[Stock 0.16] Smallest Mun lander possible?

[Apotheosist]

Is this the smallest Mun lander possible in 0.16? With the new way the engines work, they are far less efficient than they were, so much more fuel is needed. 7 tanks in total for this one, in 15.2, only 3 tanks were needed. This one uses the Toroidal aerospike engine, whcih I think is overpowered as it has a much higher thrust to weight ratio than the other engines. It\'s already very efficient, it should be heavy to balance out it\'s efficiency. It will probably be changed soon.

Anyway give it a go and try improving on it if you want. Perhaps using jet engines early on would reduce the mass of the overall rocket?

[Monkthespy]

It was designed to be efficient. It\'s pretty balanced out until you do my designs. Then you have 4 of these babies on a stack of fuel tanks lifting even Mun landers up.

[Accelerando]

Is this the smallest Mun lander possible in 0.16? With the new way the engines work, they are far less efficient as they were, so much more fuel is needed. 7 tanks in total for this one, in 15.2, only 3 tanks were needed. This one uses the Toroidal aerospike engine, whcih I think is overpowered as it has a much higher thrust to weight ratio than the other engines. It\'s already very efficient, it should be heavy to balance out it\'s efficiency. It will probably be changed soon.

As if technology can\'t improve!

[karolus10]

It\'s smallest mun-capable spacecraft (and it\'s able to go back to kerbin with tiny amount of fuel) i built (0.16 decouplers are pretty lightweight )

(if someone think that using jet engine is cheating - putting one tank + areospike could be used instead jet engine)

[Omega500]

It\'s smallest mun-capable spacecraft (and it\'s able to go back to kerbin with tiny amount of fuel) i built (0.16 decouplers are pretty lightweight )

(if someone think that using jet engine is cheating - putting one tank + areospike could be used instead jet engine)

Awesome

[karolus10]

I tested jet engine first stage replacement and i made to minmus with this:

First stage boost lander 30 kilometers high, rest of journey to minmus and back, You could make with ~15-20% fuel left before reentry 8).

More screen-shots from trip (large;p)

[Apotheosist]

@karlous10, when I first saw your design with the jet engine, I thought 'Wow, that\'s AMAZING! Some really elegant design there. The bar has been raised considerably.' I tried it out, but I\'m not familiar with jet engines so I didn\'t get very far at all. I came back here to see you had posted pictures of an alternative design using an aerospike engine. I was very skeptical about it though. So I did some calculations. The results were: I calculated the first stage of your rocket to have 1374.9 m/s of delta-v, and the second stage to have 1298.5 m/s of delta-v. In total, this makes 2673.4 m/s of delta-v. Now, from my experience that isn\'t even enough to make orbit, with familiar numbers for low orbit to me being at least 4,000 m/s. I wanted some practical evidence though, so I tried it out anyway. I only managed a suborbital arc, which backed up my theory side.

Of course there could be many things to explain this. You could be 'cheating', and there are many ways it could be done. Or plain trolling, just lying for the fun of it. Or I could be far, far worse at this game than I thought I was, In which case I would ask you to share step by step instructions on how to fly this thing

So tell us, what is your secret? ;D

[karolus10]

So tell us, what is your secret? ;D

Secret lies in specified throttling and launch profile (I think, I could manage to made some video on YT, showing whole thing, but I had a lot work in this week, so it must wait :-X) , I wanted built (this first, jet one) craft using hybrid jet/rocket on one/half tank since 0.15 (inspired atlas booster engine shroud) but it was too heavy and it did not make even full orbit .

In 0.16 decouplers (and many other things) are considerably lighter and i tried next shot and after ~17 attempts I\'m a believer 8).

Kerbin atmosphere is very tricky one - we got serious drag to 30km and first 10k meters are most challenging (mostly because weird drag model) so i tried break 10km ASAP (but not too fast, otherwise u only waste energy) and after that, keep accelerating in most efficient way possible (in 100% throttle u drain fuel in no-time ;p).

Quick checklist How-to reach orbit (pro-grade, equatorial) with this baby:

# Pre-flight set:

- Precision mode ON (I\'m rebind to tab, because using Caps is annoying)

- SAS ON

- Map View set on KSC ,Camera full zoom and angle for seeing launch profile form back (simply hold + and arrow down) and MW navball ON

- Throttle 100%

# Engine start (jet engine full thrust after 4-5seconds)

# Clamps off after +05s

# Pitch +90* (straight UP)

# Roll program, Heading 90* (east)

# Pitching down +60* after 10k meters reached

# Change to orbital speed indicator

# Now tricky part, keep watching speed readouts... In a moment when We stop accelerating:

- Hit space (jettisoning jet engine and starting rocket motor on full thrust)

- press X to cut the engine

- SHIFT to throttle up for positive 1G on acceleration scale (no less, no more, i tried use small engine before but it\'s slightly too weak and we bleed speed achieved by 1st stage)

// Do all actions AT ONCE or simply throttle down instead for save fuel

# Keep acceleration on +1G (no less, no more) by throttling down

# Keep +60* and climb to 30k meters

# Pitching down to +40* in 30k meters

# Switching to Map View (Target orbit 80 kilometers)

# Pitching down to +20* in 50k meters

# Pitching down to +10* in 60k meters if Apogee less than 68-70km, if higher/far away, skip

# Pitching down to +00* when Apogee >= 70km or apogee is far away

# Throttle down to 0.5G for 'closing' Apogee to you, control throttle (no more than 1G) / pitch in 00-10* range for keeping it close to ship (not overshoot)

# When we get circular orbit, cut the engines since Apogee = 80km (+ 500-900m considering drag)

# Circularization burn (minimum throttle, slowly pushing apogee in few weak impulses)

Jeb done !

