Tarmenius

Actually, I don't mind the spooling up time for lift-off. It's more about those moments when you're descending too fast and by the time the engine speeds up and acceleration kicks in, you've already crashed. So, I suppose it isn't a matter of power, but of responsiveness. Guess I worded it wrong originally I love the jet-powered VTOLs. In fact, the Bullfrog is the only VTOL in my hangar that's rocket-powered. Reviews would have been orders of magnitude more difficult for me had the target Stock craft not been "Rocket-powered." And thanks to everyone who voted for the Bullfrog! I'm genuinely very surprised to have placed 3rd. As for the final vote, I chose MiniMat's SnackWagon. The pre-set thrust limiter with notes on that in the description was really what set it above the Pack Mule in my mind. It's going to change how I design my craft in the future, for sure.

So, I spent a good two-and-a-half hours briefly testing each craft and making notes about my impressions. Before I list those notes, I'd like to comment that all the crafts were interesting and each had their own merits and unique characteristics that made them fun to play with. It was very cool to see the variety of design styles derived from a single (though somewhat vague) purpose. I would also like to lay out my own criteria for determining a craft's worthiness to shed some context on why certain craft received certain overall ratings. First and foremost, as we are attempting to replace the Rocket-Powered VTOL, I significantly penalized craft that did not use rockets for their primary propulsion. This resulted in otherwise Good designs being ranked Poor. I'd like to stress that without that criteria, many of the crafts here would be Good or Excellent. Secondly, as these craft are meant to be potential Stock craft, ease-of-use and simplicity-of-design are also key. I considered how easily a relatively new player could visually dissect the design (without taking it apart) before reverse-engineering it through disassembly. Thus, crafts with much part-clipping or advanced construction techniques were also penalized to some degree. Those two considerations really drove my analysis of each craft, with some importance also placed on the standard criteria (maneuverability, flight range, Thrust-to-Weight Ratio, etc). So, having said all that, you will find my notes below. The template is NameofCraft (Author): Overall Rating (Excellent / Good / Fair / Poor / Terrible) followed by 4 main observations. Wenhermobile (Andrew Hansen): Fair - Four different flight modes may be daunting to new pilots, particularly when analyzing AG tab + Clever placement of jet engine and good overall design - Jet and Jet/Rocket modes underpowered + Rocket-only mode handles well and has sufficient power Rocket VTOL (briansun1): Poor (only because of non-rocket propulsion) + Interesting design aesthetic (Nice use of radial hardpoint instead of clipping!) - Non-rocket propulsion + Good balance of torque - Side fuel tanks don't drain VTOL Ostrich (DisarmingBaton5): Poor (only because of non-rocket propulsion) + Great-looking - Non-rocket propulsion - No description, Action Groups, or emergency safety system + Nible, responsive handling Damselfly (Giggleplex777): Fair/Poor (great design, but jet is primary engine) + Awesome-looking (near-future-looking greatness) - Rocket or Jet propulsion, limited rocket-only range (jet is primary engine) + Very agile + No other noticable flaws Morpheus (Kashua): Poor + Interesting engine configuration (forward flight by engine rather than pitch) and overall design - Underpowered vertical flight (barely gets off the ground) - Too little torque - Necessary transfer to command seat is cumbersome and may confuse new pilots. LLTV_The flying bedstead (Majorjim): Poor (Non-rocket propulsion and complex design) + Awesome homage to Lunar Lander test - Non-rocket propulsion - Complex design may be difficult for new pilots to reverse-engineer + Cool factor Kerbol Flying Object (mhoram): Terrible (part-count) + Neat UFO design - Restrictive part-count - No description or use of Action Groups - Complex design may be difficult for new pilots to reverse-engineer Snack Wagon VTOL (MiniMatt): Excellent + Great design aesthetic (Nice use of radial hardpoint instead of clipping!) + Good description/tips (Note: Cannot re-activate engines after abort) + Use of pre-set thrust limiting gives good flight time while retaining lifting power + Responsive and agile: great to fly Rocket-powerVTOL2 (PDCWolf): Poor (Power / Torque) + Good-looking extension of original design - Abort doesn't detach side tanks - Underpowered (barely gets off the ground) - Too little torque (even with RCS) VTOL Training Or Learning (Psycix): Fair +/- Simple design is easy to use, but teaches new pilots little - No description or use of Action Groups (though simple design doesn't need AG) + Responsive with plenty of power - Limted flight range PackMule (Ravenchant): Excellent + Nice, compact design + Plenty of power and torque + Good flight range + Can't think of anything negative to comment on LeapFrog LV-I VTOL (SaplingPick): Fair/Poor + Flying turtle! + Good power and torque - Hidden structure makes reverse-engineering difficult - Limited flight range Tern (SparTwo): Poor (Non-rocket propulsion and complex design) + Coolest-looking - No description - Non-rocket propulsion + Responsive and agile: great to fly VTOLPV7_1 Rocket Chair (sploden): Fair + Otherwise simple design (except for transfer to Seat and ejection system) + Plenty of power and sufficient torque - Command Seat makes NavBall hard to use (new pilots might not know how to switch control) - Aside from Eject System, basic design teaches new pilots little Omega 16 (ThePsuedoMonkey): Good + Interesting design layout + Plenty of power + Good flight range - Great pitch authority, poor yaw and roll authority (even with RCS) Pavo VTOL (UpsilonAerospace): Good + Beautiful design +/- Average flight range (good for a couple minutes of fun) + Stable design with sufficient torque (with or without RCS) - Abort System seems dangerous (though fun!) CRPLTV (Xeldrak): Fair +/- Simple design is easy to use, but teaches new pilots little + Great use of girder segment for RCS control authority + Plenty of power and maneuverability +/- Average flight time H_A_L_O (Romphaia): Poor (only because of non-rocket propulsion, would be "Good" otherwise) + Very creative design - Non-rocket propulsion + Very responsive and agile + No other noticeable flaws Again, I just want to stress that even craft marked "Poor" were fun to play with and would likely receive Good or better were it not for my Rocket-Powered focus. I had fun testing all of these designs, and each one would be a welcome addition to my Hangar.

