Okay, so I've caved in and tried to make something with KAS (as I usually fly stock).
It left me with some... mixed impressions, due to some issues I'll try to find solutions to.
First experiment was, uncreatively enough, a space tug.
A trained eye may spot some glaring errors from the get-go, but I'll describe my experience with it in detail. Or try to.
The first launch went well, the carrier rocket (a somewhat unconventionally slim asparagus) having a TWR just at/around 2.00 at launch. Boosting into the skies, the asparagus shell exhausts itself just as it's time to do the gravity turn, and everything seems fine... until slightly too-strong wiggle of the controls shears the pusher stage off the center tank, leaving it locked in place but without any sort of control over the main engine. A typical KSP "oh crap" moment. The pilot, Bill, is rather distressed.
After some attempts to steer the resulting contraption, I decide it's better to abort the whole thing and get back to the ground. Decoupling the pusher stage does nothing - it's already broken off, and the extra force does not overcome the thrust of the main engine, which is at this point gradually turning northward and groundward.
Firing the pusher stage, though, detonates
everything below the tug's engines, including the winch array. Welp. At least the landing legs are intact. Adjusting the trajectory a little with the tug's engines so that it ends on land rather than in the water, I try to orient the craft "bottom down" to prepare for deceleration and landing.
At this point I notice two things. Firstly, the craft is aerodynamically inclined to always point "nose forward". It takes some doing, firing RCS to help the pod's reaction wheel, but eventually the tug is flipped nose up and legs are extended.
Secondly, I forgot to add parachutes. >_>
Thankfully, the tug has a TWR of >1, so it manages a powered landing... in pieces, after hitting a sudden incline. No lights either. *sigh* Well, any landing you can walk away from... Bill seems okay with it at least.
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The craft is returned to the launchpad post haste. The ascent is perfect this time, and the pusher stage dies just short of proper orbit, allowing the tug to circularize by itself and leaving no extra debris in space. The target is set: an old piece of debris, a small rocket used to deliver an RCS shuttlebike to the refueling station. It still has some fuel, and it has a command pod too, but since deorbiting it with a pilot on board would be bad (it has no means to even decouple the pod), this tug is a perfect way to get it back to the ground.
The approach is fairly uneventful, Bill easily syncs up the tug's orbit with the piece of debris, and soon enough the two are right next to each other, even despite a momentary delay as I realize that the tug has no lateral RCS - it can translate sideways, up, down, but not forward or back. Welp. But no matter. Everything else on this flight went right so far.
Commencing first test of the winch system. I haven't so much as read the readme on the thing, so Bill is going in blind. The tug has four winches, all aimed sideways, each equipped with a connector and a detachable connector port. In addition, four electro-magnets are stored in bays on the secondary pod of the tug - just in case the detachable ports don't work.
Just in case.
The first attempt to retrieve a connector port ends with the thing drifting off into space, further attempts to pick it up unsuccessful.
The second attempt succeeds, although it takes several tries of different actions before the port is safely stored on Bill's backpack, and the connector itself is left floating next to the tug, the winch cable trailing behind it. So far so good.
However, no attempt to actually place the supposedly attachable radial connector port ever succeeds. Even putting it back onto the tug fails, an attempt born of suspicion that craft made prior to installation of KAS are somehow immune to the function.
The second radial connector port floats off into the void...
Obviously, at this point the "just in case" option becomes the primary one. Bill retrieves a magnet, and successfully attaches it to the floating connector. Then, after some fumbling, picks the magnet up together with the cable, and deposits it near the disused rocket. Success! All that's left is to get back into the tug and... why is it floating away?
A momentary check of the surroundings reveals that while Bill fumbled with the winches, the tug, at a snail's pace of 10 centimeters per second, had gradually crept away from the target rocket, and had picked just that moment to drift beyond the winch cable's maximum 50-meter range. Crap.
Well, nothing bad happened yet. Only time lost. Bill gets back into the tug, takes a moment to look at the winch controls (for the first time since launch), and reels the floating magnet back in. A minute or drifting around later (without lateral RCS), and the tug is back in position. Bill gets out again, and goes to pick up the magnet to deposit it near the rocket. After picking the magnet up, Bill hits the winch control button for "extend", allowing the cable to build slack, and flies off towards the rocket. Some seconds after he approaches it, an ominous shadow gives him mere moments to react as the tug, pulled by the cable, smashes into the rocket, sending it spinning.
