CLOSED -- Flying Duna AGAIN (Thanks for Participating)

[Northstar1989]

Once I get my Laythe SSTO seaplane's data back to Kerbin, I intend to leave the Kethane Travelling Circus to its own devices a bit while I experiment with Interstellar in a totally separate install. I already know the KTC save file is totally incompatible with Interstellar so installing that mod in the same game install will kill the KTC, and that ain't gonna happen until a KSP update kills it like its fathers before it.

But I seriously doubt that Interstellar will alter my approach to flying on Duna. I'm not at all interested in flying super high and super fast there. You only need to get high enough to clear MOST but not all of the mountains, and the only critical speed characteristic is being able to fly slow enough to land at what is the average terrain altitude of the planet. If you can do these things, then you can pretty much explore all of Duna in an aircraft, or fly between bases anywhere on Duna you care to put them. And that's the essence of this challenge and the reason for the minimum 2500m landing capability.

I look forward to your flotilla's arrival. And I'm glad to see more folks doing flotillas instead of single ships . Keep us posted.

KSP-Interstellar's greatest, most interesting feature IMHO is the In-Situ Resource Utilization system. There's great value to being able to produce your fuel off-planet more sustainably than Kethane allows...

But beyond that, when it comes to flying, its realistically-implemented nuclear reactors (NearFuture reactors produce far less power per ton than their real-life counterparts) open up the possibility of building larger cargo planes/helicopters on Duna- in my opinion the only type of aircraft *REALLY* worth building besides science vessels...

In fact, this thread has inspired me- once this thread dies down some and I get in all my entries, and probably once 0.24 is released and everybody's used to it, I'm thinking about creating a "Flying Duna Mk3" challenge, one rewarding cargo capacity, low-maintenance (a point penalty for using nuclear reactors instead of solar power, and no use of reactors beyond fission allowed- fusion isn't sustainable on Duna, and antimatter isn't sustainable without massive infrastructure), and low part-count, rather than Kerbal capacity.

As for altitude- well it's of obvious use for spaceplanes... Also, the higher a plane's altitude ceiling, the faster you can fly at medium altitudes relative to that ceiling (you can maintain a lower Angle of Attack). OR, the higher the theoretical cargo capacity at a lower altitude. So I've found this challenge useful for working out some design principles to eventually use in my Duna heavy lifter designs... (once again, only really possible without massive part-spam using KSP-I)

Regards,

Northstar

P.S. I made an adjustment burn on the Minmus Spacedock- which will be refueling the Raven Mk2 before it departs for Duna. The spacedock is now 3 game-days out from Minmus. I'll probably time-warp through a lot of it, rather than running additional simultaneous missions as I usually do though- so expect updates on that relatively soon.

Edited February 15, 2014 by Northstar1989

[Fengist]

Ok, as promised, a new ship flying round Duna.

The DunaFish

Ok, if you're not into a WOT then feel free to skip ahead to the pretty pictures.

It occurs to me that there are a number of huge problems flying round Duna. The first being choice of engines. As I stated very early in this thread and again with my other post, the choices are limited. Since my last plane did... ok with a Kethane/Electric mix, I decided to stick with that logic. But, where my last one came in under par with the folding props, I went a bit overboard this time with 10 props. I also took the advice you guys gave and loaded up a couple of nukes. I only really needed one but I'm into symmetry.

The result: Level flying altitude - 6300m

Level flight speed: 140 m/s

Not exactly what I'd hoped for but it stays above most of the horrendous terrain on Duna, not all, but most.

Nextly, another huge problem with Duna is that NOTHING is flat. Landing a fixed winged aircraft is like trying to roller skate on a gravel road. Since I've been playing around a lot with VTOL's lately, it only made sense to me that anything that is going to land anywhere on Duna... should be a VTOL.

And then there's that atmosphere, or lack thereof. Anything that's going to fly above the terrain on Duna is gonna need lift, and lots of it. I'd been playing with the X-wing tail-sitter design and thought it would work well on Duna, and it does glide exceptionally well.

I also included 2 KJets on this. I thot about going full electric and I'm glad I didn't. With the props getting less than 5kn sitting on the ground, their thrust wasn't enough to takeoff. But, the 2 KJets running at about 15pct power plus the props got it off the ground easily. I used 25 Kethane to takeoff, out of 2,000. That leaves a lot for landing.

