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[Karlito]

Didn't we do a test earlier on and found that the concept of "wasting fuel to air resistance" wasn't actually a thing, and it was in fact best to gun it as fast as possible?

Take a Mainsail and a single standard 3m tank, under a Mk3 capsule. Max throttle up and see how far you go. (my experiment: 28Km) Then take the same setup and swap the mainsail for the closest thing mass and Isp-wise - six of the Mark55 surface-mounted engines - throttle up and see how far it goes. (my experiment - 58Km) See the difference.

Or for a more concise demonstration, repeat the launch of the mainsail rocket but keep the throttle at 50% the whole time (the end result is the same).

[sluissa]

Didn't we do a test earlier on and found that the concept of "wasting fuel to air resistance" wasn't actually a thing, and it was in fact best to gun it as fast as possible?

Take a Mainsail and a single standard 3m tank, under a Mk3 capsule. Max throttle up and see how far you go. (my experiment: 28Km) Then take the same setup and swap the mainsail for the closest thing mass and Isp-wise - six of the Mark55 surface-mounted engines - throttle up and see how far it goes. (my experiment - 58Km) See the difference.

Or for a more concise demonstration, repeat the launch of the mainsail rocket but keep the throttle at 50% the whole time (the end result is the same).

Confirmed. 3 person pod, single full sized grey tank, mainsail engine. Full throttle got to 28km. Half throttle got to 64 km. Full throttle is not the best way to go.

Scaled it up as well, but is less of a confirmation as I had to fiddle with the throttle on the full run to keep it from overheating, but with an orange tank. Full throttle(down to about 4/5ths to avoid boom) got to 275kmish. Half throttle(down to about 2/5ths to stay at half of the full run) 325km.

Full throttle is not the way to go until you're out of the thick part of the atmosphere.

[peskyninja]

In that screen I was using cheatjeb so it was full throttle (I was eating). But in my experience is much better to go full throtle on the first few meters, wait till you wasted some fuel and the rocket is ligther then start to lower the throtle to maintain a desired speed then only after you exited 3/4 of the atmos you can go full throttle. (This is for increasing AP, if you go into orbit withou tfull throttle you will have an AP of 120km or so)That design I've posted earlier seems to be pretty efficient if used in the correct way, you could remove some engines but I have no patience to crawl into space.

Ask me question now because I'm going to travel to the countryside tomorrow morning.

[alway]

Or to repeat the conclusion we came to earlier (after all, we had like 10 pages of discussion on the issue), it depends on the weight and such of the craft. For a dense craft, gravity is more a concern than air resistance due to the inherently low upwards acceleration (as the extra weight makes it the equivalent of being at partial throttle on a smaller craft). Light and medium craft (in this case, medium meaning about the size of that in the previous image) should start at lower thrust; heavy and super-heavy craft should pretty much go full blast (and in most cases, can't even get off the ground with anything less).

[peskyninja]

Or to repeat the conclusion we came to earlier (after all, we had like 10 pages of discussion on the issue), it depends on the weight and such of the craft. For a dense craft, gravity is more a concern than air resistance due to the inherently low upwards acceleration (as the extra weight makes it the equivalent of being at partial throttle on a smaller craft). Light and medium craft (in this case, medium meaning about the size of that in the previous image) should start at lower thrust; heavy and super-heavy craft should pretty much go full blast (and in most cases, can't even get off the ground with anything less).

Checking my ascent details in mechcheat, I've noticed that my air resistance losses are 6%(?)(I am surprised too.)

[ank]

You never want to start out at low thrust:

You want to full burn up to some point (We figure it's a bit above 200m/s)
then throttle down(still gaining speed) to some undetermined point, and slowly throttle up.

Many vehicles can burn at full thrust all the way, depending on the thrust/weight ration, so this might not apply to your craft.

to the new guys, go read wikipedia on gravity drag, and you will see why.

[peskyninja]

Spoiler: Wobbly station is wobblying. (click to show/hide)

It is MOBILE!

Spoiler: Lazy munar colony (click to show/hide)

Launch

Before landing

Landed, a bit chilly, 0.02 C. I'm planing to expand and add some carts.(It has a docking port on top of it)[For the record I can land without mechcheat, I'm just too lazy today.] Expect some more elaborate creations the day after tomorrow as I'll spend 4 hours on a car.

Spoiler: Minmus probe (click to show/hide)

Landing


Landed, it seems that minmus soil has some sort of ligth generating capabilities as the solar panel can absorb energy from it.
And I've also discovered that if you don't mind wasting some fuel and time it is much much much easier docking stuff and making large stations on minmus or mun orbit.

