XolotlLoki

The stock skycrane (and Curiosity's which inspired it) is really more for the landing phase, not entry and descent. But it sounds like you want full EDL from the skycrane... which explains why so many entries have such large fuel tanks. So just to be clear: the skycrane should be able to deorbit, descend, and land on Mun from a height of 40km-ish?

After agonizing over whether to vote for Xeldrak or antbin, I finally decided to vote for Xeldrak. The low TWR of antbin's lander combined with the low fuel margins was just too much in the end. Plus when I went to rescue all those brave Kerbonauts stranded in Mun orbit by my testing, I was able to refuel CROME with minimal hassle; antbin's Kerbonauts are still sitting on the surface, dreading the termination order. But of course by then voting had closed. Fortunately, my vote would not have changed the results. As a post-mortem, I took antbin's re-strutting of my ship, and added fins for roll control (which this challenge taught me could not be provided via gimbal, thanks whoever pointed that out). Craft file is here if anyone wants to take it for a spin.

I agree with pretty much everything else you said, but after trying to land on Tylo I no longer think this is true. The most efficient landing seems to be a hard de-orbit burn, followed by a fast descent and hard landing burn. The general landing algorithm is to keep velocity in m/s at 1% of height in m. This is indeed more efficient with a light, high ISP engine. However, this algorithm will never get you to the surface of Tylo, because you spend too much time descending. I only managed to land on Tylo by keeping velocity around 300 m/s above the 1% target, followed by a perfectly timed hard burn just before landing. The problem with your lander is that it can't do the necessary hard landing burn, due to its low thrust. So landing will not be overly efficient. I actually crashed the first time I tried to land your ship on the Mun, because I thought I didn't have enough fuel left to get back to Kerbin with a 1% landing. Of course, I still voted for you in the primaries, and will likely do so for the finals as well. But the already tight fuel margins were made worse by needing to do a slow landing.

I did too, but I came down on a very bad slope, and had to ride it down for a while. Good times:

I didn't test Gregrox' ship before voting, but with the large number of votes I thought I'd try it out. It was pleasantly stable during ascent and gravity turn, but it had serious trouble getting to orbit (needed some last stage boost to circle at 100km). Once I got to orbit I realized that I had a massive RCS tank and a docking port (useless for Mun direct ascent), and no landing gear (very necessary). After thinking for a minute, I decided to give it a go anyway, and try to land on the poodle's engine bell, using the massive RCS reserves to balance. I got to within 3km before running out of fuel. I might have made it had I tried landing on a higher point. I hope Giggleplex' and sgt_flyer's ships are less disappointing. As for tightening security, I'd suggest a separate primary-voting thread (or multiple threads if needed due to poll limits, with random assignment). You can start it when you have the composite image and zip file ready, and end it with a poll. Then come back to the main thread for finals. I don't really see any way around something like that.

Excellent, thank you very much for that. I've never actually heard of a space frame, but I've definitely seen them (and other tesselated triangle structures). That's extremely helpful for designing rockets. Very nice, it's much more stable now as the asparagus stages drop. I like the strut cross points.

Thanks for the review. I noticed you said that my booster stuts were not optimal; what would you consider to be the optimal strutting for this design? And what are the general principles which you use to choose optimal strutting? I usually just add struts when things break without any real design framework.

Introducing the Delta X, an asparagus-staged heavy lift booster with a direct ascent Mun lander on top. It was inspired by the Delta IV Heavy and Falcon Heavy. The craft is capable of Mun landing and return to Kerbin, all with the CSM still attached (though it can be jettisoned if desired). It includes ladders for easy Munar EVA. Delta X defines the following action groups: Toggle torque Toggle ladders Activate parachute Cut parachute I documented my Direct Ascent Mun mission. I was able to land on the Mun, and return to KSC with my entire CSM intact. I splashed down just north of the beach. Craft file.

So, you think it's okay for you to set arbitrary conditions on which planes you test, but that's not okay for me? Get over it dude, and if you want me to test yours don't deliberately leave mine out. Or at least don't whine about it afterwards. Why so serious? And if you notice, I did call out all the people who voted for Sirine. I was going to do the same for GusTurbo's voters, but at least his plane didn't crash just after takeoff for me. Very glad Ekku Zakku made it past the primaries, so I can vote for someone with good conscience

More specifically, a proper turn consists of rolling the plane in the direction of the turn, then using pitch up and yaw to do the actual turning. For example, if the roll is 45*, then 1/2 of the pitch goes to the turn (the other half pitches the plane up), as does 1/2 of the yaw (the other half pitches the plane down), so even amounts of both are used. If the angle is different, re-balance the pitch/yaw appropriately.

The problem was that your center-of-mass starts behind the center-of-lift with full tanks. It only gets worse as the tanks drain. This makes even non-aerobatic maneuvering extremely difficult. For example, trying to yaw the plane results in heavy roll, and pitching the plane results in yaw. It's just not stable with the current mass and lift distribution.

After re-testing Blaster and vetrox' planes (and mine for comparison), I voted for vetrox. By far the best handing, and a unique design. For those of you who voted for Sirine, did you actually try to fly her plane? Granted it looked cool, but for a stock plane it's deadly to its pilots.

Testing complete. I tested all planes, except for gm537 who left mine out of his testing. Now I'll go back and test my favorites again and try to decide who to vote for...

Your plane looked good and was pleasant to fly; it did all the aerobatic maneuvers, and I managed a perfect runway landing with no damage. There were some CoM/CoL/tank issues, which likely would have made the plane difficult to fly as the tanks approached empty.

Double post removed.

Almost half-way through testing, still like Blaster and vetrox the best. Probably not going to get through them all before primary voting ends.

I've finished testing antbin, Blaster, BlazeFallow, briansun1, DaveofDefeat, Ekku Zakku, El_Gato_Bandito, ethan829, Sirine, SpaceBezel, vetrox, whistlehead, Xeldrak, xoknight, and zekes. So far my favorites are Blaster and vetrox; both handled wonderfully, and I was able to land both centered on the runway (which if you've ever flown for real, is *very* important). Ekku Zakky was very close.

It didn't take off by itself in my testing. I didn't let the engine rev with the brakes on or anything fancy, just hit the throttle and didn't pitch up. And it has a nasty habit of pitching down during yaw, which makes landing on the runway very difficult.

I'm putting my testing notes on mediafire if anyone is curious to see how their plane fared.

Goliath has been updated.

Use fuel ducts to pipe the fuel from the middle to the front, then to the back. For example, if you have four tanks in series (1 in front, 4 in back connected to the engine), you wire tank 3 to tank 2, tank 2 to tank 1, and tank 1 to tank 4. This way you use the middle fuel first, so after half is gone the center of mass is back to its original place, not moved far to the back. My entry (Goliath) does a 3 tank version of this.

Introducing the Goliath, named for the Goliath birdeater, a giant bird-eating spider. This is my first BSC entry. It has been updated to include science gear and fix fuel duct issues. Goliath has a small part count, with no clipping. It demonstrates the use of fuel piping to maintain proper COG as the tanks drain. It is easy to fly (takes off with no pilot input), and has phenomenal aerodynamic performance. The design is a deconstruction of the Albatross. It has long wings contructed from a single part, two engines, and a relatively small amount of fuel. By rearranging these pieces, it achieves vastly improved performance, while looking much more interesting. Goliath defines four action groups: Toggle torque on pods Toggle intakes Toggle ladders Do science Updated craft file available here. Changes since original post: fix fuel duct issue in original build add science gear and action group