Ok, so all in all, it flies, takes off and lands. The problems. Landing is terrifying. Getting spun around and getting the speed low enough for the KJets to kick in is rather tricky since the props can't do it alone. I included a bunch of air brakes and mighty glad I did. They easily slow things down enough to fire up the jets, spin around and do some reverse thrusting.

All in all, not a great score but better than my first attempt.

Kerbals 7-2=5

Kerbals Inside +1

Cargo - There's a cargo hold in there but it's empty.

Altitude - Well, it depends on whether I use the jets. But I'll only count the props: 1000 above 5000 = +1

Circumnavigation - Easily done: +1

Total = 8

Now, for some pretty pictures:

Getting off the ground - I used a 6 RAPIER pusher to get into orbit.

Test Flight - This is a new super tug I built so that I wouldn't have to launch a tug and a tanker to make it to Duna. In this test, I found out that things got really wobbly on the docking port.

Fixing Wobbles - Luckily, I packed a box of KAS struts on the nose of the tug just in case. Here's Almal out EVA applying duct tape.

Gimme that back! - This was a first, and failed attempt at landing. Here I'm jettisoning a small landing pack I had between the tug and DunaFish. By my final landing I got pretty P.O'ed at failures, so I kept this landing pack attached until almost on the ground and burnt it out trying to get stopped.

Success - Initial landing on Duna. Final altitude: 3635

Mining Crew - Here's the crew's selfie. You may notice the two things hanging under DunaFish. Unfortunately, my 'landing gear' raised my fuselage so high I couldn't get Kethane drills to hit the ground. So, I used a couple of Infernal Robotics hinges and a pipe. In the video there's a sequence of this being activated.

Chilly - And again, a shot of the Duna north pole as I do a polar circumnavigation.

Sorry for the really sucky sound quality on this video. Not sure what caused it.

Edited February 16, 2014 by Fengist

[Geschosskopf]

Ok, as promised, a new ship flying round Duna.

The DunaFish

Damn, that's an impressive beast! And it actually does something more useful than just carry a few Kerbals around. I'd count the Kethane equipment as cargo as it's useful payload. Landing at over 5600m, too! That's really a tour de force. Bravo!

Just 1 little problem. The initial landing wasn't at 2500m or above. Given all the other capabilities of the DunaFish, especially its proven ability to land at much higher elevations, I'm tempted to give you a pass on this, except for 1 thing. You mentioned early in the post about needing that small rocket stage for the initial landing.

I'm assuming this means you brought the thing down like a rocket. Can it not land like a plane to start with? That is, use the rocket for the de-orbit burn then immediately jettison it, so the plane enters the air in flying configuration, flying nose-first. At some point between entering the air and reaching the ground, the wings and control surfaces will start to work and the thing should enter its normal flying regime automatically. At this point, you can fly it around and land it normally. I always do things this way so I can land at my chosen spot, as I never hit the atmosphere in quite the right place to just end up there without correction. Doing this on Duna requires a low, flat entry profile (like start at 50km and deorbit so your path hits the surface about 1/4 of the way around Duna), followed by major airbrake usage in the latter stages to slow to flying speed before overshooting the target too much, but it does work.

But anyway, I'm hugely impressed.

[Fengist]

Damn, that's an impressive beast! And it actually does something more useful than just carry a few Kerbals around. I'd count the Kethane equipment as cargo as it's useful payload. Landing at over 5600m, too! That's really a tour de force. Bravo!

Just 1 little problem. The initial landing wasn't at 2500m or above. Given all the other capabilities of the DunaFish, especially its proven ability to land at much higher elevations, I'm tempted to give you a pass on this, except for 1 thing. You mentioned early in the post about needing that small rocket stage for the initial landing.

I'm assuming this means you brought the thing down like a rocket. Can it not land like a plane to start with? That is, use the rocket for the de-orbit burn then immediately jettison it, so the plane enters the air in flying configuration, flying nose-first. At some point between entering the air and reaching the ground, the wings and control surfaces will start to work and the thing should enter its normal flying regime automatically. At this point, you can fly it around and land it normally. I always do things this way so I can land at my chosen spot, as I never hit the atmosphere in quite the right place to just end up there without correction. Doing this on Duna requires a low, flat entry profile (like start at 50km and deorbit so your path hits the surface about 1/4 of the way around Duna), followed by major airbrake usage in the latter stages to slow to flying speed before overshooting the target too much, but it does work.

