Ion glider collier trophy!

[The_Rocketeer]

Latest effort, keeping you on your toes Slashy.

I'm getting rapidly airborne at about 12-15m/s, and then climbing steeply, but I find the acceleration is just too slow for the remaining fuel above 20,000m. I'm thinking I should drop a few more wings on the next run. Strange, til now more wings has tended to be an improvement.

FWIW, this was the Shrike III.

[GoSlash27]

http://cloud-4.steampowered.com/ugc/547513665804336015/034CAC967CA67031B12B9D8FDE351EBDED10AB7C/1024x640.resizedimage

Latest effort, keeping you on your toes Slashy.

I'm getting rapidly airborne at about 12-15m/s, and then climbing steeply, but I find the acceleration is just too slow for the remaining fuel above 20,000m. I'm thinking I should drop a few more wings on the next run. Strange, til now more wings has tended to be an improvement.

FWIW, this was the Shrike III.

Good run. I'll get the leaderboard updated for you.

I don't know how many wings you've currently got. Previous runs show that for your configuration (4 engines 8 tanks) the optimal number of wings should be in the neighborhood of 20-24. Counterintuitively, you may have better luck with 7 or even 6 tanks. It should make up for the reduced flight time by improved climb performance and acceleration.

Congrats,

-Slashy

[TheBedla]

I've got nothing to contribute, but let me just briefly express the amazement and respect you guys stirred in me. When lurking around this thread I felt as if I was watching Chuck Yeager "push the envelope" towards Mach 1.

This is what I find the best about the KSP community, and humans in general - having enough dedication and imagination to push what is possible further on.

[The_Rocketeer]

Shrike III had 24 wings and 8 tanks. Shrike IV will hopefully run later today with 20 wings and 9 tanks (built last night but it got past my bed time).

I want to try to keep within the hour on flight time (last run took off almost as soon as the sun was showing and was close to sunset at bingo-fuel), because turns are so inefficient. Also 90 minute flights get really, really boring. I reckon that means I need to boost acceleration, which either means cutting out drag (tanks and wings) or adding thrust (engines).

Another thought that crossed my mind was raking the wings up about 10 degrees so the thrust vector is nearer horizontal at higher altitude. Do u think that would work? Thrust would be tackling drag more directly (rather than losses to mass), but drag could be slightly higher overall...

EDIT: Bedia, Chuck Yeagar? What I wouldn't give for that guy's thrust :wink wink:! Still, thanks for the morale boost

Edited November 14, 2014 by The_Rocketeer

[MabDeno]

Shrike III had 24 wings and 8 tanks. Shrike IV will hopefully run later today with 20 wings and 9 tanks (built last night but it got past my bed time).

I want to try to keep within the hour on flight time (last run took off almost as soon as the sun was showing and was close to sunset at bingo-fuel), because turns are so inefficient. Also 90 minute flights get really, really boring. I reckon that means I need to boost acceleration, which either means cutting out drag (tanks and wings) or adding thrust (engines).

Another thought that crossed my mind was raking the wings up about 10 degrees so the thrust vector is nearer horizontal at higher altitude. Do u think that would work? Thrust would be tackling drag more directly (rather than losses to mass), but drag could be slightly higher overall...

I agree with the flight time, my best runs all had around 42-47 minutes of fuel.

I've never tried raking the wings, the benefits you gain at high altitude might be offset by more drag at lower altitude but it could be worth experimenting with.

[GoSlash27]

I agree with the flight time, my best runs all had around 42-47 minutes of fuel.

I've never tried raking the wings, the benefits you gain at high altitude might be offset by more drag at lower altitude but it could be worth experimenting with.

I forgot all about answering this! Sorry, Rocketeer!

I have never had any success with altering the static angle of attack of the wings or thrust angles. It seemed to throw off the static balance so bad that my results were worse than just leaving them straight.

AFA the tank/ engine ratios, all of my best results came from keeping the flight time at 35-40 minutes. Any more than that and the added mass and drag outweighed the advantage of additional flight time.

Best,

-Slashy

[GoSlash27]

TheBedla,

Thanks for the kind words.

This was originally intended to answer the question of whether an Eve SSTO was possible using wings and ion engines. Clearly, it's not. And ion SSTO is never going to be cost- effective from Kerbin, since conventional fuels are so much cheaper and easier.

