How would you define a Grand Tour?

[regex]

I've been contemplating doing one of these using a single Kerbal lander and a truck that needs refueling at each stop. I have a save set up and it's about half-way ready, with most of the tankers either on their way or already waiting. Then I got to thinking about doing a "micro Grand Tour" with a single probe core that could transfer between vehicles when needed (Tylo, Laythe, and Eve require their own special landers, for instance) but a probe can't plant flags so there's no "evidence" of it actually happening.

Does a Grand Tour need Kerbals? How many Kerbals need to land on the surface of a body for a landing to be "official"? Does a probe core count? Does the ship need to be entirely self-contained (lordy, 23km delta-V is a ton of fuel...)? Are tankers legit?

How do you define a Grand Tour?*

* Yes, I realize that everyone has their own playstyle and all that touchy-feely stuff. I want your opinion on the matter, I don't want you to define a Grand Tour for me.

[The Destroyer]

In my opinion, a grand tour is any mission that lands on all the planets without refuling

Kerbals are a bonus too.

[Johnno]

Single craft leaving Kerbin's orbit to enter orbit around each body in the system and landing (and returning) a probecore or kerbal on each of them excluding Jool and Kerbol (sun). No refuelling by other crafts and no splitting up to send landers/crafts to several locations.

So basically a 'mothership' with (if you want) a dedicated lander for each location, but I'd still say the command part has to return back to the mothership after each visit, so it's not enough just to drop a probe onto the surface.

That's my personal view of a grand tour. And split between manned/unmanned.

[EvilotionCR2]

In MY opinion, a grand tour is any mission that lands on all the planets with possible refueling.

[bigdad84]

The way I would explain it myself, would be using the same "mother ship" going from planet to planet. Landers designed for said planet will be waiting unmanned for the "mother ship". Along with tanks of fuel set up in places along the way.

[lazarus1024]

Visiting every planet and moon with the same lander and mothership. Refueling is just fine.

I have never done one. I have personally envisioned it as a mother ship that is towing along a single lander. At each planet is a refueling tanker as well as the staging necessary for that planet for the lander.

IE so Moho would have a tanker in orbit already and it might have a landing stage to add to the lander. Seperate the lander, attach to landing stage from the tanker, land on Moho, plant flag, launch from surface, detach landing stage (if there was any fuel to use for part of ascent), meet up with mother ship, refuel everything, launch for Eve. Get to Eve, get landing and ascent stages from tanker, land, plant flag, launch, meet up with mother ship, refuel, etc, etc.

[SpaceSphereOfDeath]

What larzarus1024 said

[architeuthis]

NASA's Planetary Grand Tour, where I assume the name commonly used in the KSP forums comes from, refers to the old name for a scaled up version of the Voyager missions which would have used gravitational slingshots to visit Jupiter, Saturn, Uranus, Neptune and Pluto taking advantage of a special planetary alignment which happens only once every 175 years. The gravity slingshot technique was first used on the Mariner 10 mission which performed flybys of Venus and Mercury. Which is pretty badass when you think about it. The Grand Tour was cancelled by Nixon in 1973.

So my less conventional definition (in KSP parlance anyway), it this: a single mission which uses gravity assists to visit all outer planets, inner planets or some combination thereof.

[regex]

Thanks for everyone's opinions so far, some interesting stuff here.

In case you didn't get it from my OP, my definition is:

Single craft that visits each major body in the Kerbol system, refueling optional (I'd use tankers because **** 23km/s of delta-V), with landers either waiting at each location or lander carried (I'd carry a generic lander with specials waiting for Laythe, Tylo, and Eve), Kerbals optional but the crew (or probe body) must make the entire trip, with one (or more) of the crew landing at each land-able location and returning to mothership.

[gslarmour]

I am going to go with NASA's definition, in that they wanted a set of probes to visit each of the outer planets. In KSP terms, I would say that a grand tour would have to visit each of the major planetary bodies in the Kerbol system. No refueling or landing necessary, just obtaining orbit would count. Visiting any moons would be bonus.