But anyway, I'm hugely impressed.

Actually, it did land above 2500. I mentioned it in one of my image captions. But below is the actual 'landed' shot showing the altitude. See, that was one of my mistakes from my first craft and I wasn't gonna do that twice.

I didn't bring it down completely like a rocket. I brought it down mostly like an aircraft. I made the initial landing PE of 18km rather than in the dirt and glided half way round the planet slowing down. I had tried several times to get the thing slowed down so the KJets would engage and I could flip around and land but I kept plowing into the dirt at the last second. Out of frustration rather than it's inability to eventually land, and considering each attempt took well over 30 minutes of gliding down, I simply said the hell with it, and left the lander attached. I flipped it around while still flying 300m/s and used it to get me down to where the KJets could take over. I only had 360 units of fuel in the pod so it was never designed to actually land the thing, just a do a deorbit and hope for the best. Hell, my first attempt, I flew around for an hour just goofing off and getting the feel of it and then screwed up when attempting to actually land.

One mistake I made, and I knew I made it when I built it, I put the air brakes on the back of the plane. That means, any time I open them up, it yanks itself into flying forward in the direction of travel. I should have put them on the nose so it would flip itself around and fly properly, backward.

Oh, and don't worry bout the kethane gear unless you want to. I think those drills are only about 1 ton each. I wasn't really shooting for any score here. If I were, I would have taken that unused cargo bay in the front section and tossed in 6 more Kerbals. I just wanted to complete your challenge in something fun to fly.

The actual first landing.

Edited February 16, 2014 by Fengist

[Geschosskopf]

Actually, it did land above 2500. I mentioned it in one of my image captions. But below is the actual 'landed' shot showing the altitude. See, that was one of my mistakes from my first craft and I wasn't gonna do that twice.

Ah yes, I misread the altimeter. Well, that's a wrap, then. Congrats and add my crappy hand-drawn challenge patch to your sig .

Oh, and don't worry bout the kethane gear unless you want to. I think those drills are only about 1 ton each. I wasn't really shooting for any score here. If I were, I would have taken that unused cargo bay in the front section and tossed in 6 more Kerbals. I just wanted to complete your challenge in something fun to fly.

Well, the kethane gear has weight and weight is a big problem with Duna planes. And you could use the DunaFish's kethane gear to supply other things on Duna, which is pretty much analogous to bringing cargo to them. So I'll give you 2 points for that, 1 ton for each drill.

So, 5 points for 5 extra Kerbals, 1 point for them all inside, 2 points for cargo, 1 point for altitude, 1 point for circumnavigation = 10 points. Well done.

I assume this goes in the Interstellar category due to the generators?

[Fengist]

I assume this goes in the Interstellar category due to the generators?

Umm, let's see. The only generator I used was on the tug and that was from the IonHybrid pack. As for stuff on the plane, I used these mods:

B9, of course.

Firespitter

Kethane

Infernal Robotics and Dromoman's robotic arms for the drills

and the reactors were from NearFuture as I think you and Northstar suggested.

But you're free to put it wherever you wish.

[Northstar1989]

That's an impressive craft!

Umm, let's see. The only generator I used was on the tug and that was from the IonHybrid pack. As for stuff on the plane, I used these mods:

B9, of course.

Firespitter

Kethane

Infernal Robotics and Dromoman's robotic arms for the drills

and the reactors were from NearFuture as I think you and Northstar suggested.

But you're free to put it wherever you wish.

Geschosskopf, why is this currently in the Interstellar category? It clearly doesn't use any parts from KSP-Interstellar.

Regards,

Northstar

[Geschosskopf]

Geschosskopf, why is this currently in the Interstellar category? It clearly doesn't use any parts from KSP-Interstellar.

Well, I'll put it in regular then. I thought those reactors were Interstellar.

[StevenRS11]

I see this is still alive, yay! I have some new ideas for this, as well. Maybe I can find some time to send some of them to duna, and update my scores for .23. Ive also been using AJE lately, and am curious to see if I can make an ssto with that.

