Kerbin Circumnavigation Challenge - Reloaded [New Rules Once More]

[Torham234]

Do I still qualify with my old entry?

[Flixxbeatz]

Do I still qualify with my old entry?

-snip-

Well since I've accepted an earlier entry with Kerbal Alarm Clock on by accident, I might as well accept it still. Welcome to the club once more

[Kuris]

Im participating in yet another Challenge. Here's my entry. Hardest part was to keep the plane in right altitude. I almost could smell the 25 km altitude...

[Torham234]

Well since I've accepted an earlier entry with Kerbal Alarm Clock on by accident, I might as well accept it still. Welcome to the club once more

I simply failed to remove the alarm clock plugin before doing the challenge. I have not even touched it (and I cant see any way how it would have aided my attempt ), I promise

I was just thinking. If you went in the opposite direction to the rotation of the Kerbin, wouldn't you have to travel shorter distance ( since the KSC would be travelling to meet you, rather that moving away from you).

If you do the challenge at 90° you need to do around 3900 km. the equator of Kerbin is 3770 km, so travelling towards 270° heading, you would only need to do around 3640 km (depending on your average speed)...

[Teirusu]

Here's my rather simple jet,

Take off..

Sun rise...

Mun rise...

Sun rise again over final KSP approach...

Landed!

Results! Only realized after this that the back of the tail cone holding the ram intake on the bottom was slightly sticking out of the engine! But, its still in one piece! Heh

And here's an earlier attempt where I had forgotten that I had the SIP mod installed. (Stock Improvement Parts) Only needed 1 tank of fuel then, with fuel to spare! Obviously this doesn't count, but I thought I'd mention it.

[PolecatEZ]

This actually took two attempts.

On the first one, 50km from the finish line, my aircraft freaked out when I took off the SAS to do the descent into the airport. It flipped nose up, and went to 25,025m before I got it back under control. Argh.

One quick re-design:

Here's a screenie from the first attempt...Seedorf isn't so jaded yet. I chose to go west instead of east. To be honest, I didn't feel a real difference. What was different is using 4x compression after building a more solid craft.

And a successful finish. Missed the runway by about 1km or so because I was way too light to land, the plane could probably glide the globe if given enough time.

[Flixxbeatz]

-snip-

That is one of the actual challenges here, trying to keep the aircraft in the right altitude set by the rules. Well done!

-snip-

I can't actually believe that you've done it on a craft as small as that welcome to the club!

-snip-

A few more wings probably, and it could probably glide kerbin from end to end congratulations!

I was just thinking. If you went in the opposite direction to the rotation of the Kerbin, wouldn't you have to travel shorter distance ( since the KSC would be travelling to meet you, rather that moving away from you).

If you do the challenge at 90° you need to do around 3900 km. the equator of Kerbin is 3770 km, so travelling towards 270° heading, you would only need to do around 3640 km (depending on your average speed)...

Sounds feasible, since winds aren't implemented yet and you have nothing to go against, as far as I know. Haven't tried it myself, though...

[tavert]

I was just thinking. If you went in the opposite direction to the rotation of the Kerbin, wouldn't you have to travel shorter distance ( since the KSC would be travelling to meet you, rather that moving away from you).

If you do the challenge at 90° you need to do around 3900 km. the equator of Kerbin is 3770 km, so travelling towards 270° heading, you would only need to do around 3640 km (depending on your average speed)...

The atmosphere moves with the surface, and since Kerbin is spherical you always have to cover the same great-circle surface distance no matter which direction you choose. Going polar makes it a bit tricky to be sure you come back over KSC, but comparing 90 vs 270 there's no difference in distance. The difference is whether Kerbin's rotation adds to or subtracts from your surface speed: going east orbital speed is faster than surface speed, going west orbital < surface. I haven't tried this with a 25 km ceiling (I was doing the other one with a 45 km ceiling and allowing MechJeb), but judging by the max speeds in the results here so far, you guys haven't been getting quite to orbital speeds since there's too much drag at 25 km. Since you're below orbital speeds, it's better to go east so you don't have to fight gravity as much - your orbital velocity will be higher for the same surface velocity (which is determined by thrust vs drag, and possibly intake air if you can't sustain full throttle) so your periapsis won't be as far below the surface, your suborbital trajectory will be less curved and the effective acceleration due to gravity will be lower.