And that's all folks. I'm off to bed. Tomorrow will be a long day.

[Roboboy33]

While flying to the crater site I saw some specks in the desert...
And found this.

Spoiler (click to show/hide)

A higher view.

Spoiler (click to show/hide)

Two large pyramids with some walls halfway around them with four smaller ones at the corners of the biggest one.

A quick test confirms they are solid.

Spoiler (click to show/hide)

And then... woah.

Spoiler (click to show/hide)

Another angle

Spoiler (click to show/hide)

[Sirus]

While flying to the crater site I saw some specks in the desert...
And found this.

Spoiler (click to show/hide)

A higher view.

Spoiler (click to show/hide)

Two large pyramids with some walls halfway around them with four smaller ones at the corners of the biggest one.

A quick test confirms they are solid.

Spoiler (click to show/hide)

And then... woah.

Spoiler (click to show/hide)

Another angle

Spoiler (click to show/hide)

Whoa, is this on Kerbin?

[Roboboy33]

Yes, it's in the desrert.
6o 31' 48" S
141o 41' 3" W

[Aseaheru]

gasp. is there a city on the world yet?

[alway]

You never want to start out at low thrust:

You want to full burn up to some point (We figure it's a bit above 200m/s)
then throttle down(still gaining speed) to some undetermined point, and slowly throttle up.

Many vehicles can burn at full thrust all the way, depending on the thrust/weight ration, so this might not apply to your craft.

to the new guys, go read wikipedia on gravity drag, and you will see why.

Actually, we have those science sensors now! They tell atmospheric pressure, g forces, and the force of gravity. I suspect with some decent calculus, we might actually get to the bottom of the exact numbers. In any case, vaccuum appears to start at ~45km; so anything above there should always be as full thrust as is practical.
As for atmospheric pressure, it appears to be about 50% the starting pressure at around 3500m, droping to 33% at around 5500m, 20% at 8000m, 10% at 11000m, 5% at 15000m, 1% at 23000, 0.1% at 35000.

The air resistance should be proportional to the density of the air. That density is generally hard to calculate, and as such, I will assume KSP has a simple system where the two are effectively one and the same (if they simulate air temperature in the atmosphere somehow, this is a false assumption; but I'm pretty sure they don't actually do that). Which in turn means that, ignoring staging, air resistance force is relative to those values above. The other thing of note in the drag formula is that it uses velocity squared. Doubling velocity quadruples air resistance. Though doubling velocity also causes air density to drop off at the measured rates much more quickly, as well as reducing the delta v lost to gravity. So it's mostly a matter of balancing a few integrals. !!SCIENCE!!

[ank]

well, you'd have to figure out a function for air drag, then find where the graph crosses the graph for gravity drag.
I'm guessing it's something along the lines of F=drag*speed^2.
Problem is that it's likely measured in Newtons per meter, and the function for gravity gives Newtons per second, right?
I'm sure there's a way to convert, it just escapes me right now.

One thing that is on our side is that pretty much all parts have the same weight/drag ration, which means that the rules will be the same for all ships, no matter how big or how small, the only important thing is the weight/thrust ration.

As far as I recall the function for gravity drag is just gravity acceleration: F=g*m , so the net thrust would be Thrust-(g*m). so we plot thrust as x and net thrust as y, which should give us a linear function.

And....... now I'm stuck.... need to think more about it.

[LoSboccacc]

I present you the leviathan, the last iteration of my unimaginative rockets to attach big engines and fuel to different things that may need it.

Spoiler (click to show/hide)

It can easily get into 100 to 150km orbits, and after that it still have plenty of fuel for further maneuvering. here is the final maneuvering form:

Spoiler (click to show/hide)

Based on previous iterations and experiences, I split the maneuvering fuel from the payload fuel. Also, after some Jools exploration experiences, I added some lateral docking ports, so another leviathan can come and refuel it for extremely long missions (actually works best using two leviathans attached so when they arrive one is still full).

the capsule has some fuel for reentry from a low orbit, but you will need other means to bring the guy back from an extended refueling mission...

[Spaghetti7]

WARNING: Large Images

Finally managed to ship my little green men off to another planet! Got in a nice orbit with Duna, which involved a close encounter with Ike:

Spoiler (click to show/hide)

Cooeeee:

Spoiler (click to show/hide)

Said encounter:

Spoiler (click to show/hide)

And even managed to set her down without ripping anything off with the parachutes.

Spoiler (click to show/hide)

I'm loving the new version. Maneuvers help a lot.