[Geschosskopf]

I see this is still alive, yay! I have some new ideas for this, as well. Maybe I can find some time to send some of them to duna, and update my scores for .23. Ive also been using AJE lately, and am curious to see if I can make an ssto with that.

The more the merrier. Northstar keeps tantalizing us with his many designs but so far none have actually made the trip.

I had to start over from scratch in 0.23 and now have a Duna base in a much less-favorable location. The altitude there is 3400m and it's extremely hilly. Still, flying is way better than driving so I've had to build a Duna plane to work there. Voila:

This one is a much smaller and more elegant thing than my old D'OH. This one is a total kethane-burner, using the generator to run the Firespitter electric props, which have an action group to reverse their thrust (now that I know about that ). Due to the demise of B9, it has a plethora of stock wings. It flies WAY better than the D'OH in all respects. It can take off without needing an upramp, actually turns in the desired direction without much struggle or desire to lose altitude, can land at much higher elevations at a slower speed, and stops in a much shorter distance. Plus the 2 Kerbals now have enclosed seating. I'm not sure about the range, however, as it doesn't have a single solar panel. But OTOH, the landing wheels have motors in them so it can rover back to base if need be .

[StevenRS11]

Some of northstars designs have more research put into them than I put into my exams. I swear he is going to find a way to fly the VAB to duna eventually. And that looks really cool! It reminds me of the old tri-plane designs from the early days of aviation.

[Geschosskopf]

And that looks really cool! It reminds me of the old tri-plane designs from the early days of aviation.

Heheh, and I thought the D'OH looked like a WW1 bomber.

This new one, which I call the DIRGE (Duna Intel & Recon Generator Electroplane) is actually a "quinqueplane" I guess. It looks a little more modern from the top:

You can see how it's built better from this angle, thanks to a Kerbal acting as a portable floodlight

The thing's got a stupid amount of lift. In the thick air of Kerbin, it's hard to make it stop flying. This allows you to do really crazy things like land on that spike-like island the next SSW of Airbase Island.

It can't do this sort of thing on Duna, of course, but it comes as close as Duna allows.

[mellojoe]

Marking this thread.

I'm starting a Duna project, and I would love to get a plane to work. I'm having trouble. Any tips right off the bat? Trying for mostly stock, so ION engines and a ton of solar panels.

[Geschosskopf]

I'm starting a Duna project, and I would love to get a plane to work. I'm having trouble. Any tips right off the bat? Trying for mostly stock, so ION engines and a ton of solar panels.

Welcome to the madness .

The 1st few pages of this thread spell out the general problems you have to overcome. Just entering the atmosphere and flying around can be done fairly easily. The real tricks are 1) being able to fly extremely slowly at high altitude so you can survive the landing, and 2) having met #1, getting the thing off the ground at Kerbin. Anything with enough wing to make a survivable landing in the 2000-3500m high dune fields that cover 80% or so of Duna is a real beast to launch because the lift wants to pull the rocket over or break it apart in Kerbin's thick air. The above DIRGE I posted had to be dragged up backwards so its wings functioned as the tail fins for the rocket, like this:

Anyway, if you want to do ion power, look in the leader board of the 1st post. There's a link to Sirene's entry, an all-stock ion thing. That should give you a good idea of what you need.

[mellojoe]

So, here's a question:

Can anything TURN while flying Duna? i've been using "hyperedit" to test some designs, and basically I'm figuring out that basically everything is just a straight shot. Turning basically is like turning a rocket, everything on Duna is more like orbital mechanics than actually flying using aerodynamics to turn.

[Geschosskopf]

Can anything TURN while flying Duna? i've been using "hyperedit" to test some designs, and basically I'm figuring out that basically everything is just a straight shot. Turning basically is like turning a rocket, everything on Duna is more like orbital mechanics than actually flying using aerodynamics to turn.

Sure, you can turn planes. It's just a lot more difficult than it is on Kerbin. My D'OH, for example, the turn radius of my old D'OH was about 5km combined with a loss of 2-3km of altitude. My new DIRGE, however, can do a U-turn only about 2km wide and not lose any appreciable amount of altitude, but it's a much lighter plane with a lower wing loading and rather more control authority for its size.

