new model that can fly 5 kilometers and can gain altitude and speed in flight. Its maximum speed has been clocked at 70.4 meters per second.

Edited May 2, 2016 by Ultimate Steve
Update

[The_Rocketeer]

1 hour ago, wibou7 said:

What about using rover wheel to roll past take off speed THEN jettison said wheel?

 

@wibou7 Yes that would work, but you could do the same for a glider craft without any other propulsion at all and obtain limited flight. For me, this exercise is more interesting to solve without workarounds, i.e. using ONLY ion propulsion, and ONLY solar arrays for power, is it possible to achieve flight. That might be a bit hardcore for some, and there's plenty of other goals in the grey area between that and the stated challenge, but for me that's the Blue Ribband, the ultimate accomplishment.

[Moesly_Armlis]

On 4/29/2016 at 3:44 PM, Deddly said:

UP, UP AND AWAY: Can you invent an innovative launch method to get an ion plane in the air and beyond?  (Rover wheels to build up speed on the ground, take off from a mountain, electric propellors etc., but not a rocket booster stage)

I am pondering a trebuchet launch method to attain altitude and velocity.

 

 

Edited May 3, 2016 by MoeslyArmlis

[Jetski]

2 hours ago, Ultimate Steve said:

It may not qualify for this challenge, but I just got an ion plane to fly. Pics coming soon. I had to use rover wheels for a buildup, and I had to launch off of Kerbin's tallest mountain (where the thrust is better). It also cannot sustain thrust for long, because of the current battery capacity.

 

EDIT: I have now created a new model that can fly 5 kilometers and can gain altitude and speed in flight. Its maximum speed has been clocked at 70.4 meters per second.

Pics!

[Moesly_Armlis]

Trebuchet style launch

The craft for now is a

and two swept wings

with a guidance uinit

 

9.72 tonnes with 30m/s velocity

The pivot point is not strong enough and is failing.

The decoupler used was set to zero ejection force.

Decoupler ejection force is not banned for this challenge and maybe it should,  Seems cheaty to stack hundreds of these decouplers to propel the vessel.

Edited May 3, 2016 by MoeslyArmlis

[Ultimate Steve]

Well, @Jetski, I'll do you one better. How about a video?

 

 

 

[wibou7]

Ok, I've made several attempt tonight and I wanted to share my progress.

First, this is the "Mutant Butterfly"

It was promising, I could get up to 14m/s but I could take off so slowly.

 

Then I experimented adding tons of winglet. Meet the "Hornet"

Needless to say, it did not end well:

 

 

My most promising attempt so far is the "Winter Goose":

It can accelerate up to 21m/s on the runway... Needless to say, it is not enough to take off.

 

However, if I somehow bring it to a higher altitude IT IS capable of level flight. At about 4250m, the ION engine has enough trust that it is capable of level flight at ~50m/s. It even build up (very VERY slowly) speed given enough time.

I used solid fueld booster on a cart (I know it is against the rules, I was testing out the concept) to bring it to an altitude of 4500m on those pictures. That's why you don't see any wheel on that one (it got jettison with the booster). Then KSP crashed on me; I take it as a sign it was enough for tonight.

5 minutes ago, Ultimate Steve said:

Well, @Jetski, I'll do you one better. How about a video?

<video>

 

Impressive!!

Have you tried replacing the fuel cell array with static solar panel? I'm pretty sure you wouldn't need that many ion engines if it wouldn't be for the additional weight of the fuel.

Even accounting for the drag, it should be superior to using fuel cell at this altitude.

[EpicSpaceTroll139]

I've noticed that the new large static solar panels can sort of work as wings. They're not fantastic by any means, but this perhaps could allow slightly lighter structure. Ex: one could mount them as wingtip extensions. I might try my hand at this tomorrow.

[Moesly_Armlis]

Trebuchet is an unruly monster. 

When this attempt with an ion glider made 91m/s with a 2.5 tonne craft I was excited and hopeful.

Nearly made it to the end of the runway.

Now for the past hour my attempts are pathetic.  Not sure what changes (only change I made was reducing mass on the glider) I made to make this worse because now the trebuchet is tearing itself apart and explodes.  Cannot even launch the glider.  What is weird is the trebuchet kinda works on the first launch and any revert to launch is then ending in failure.

[Deddly]

@wibou7 and @Ultimate Steve have just made history, and I've added links to their posts on the first page! Wonderful stuff.

@MoeslyArmlis - I love the idea of the catapult, and I look forward to further progress reports with bated breath

Edited May 3, 2016 by Deddly

[wibou7]

2 hours ago, Deddly said:

@wibou7 and @Ultimate Steve have just made history, and I've added links to their posts on the first page! Wonderful stuff.

@MoeslyArmlis - I love the idea of the catapult, and I look forward to further progress reports with bated breath

Hehe thanks for the enthousiam but I don't consider this version to be final at all.

My design (just like @UltimateSteve design) has a limited autonomy. I am confident I can improve it into something a least a little bit usable.