[Stock Helicopters & Turboprops] Non DLC Will Always Be More Fun!

[selfish_meme]

2 hours ago, EpicSpaceTroll139 said:

I don't have any pics on me, but I tried switching over the bearing on my own turbofighter from a solar panel type to an RCS type. It now is able to withstand hard maneuvers, but has trouble getting off the ground for whatever reason. I think the design I chose has too much mass in the propshaft,and thus suffers from gyroscopic effects. Either that or it adjusted the COM just enough to give it extreme ground-loop tendencies.

I have just created a new arrangement of RCS balls that has given me at least better manoeuvrability. Thought this version is heavier and more capable, but with less fuel, speed record set just before it ran out.

a short range fighter

Edited August 24, 2017 by selfish_meme

[Azimech]

10 hours ago, selfish_meme said:

Problems with the last model experimental fighter prompted a redesign to improve several areas, two engines at the front was problematic because of weight distribution and wing placement. The fuselage became long and the cockpit was right at the back. The wings were very far forward, essentially floating in air because of the engines. Two engines placed serially also produced a prop that was displaced very far from the bearing, this caused issues with the light RCS bearing and made them fail easily. A twin outboard engine mounted design like a DeHavilland Mosquito was considered but would increase complexity and probably be larger and have a slower roll rate. Instead a Push/Pull design like the Dornier Do 335 has been adopted. This was the fastest piston engined German fighter produced before the end of WWII. Only a few were supplied before the end despite being given priority over many other production planes. This test aircraft is using a 4 bladed prop which has limits on it's extension and must be angled quite severely to stop over-speed on the engine. It is much better behaved, and the part count is quite low for a twin engined aircraft. The next version will move to a 5 blade design like a Griffon engined Spitfire to allow for less angle and greater deflection when deployed. Top speed undeployed is 53ms (in level flight) and the bearings do not self destruct during small maneuvers. I have some ideas on how to make the engines more durable for the next version. - Stock Aero

When a challenge starts for prop fighters, we'll be using either adjusted aero or FAR. Stock aero is just too limiting.

Also, since BDA will be flying the planes, no prop pitch adjustment can be made. This means the designer needs to find a fitting value somewhere between acceleration/climb and top speed/dive.

Unless ... as we know a kOS script exists that adjusts the prop pitch dynamically. What we don't know is if this kOS script can run with multiple planes and if not, if it can be adapted.

 

Edited August 24, 2017 by Azimech

[EpicSpaceTroll139]

@Azimech my collective script should be able to run on as many propellers and crafts as needed. I might make some tweaks to it though.

Funnily enough, for whatever reason I've been getting better performance from the engine on my turbofighter recently with fixed blades.

Edited August 24, 2017 by EpicSpaceTroll139

[Azimech]

Guys, take a look at this :-)

 

[NoobTool]

I added a retractable grapple to the Wyvern and promptly devised a torture test:

https://kerbalx.com/NoobTool/Wyvern-Retriever-+-Dirk

I was hoping to make the grapple dock in both stowed and deployed positions, but there's pretty limited space to work with between the pontoons, so it only docks while stowed for now.

The boat weighs 33tons and fits snugly inside the Wyvern's cargo bay. Maybe some of you ace pilots out there could easily snag things with the grapple, but I had a pretty difficult time even with the Vernor based RCS I added.

Seems to hold up pretty well. I'm not sure what the plan was after plucking the boat from the water...

...but we'll call it a successful test!

Edit: the grapple now docks in both positions.

 

Edited August 26, 2017 by NoobTool

[klond]

 Hello dudes.  Gotta show you some stuff.

 If you use vanes on your turbos and want them balanced you need symmetry, right.  So 2 vanes, or 3, or 4,6,8, or 12 (6x2) for stock.  I guess there's a mod for more that I should probably get.

 K, well on a small scale 2, 3, and 4 vanes don't grab 100% of the airflow; there are gaps.  This means you can power 2 things (or more) if you only use a few vanes on the first turbine in the airstream!  Very exciting!

 The other 3 things you could energize with the remainder of the air would be

 

a second rotor

 

or a tail rotor

 

or put Azimech's boost flap on there and let 'er rip.

or a combination I 'spose.