Control surfaces, like wings, are much less effective on Duna because there's less air for them to work with. So you need beaucoup control surface area, way more than for the same plane on Kerbin, to get any real control authority. But even with lots of control authority, you don't want to use a lot at any one time. Your plane is more or less riding the edge of a stall most of the time it's flying so you want to avoid sudden maneuvers. Also, fixed vertical tails are less effective at keeping the plane pointed forward so you need more of that than on Kerbin, too. Finally, there's a much greater tendency to lose lift when banked.

The last 2 things hit you from both directions. Banking causes altitude loss but keeping the wings level and trying to kick your nose over with rudder just makes you fly sideways because the tail fins neither weathervane you back prograde nor force prograde to match your new heading, unless you've got ridiculous amounts of both. It's thus usually best to make coordinated turns in segments. Bank about 20^ and then give it a little up elevator and inboard rudder at the same time. This should swing your prograde path around 10^. Check your vertical speed and altitude. If they're OK, keep the bank the same and blip elevator and rudder again. Otherwise, level off and regain some altitude before turning a bit more.

All these control issues get worse the bigger and heavier the plane is. The heavier the plane, the more momentum it has, so the more it wants to keep going in the same direction despite controls angling the nose in a new direction. And also the more altitude it will lose in turns, and the harder it is to stop.

[DaMichel]

Hi there. Cool challenge. I take it on with my K10-Korhog in style

It took many attempts and design tweaks until i finally managed to land it above 2500m. It just glides forever and if it goes too slow it becomes unstable and stalls. The only way to stop it fast enough is with reverse thrust from the propellers. Which is pretty cool. I didn't realize at first that Firespitter props have this.

Still need to deliver it from Kerbin to Duna as hose tests were done with Hyperedit. Also this needs more pics with flight stats.

I wonder, a tiltrotor craft would be okay, wouldn't it?

I figure such a design - with Infernal Robotics - would be much much easier to land thanks to its STOL capabilities.

[Geschosskopf]

Hi there. Cool challenge. I take it on with my K10-Korhog in style

Glad you find this a worthy challenge. Welcome to the madness

That is IMHO the best-looking entry so far. Should you end up tied with somebody, I'll give you the edge on looks. And should anybody say this is pure subjective favoritism, hear me out. Back in Desert Storm, an over-zealous A-10 pilot killed several of my friends so I still move (quickly) towards cover whenever I see one flying in my general direction. But I've never held that against the machine itself--guns don't kill people, it's the guy on the trigger. I can't help it if the A-10 combines an enviably austere and elegant, totally Cold-War-for-now-but-come-the-day functionality with the timeless machismo of a battleax.

It took many attempts and design tweaks until i finally managed to land it above 2500m. It just glides forever and if it goes too slow it becomes unstable and stalls. The only way to stop it fast enough is with reverse thrust from the propellers. Which is pretty cool. I didn't realize at first that Firespitter props have this.

Nor did I, or the D'OH's landings wouldn't have been such adventures .

I wonder, a tiltrotor craft would be okay, wouldn't it?

Absolutely. The rules expressly state that helicopters are OK along with airplanes. Tiltrotors are airplanes and helicopters as the mood strikes them.

[mellojoe]

Back in Desert Storm, an over-zealous A-10 pilot killed several of my friends so I still move (quickly) towards cover whenever I see one flying in my general direction. But I've never held that against the machine itself--guns don't kill people, it's the guy on the trigger. I can't help it if the A-10 combines an enviably austere and elegant, totally Cold-War-for-now-but-come-the-day functionality with the timeless machismo of a battleax.

First off: sucks to hear. Next drink is on me. I knew plenty who went over in Desert Storm, and thankfully they came home. I'm sorry you had to say goodbye to mates there.

Secondly: I, too, love the A-10. And comparing that majestic beast to a battle-axe is about the most appropriate analogy I've heard in a while. yeah, its old, yeah its outdated, but she gets the job done, and by-god she's good at it.

[Geschosskopf]

First off: sucks to hear. Next drink is on me. I knew plenty who went over in Desert Storm, and thankfully they came home. I'm sorry you had to say goodbye to mates there.

Thanks for the drink. But no worries. None of us expected to come home anyway and at least my friends have been drinking in Valhalla while I've just been getting old and gimpy .

