How to preform orbital insertion????

[John Doe]

Anyone have any idea how to raise paraphasis enough  to get into orbit from a suborbital flight path using the stock Kerbal 5? I've tried thrusting prograde upon reaching the apogee (Apostasis) in order to attempt to raise the periphasis high enough to constitute an orbit, but either I always seem to run out of fuel before the periphasis raises enough, despite adding an extra fuel tank to the engine and then proceeding with attaching  the stack decoupler to the tri-coupler. (and even thin this added tank likes to explode on me half the time at around 8,000 meters or so into the launch.

[Plusck]

I'm not sure which ship you're talking about.

The only stock craft with a 5 in it in my install (1.1) is the Kerbal 1-5, but there is no tri-coupler on it. The Kerbal 1-5 can get to orbit with about 37-40 fuel left, according to my attempts. It's quite forgiving for the gravity turn as long as you don't overdo it and drop too low too soon.

Or is this in one of the new tutorials?

[Rhomphaia]

 

2 hours ago, Plusck said:

I'm not sure which ship you're talking about.

The only stock craft with a 5 in it in my install (1.1) is the Kerbal 1-5, but there is no tri-coupler on it. The Kerbal 1-5 can get to orbit with about 37-40 fuel left, according to my attempts. It's quite forgiving for the gravity turn as long as you don't overdo it and drop too low too soon.

Or is this in one of the new tutorials?

The Kerbal 5 used to be in an old version of the demo, sometime pre 1.0.  It is not any more,  Seem to remember it could get to Mun orbit.

[John Doe]

By the Kerbal 5... This screenshot is what I mean... http://tinypic.com/r/wiu8p1/9

Edited April 23, 2016 by John Doe
malfunction- need to include screenshot

[Harry Rhodan]

8 hours ago, John Doe said:

paraphasis

(Apostasis)

Periapsis and Apoapsis.

 

Don't know where you got the old demo but the old paradigm of getting to orbit was basically going straight up  to 10km, then turning 45° and trying to keep your time to apoapsis in the map view somewhere between a minute or a half.

If you get the newer demo where there's actually an aerodynamic system you want to begin turning slowly and gently shortly after the launch.

[John Doe]

Well, I have managed to do it- to successfully launch to an orbit just a bit higher than a LEO, and pull of a successful re-entry manurer.  Interesting thing was when I decoupled the command capsule from the last fuel tank / rocket (which I executed immediately upon doing an exahustive antegrade burn) I managed to inadvertently insert the fuel tank / engine assembly into a satellite orbit.

[Plusck]

18 hours ago, Rhomphaia said:

 

The Kerbal 5 used to be in an old version of the demo, sometime pre 1.0.  It is not any more,  Seem to remember it could get to Mun orbit.

Wow, completely forgot about that. I just went back to it and it was a very weird experience. I have it in a demo dating from February 2013, version 0.18.3.

The atmosphere is particularly odd, now I've got used to the newer versions.

To get the Kerbal 5 into orbit, the simplest approach seems to be to head up at 75° until you get an Ap of about 100km, then head 45° or so until you have an Ap of 250km, then coast and circularize

Even the old paradigm of heading 45° at 10km doesn't work that well - you're better off going much higher before trying to slurp through the atmosphere.

Edited April 23, 2016 by Plusck

[John Doe]

Actually the way I pulled it off was to stay near vertical up until 10,000  and then adjusting to around 50 to give me a wider initial suborbital path, with apogee about two and a half to three minutes away, and then of course raising the apogee to around  227,369. This renders the periapsis at around 124,827, a fairly circular orbit. Problem is that this leaves me with barely enough fuel to lower the periapsis enough for re-entry, after all is said and done. I've tried adding an extra stage with a simple fuel/engine combo, and the necessary aerodynamic components, but this will either end up exploding on me in true Apollo 1 style (though occasionally it will go challenger style at around 1:30 seconds or so into the mission) but even when I manage to get ready to manurer to my prograde vector, I find that it likes to swing back and forth like a chimp on a rope, and that's with heavy use of sass in attempt to stabilize, so by the time I manage to get my prograde worked out, I'm already so far into the decent that firing prograde does nothing but expend fuel to engine cut off.   And I'm running the demo version through the Linux Steam application. (which apparently wasn't updated.)