 

 Amazingly it works better than expected.  If anyone else tries or has tried it, shoot me a pic.  I would think this would scale up.

[qzgy]

1 hour ago, klond said:

 I guess there's a mod for more that I should probably get.

Editor extensions perhaps?

[klond]

4 minutes ago, qzgy said:

Editor extensions perhaps?

 Thx

[qzgy]

Just now, klond said:

 Thx

Here's the link

 

[Gman_builder]

@klond dang thats pretty cool

[selfish_meme]

I decided to do some questionable science experiments around turboshaft? engines in an effort to reduce the size and increase the efficiency of my build. I think there may be something here for all of us.

The smallest motor I have made is just able to get a small helicopter in the air using 3 Junos, using what I know now I could make that a bit more efficient.

I put together a frame and tested my most recent engines side by side

All engines have 2 junos and three 45' blades. As you can see the one on the far right has the advantage in thrust, it is also revolving fastest

I don't have an explanation for this as its shaft is much heavier than the other engines, and has a spare heat-shield doing nothing also on the engine. Two of the bearings, the heat-shield and the one next to it, are pretty much the same as the untrasmooth bearing by quitessa, the other two are my own concoctions. The smallest motor is next with the best thrust per weight, it doesn't provide as much thrust as the bigger motors but weighs a lot less.

My conclusion, the heat-shields make good turboshafts

Edited August 26, 2017 by selfish_meme

[Azimech]

1 hour ago, selfish_meme said:

I decided to do some questionable science experiments around turboshaft? engines in an effort to reduce the size and increase the efficiency of my build. I think there may be something here for all of us.

The smallest motor I have made is just able to get a small helicopter in the air using 3 Junos, using what I know now I could make that a bit more efficient.

I put together a frame and tested my most recent engines side by side

All engines have 2 junos and three 45' blades. As you can see the one on the far right has the advantage in thrust, it is also revolving fastest

I don't have an explanation for this as its shaft is much heavier than the other engines, and has a spare heat-shield doing nothing also on the engine. Two of the bearings, the heat-shield and the one next to it, are pretty much the same as the untrasmooth bearing by quietplease, the other two are my own concoctions. The smallest motor is next with the best thrust per weight, it doesn't provide as much thrust as the bigger motors but weighs a lot less.

My conclusion, the heat-shields make good turboshafts

 

Interesting ... a few of my helicopters use heat shields as blisks, instead of what the majority has adopted nowadays.

The problem with a test stand like this one: it only measures static thrust. It would be best if you'd measure every prop over a wide range of speeds.

The debug screen has the option to show the aero data in the context menu, which will give you much more info than the yellow arrows.

Edit: who is "quietplease"?

I need my morning coffee.

Edited August 26, 2017 by Azimech

[selfish_meme]

20 minutes ago, Azimech said:

 

Edit: who is "quietplease"?

I need my morning coffee.

1

quitessa I meant, I will edit the original

Oh, one other thing, the heatshield might be the most efficient transfer disk, but the fairing bases have an added advantage that you can attach the blades directly to them. This makes a more solid and stable engine, the heat shields tend to wobble more and break easier.

Edited August 26, 2017 by selfish_meme

[The_Rocketeer]

Been tinkering with turboprops again, I'm having problems with variable prop pitch because the game now isn't treating the blades as a group on one slider but as individual sliders per tooltip menu. Anybody know how to get around this?

On a related note, trim adjustments on the shaft seem to be forgotten as soon as I switch to the main craft again.

[Azimech]

5 hours ago, The_Rocketeer said:

Been tinkering with turboprops again, I'm having problems with variable prop pitch because the game now isn't treating the blades as a group on one slider but as individual sliders per tooltip menu. Anybody know how to get around this?

On a related note, trim adjustments on the shaft seem to be forgotten as soon as I switch to the main craft again.

Which version, 1.3.1 pre?
Maybe it's an idea to re-attach the blades?

[The_Rocketeer]

@Azimech I tried that as soon as I noticed this - no joy. The same problem is affecting my electric props, trim and symmetry groups both.

Latest release versionwise. I do have a string of (mostly cosmetic) mods installed, but thought I'd ask in case I'd missed something Squad had done.

[selfish_meme]

Haha, after a fevered dream last night, seriously I've got the flu, I present to you the Microturbo in a box!

