RRoan
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Posts posted by RRoan
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I'm a little confused: does this mod add any parts or does it only contain reworks of the stock parts?
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(The Ares V and SLS are almost identical anyway, and those SRB's look like they would make a great Ares I.)
Yes, if your definition of almost identical is "really big and orange with solid boosters".
Ares V was a hilarious 200-ton lifter, while the SLS is a 70-ton lifter that might eventually be upgraded to 130 tons.
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Not quite. ÃŽâ€v is independent of burn time (assuming you discount factors such as inefficiencies due to burning during less optimal times during your orbit, which are non-trivial, but can be reduced by using multiple 'kicks' rather than one long one). If you want to change your orbit to a specific orbit for a transfer, you need to have a specific amount of velocity. The change in velocity you need to achieve at the burn point is known as required ÃŽâ€v. This is number is independent of the mass of a craft, and is derived only from it's current orbit and the orbit you want to achieve. This is how the ÃŽâ€v maps work. It takes (roughly) 2000 m/s to reach Jool, regardless of whether you are flying a 2 ton probe or a 200 ton colony ship.
You are correct in saying increased mass decreases your available ÃŽâ€v. However, increasing thrust while keeping ISP constant (e.g. by adding more engines) will never increase your available ÃŽâ€v, even if you had zero-mass engines available. ISP is, quite simply, a measure of how much ÃŽâ€v you can get out of a given amount of fuel. To make it clear why this is, imagine you have a spaceship that consists of nothing but fuel tanks and two identical, weightless engines. If you were to run both engines, you would get 2X kN of thrust, where X is one engine's worth of thrust. If you were to shut off one of the engines, you would have only X thrust, meaning it would take twice as long to complete a burn. However, since you are only running one engine instead of two, you consume only half as much fuel in a given period of time, say 1 second, as you would with both engines running. At the end of the burn, both factors cancel out completely, meaning you have burned the exact same amount of fuel.
This is consistent with basic physics, as you have hurled the same amount of fuel backwards at the same speed (albeit over a longer time period), regardless of the number of engines. Thus, the total momentum change of your rocket is equal.
I'd also like to point out that the program in my sig uses the same calculations as what capi3101 is posting. You can play around with it using different number to verify the results posted (although you'd have to do it backwards, starting with a minimum TWR and ÃŽâ€v). The results are quite significant.
For example, for a 5 ton payload, in order to achieve a ÃŽâ€v of 4000 and a (Kerbin-surface-relative) TWR of 1 when full, you'd need 4 LV-Ns and 9.29 tons of fuel, for a total mass of 23.29 tons.
That same 5 ton payload with 4000 ÃŽâ€v but a relaxed Kerbin-surface-relative TWR of 0.5 requires only 1 LV-N and 4.81 tons of fuel, and has a total mass of 12.06 tons.
The reason 1/4 the number of engines provides 1/2 the thrust is because of the tyranny of rocketry: You need more fuel to carry the increased engine mass, which needs more engines to get thrust needed for the same TWR, which needs more fuel... etc.
Also note that Kerbin-surface-relative TWR (KSRTWR?) is simply an alternative way to represent a given level of acceleration a ship is capable of, since Kerbin surface gravity will always remain at 9.81m/s2 regardless of where you go in the universe. A more logical expression would be the Thrust-to-Mass ratio, where a TMR of 1 would represent the ability to accelerate at 1 m/s per second (1m/s2), but I figured most players would have an intuitive feel for how "thrusty" a ship with ~1-2 KSRTWR feels in space, since most early ships they would design would have about that much thrust.
I did not say that reducing burn time via adding more engines increases ÃŽâ€v, and did in fact say the opposite, so I am unsure why you felt the need to write a multi-paragraph post lecturing me about things I already know. I merely noted that there are cases where an increase in thrust leads to a reduction in the required ÃŽâ€v relative to a design with less thrust, which is completely correct.
TWR and TMR are the same if using proper units.
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The Oberth effect isn't some magical superboost. To get the benefit of the effect, you'd need to add engines to get more thrust. That additional mass is going to reduce fuel efficiency and offset at least part of the benefit gained by the shorter burn. How much is the *net* benefit actually going to be?
A reduction in vehicle ÃŽâ€v due to added weight is fine if it results in a burn that requires less ÃŽâ€v in the first place. And a one minute orbit insertion burn is going to require a lot less ÃŽâ€v than a seventeen minute one.
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A transit to another planet takes tens or hundreds of days, so what difference does it make if the burn takes 1 minute or (with this ship pictured) 17 minutes?
Oberth.
10 character limit is tyranny.
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Do I use ion engines, you ask?
Try doing that with anything else.
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I think it's pretty cool that the emergency fail-safe is to just blow it up.
