Laythe Landers/Jets

[Wcmille]

What are your tips about building craft to land on Laythe? My current design is a small spaceplane with a single Rapier.

[Mikki]

I made once a rather small Mk2 SSTO with two rapiers, IIRC. Make sure you have enough pitch authority, the atmosphere is slightly thinner.
Looking for a pic... hang on... i don`t want to spoil to much, a pic from 0.9... i was  able to refuel this SSTO on ground for surface explorations, wing area was enough then... It had two rapiers and a jetengine for surface exploration. I am a stock Laythe dweller, yes.

[moogoob]

All these worlds are yours except Laythe. Attempt no landings there.

(I've only landed there once, and it was a skycrane for delivering a rover.)

[Aegolius13]

I just did a small 1 rapier plane for a Jool 5.  A few tips I came across:

You may want to add more wing than you would on Kerbin.  The surface atmosphere is thinner, and a low takeoff / stall speed will help you work with the bumpy terrain.

If you go Mk 1, I'd use the inline cockpit and put something more heat resistant in front.  One rapier can get a small plane going very fast and hot, easily enough to blow up the regular cockpit.

It did not take much LF to ascend on jet mode, so even one Mk 1 fuel tank was overkill. You could use a rocket tank and drain a little oxidizer, and/or use the precooler, NCS adapter or a Mk 0 tank to get a little fuel.

In thinner air, reaction wheels are comparatively better, and control surfaces are comparatively worse.

If you send a skilled pilot, consider leaving off a probe core to save electricity.  I just had a couple small solar panels for emergency, but relied on a 1k battery for the most part.

[Wcmille]

13 minutes ago, Aegolius13 said:

I just did a small 1 rapier plane for a Jool 5.  A few tips I came across:

You may want to add more wing than you would on Kerbin.  The surface atmosphere is thinner, and a low takeoff / stall speed will help you work with the bumpy terrain.

If you go Mk 1, I'd use the inline cockpit and put something more heat resistant in front.  One rapier can get a small plane going very fast and hot, easily enough to blow up the regular cockpit.

It did not take much LF to ascend on jet mode, so even one Mk 1 fuel tank was overkill. You could use a rocket tank and drain a little oxidizer, and/or use the precooler, NCS adapter or a Mk 0 tank to get a little fuel.

In thinner air, reaction wheels are comparatively better, and control surfaces are comparatively worse.

If you send a skilled pilot, consider leaving off a probe core to save electricity.  I just had a couple small solar panels for emergency, but relied on a 1k battery for the most part.

Are you landing mostly fueled, or landing mostly empty and refueling? My preference is to refuel in orbit, not on the surface, which does make re-entry worse from the extra mass.

[Aegolius13]

I did not refuel on the surface.  The plane did not need much fuel anyway, and ISRU would have added more weight and complexity than was worth it.

Reentry from low Laythe orbit did not get that hot, even with a full tank of fuel and a steep reentry path. It's getting to that low orbit that's problematic, if you want to aerobrake.  I did that with my mothership - burn to capture, then GRADUALLY aerobrake over successive passes to low orbit. 

[Wcmille]

8 hours ago, Mikki said:

I made once a rather small Mk2 SSTO with two rapiers, IIRC. Make sure you have enough pitch authority, the atmosphere is slightly thinner.
Looking for a pic... hang on... i don`t want to spoil to much, a pic from 0.9... i was  able to refuel this SSTO on ground for surface explorations, wing area was enough then... It had two rapiers and a jetengine for surface exploration. I am a stock Laythe dweller, yes.

Loving this screenshot. How'd you land the other two vehicles? Guessing the big one is a mobile fueler. Whats the little one?

[Wcmille]

8 hours ago, Aegolius13 said:

I did not refuel on the surface.  The plane did not need much fuel anyway, and ISRU would have added more weight and complexity than was worth it.

Reentry from low Laythe orbit did not get that hot, even with a full tank of fuel and a steep reentry path. It's getting to that low orbit that's problematic, if you want to aerobrake.  I did that with my mothership - burn to capture, then GRADUALLY aerobrake over successive passes to low orbit. 

What was your initial high orbit that you were trying to descend from?

[Aegolius13]

50 minutes ago, Wcmille said:

What was your initial high orbit that you were trying to descend from?

On my Jool 5, my mothership was transferring from Tylo.  I've also done transfers from Kerbin in standalone spaceplanes.  In either case, I could not aerocapture safely.  But once I burned into a highly elliptical orbit with periapsis in high Laythe atmosphere, and apoapsis out near the edge of Laythe's SOI, it was possible to descend with multiple aerobrake passes. 

If you can figure out how to get a heat shield in front of your ship, might be possible to aerocapture direct from Kerbin, or from a Tylo gravity assist.  

[Wcmille]

1 minute ago, Aegolius13 said:

On my Jool 5, my mothership was transferring from Tylo.  I've also done transfers from Kerbin in standalone spaceplanes.  In either case, I could not aerocapture safely.  But once I burned into a highly elliptical orbit with periapsis in high Laythe atmosphere, and apoapsis out near the edge of Laythe's SOI, it was possible to descend with multiple aerobrake passes. 

If you can figure out how to get a heat shield in front of your ship, might be possible to aerocapture direct from Kerbin, or from a Tylo gravity assist.  

I'm flying a large mothership to Jool, so just need something that can get to Laythe and back from low Laythe orbit.

[Aegolius13]

8 minutes ago, Wcmille said:

I'm flying a large mothership to Jool, so just need something that can get to Laythe and back from low Laythe orbit.