That's right a Turboshaft engine in a 1.25m service bay, completely shielded from aero

Here are the inner workings, the shaft is a probe core covered in RCS balls

Yes it can lift a small chopper

This was my first try and it needs a bit of tweaking, but it holds great promise for all sorts of craft, this should easily power a plane or a few in the sort of space reserved usually for just spinning props!

Height record so far, over 700m

If you want to play with it you can get it in the usual spot. https://kerbalx.com/SelfishMeme/Microcopter

Edited August 27, 2017 by selfish_meme

[Krog34]

Hey guys, thought I'd show off 2 of my latest turboshaft projects. I've been ever improving the "Kermansky Engines" lately, now incorporating some wheels to stop the rotors from wobbling during high G maneuvers. This is has greatly improved their reliability. As of yet my engines have been high power low speed but I like the progress so far, experimenting with some dual stage propellers, we'll see where that leads 

 

The K-25 Emancipator (B-25 Mitchel knock-off)

Spoiler

K-29 Super Stronghold (B-29 Superfortress knock-off)

Spoiler

 

Edited August 27, 2017 by Krog34

[selfish_meme]

49 minutes ago, Krog34 said:

Hey guys, thought I'd show off 2 of my latest turboshaft projects. I've been ever improving the "Kermansky Engines" lately, now incorporating some wheels to stop the rotors from wobbling during high G maneuvers. This is has greatly improved their reliability. As of yet my engines have been high power low speed but I like the progress so far, experimenting with some dual stage propellers, we'll see where that leads 

 

The K-25 Emancipator (B-25 Mitchel knock-off)

  Reveal hidden contents

K-29 Super Stronghold (B-29 Superfortress knock-off)

  Reveal hidden contents

 

I think that one thing that may help you improve the speed is put nose cones in front of those fairing bases, they would be huge drag sources.

[Krog34]

10 hours ago, selfish_meme said:

I think that one thing that may help you improve the speed is put nose cones in front of those fairing bases, they would be huge drag sources.

I've an iteration of those engines that uses a nose cone and it does improve efficiency but not by enough. The Brawler Engine is more aerodynamic but still hits a wall at around 95m/s and my bearings can't handle much more than 4 panthers blowing at max on them as of now. The fastest engine I have now is actually a version of the ones on the K-25 and K-29, hitting 100m/s at 5000m and then it runs out of oomph haha!

Edited August 27, 2017 by Krog34
spelling

[selfish_meme]

35 minutes ago, Krog34 said:

I've an iteration of those engines that uses a nose cone and it does improve efficiency but not by enough. The Brawler Engine is more aerodynamic but still hits a wall at around 95m/s and my bearings can't handle much more than 4 panthers blowing at max on them as of now. The fastest engine I have now is actually a version of the ones on the K-25 and K-29, hitting 100m/s at 5000m and then it runs out of oomph haha!

100ms is good, I'm still around 50ms with my little twin Juno engines. Yours are good enough for the stock aero dogfight challenge @Azimech is thinking of running. I have a fair way to go yet in bearing stability.

[selfish_meme]

New speed record for me, dual twin Junos reaching 56ms in stock, 57+ in adjusted, and it can turn!

[NoobTool]

I have a question for the copter gods. I'm sure it has been addressed before (I'm still working my way through this thread).Why does the wheesely not work as a blower motor? I tried replacing my panther blowers with wheeselys' and they don't seem to affect the blower wheel at all. What gives?

[EpicSpaceTroll139]

38 minutes ago, NoobTool said:

I have a question for the copter gods. I'm sure it has been addressed before (I'm still working my way through this thread).Why does the wheesely not work as a blower motor? I tried replacing my panther blowers with wheeselys' and they don't seem to affect the blower wheel at all. What gives?

For whatever reason (probably having to do with complications related to their ability to reverse thrust) wheesleys (and goliaths too I think) do not have an exhaust vector. Thus they will not blow away or even nudge something placed behind them even when roaring at full throttle. So unfortunately we can't spin our turbine wheels with them, or blow away pickup trucks.

 

Edited August 29, 2017 by EpicSpaceTroll139

[NoobTool]

@EpicSpaceTroll139 

That's a shame. I figured it was something like that. Thanks for the info and the speedy reply.