[Torham234]

The atmosphere moves with the surface, and since Kerbin is spherical you always have to cover the same great-circle surface distance no matter which direction you choose. Going polar makes it a bit tricky to be sure you come back over KSC, but comparing 90 vs 270 there's no difference in distance. The difference is whether Kerbin's rotation adds to or subtracts from your surface speed: going east orbital speed is faster than surface speed, going west orbital < surface. I haven't tried this with a 25 km ceiling (I was doing the other one with a 45 km ceiling and allowing MechJeb), but judging by the max speeds in the results here so far, you guys haven't been getting quite to orbital speeds since there's too much drag at 25 km. Since you're below orbital speeds, it's better to go east so you don't have to fight gravity as much - your orbital velocity will be higher for the same surface velocity (which is determined by thrust vs drag, and possibly intake air if you can't sustain full throttle) so your periapsis won't be as far below the surface, your suborbital trajectory will be less curved and the effective acceleration due to gravity will be lower.

The idea was that you would not need to complete a full circle, because by the time you were approaching KSC, it would have closed the gap by some. It should work, since we always need to travel more that the kerbin equator, because the KSC keeps moving away from you. ( around 170 km per hour, by my calculations). That would give you roughly 340 Km extra free distance per 1 hour of flight time. Since the challenge is to land at KSC after going around the planet, that would still qualify, but you would be travelling physically shorter distance.

I did do some tests this afternoon, and I was getting higher surface speeds going 270°. The snag would be that you said the atmosphere moves with Kerbin surface, that would mean any advantage gained from going counter rotation would be obliterated by the increased drag ( although if that was the case, I shouldn't have observed increased surface speed going 270°).

But I think this point is moot by now, since Teirusu managed to do the trip on less than 300 fuel. ( witch is what I was trying to do).

[tavert]

The idea was that you would not need to complete a full circle, because by the time you were approaching KSC, it would have closed the gap by some. It should work, since we always need to travel more that the kerbin equator, because the KSC keeps moving away from you. ( around 170 km per hour, by my calculations). That would give you roughly 340 Km extra free distance per 1 hour of flight time. Since the challenge is to land at KSC after going around the planet, that would still qualify, but you would be travelling physically shorter distance.

I did do some tests this afternoon, and I was getting higher surface speeds going 270°. The snag would be that you said the atmosphere moves with Kerbin surface, that would mean any advantage gained from going counter rotation would be obliterated by the increased drag ( although if that was the case, I shouldn't have observed increased surface speed going 270°).

But I think this point is moot by now, since Teirusu managed to do the trip on less than 300 fuel. ( witch is what I was trying to do).

I think you misunderstand my point. KSC does not move relative to the atmosphere. The rotation of Kerbin only makes a difference to orbital speeds, not surface speeds. When you fly a plane low and slow enough that you aren't approaching an orbit, thrust lift and drag determine your flight characteristics almost entirely, heading has a minor secondary effect only in the effective force of gravity (and if you aren't staying along the equator, then heading will drift due to Kerbin's rotation and your orbital inclination). Thrust, lift, and drag only depend on surface velocity.

I'm somewhat surprised at you getting higher surface speeds going west, if you were still under 25 km. It is definitely true at higher altitudes and speeds that you can go faster to the west before reaching orbital speeds and gaining altitude out of the atmosphere, but nobody here has been going fast enough for that to be an issue yet.

Edited May 24, 2013 by tavert

[Torham234]

Yes, it seems you are entirely right. I have just done 2 test flights with my experimental glider. This time I used the lazor flight autopilot to minimize piloting and steering error.

1: heading - 90°

fuel : 150

cruise altitude - 24.500 km

Surface speed - 1123 m/s

distance traveled - 2990 km

Ground distance traveled - 2982 km

2: heading - 270°

fuel: 150

cruise altitude - 24.500 km

Surface speed - 1127 m/s

distance traveled - 2965 km

Ground distance traveled - 2958 km

[Torham234]

AHA!!!

Fuel used : 216 units...

The main problem now is that the aircraft is becoming too short to be maneuverable. I could use some lightweight girders, but that would introduce some extra weight.

I do not have the starting screen because this was originally just a test run, but the design outperformed the expectations and so I took it for the whole trip...

just after I used half the fuel

And landed. I had fuel to spare to attempt an air strip landing, but by this stage I was too nervous to do any dangerous maneuvers, lest I crash. I just plonked it near the KSC on the grass...