Secondly: I, too, love the A-10. And comparing that majestic beast to a battle-axe is about the most appropriate analogy I've heard in a while. yeah, its old, yeah its outdated, but she gets the job done, and by-god she's good at it.

That plane ain't quite as old as me and there's been nothing since that's done the same job as well.

[DaMichel]

Glad you find this a worthy challenge. Welcome to the madness

It is indeed and i wanted to get something flying on Duna eventually anyway

That is IMHO the best-looking entry so far. Should you end up tied with somebody, I'll give you the edge on looks. And should anybody say this is pure subjective favoritism, hear me out. Back in Desert Storm, an over-zealous A-10 pilot killed several of my friends so I still move (quickly) towards cover whenever I see one flying in my general direction. But I've never held that against the machine itself--guns don't kill people, it's the guy on the trigger. I can't help it if the A-10 combines an enviably austere and elegant, totally Cold-War-for-now-but-come-the-day functionality with the timeless machismo of a battleax.

Oh, i'm sorry. Have my condolence. The plane ended up looking like an A-10 by - well, i guess similar design goals. The cockpits makes up half of the planes weight, so the engines went rearward to balance the weight in the front. High aspect ratio straight wings give good low speed performance. Playing with FAR, i learned that vertical stabilizers are a good thing so i added two of them.

I think with FAR it might be a little bit more difficult to land on Duna because FAR tends to apply less drag than stock and planes can stall which IIRC is not possible in stock. Hence thrust reversal FTW!

Edit: Inadvertently deleted the old images. Now here is my final entry.

Javascript is disabled. View full album

Edited March 21, 2014 by DaMichel

[DaMichel]

Hm this thread needs more love. Here is a pic of another design. The Kultra-Light Mk1 was in development before the K10 actually. I felt like making an improved version of it.

Mk1:

Flies well on Kerbin and high on Duna. But landing is super hard. It gets thrown around very easily. Perhaps the problem is with the landing gear or the fact that it sits on the runway with an angle of attack. It is also prone to tail striking when things go wrong and it has little control authority.

Mk2:

I increased the size of the control surfaces for better maneuverability. I tried to shorten the wing span also but then it wasn't able to fly high enough any more. Maximum altitude is around 7800 m with two kerbals on board. It sits straight on the runway which should result in reduced lift once touched down. The tail was redone so it can pitch up properly and with little risk of tail striking. It actually works much better for the landings. I manage landings between 2500 und 3000 m most of the time now.

Due to a bug in Pwing control surfaces i will probably either relaunch either the K10 or use the Kulta-Light Mk2.

[Geschosskopf]

@ DaMichel: Making progress I see. Nice looking planes. Good luck ironing out the bugs.

[DaMichel]

Already had made a fix for myself so the control surfaces would work properly. I hope DYJ will soon have time to look into it.

Anyway, i edited the previous album to have the complete entry for this challenge. (http://imgur.com/a/hEEOj)

I use a new plane - the K11 - and a new launcher. The launch with this was really easy. Just needs a bit of fuel pumping around.

* Two Kerbals

* Intitial Landing was a bit too low altitude. Made a quicksave then took off and flew to a higher altitude just above 2500m.

* Maximum altitude attained 8000m. Can easily cruise above 7000.

* Can fly indefinitely on the day side due to beeing solar powered. (Which is strange because on Kerbin i run out of electricity at full power) Can also cuise high enough to get anywhere on Duna.

That should be:

1 (Kerbals inside)+2 (altitude)+1 (FAR)

Not that it would matter because the plane was not made to break any records.

[DaMichel]

More of this good stuff. Here is a STOL tiltrotor craft. Not only does it look cool, it actually works. I think it can hover below 2000m. Above that, it still has nice short takeoff and landing capabilities. The best thing is that when you cut the throttle it just sticks to the ground since most of the lift is gone. No more bumping around.

Uses the Infernal Robotics mod for the tilting. Each engine nacelle is between two rotatrons which are rotating in opposing directions. Hence the wing piece on the outer end stays put. I used struts to attach it further to the large forward/rear wings. To my surprise this worked flawlessly. Only problems arise when you put struts between parts which actually move relative to each other.

Obviously i make excessive use of PWings. 'got to love these

P.S. This is not for the challenge. I wanted to show it off