EDIT 1: In that way I\'m made for 80 kilometer orbit orbit with 95-98L of Fuel left.

[karolus10]

My half tank jet hybrid is also minmus capable (pictures later)

Fuel log:

[tt]200L - Launch

96.7L - Ker. Orb. 80km

91.4L - Min. plane change

73.8L - Trans-Min. Injection burn

73.0L - Min. orbit injection

72.7L - Min. Orb. 5km

71.0L - Minmus Touchdown

66.3L - Min. Retrograde Orb. A 20km; P 17km

65.5L - Ker. injection Burn (Orb. 51kk;10k)

// BUG - ship went trought kerbin on HI warp and must orbit once again :-/

65.5L - Motor seperation / Kerbin reentry[/tt]

So it made to minmus and back using only 134.5 Liters of fuel .

Fly safe !

[illectro]

I believe I have something smaller.... will post video soon.

[Apotheosist]

It\'s a bug people http://kerbalspaceprogram.com/forum/index.php?topic=17006.0;topicseen Someone managed to land on the Mun and come back on a single half tank. I just managed to get into orbit with the same configuration, with half a half tank left, but didn\'t want to go to the Mun as it would take too long. The secret lies in the low throttle setting. The lower the setting, the higher the efficiency.

[karolus10]

Problem could be solved by limiting throttle range - best engines had max 100%-40% throttle range, now we could had powerful engine for breaking the orbit and super-efficient (nearly like Ion ones) engines in one package .

So, in 0.16 good throttling could make miracles .

Edit1: Also u get to the mun in half tank in nearly same time like using 8 full tanks ;p

[greatorder]

-snip-

funny, I couldn\'t even get this to orbit the planet with mechjeb.

EDIT: I\'m afraid I have to call BS, every time I tried, I couldn\'t get that out of the atmosphere.

and for those pics- what\'s to say you didn\'t shove it on top of a different rocket?

EDIT2: the other rocket, with very good manoeuvring and a bit of luck, could get to the moon.

[Apotheosist]

@greatorder, the secret lies in using a low throttle setting. Mechjeb doesen\'t do this.

[greatorder]

@greatorder, the secret lies in using a low throttle setting. Mechjeb doesen\'t do this.

Yes. I tried the throttle being so low there was no form of acceleration, and the velocity stayed constant.

the thing couldn\'t get out of the atmosphere.

[Apotheosist]

Obviously there is a balance between low throttle setting and acceleration to get to orbit.

[Ziff]

funny, I couldn\'t even get this to orbit the planet with mechjeb.

EDIT: I\'m afraid I have to call BS, every time I tried, I couldn\'t get that out of the atmosphere.

and for those pics- what\'s to say you didn\'t shove it on top of a different rocket?

EDIT2: the other rocket, with very good manoeuvring and a bit of luck, could get to the moon.

This takes a little bit of skill and practice, but it\'s absolutely amazing. (Yeah, I know it\'s a bug.) I just hit a 165km orbit with 31.6L of fuel left. It\'s totally possible. Your problem is Mechjeb. It is not efficent for things like this. The directions he gave above are PERFECT. The only exception is I tend to start running out of air for the jet engine at 9k, so I immediately drop it as soon as I see the loss in vertical spd, everything else follow according to directions above.

-Ziff

[TheDarkOne]

What about your piloting? Did you follow what the creator of the craft said to do?

[MarkoRagnos]

I got this:

Here:

I shall call him Superman of minmus because he can leap tall rockets in a single bound

[Luke321]

landed MarkoRagnos\'s design with 0.9 liters on the mun

[karolus10]

I have some free time after work yesterday, so I made video of my craft used in field (720p), as I\'m promised. Enjoy watching .

http://youtu.be/fL-D2Yd4G1w?hd=1

[Bulletproof]

@Karlos10 nice! I have noticed some that 100% throttle isn\'t that efficient, and too low neither is. Never got to actually figure out the optimum , but you did it for me! ^^ thank you!

[karolus10]

It\'s isn\'t optimal way: I\'m fail when coming back to kerbin - I made mistake and, went into pro-grade orbit... ascend into retrograde orbit and burn from near side of min-mus gave the best effect(comparing to effort), maybe i made video from moon arcs mission later using same ship .

[iggybot6]

how would u use mech jeb on this?(im not good enough do do all the steps right)

[LaydeeDem]

how would u use mech jeb on this?(im not good enough do do all the steps right)

Trial and error buddy, trial and error. How do you think us bitter vets made it to the Mun before plugins? Anyways I assume this lander takes advantage of the fuel bug?