[Mahnarch]

On 4/23/2016 at 4:31 AM, Harry Rhodan said:

Periapsis and Apoapsis.

Parachutes and Applesauce.

 

Only one of those makes sense in context, but it's easier for my brain case to pronounce.

[John Doe]

Actually the term Apogee (Pronounced A' Poe' Gee) is synonymous with Apoapsis, and the term Perigee (Pronounced Peri'Gee) is synonoymous with Periapsis. The difference between the two terms is that Apogee /Perigee became the less formal, but more commonly used terms, particularly during the Apollo and STS missions. The latter terms are the more formal terms found in the study of astrophysics within the classroom context. The fact that the game elects to use the more formal terms is unusual given the context of manned flight missions.  

[Superfluous J]

3 hours ago, John Doe said:

Actually the term Apogee (Pronounced A' Poe' Gee) is synonymous with Apoapsis, and the term Perigee (Pronounced Peri'Gee) is synonoymous with Periapsis. The difference between the two terms is that Apogee /Perigee became the less formal, but more commonly used terms, particularly during the Apollo and STS missions. The latter terms are the more formal terms found in the study of astrophysics within the classroom context. The fact that the game elects to use the more formal terms is unusual given the context of manned flight missions.  

I'm sorry but this is not true. the "gee" in "Apogee" means "Earth" (Because reasons). Similarly, you can speak of "Perilune" for the lowest point in your Moon orbit.

the "apsis" in "Periapsis" is relating to the apsis of your elliptical orbit. There are 2 in each ellipse, and the planet or moon or star you are orbiting is one of those two apsides. THAT apsis is what we are peri- or apo- from in our orbit.

I was wrong above. I'm glad I checked it

The "apsis" in "periapsis" comes from the same Greek word, for the top of a curved archway. In an ellipse, there are two such pointed curved areas, at the "ends" of the ellipse. The end of the ellipse that is closest to the planet is the periapsis, and the furthest one is the apoapsis.

Around Earth, they mean the same thing as perigee and apogee, but they those two won't be correct if used around the Moon, or Mars. The more general terms are correct everywhere.

Edited April 25, 2016 by 5thHorseman
Latin is all Greek to me!

[John Doe]

2 minutes ago, 5thHorseman said:

I'm sorry but this is not true. the "gee" in "Apogee" means "Earth" (Because reasons). Similarly, you can speak of "Perilune" for the lowest point in your Moon orbit.

the "apsis" in "Periapsis" is relating to the apsis of your elliptical orbit. There are 2 in each ellipse, and the planet or moon or star you are orbiting is one of those two apsides. THAT apsis is what we are peri- or apo- from in our orbit.

But for the fact that we attempt to keep orbits as circular as possible, generally speaking?  and kerbin is practically synonymous with the earth in the context of the game, correct?

[Superfluous J]

3 hours ago, John Doe said:

But for the fact that we attempt to keep orbits as circular as possible, generally speaking?  and kerbin is practically synonymous with the earth in the context of the game, correct?

No matter how similar, we wouldn't say "-gee". At best, we'd say something like "-kee." At worst we'd not say anything Kerbin specific because we don't know what their equivalent to Greek is

Edited April 25, 2016 by 5thHorseman
Latin is all Greek to me!

[Harry Rhodan]

39 minutes ago, 5thHorseman said:

The "apsis" in "periapsis" comes from the same Latin word,

Greek.

[John Doe]

Well, I have found two things about Kerbin that are different than earth. Apparently, Kerbin's gravity is greater than earth, given the fact that the Kerbal 5, which is around an 85m stack, doesn't accelerate anywhere near as fast as it should, using the figures for earth's gravity. Second thing I've found is that Kerbin's day appears to be at just over two hours or so.

[John Doe]

12 hours ago, 5thHorseman said:

I'm sorry but this is not true. the "gee" in "Apogee" means "Earth" (Because reasons). Similarly, you can speak of "Perilune" for the lowest point in your Moon orbit.

the "apsis" in "Periapsis" is relating to the apsis of your elliptical orbit. There are 2 in each ellipse, and the planet or moon or star you are orbiting is one of those two apsides. THAT apsis is what we are peri- or apo- from in our orbit.