[SRV Ron]

A Grand Tour, NASA style, is really a mission where you use one craft and visit each one of the planets using slingshot maneuvers to boost your speed, or slow down, to fly off to the next one in the tour. The Kerbal Tour would be one where you would use one ship to drop off probes to land or orbit each planet on the flyby. The ultimate tour is being able to land and return a probe ship to the mothership. To be efficient, the mothership would not orbit but instead return on another slingshot retrieving the lander during the second flyby.

If you can get a capture orbit using a very small delta V, so much the better for landing and recovering the probe. Then, take advantage of escaping with prograde or retrograde boost depending on where you want to go next.

You definitely want to hit those flyby directly on plane to get the max effect of the slingshot.

Edited September 3, 2013 by SRV Ron

[magnemoe]

In MY opinion, a grand tour is any mission that lands on all the planets with possible refueling.

Yes, I have done three successful grand tours. first was with an kethane miner lander and an mothership.

The two other with an two stage ship without refueling, however it used an lower stage who acted as an fuel depot and carried the Eve and Tylo. The lower stage only went to Eve, Duna, Laythe and ended at Tylo. while the upper stage landed on all planets and moons.

Sending one ship everywhere without any refueling would be an nightmare because of the Moho dV cost, Might be possible if you only do slingshots in SOI, however setting up an slingshot who take you from Eve to Moho and on to Duna intercept would be hard.

On the other hand placing fuel depots and optional landers at every body with separates launches would make this no harder than any other mission.

[regex]

Sending one ship everywhere without any refueling would be an nightmare because of the Moho dV cost

It really depends on where you transfer from, but any return from Moho is going to be murderous. My Grand Tour plan is some five years long and goes (IIRC) Kerbin -> Dres -> Jool -> Eeloo -> Duna -> Eve -> Moho -> Kerbin. The two big hurdles are Dres -> Jool and Moho -> Kerbin. On the Moho -> Kerbin transfer I planned to leave the lander behind so as to have more than a paper-thin margin of extra delta-V. Either of those two transfers benefit from aerocapture so I suppose it wouldn't be all that big of a deal.

On the other hand placing fuel depots and optional landers at every body with separates launches would make this no harder than any other mission.

I can't argue with that, but some of us have parts count to worry about. Still, I might try doing without for a micro tour.

[Respawn]

I have also been thinking of doing a grand tour.

My current thinking is to build a craft that carry all landers needed, and plant a flag on all planets+moons with surfaces.

However once the landers have been used they'll be left behind.

I would start with Eve so I wouldn't have to carry the eve lander along through the rest of the mission,

then to wherever my next heaviest lander would be used.

Shedding weight as i go.

I'm thinking of assembling it in orbit.

Every major part being attached when leaving LKO.

Only 1 kerbal planting all the flags.

No refueling. But i'm not sure if I can figure out how yet.

Still in the earlier stages of planing this mission.

I might even wait for 0.22 and do some science stuff on the way.

[magnemoe]

It really depends on where you transfer from, but any return from Moho is going to be murderous. My Grand Tour plan is some five years long and goes (IIRC) Kerbin -> Dres -> Jool -> Eeloo -> Duna -> Eve -> Moho -> Kerbin. The two big hurdles are Dres -> Jool and Moho -> Kerbin. On the Moho -> Kerbin transfer I planned to leave the lander behind so as to have more than a paper-thin margin of extra delta-V. Either of those two transfers benefit from aerocapture so I suppose it wouldn't be all that big of a deal.

I can't argue with that, but some of us have parts count to worry about. Still, I might try doing without for a micro tour.

One tip, use an ion powered probe with an seat for the Moho->Kerbin return, make it so you can dock the Moho lander to it as an fallback if you run into trouble braking for Moho, leave an lander behind in LKO for the Kerbin landing.

If you keep weight down ion engines has legs and the acceleration is so bad compared to something nuclear with 10 km/s dV. (the 0.13 twr is in high Eve orbit)

This did Eve Moho Eve with 1500 m/s margin and I did not bother waiting for an good intercept, yes I could get far more dV out of it if I discarded the other part so it was overbuild.