Thanks! I wasn't sure what to do with the Action Groups, to be quite honest. I usually have set keys for set functions (10 is always solar panels, 9 is always ladders, etc), but I didn't want to assign the groups for this craft according to my own conventions since I wasn't building it for myself. Do you (or anyone else) have a suggestion for a more intuitive order? For future reference of course, since voting has already started. When piloting VTOLs on Kerbin, I also find it much easier to simply "meet the ground running" as you put it. That's the major reason for me choosing wheeled landing gear over struts, though most of my other VTOL designs (those not suitable for this challenge) have both... for convenience and aesthetics.

Thanks for the kind review! For potential stock craft, those are (in my view) the most important factors. Thanks for the positive critique. Note that Action Group 1 toggles the torque on all three rearward Inline Advanced Stabilizers. Thanks for the compliments! I chose wheels over landing struts to allow pilots to land either vertically or horizontally. If the brakes are set before touchdown, they tend to act like landing struts anyway, so there's very little downside as I see it.

Well, it took several designs to find one I felt confident enough with to enter. For this challenge, I considered what the original stock craft might have been made to accomplish and what similarities should be kept. I decided that with most players quite familiar with the Rockomax 24-77, I could use this as an opportunity to showcase a different engine. I chose to highlight a useful application of the often-ignored Mark 55 radial engine. The craft, dubbed "Bullfrog," ended up with the same amount of fuel as the stock craft and a similar full-throttle flight range, but more thrust, making it noticeably more forgiving. Note: The above images were taken from three separate flights The craft file is available HERE. The following can also be found in the craft's description field: Action Group 1 toggles the trio of Inline Advanced Stabilizers, functioning as ballast and attitude control, Action Group 2 toggles the Telus Mobility Enhancer, and Action Group 3 extends the dual Communotron 16's. Additionally, the Abort action group shuts down the rockets and deploys the parachutes, making it fairly safe even at low altitudes. The craft is fun to fly and very responsive. Even with the three IASs disabled it turns smoothly, thanks in part to the gimbal range of the Mark 55 engines. Let me know if I've overlooked a detail or somehow missed a critical flaw.