Not quite; there was a linear shaped charge running most of the length of the booster that effectively "unzipped" the side of it. This has two consequences: it decreases the thrust, since the gas can now escape out the side instead of the nozzle, and it releases the pressure in the chamber. Since the burn rate of solid fuel is very strongly dependent on the chamber pressure, this considerably slows the burn rate and, ideally, would prevent a detonation. The shuttle SRBs were originally going to have a thrust-termination system consisting of upwards-facing nozzles that would counter the main nozzle if opened (and relieve pressure as well), but this requirement was dropped very early on.
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You can't fit 7.5 T45s onto the bottom of an orange tank so you can't get to the thrust of a MainSail with the efficiency of a T45.
I can get 12 T30s and 4 T45s onto a single orange.
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Nearly four hundred nuclear engines have rained down upon KSP in my last ten launches.
If things aren't explodifying often, you aren't pushing the game hard enough.
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Go big or go home.
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85 minutes would show SIGNIFICANT flattening of the star or gas giant.
Achernar, the most non-spherical star known, has a rotation period almost three and a half times longer than that. I can't imagine an 85-minute period would be survivable for many stars, either.
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Congesspeople vote for the budgets they think are cost-effective
This is just wrong. The only time congress gives a damn about spaceflight is when they can use it to get political brownie points, which means either spending a lot of money (in their own district) or doing their best to cut the budget to show they're serious about fiscal responsibility (but only if they don't have spaceflight-related jobs in their district).
Congress being involved in the minutiae of NASA's budget is the single largest problem the agency has.
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I would tell them not to waste exorbitant amounts of money on a flawed concept.
Slapping might be involved as well.
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As far as I know Fuel transfers (and therefore "Asparagus" designs) are really really complicated and hard to do IRL, and as of right now only one rocket does it and that is the new NASA rocket SLS ( http://en.wikipedia.org/wiki/Space_Launch_System )
if I am correct
you are incorrect
the falcon heavy will come with crossfeed
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I'm running a PhenomII 955 quad @ 3.2 ghz with a good cooling system and a NVIDIA GeForce GTX 660 Ti, 8G ram
starts complaining at 750'ish parts.
What are you doing with my computer?
But yeah, that setup works pretty damned decently.
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First thousand-tonne rocket to do a 180 within 20 seconds of launch.
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Fine, let me restate my point: I can't imagine how tedious a non-historically-based film or novel would be if it actually adhered perfectly to reality.
Why on earth do you think an uncompromisingly realistic story would be tedious? Tedious to write, maybe (although you are unlikely to write such a story unless you find the process interesting!), but there's no reason why such a story should be tedious to the reader.
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Is there any possibility of getting some landing gear?
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You don't need a booster to get to Jool.
The engine on this thing is p hilarious. I mean, single-stage-to-jool? lul
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Updated. Also, since I couldn\'t bare to be in last place I did another run.
Can you use simple mods?
On my attempts, I used Mk2 bicouplers and stronger struts, would they count?
I don\'t see a problem with using something simple like that (provided, of course, that it\'s balanced) as long as its mostly stock.
Mechjeb is fine too.
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Added ornitorrincos\' altitude.
Woland: I think you know what I mean. Besides, if you want to play that way I can do it better:
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This is pretty simple; go for the maximum altitude you can with the new air-breathing engines in 1.5. Due to differences in engine performance there will be separate categories for basic jets and turbojets. Obviously, zoom climbs are your friend. I\'ve hit 9,000 meters with jets and 20,000 meters with turbojets, so you can consider that the baseline.
Rules:
-No rockets. Jets and turbojets only. Since it was brought up on IRC, rocket-assisted takeoff is okay. But only takeoff. D:<
-Post a screenshot of the maximum altitude.
-Make sure to post whether you\'re using jets or turbojets.
-You need to take off via the runway. Horizontally.
Jet records:
1. Mr Monkey Pie - 16,867 Meters
2. keptin - 13,516 Meters
3. OstermanA - 11,990 Meters
4. ornitorrincos - 11.529 Meters
5. Xiren - 10,377 Meters
6. andrewthecool - 9735
7. RRoan - 9,000 Meters
Turbojet records:
1. Keptin - 38,008 Meters
2. woland - 35,696 Meters
3. danielw8 - 35,274 Meters
4. OstermanA - 26,593 Meters
5. RRoan - 24,979 Meters
6. Nematrec - 24,636 Meters
7. SteevyT 23,973 Meters
8. Xiren - 21,762 Meters
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That's it, I give up...
[1.0.5] Atomic Age - Nuclear Propulsion - Red Hot Radiators
in KSP1 Mod Releases
Posted
Same. The conflict is definitely FAR. Tested it with a fresh install with nothing but Atomic Age and FAR installed.