I was wrong above. I'm glad I checked it

The "apsis" in "periapsis" comes from the same Greek word, for the top of a curved archway. In an ellipse, there are two such pointed curved areas, at the "ends" of the ellipse. The end of the ellipse that is closest to the planet is the periapsis, and the furthest one is the apoapsis.

Around Earth, they mean the same thing as perigee and apogee, but they those two won't be correct if used around the Moon, or Mars. The more general terms are correct everywhere.

But, your assuming the orbit is actually elliptical, in the first place. In the situation of a circular orbit, while the same general concept holds true, it also demonstrates that the concept is not necessarily confined to an elliptical shape, but rather apply to an orbit of any shape, If I'm understanding it right. But from what I read somewhere, I'd heard that the terms were always interchangeable and the shorter terms substituted due to NASA's need to simplify the procedure manuals, and that they had started to do this late in the Apollo program and early in the STS program.

 

[Plusck]

35 minutes ago, John Doe said:

But, your assuming the orbit is actually elliptical, in the first place. In the situation of a circular orbit, while the same general concept holds true, it also demonstrates that the concept is not necessarily confined to an elliptical shape, but rather apply to an orbit of any shape, If I'm understanding it right. But from what I read somewhere, I'd heard that the terms were always interchangeable and the shorter terms substituted due to NASA's need to simplify the procedure manuals, and that they had started to do this late in the Apollo program and early in the STS program.

 

Maybe they did, but 5thHorseman's point still stands. Perigee and Apogee are only correct if they relate to Earth.

One would be completely wrong, for example, to say that a comet with a long tail was approaching perigee. People generally use (correctly) perihelion. And Perihelion is only correct when talking about the sun - although "sun" has itself become a generic term for the star at the heart of a solar system so you would be correct to say "perihelion" when talking about the Kerbol system.

As for a circular orbit - it isn't actually possible in reality. There is no simple mechanism for it to occur, because a condensing cloud of gas or dust will always have clumps in it and will always be moving relative to other local masses, so it would take an utterly extraordinary chain of events for a circular orbit to arise naturally. It just doesn't happen. So there will always be a periapsis and an apoapsis.

[Kosmognome]

13 hours ago, John Doe said:

Actually the term Apogee (Pronounced A' Poe' Gee) is synonymous with Apoapsis, and the term Perigee (Pronounced Peri'Gee) is synonoymous with Periapsis. The difference between the two terms is that Apogee /Perigee became the less formal, but more commonly used terms, particularly during the Apollo and STS missions. The latter terms are the more formal terms found in the study of astrophysics within the classroom context. The fact that the game elects to use the more formal terms is unusual given the context of manned flight missions.  

Periapsis and Apoapsis are the general terms that are valid for any celestial body. Apogee is the Apoapsis around Earth. In KSP, you see Apokee and Perkee commonly used for Kerbin when the author doesn't want to use the generic terms.

 

Perilune/Perycynthion/Periselene are all valid for the moon, Perihelion for the Sun etc. Imho the generic terms are much easier to understand - or do you know what an Periareion is? "Mars periapsis" is much easier to understand (or compare pericytherion and perycynthion for venus and moon periapsis...)

[Harry Rhodan]

11 hours ago, John Doe said:

Well, I have found two things about Kerbin that are different than earth. Apparently, Kerbin's gravity is greater than earth, given the fact that the Kerbal 5, which is around an 85m stack, doesn't accelerate anywhere near as fast as it should, using the figures for earth's gravity. Second thing I've found is that Kerbin's day appears to be at just over two hours or so.

The gravity is roughly the same. The actual problem with the old version is that the aerodynamical model is just a placeholder and applies drag as a function of mass to the center of mass to your rocket. That means you are working against an enormous amount of drag. People called the old model "souposphere".

[Superfluous J]

4 hours ago, John Doe said:

But, your assuming the orbit is actually elliptical, in the first place.