Apparently Bill accidentally pressed the button for "retract".
Welp.
No damage done yet again, but even more time is lost. Not like there's a time limit, but still.
Bill gets back into the rocket as the cable retracts and the magnet is locked in place. It takes another minute or two to catch up to the now-spinning piece of debris. The spinning makes it dangerous to approach, but at the same time it's a perfect excuse to test another of the winch's functions - "Eject". The magnet being a magnet, it should ideally be able to attach easily enough even to a spinning object. After a quick initial test of the system - the magnet flies off, rebounds back on the elastic cable, and clamps onto the tug's hull - everything is ready. The tug is in position, the target is in sight, all that's needed is to aim... oh right, all winches face sideways. Welp.
No matter. For a seasoned veteran such as Bill, this is peanuts. Some fiddling around with controls later (no lateral RCS...), and the first shot with the magnetic projectile hits home, a dull 'clang' announcing, even through the vacuum of space, that the mission is a success. The tug accelerates slowly in retrograde, finally pulling the disused piece of rocketry out of its orbit. With only one cable attached and the rocket still spinning, the tug is being pulled all over the place, but the SAS system holds fast - the course is (roughly) held. It seems that, after all the trouble with the system, everything might finally work out.
Suddenly, the magnet clamps off from the rocket. Bill checks for damage - nothing. Did it just get torn off, due to the stress? Maybe. The rocket's orbit wasn't altered enough yet, so the tug turns around and flies back, reeling its magnet in to try a second time. Bill wants to take no chances a second time, so after parking the tug, he goes out and attaches another magnet - to the winch opposite the first one, which is coincidentally the same one the first connector port was lost from. Two magnets should hold better than one.
Back in the tug, Bill aims the winch to fire... and hits a snag. Now there are two winches with magnets on them, and he can't remember which one he's aiming. He hits one at random. A connector shoots out to the side. Whoops, wrong button. He hits one of the "Magnet" winches. The opposite one ejects its magnet. Welp. Only one left... *click* *clang*. Yes!
With one magnet attached, the other two winches reel in. And suddenly stop. Bill pushes the button again. It stops again. And the magnet has disengaged too. What the...
It takes some time to figure out the problem, which is partially caused by the huge GUI window of the KAS system. Or at least it was hidden by it. Hiding behind the KAS window was the resource readout, and a big yellow sign reading "Winch operation stopped: No power". From there, the final design error reveals itself.
Back when the tug was being designed, the magnets were put on as a spur-of-the-moment decision. "Just in case", should the radial connector ports not work. The bays that hold the
electric magnets occupy the same places on the hull where the main solar arrays of the tug were supposed to be, and were later forgotten to be placed. The two flat "emergency" panels on the craft supplied it enough power to work the winches and reaction wheels while it was on the day side of Kerbin, and the eight battery packs provided enough of a power supply that the problem didn't become immediately apparent. As such, having spent too much time in space and drifting towards Kerbin's night side, the tug had completely run out of power, with only occasional trickles fed in by the last of the Sun's rays.
Seeing no other options, Bill declares the mission failed. The tug spends a moment to recharge a little and reel in the floating connectors, then points itself retrograde and deorbits.
The deorbit trajectory takes the tug well into Kerbin's night side. With no power to work the reaction wheels, and the short profile of the craft giving the RCS and the LV-909 thrust-vectored engines too little control authority in the atmosphere, the tug cannot tumble over to decelerate.
The parachute... um. What parachute? >_>
The R&D division had dutifully collected all the data from the ship's black box (which they had to extract from under fifty meters of desert sand), and by the time Bill emerges from his hospital bed/cloning tube, they will have a much renewed and improved model of the space tug ready for him to pilot. That rocket won't deorbit itself. ^_^
...
Also, belated wall of text warning.
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Topic: Kerbal Space Program: Now Hiring Optimistic Astronauts for Dangerous Munission (Read 1505469 times)