[XVeris]

Finally got a plane off the run way in one piece, AND it flies pretty well, but...my pilot is stupid...

Will post my completion of the challenge in a few days, still got a few school assignments left to do

Edited May 24, 2013 by XVeris

[Flixxbeatz]

Finally got a plane off the run way in one piece, AND it flies pretty well, but...my pilot is stupid...

-snip-

Will post my completion of the challenge in a few days, still got a few school assignments left to do

That UI looks neat. Is that a plugin? Or just me not checking out 0.20 yet...

[XVeris]

That UI looks neat. Is that a plugin? Or just me not checking out 0.20 yet...

It's you not checking out 0.20 yet, xD. On the System Map ("M", that map thing), they added two info buttons on the right side. Of the object you're focused on, they tell different info, such as pilots, speed, and so on. If it's a planet you're focused on, it'll tell you a bit of back history to the discovery of that celestial body, as well as some statistics about it. Pretty neat, to say the least.

[Teirusu]

So, after some thought.. I decided to try something. I stripped my jet down to the bare essentials... I think I won. Thing doesn't look all that great anymore though xD

And the results from the orbital so you can see the tonnage at the end!

[Torham234]

My god. So that design is actually feasible. I did have some builds very similar to that one, but I couldn't quite stretch the fuel far enough. Best I could do was nearly 3000 km on 150 fuel.

[Kolt]

I simply had to try this! Awesome challenge and a lot of fun if you use avionics package

Had to turn off the engine so that I wouldn't over shoot it and so that I could align myself with the runway.

I do have to say, and you can see it on the top left corner, I have crew manifest installed. Doesn't really help the craft (that I'm aware of) and in the end I didn't even use it since Bill was on one of my space stations and I was to lazy to bring him down

[Flixxbeatz]

I simply had to try this! Awesome challenge and a lot of fun if you use avionics package

-snip-

I do have to say, and you can see it on the top left corner, I have crew manifest installed. Doesn't really help the craft (that I'm aware of) and in the end I didn't even use it since Bill was on one of my space stations and I was to lazy to bring him down

Much like the "Kerbal Alarm Clock" case, I'll be letting this one pass. Congratulations!

[BlueFox801]

Well, after multiple frustrating attempts (most of which failed due to pilot error) here's my my entry. I know it's not the flashiest plane, but it got the Kerbal all the way around Kerbin.

[Flixxbeatz]

Well, after multiple frustrating attempts (most of which failed due to pilot error) here's my my entry. I know it's not the flashiest plane, but it got the Kerbal all the way around Kerbin.

-snip-

Everyone's been there. Trying and trying until making it successfully congratulations!

[blackcap76]

OK, here is my attempt. I almost had a runway landing but I came in too fast and had to do some serious breaking at the end to avoid the water. But I made it!

Edited May 26, 2013 by blackcap76

[Torham234]

OK, here is my attempt. I almost had a runway landing but I came in too fast and had to do some serious breaking at the end to avoid the water. But I made it!

That plane looks very elegant.

[Flixxbeatz]

OK, here is my attempt. I almost had a runway landing but I came in too fast and had to do some serious breaking at the end to avoid the water. But I made it!

-snip-

That thing looks like it would snap into half anytime in-flight, if not for the struts good job!

[Wyseman76]

This was my second attempt with a completely new plane design. I hope you can let the crew manifest mod slide as my five year old son loves to rename my kerbal crew members, which is all it does.

First off it was a wild ride and I wasted a bit of fuel trying to establish a balancing point between speed / alt / and fuel efficiency but I managed by the skin of my teeth.

So one with the show.

12 mins I'm burning away from KSP with high hopes

19 mins MUN in sight. Holy crap i'm wasting fuel!

28 mins Ok i think I can still make this...??? Nice sun set.

55 mins Damn, I don't think I'm going to make this, well at least I can see the sun again.

1 hour Fuels still tight, should I keep going.... Nice scenery.. Yup I'm still going for it!

1 hour 23 mins I can see the center fuel is critical but I have a great glide slope if I can just stay focused. Damn I got to pee.

1 hour 28 mins glide slope is still solid and she is handling great as the speed drops. I got this.

1 hour 29 mins On the runway safe and sound. Holy crap I was on fumes.

Final stats. What a great ride, a real close one.

Thanks for the Challenge it was a blast, now I'm going to pass out.