And part count is the serious killer. over 500 for my latest ship.

One idea might be to split the ship after leaving Kerbin SOI, one part go out system to Dress, Jool and Eeloo, the other wait for an Kerbin slingshot to get it to Eve, might want to send an small resupply module to Duna for the 2000 m/s you need to get to Eve.

[Horn Brain]

I don't think defining it as launching one ship (even possibly with a separate lander) which orbits and lands on all possible bodies without refueling is totally realistic. Ignoring for a second the landing bit, let's say you wanted to send a ship to orbit all the possible bodies in the game. If you want to get into low orbits around the planets and not just get captured (which makes sense since you'll probably have to move your periapsis for an efficient ejection burn later anyway), even considering as free all the potential aerocaptures, I ran one route and estimated about 20.5 km/s dV. That means you need a mass fraction of propellant of 92.68% using nuclear engines. The mass fraction of a kerbal tank is 88.9%. So just a tank, without any engines, crew, power systems, or anything else, does not have enough dV in it even if you could propel it with a magical massless nuclear engine. When you talk about adding a lander (or realistically a set of landers, since there is no way you're going to land something on Eve and Tylo and return) to that, it becomes impossible. You'll have to use Kethane or just cheat. The grand tour should not be accessible only to Kethane users.

Also, hauling around all the different landers you'll need is stupid from a design standpoint! Why pay the fuel cost to haul a big, heavy lander to a planet that it won't even be landing on? It's much more efficient to just deposit all the unique landers you'll need at their locations and just carry around a general purpose lander that can land on most of the other worlds.

I realize there are more fuel efficient paths through the system, especially if you use aerobraking (which is ridiculous for such a large ship but ok), but to get the mass fraction down to the tank mass fraction you only have 17.2 km/s. Even with staging, that would be practically impossible, and that's only orbiting, not carrying landers and their fuel!

I would like the only rule to be all tankers should have to be deposited (or at least launched and on their way to their destinations) BEFORE you depart your mission. That demonstrates the planning required, which I think is the real core of this challenge, not whose computer can chug through the most enormous ship.

1.) Fly through all the planetary and dwarf planetary SoIs in the game with one ship. Manned/unmanned doesn't matter. Hard mode: no refueling (use slingshots)

2.) Orbit all the planets and moons in the game with one ship, picking up fuel from PRE-deposited tankers along the way. Manned/unmanned doesn't matter.

3.) Land on all the planets and moons in the game. Manned/unmanned is a serious distinction here:

a.) Manned: You must land and return your kerbals from the surface of every world possible. You may predeposit tankers and landers at necessary locations.

b.) Unmanned exploration: You need only to deposit a probe on the surface of each world possible. Return is not necessary.

c.) Unmanned sample return: You must land and return a probe with some small payload from each surface. For science.

Edited September 4, 2013 by Horn Brain
First sentence was borked. I mean it ISN'T REALISTIC

[regex]

One tip, use an ion powered probe with an seat for the Moho->Kerbin return

LMAO, that's pretty awesome.

I don't think defining it as launching one ship (even possibly with a separate lander) which orbits and lands on all possible bodies without refueling is totally unrealistic. Ignoring for a second the landing bit, let's say you wanted to send a ship to orbit all the possible bodies in the game. If you want to get into low orbits around the planets and not just get captured (which makes sense since you'll probably have to move your periapsis for an efficient ejection burn later anyway), even considering as free all the potential aerocaptures, I ran one route and estimated about 20.5 km/s dV. That means you need a mass fraction of propellant of 92.68% using nuclear engines. The mass fraction of a kerbal tank is 88.9%. So just a tank, without any engines, crew, power systems, or anything else, does not have enough dV in it even if you could propel it with a magical massless nuclear engine. When you talk about adding a lander (or realistically a set of landers, since there is no way you're going to land something on Eve and Tylo and return) to that, it becomes impossible. You'll have to use Kethane or just cheat. The grand tour should not be accessible only to Kethane users.