I, like many others, have been playing around a bit with the new R.A.P.I.E.R. engine. Although it feels easier to use, it is definitely less effective than other, more traditional configurations. Still, it is fun to play with. This design, the Distesa, was a hopeful attempt at making a R.A.P.I.E.R. SSTO that could reach higher orbits(~600km) without the need for refueling. But given the performance limitations of the engine, I think it will be better suited to small crew transfers to stations at or below 200km. If I'm going to need to add more complexity to the design to make it work, I may as well use a configuration that's more effective to begin with. At any rate, here is the Distesa (SSTO-R 3):

Ah, that makes sense. Yes, on Kerbin it will definitely get stuck if you manage to flip it over. However, during my Duna test-run, it flipped over due to the twitchy nature of rover wheels and ended up on its head (without damaging any parts, either!). I was able to roll it back onto its wheels quite easily, so I'd suggest that turtling would only be a problem on the higher-gravity bodies. In a day or two (when I have Finals mostly squared away), I'll be spending some time looking through the other submissions and will post a summary of my initial findings and vote.

I'm glad you like it. The wheels were configured that way to prevent the rover from rolling over during sharp turns and from rolling forward during braking. What do you mean by "turtling"?

Here's my entry, the SCAR (Sky-Crane And Rover). According to Kerbal Engineer, the crane assembly has 736 m/s dv. More than enough for landings on atmospheric bodies, and theoretically enough to land on the Mun from a low orbit, though I haven't tried it myself. It can operate indefinitely in daylight, and for bursts of several minutes at night, thanks to its two RTG units. It is also equipped with all four science instruments and two Communotrons, all activated with Action Groups. Action Groups were created for the rover's equipment, and staging is set up for ease-of-use during flight. The "heat shield" is jettisoned and the drogue chute is deployed with the same staging event. And when it's time to separate the drogue chute, the dual Rockomax 24-77's are also activated. This way, you can focus on the landing instead of the staging. Here is the craft file for the SCAR. Orbital and transfer stages not included, though that craft file can be added on request. Feel free to post helpful criticism or any questions you might have.

Based on the results of this challenge I hosted a while back, the most efficient insertions were performed at low altitude. The challenge is quite old now (please don't necro it), but the principles still hold true. There's a lot of good information in there, so look through it if you're interested and hopefully it will help. Of course, this assumes that by "best" you mean "most efficient."

So I finally decided to try out intake spamming in order to make an SSTO with capabilities beyond LKO. I used the standard two-jet-one-rocket configuration with 10 Ram Intakes and two Radial Intakes per engine. I arrived on Minmus' surface with 50% of my fuel remaining, so I suspect the craft is capable of getting to orbit around Duna or Eve, though I doubt a return from either of them would be possible. All in all, I have to say that using so many intakes makes achieving orbit trivial and feel like less of an accomplishment, but it's pretty cool to take a single craft from the runway to somewhere other than an orbital station. Thanks for continuing to run this challenge, boolybooly! It's always fun.

That was my first thought as well, but even a stack of fuel tanks and an engine weren't enough. As I sank into the water, the parts just disappeared. And in that example, I splashed down at under 10 m/s, which is normally safe for just about anything. After that, I didn't do any extensive testing or anything, I just modified my approach and splashed down as slowly as I could manage with rocket assistance.

Parachutes and landing legs are great when you're landing on terrain, but my main problem is making sure the Science Jr pod survives splashdown. Anything more than 2-3 m/s and it's "Goodbye science!" At this point, I almost don't need parachutes at all, with all the practice I've had performing powered landings.

I enabled part clipping. With it, my craft has an initial 4:1 intake to engine ratio. Not terribly overdone as far as part-clipped airhogging goes, though I used Action Groups to deactivate two of the engines when the atmosphere became too thin to run all four. That left me with an 8:1 ratio, which is what really allowed me to achieve the 41km altitude.

Well, this was a fun design challenge. My entry is capable of delivering one NERVA from an operational ceiling of 41km at a speed of 2350 m/s. If my math is right, that's 130 pts. And no re-entry effects to give away the craft's position, either. I call it the HAS Bomber (High Altitude/Speed). Of course, this put me within range of their orbital defenses... apparently.