If you have a good way to get your whole package into low Laythe orbit, the actual descent itself should be fine.  I think my mothership was at 60km or so.  I did an imprudently steep reentry burn (landing less than 1/4 orbit in front of my current position) because I wanted to hit a particular island and was too lazy to go around one more orbit.  Even so, my plane held up OK heat-wise.  The nosecone intake was unsurprisingly the hottest part, but it did not come that close to blowing up.  

If you're curious, my Jool 5 mission report (including some pics and narrative of Laythe lander) is at:

 

[KerikBalm]

For almost all my SSTOs, and all of them that don't land at the KSC, I include braking chutes.

It used to be that the atmosphere was 0.8 atms, and since gravity was 0.8 Gs, stall speed was the same: this isn't the case now, the atmosphere is only 60% the pressure of Kerbin's atmosphere - the MW is the same or nearly so.

A difference that matters now (I'm pretty sure) is temperature... colder air is denser, and Laythe's atmo varies between 247 to 288 K Kerbin's temperature can reach 315 K... in the end, the landing speeds aren't so different.

A single rapier spaceplane should be fine.

I would also recommend making it capable of water landings... because... well laythe is mostly water, and you can always land near the coast and just "taxi" to shore.

[Sharpy]

I really want to deploy a permanent water-landing airplane base there - one that will not return to orbit, but can cruise whole Laythe and refuel locally.

[KerikBalm]

I was sort of developing something like that... a supercruise plane using 9000+ Isp engines.

Its the one in the background here:

The one in the foreground is the shuttle for 2.5m and smaller modules to and from orbit. The one in the background has panthers on the back of the nacelles, and thrust reversed wheesleys (its a bit exploity) for a lot of thrust for a small nacelle frontal area, with both engines getting 9000 or higher Isp.

The cargobay of both is the same:

And I developed a number of modules that fit in there. Both would use a LV-N tug to get from LKO to laythe orbit (at which point the LV-N tugs detach and function as tugs, instead of internal engines for the mk3 planes)

Spoiler

Some modules:

The panther-wheesley version lacks any propulsion capable of getting over 900m/s atmospheric or producing thrust in space (though I was considering giving it some RCS blocks or vernors and a little oxidizer storage).

I made a 2.5m "module" that could get it to orbit of laythe... but there wasn't much point to it. The module takes up the cargopay, and turns it into just a shuttle to get 4 kerbals to LLO... which is pretty inefficient givenits size... but anyway:

With the rapier payload... it could get back to orbit of laythe... to just get to kerbin orbit it needed extra engine pods which I placed externally, and decoupled in LKO... the external engine pods were in fact mini SSTOs that I could recover back at the runway.

Spoiler

(this is for Duna though, not laythe)

but for my simple "Science lander" laythe SSTO... its meant to carry the enttire laythe crew down (6 of them in my mission), and have a full science package.

Its the one here:

4 rapiers... it was overkill, 2 would have done it, I also had a 2 whiplash/2 rapier version. Notice the hydroplanes. It had trouble taking off from water, which is why I gave it more thrust - incidentally, it can also function as a sub, and it was actually easier to takeoff by diving down and then burst out of the water at 60 degrees.

I think instead I should have just adjusted the AoA that it had while skimming the water's surface... but oh well,

[DunaRocketeer]

20 hours ago, Wcmille said:

What are your tips about building craft to land on Laythe? My current design is a small spaceplane with a single Rapier.

I don't have as much experience as others in this thread with flights to Laythe, but I have recently finished a Laythe exploration mission and I agree that a small spaceplane with rapiers is a great way to go about landing there. One of my favourite recent experiences in KSP has been spiralling down to an island on Laythe, managing the glide whilst scoping out good landing opportunities. Here's how I managed my flight - I hope there will be some helpful ideas and tips :

First off, have you considered a spaceplane that lands on its tail? I found vertical landings useful when you want to touch down in a tight spot (Laythe's terrain can be a bit bothersome when it comes to finding smooth flat areas for horizontal landings.) It also makes sense from a role-play perspective; no pre-prepared runways exist on unexplored moons . I found a couple of radially mounted parachutes useful for stalling the aircraft once I chose a landing spot.

This sort of design also lends itself to utilising the 2.5m service bay, which I find to be a great container for small rovers (and other important stuff like life support and other utilities). After all, once you've made it to the surface, you're going to want to get science from a couple of different biomes - and see the view from one of the island peaks!

Finally, think about folding in additional roles for your lander - it takes a lot of effort to haul stuff out to Jool, so the more you can do with one lander the better. For example, here's an image of my Laythe lander using its mining equipment on Pol.

 

Good luck on your mission!

Edited September 14, 2016 by DunaRocketeer
Grammar

[Mikki]

16 hours ago, Wcmille said:

Loving this screenshot. How'd you land the other two vehicles? Guessing the big one is a mobile fueler. Whats the little one?

Landed the truck in a giant fairing with parachutes and powered aerocapture...  Crazy then...
The small thing was on top of it while landing, its a 9 kerbal base!!!! Yeah!!! Little skycrane on top of it!!!!! Most crazy!!!!! 

[Bomaye]

Or like this:

[FyunchClick]

No real tips per se, other than if it SSTOs on Kerbin, it'll STTO fine on Laythe. I personally like em big, like home away from home. Took this horror there in 0.9

And this one mere recently in 1.12/1.13, using USI Life Support and Planetary Base Systems parts (no pics from the Laythe part of the trip, they're on my desktop :(). It did a Jool IV.