Now it's just down to doing it for the sake of doing it, but I think what we're doing here will have a positive effect on the development of lighter, cheaper, and more efficient SSTOs using other propulsion systems.

Besides... it's kind of addictive! Sure you don't want to try your hand at it?

Best,

-Slashy

[Tsevion]

I have never had any success with altering the static angle of attack of the wings or thrust angles. It seemed to throw off the static balance so bad that my results were worse than just leaving them straight.

For most of my best runs I had a static angle of attack of 15%... and Slashy and I ended up with similar results... so I'm guessing the difference is fairly negligible in any case.

[GoSlash27]

Last run of the YERTL.

31,340@ 1,271.

I have learned how to set up a flying wing so that I no longer need a vertical stabilizer, but this one had the mass spread out too wide, setting up a horrible yaw oscillation. It was also underpowered.

My next design will use a similar wing layout, but will cluster the mass closer together. Hopefully this will give me better control with my puny torque.

Best,

-Slashy

Edited November 15, 2014 by GoSlash27

[The_Rocketeer]

My latest runs with the Shrike IV and V were less successful than the III. (IV: 9 tanks and 20 wings, V: 7 tanks and 20 wings - both had 4 engines).

Cutting wings from 24 to 20 doesn't seem to have affected climb-rate very much, but it could be part of the reason I'm not getting as good overall performance.

I'm beginning to run out of ideas. However, mabdeno's better performance with more engines makes me think this could be the way to go. I'm considering an attempt that uses optimal aero-lift and low power settings to gently lift a much heavier thrust package to the thin atmosphere and then make a massive push for acceleration. I'm sure this idea is full of pitfalls...

[GoSlash27]

New official records for Manned.

(edit) Update: http://i52.photobucket.com/albums/g13/GoSlash27/KSP/kTHULU/Kthulu3_zps56ea751f.jpg

36,006 @ 1,785

This one is at 26 wings, 4 engines, and 7 tanks. I spent 10KG to get the small reaction wheel, but this meant I had to put on a battery so no bonus.

Best,

-Slashy

Edited November 16, 2014 by GoSlash27

[Tsevion]

I'm back in in action... and I've alllllmooostt made the manned to orbit... and while I didn't quite, I think this is a new top manned record. About 150 m/s more dV and I'd be there.

Here's the Ionic Symphony VI

Max Altitude: 48,386m

Max Speed: 1976 m/s

6 engines

12 tanks

40 wings

many batteries to handle both the early morning and the night... so no bonus.

Javascript is disabled. View full album

[GoSlash27]

Tsevion,

Glad to have you back!

Updating the leaderboard now.

I'm right behind ya.

36,340@ 1,802 using 4 engines, 7 tanks, and 28 wings.

http://i52.photobucket.com/albums/g13/GoSlash27/KSP/kTHULU/Kthulu4_zps312b8b44.jpg

The rest of these are unofficial. I'm adding this info as I tinker to keep track of the gains.

36,876@1,823 using 4 engines, 7 tanks, 30 wings

36,611@1,797 4 engines, 7 tanks, 32 wings.

Best,

-Slashy

Edited November 16, 2014 by GoSlash27

[Tsevion]

Gah... pushing it even closer with the Ionic Symphony VIII:

53,271@ 2,000 using 6 engines, 12 tanks, 42 wings... pretty much the exact same craft with two more wings stuck on...

http://i.imgur.com/Ih9JP6p.png

I gotta get to bed though, it's 6 am here and these runs take a while.

[GoSlash27]

Jumped from 4 engines to 6, but it didn't gain me much. This last few hundred m/sec is gonna be a pain

39,152@ 1,938. 6 engines, 10 tanks, 48 wings.

[The_Rocketeer]

I swear to god, every time I check a new post on this thread my heart stops while the page loads in case someone's actually made it.

Talk about a space race!

[MabDeno]

OK then latest attempt, the Tripple Dart! 6 Engines, 11 Tanks and 44 Strakes

Javascript is disabled. View full album

Computers having trouble with 500 part count, might have to try a different design.

Edited November 17, 2014 by MabDeno

[Tsevion]

Well, still not quite to orbit, but now I've gotten to both orbital heights and orbital speeds... just not quite at the same time. At this point I think I'm like 50 delta-V off. I ran multiple variations of the second half of the flight, setting new records for speed and height (on separate runs). I also made the first full circle of the globe and landed back at the space center after some tumbling... and on that run I had technically an orbit... 68km x 2km... not quite a real orbit though.

