Anyone made an ion plane recently?

[AeroGav]

When the game was still in Beta I see that folks managed to create electric powered ion planes.

I missed out on all that, but wanted to see if it was still possible to do something remotely similar.

I used tweakscale to boost the size of the Ox-Stat panel as much as possible , and covered my wings in them...

(also note the thrusters have been boosted to 1.25m diameter, and the larger Advanced Canard)

I knew that the Ion thruster wouldn't produce much thrust in the lower atmosphere, so i stuck a jet engine on the back with the idea to jettison high up, and fly to orbit and beyond on ion power.

 

Unfortunately,  it looks like these panels made my wing really draggy.  Even after firing up my stack of Dawn thrusters (an extra 60kn), we're not able to pass the sound barrier at 12km.     I suppose I could have tried flying even higher, but it doesn't bode well.  Also, we've used most of our jet fuel.  I guess if the sound barrier is our target, i should have swapped the Rapier for a Panther or two, which are more efficient.

Worse, it appears midday sun at the KSC only makes enough electricity for about 12kn.   That won't cut it.   Fuel cells perhaps, to boost us to orbit?

It looks like the only way to do this is to mod parts.   Wing with flexible conformal solar cells that add no drag and not much weight.   High power high temperature 1.25m  fuel cell that can run off atmospheric air and hydrogen/LF.

[Slam_Jones]

Not recently.  It was pretty easy back in .90 or .25 (can't remember which), but since the new aero stuff, it's (nearly?) impossible.

(The one Ion-powered glider I did make, back in .90 or .25)

Edited April 16, 2016 by Slam_Jones

[Archgeek]

Yup, now that Isp works correctly, they get next to no thrust down in the atmosphere.  'Not sure they ever had the TWR to make orbit on their own, though.  'Best I ever did was quite the trans-continental.

[AeroGav]

42 minutes ago, Archgeek said:

Yup, now that Isp works correctly, they get next to no thrust down in the atmosphere.  'Not sure they ever had the TWR to make orbit on their own, though.  'Best I ever did was quite the trans-continental.

Above 10km they produce near vacuum thrust like any other vacuum engine.    A mark 1 spaceplane with a large wing and no drag can accelerate to orbit on just the 60kn from an LV-N   NERV, providing something else lifts it to 10km in the first place.    Up scaled to 1.25m, the ION engines make 11kn each and can be stacked.     So , it would be possible, if you can avoid the drag problem and get enough electricity going.  Again that means modded parts though.

[KerikBalm]

I seem to recall that pre 1.0, they lacked sufficient TWR to get to orbit, and the only ones taht made it to orbit exploited control surfaces ... they were basically infinigliders with an ion drive for space.

I don't think it can be done, even allowing for something else to carry them to higher altitudes.

The LV-N has 2.5x the vacuum TWR, and doesn't need that other stuff like batteries and generators (though it will need to carry more fuel mass, its worth noting the tank mass ratio is much better)

[Deddly]

@Tsevion did it without exploiting the infiniglide bug. Again, that was in the old isp and aero settings. The thread was a fantastic read, though.

 

[KerikBalm]

Not jsut old Isp, and aero... but the old "massless parts"

"What battery weight? The radial mount batteries are massless parts right now... if I get it working I may try to do a battery-less run. But currently, other than the point bonus, batteries just make it easier... and I'm very lazy.

Honestly, if the solar panels weren't also massless, this whole endeavor would be impossible. But as it stands the entire power system is essentially free. We'll see if that changes in 0.9."

Emphasis added by me.

Those craft used *a lot* of massless and dragless parts that are neither massless nor dragless anymore.

[Deddly]

 

3 hours ago, KerikBalm said:

Not jsut old Isp, and aero... but the old "massless parts"

That's true, but @The_Rocketeer had a nice design in that thread without using massless parts. He managed quite well, but he didn't get to orbit.

[KerikBalm]

I don't see his design (the pics for the shrike III aren't there anymore)... but as far as I can tell, it just lacks batteries.

His "Shrike 2" <blockquote class="imgur-embed-pub" lang="en" data-id="a/MhWGX"><a href="//imgur.com/a/MhWGX">Shrike 2</a></blockquote><script async src="//s.imgur.com/min/embed.js" charset="utf-8"></script>

Makes heavy use of previously massless and dragless Ox-stats, cubic girders, and struts.

[Deddly]

I was refering to his Shrike 1 craft, which had:

"4x Ion engine, 16x 700 Xenon, 52x Wing Strake, 20x 1x6 array, 1x small reaction wheel, 1x OKTO2, 1 EAS1+Kerb"

He upgraded his design only after he was informed about massless parts.

EDIT: According to the records on the OP, Shrike 1 achieved 686 M/sec and an altitude of 26,621 metres.

Edited April 17, 2016 by Deddly

[Foxster]

You can get a Kerbal into orbit with ions and air-breathing engines alone as long as you are prepared to discard much of the craft. There is no Ox onboard this, the RAPIERS only run in airbreathing mode. Once they are out of air, the aircraft part is decoupled...