Circles are ellipses, and (as the jiggling indicators shows) Ap and Pe don't matter there. I consider them nonexistent.

In the case of hyperbolic or parabolic orbits, those are special cases of course. As has already been said, though, you still wouldn't use "-gee" on the end.

[John Doe]

but, wait even if a orbit is circular, you can still have Ap and Pe. Consider the following orbit, as viewed approximate from the pole. (Ap is 229,450 m and Pe is 182,971 m.) . As we see, however, this orbital path looks nothing like an ellipse. (though I would assume that for an orbit to be truly circular Ap = Pe?? ). I'm really trying to understand obrital paths here a bit beyond what the tutorial really gets at (i.e. how to raise/lower Ap and Pe, and how to tilt an orbit.), I'm trying to figure out how I inserted an engine and fuel tank assembly into an orbit by decoupling it after doing a antegrade burn to deorbit. When I decoupled I was under the assumption that I would fling the the dead engine / tank out into space, or if lucky, into the moon or something.

 

                                                    

Edited April 25, 2016 by John Doe
formating issue

[Superfluous J]

1 hour ago, John Doe said:

but, wait even if a orbit is circular, you can still have Ap and Pe. Consider the following orbit, as viewed approximate from the pole. (Ap is 229,450 m and Pe is 182,971 m.) . As we see, however, this orbital path looks nothing like an ellipse. (though I would assume that for an orbit to be truly circular Ap = Pe?? ). I'm really trying to understand obrital paths here a bit beyond what the tutorial really gets at (i.e. how to raise/lower Ap and Pe, and how to tilt an orbit.), I'm trying to figure out how I inserted an engine and fuel tank assembly into an orbit by decoupling it after doing a antegrade burn to deorbit. When I decoupled I was under the assumption that I would fling the the dead engine / tank out into space, or if lucky, into the moon or something.

 

                                                    

Looking like a circle and being a circle are two different things. For an orbit to be a circle, Ap and Pe MUST be the same. Period. End of story. Don't forget to tip the wait staff.

[Loren Pechtel]

On 4/24/2016 at 1:51 PM, John Doe said:

Actually the term Apogee (Pronounced A' Poe' Gee) is synonymous with Apoapsis, and the term Perigee (Pronounced Peri'Gee) is synonoymous with Periapsis. The difference between the two terms is that Apogee /Perigee became the less formal, but more commonly used terms, particularly during the Apollo and STS missions. The latter terms are the more formal terms found in the study of astrophysics within the classroom context. The fact that the game elects to use the more formal terms is unusual given the context of manned flight missions.  

No.  The game is using the only correct terms.

Apogee = Apoapsis while orbiting Earth.

Perigee = Periapsis while orbiting Earth.

[John Doe]

On 4/25/2016 at 5:58 PM, 5thHorseman said:

Looking like a circle and being a circle are two different things. For an orbit to be a circle, Ap and Pe MUST be the same. Period. End of story. Don't forget to tip the wait staff.

 Not necessarily- If I take a perfect circle and off-set it- its geometrical shape doesn't change, but relative to the object in the center, the Ap and Pe WILL change, Ap=Pe ONLY if we have a perfect circle AND zero off-set in relation to the object being orbited.  The same can hold true for a perfect ellipse- Ap = Pe IF the shape is geometrically perfect AND there is zero offset of the body being orbited. (i.e. the object is perfectly centered within the geometric structure of the orbit.)

[Superfluous J]

12 minutes ago, John Doe said:

 Not necessarily- If I take a perfect circle and off-set it- its geometrical shape doesn't change, but relative to the object in the center, the Ap and Pe WILL change, Ap=Pe ONLY if we have a perfect circle AND zero off-set in relation to the object being orbited.  The same can hold true for a perfect ellipse- Ap = Pe IF the shape is geometrically perfect AND there is zero offset of the body being orbited. (i.e. the object is perfectly centered within the geometric structure of the orbit.)

Except you can't be orbiting something in a perfect circle unless that thing is exactly at the center (disregarding it moving due to your gravitational influence on it) of the circle. And there is no way to orbit in an ellipse without the thing you're orbiting being at one of the foci.