The Ionic Symphony IX

Max Speed: 2124 m/s

Max Altitude: 70,459 m

6 engines, 12 tanks, 44 wing strakes.

So... darn... close... I can taste it.

Adding more wing is weird... it makes the climb to 15km slower and less efficient, and past about 35km and 1600 m/s, wings aren't doing much, they're just drag and mass... but for the 20-35km climb, more wings makes it much easier, making up for the losses. I may experiment with even more, but I think I'm reaching the point where the extra mass and drag stops being made up for.

Javascript is disabled. View full album

Edited November 20, 2014 by Tsevion

[GoSlash27]

Leaderboard is updated.

MabDeno,

Computers having trouble with 500 part count, might have to try a different design.

That's the tough part. We know the parts will do the job, but can it be done without overloading the game?

Tsevion,

You're just a stone's throw away now. I'm pulling for you, 'cuz I'm not close.

Best,

-Slashy

[The_Rocketeer]

Unfortunately I think I'm out of the running on this. Uni assignments have caught up with me and these runs just eat too much time out of the day. I'm also only making moderate gains per design revision, and others are now just a kiss from the goal, so it's unlikely I'll get a big enough lift before someone else makes true orbit.

I've really enjoyed being in this process though, I feel like everyone who submitted an attempt has contributed to the final design a little. Wing:fuel:engines ratio information alone is invaluable.

[Yakky]

Well, still not quite to orbit, but now I've gotten to both orbital heights and orbital speeds... just not quite at the same time. At this point I think I'm like 50 delta-V off. I ran multiple variations of the second half of the flight, setting new records for speed and height (on separate runs). I also made the first full circle of the globe and landed back at the space center after some tumbling... and on that run I had technically an orbit... 68km x 2km... not quite a real orbit though.

The Ionic Symphony IX

Max Speed: 2124 m/s

Max Altitude: 70,459 m

6 engines, 12 tanks, 44 wing strakes.

So... darn... close... I can taste it.

http://imgur.com/a/TOCfC

Tsevion, you might be able to eliminate your battery weight by flying a polar flight path that keeps you in permanent daylight and then turns into a traditional eastbound path for the final orbital push. That's the strategy I used with my orbital ion glider (which was under FAR aero so didn't qualify as an official entry). Anyway, here's a pic showing my trajectory... hope it helps. Good luck!

Edited November 18, 2014 by Yakky

[Tsevion]

Tsevion, you might be able to eliminate your battery weight

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.

Edited November 18, 2014 by Tsevion

[TheBedla]

TheBedla,

Thanks for the kind words.

This was originally intended to answer the question of whether an Eve SSTO was possible using wings and ion engines. Clearly, it's not. And ion SSTO is never going to be cost- effective from Kerbin, since conventional fuels are so much cheaper and easier.

Now it's just down to doing it for the sake of doing it, but I think what we're doing here will have a positive effect on the development of lighter, cheaper, and more efficient SSTOs using other propulsion systems.

Besides... it's kind of addictive! Sure you don't want to try your hand at it?

Best,

-Slashy

Thanks for the challenge, but I don't really have the patience. I currently have only very limited KSP time available, and this exercise would require considerable amount of it. I currently experiment with the 6.4x Kerbol system, so that comes with its own set of challenges - I haven't managed to get a spaceplane anywhere near orbital velocity yet in the 6.4 scale, so I'll stick with that.

Keep it up though, I'll keep watching from the shadows!

[Tsevion]

Ahahahahahahahaa... Finally... after many many hours... Success!

The Ionic Symphony XI, delivers a Kerbal to a 70km x 77km orbit with enough spare fuel to de-orbit as well.

6 engines, 12.5 tanks (12x700 and 1x400), 46 wing strakes.

The real pain was finding the right flight profile... thank Squad for in-flight quick-save, although there is a finicky bit where you lose 5-10m/s of vertical velocity on quick-load... which hurts... but still useful for comparing flight profiles at different points as opposed to having to redo the whole run each time. My final flight profile was approximately:

14° up to 10km

18° up to 20km

24° until I hit about 1700 m/s at around 40km

15° until desired periapsis is hit.

Craft File

I wanted to land at KSC, but it lost control around 25km and plunged to near the ground, I was only able to right it around 1500m up... so I just hand to land there.

Javascript is disabled. View full album

[astrobond]

Congrats !!!