Funny you should mention that... People started talking about maneuverability and it occurred to me that mine might not be maneuverable enough. So, I'd like to replace my previous craft with the one I'm providing now. Sorry for any inconvenience Here's the T6e Peregrine, an improved-maneuverability trainer with plenty of power and service range. It even comes equipped with an ejection system for those really-hairy situations. Album can be found here.

Respawn: Congrats on another successful mission! Your entry has been added to the Scoreboard. Thanks for the video as well, it's always good to see how other players achieve their orbits. Epthelyn: Congrats to you as well! I added your best attempt to the Scoreboard, but let me know if you'd rather have your vanilla attempt displayed.

Respawn, a score of 0.00 still counts as a success in my book. If you reach the minimum orbit with no fuel left again, take some screenshots and I'll add you to the scoreboard.

This looks like a fun set of challenges. So here's my entry for the replacement trainer. Officially named Trainer Jet in the craft file (big surprise, right?), it's responsive without being twitchy, it takes off at roughly 40 m/s, has a very manageable glide slope even with a full fuel load (making it easy to land) and only requires a couple notches of trim to maintain level flight without SAS engaged. Here's the craft file. Enjoy!

The fuel margin is pretty tight, that's for sure. A careful combination of ascent path and throttle management is essential for success. Sounds like you're making progress though, so keep it up and you'll get there. And feel free to ask any questions if you find yourself hitting a wall.

It's good to see some activity here again. That is definitely the plan. I wanted to create a follow-up to this a couple weeks ago, but there was no mid-term lull this time around, so I haven't had the time to give this the attention it deserves. Finals are this coming week, though and then I'll have two weeks free, during which time there will be a follow-up with a low-TWR craft and possibly a re-make of this one now that I'm more familiar with the new mechanics. Although it will not include a requirement re-entry (as the focus here is on the efficiency of the ascent itself), perhaps a bonus category could be made for those who kept enough fuel in reserve to bring the pilot home. Congrats on completing the challenge! I'll bet that if you get your Ap low enough, you can make it into the Double-Digit Club. Now let's see if I can add your entry to the Scoreboard... Anyone know how to force the forum to make new paragraphs?

Congrats on the docking! Now, to repeat the feat a few times and you'll be set. The main reason I was going to post in this thread was to suggest that the core issue could be not knowing how to perform a transfer. In your original post, you said: That tells me that you may not know how to go from one orbit to another, which could explain why all the advice in this thread was of little help to you. If your orbital rendezvous was done the same way you get to the Mun (assuming you still do it that way), repeating the docking may prove quite difficult. So the key question is: Do you now know how to transfer from one orbit to another? OP resurrected it himself.

Congratulations on completing the challenge! The score is 4.07, though since I didn't institute a new scoring system with the update to 0.21. Once mid-terms are over (tomorrow!) and I can take a breather, there will be a new challenge with a new craft and method of scoring, so keep an eye out for that.

Ideally, yes. However in practice, the turn will almost always require some steering corrections (unless you plan the turn and your rocket perfectly or get really lucky). Using gimballed engines helps give your craft control authority, but does not negate the benefits of performing a gravity turn. If you were to burn directly vertical until the craft is beyond the atmosphere and then turn it horizontal and add velocity, you would see huge fuel losses fighting gravity the whole way up instead of allowing it to bend your path and add horizontal velocity for you. Some of the vertical velocity will be converted by the gravity turn and some won't. The velocity that isn't will become what we refer to as "gravity losses." They can be minimized, but never eliminated entirely. Don't ask me about the math, I'm not that proficient yet.

For my 0.21 submission, I decided to try for a two-Kerbal spaceplane. Through good use of the cubic strut, I was able to get an extra RAM intake per engine, allowing for a very comfortable fuel margin. The first SSTO 4, designated "Resparcia" reached a 100 x 100km orbit with enough fuel for rendezvous and de-orbit without the need for refueling. Pre-launch in the VAB: In orbit, just before performing the de-orbit burn, with Mun and Minmus visible in the background: Re-entry successful, and on a good glide path to KSC. I would need to re-fire the jets to close the final 7 or so km and give me good control over the landing, but she handled very well under the light fuel load. And after a textbook landing, the Resparcia quickly comes to rest. The crew appear happy to be back on Kerbin unscathed. Always a fun time with the K-Prize!