[ZooNamedGames]

I've got a 500+ part solar glider. She runs solely on Xenon power, takes off on her own power and all. You just have to survive the 500+ part count crippling aspect.

https://drive.google.com/file/d/0Bx7MSvRH-8qdXzlPT3hIaVMxaEk/view?usp=sharing

Sadly no pictures since it murders any PC it sees. Fantastic craft though  .

[Deddly]

@ZooNamedGames

I like your attention to detail and that you made it look good. Seriously though - is this supposed to take off in 1.0.5? I can't get it to go faster than 7.5 m/s and it just falls off the edge of the runway.

[ZooNamedGames]

2 minutes ago, Deddly said:

@ZooNamedGames

I like your attention to detail and that you made it look good. Seriously though - is this supposed to take off in 1.0.5? I can't get it to go faster than 7.5 m/s and it just falls off the edge of the runway.

Took off fine for me... that's odd. Try not touching the controls until you reach speed.

[Deddly]

@ZooNamedGames My theory is that you made this for KSP version .90. 1.0 changed how Isp works and each ion engine produces 0.1 Kn of thrust this close to sea level. If I can test your craft at 3 FPS on my 9-year-old laptop with a dead graphics card and neither the computer nor the game died, I'm quite confident that you can manage more than that.

I suggest giving your own craft a go

Edited April 17, 2016 by Deddly

[ZooNamedGames]

10 minutes ago, Deddly said:

@ZooNamedGames My theory is that you made this for KSP version .90. 1.0 changed how Isp works and each ion engine produces 0.1 Kn of thrust this close to sea level. If I can test your craft at 3 FPS on my 9-year-old laptop with a dead graphics card and neither the computer nor the game died, I'm quite confident that you can manage more than that.

I suggest giving your own craft a go

I likely made it in 1.0.2 before they made significant changes to the atmosphere again.

[Streetwind]

The Isp behavior change came with 1.0.0, so I doubt this ever flew in any post-0.90 version.

I mean, it probably flies just fine above a certain altitude, but it really can't get itself there. That entire cluster of ions produces less than half thrust on the runway than a single 0.90 ion engine, and the plane is very large for an ion glider.

For kicks and giggles though, it might be worth loading it into the 1.1 prerelease (for the performance) and applying the simple one-number config tweak required to restore ion engines to full thrust in the atmosphere. Just to see how it performs.

Edited April 18, 2016 by Streetwind

[ZooNamedGames]

1 hour ago, Streetwind said:

The Isp behavior change came with 1.0.0, so I doubt this ever flew in any post-0.90 version.

I mean, it probably flies just fine above a certain altitude, but it really can't get itself there. That entire cluster of ions produces less than half thrust on the runway than a single 0.90 ion engine, and the plane is very large for an ion glider.

For kicks and giggles though, it might be worth loading it into the 1.1 prerelease (for the performance) and applying the simple one-number config tweak required to restore ion engines to full thrust in the atmosphere. Just to see how it performs.

I haven't been able to test it due to the high part count but it flew fine. 

I could of used one trick of getting it to pitch up and retracting the landing gear and then deploying them to give it a push into the air. I sometimes do that with stubborn aircraft.

[Deddly]

Sorry but at 7 or 8 m/s, there is no chance that craft will even rotate, let alone get airborne. I have no doubt it worked for you in the past - pre 1.0, but it's not flying anywhere anymore without some serious modifications.

[vsully]

Pre 1.0 Ion gliders were awesome, I built ones armed with BD Armory MGs  

Unfortunately, now the closest you can get to Ion gliders is to power them with the Juno engines. I still run a few of my ion designs on a Juno.

[ZooNamedGames]

1 hour ago, Deddly said:

Sorry but at 7 or 8 m/s, there is no chance that craft will even rotate, let alone get airborne. I have no doubt it worked for you in the past - pre 1.0, but it's not flying anywhere anymore without some serious modifications.

I'll have to test since this it was working fine not too long ago.

[obi_juan]

I still making these

But for Duna, in Kerbin or Laythe don't have the power to take off 

Edited April 18, 2016 by obi_juan

[Fearless Son]

10 hours ago, Streetwind said:

I mean, it probably flies just fine above a certain altitude, but it really can't get itself there. That entire cluster of ions produces less than half thrust on the runway than a single 0.90 ion engine, and the plane is very large for an ion glider.

Sounds like it might be a prime candidate for an assisted launch system.  Maybe a couple of underslung solid rocket boosters on decoupling pylons with their tweakables set to output at reduced thrust.  Use them to drive the craft to lifting speed and let it rise as aggressively as you can manage for as long as the rockets will hold out, then drop the dead weight and engage the ions.  

[Pthigrivi]

Tried this today and even above 10k I couldn't get it to maintain lift with all the ox-stat drag. Batteries might work. Man we could use some bigger static solar panels.

[Foxster]

1 hour ago, Pthigrivi said:

Man we could use some bigger static solar panels.

In 1.1 there are bigger static solar panels that are scaled 8 times compared to the small ones.