Excellent point.

I would like the only rule to be

One thing: This is an opinion thread. I'm just wondering what people's opinions are on the whole concept of the Grand Tour. I'll sure as hell define it the way I want to in my game, but it's always nice to see how other people think about it; it gives me more ideas for challenging myself (and hopefully everybody else gets the same benefit!)

all tankers should have to be deposited (or at least launched and on their way to their destinations) BEFORE you depart your mission. That demonstrates the planning required, which I think is the real core of this challenge, not whose computer can chug through the most enormous ship.

While I like your second point, at least two of my tankers are leaving after the main ship because of launch windows and arrival time coincidence. I really like the specificity of your other rules.

[Geschosskopf]

My own opinion of what constitutes a "grand tour" stems from my refusal to simply land, plant a flag, and leave. There needs to be exploration and, if warranted, exploitation as well. Otherwise, what's the point of spending all the money to go there? So, at the very least, I feel you need to make a complete ISA MapSat map of every world, scan it for Kethane and/or ore if you have those mods, and if all these give you good results, use this information to build something permanent there.

So the way I envision a "grand tour" involves 2 main multi-part ships. One is a generic lander for most no-atmosphere places, Laythe, and Duna, a can of Kerbals, a Kethane refinery, and the nuclear tug to push it around. The other is a reusable ISA/Kethane/Ore probe with enough delta-V to get to and from a polar orbit, a robot lander with Kethane drills for most no-atmosphere places, and a nuclear tug to push it around. These 2 ships wander around between the planets as the launch windows blow, keeping themselves refueled along the way, and doing all the survey work. Eventually, they will visit very system so would do a "grand tour".

This is all supported by, and in turn supports, groups of specialized ships for specific places sent out directly from Kerbin. So, specialized landers for Tylo, Eve, and Duna, airplanes and airbases for Eve, Duna, and Laythe, and dedicated probe/Kethane drill/tug assemblies for Gilly, Ike, and Pol to service long-term occupations within the Eve, Duna, and Jool systems. Other permanent installations and Kethane refineries for these system will follow once the initial footholds are established. At present, there doesn't seem much point in establishing a permanent presence at Moho, Dres, or Eeloo, but they at least need to be mapped and scanned "for science" and future reference.

Anyway, that's the ultimate plan. But it's a very time-consuming to do. Thus far, I haven't even got the Duna part fully set up yet, although I do have some stuff en route to Dres and Jool to be there waiting when the main show gets there.

[Jesuss]

Landers designed for said planet will be waiting unmanned for the "mother ship". Along with tanks of fuel set up in places along the way.

[magnemoe]

Also, hauling around all the different landers you'll need is stupid from a design standpoint! Why pay the fuel cost to haul a big, heavy lander to a planet that it won't even be landing on? It's much more efficient to just deposit all the unique landers you'll need at their locations and just carry around a general purpose lander that can land on most of the other worlds.

You need an separate lander for Eve and Tylo obviously. Will also recommend an separate one for Laythe however the rest can be done with one lander design with an 45 liter tank, and a 48-S7.

For Moho it might be an idea to dispose the lander saving weight going back.

I realize there are more fuel efficient paths through the system, especially if you use aerobraking (which is ridiculous for such a large ship but ok), but to get the mass fraction down to the tank mass fraction you only have 17.2 km/s. Even with staging, that would be practically impossible, and that's only orbiting, not carrying landers and their fuel!

In practice you will use more as it will take forever waiting for the right transfer points.

http://forum.kerbalspaceprogram.com/showthread.php/46340-Grand-tour-2-Jeb-s-revenge

Has some practical dV cost estimates, this was done as an new game so it should be be easy to get the same values.

I used an two stage ship, it let me get away with the extremely expensive Moho trip with less mass, and only the upper stage stopped at Dress, it was also the only part who continued past Tylo.

I would like the only rule to be all tankers should have to be deposited (or at least launched and on their way to their destinations) BEFORE you depart your mission. That demonstrates the planning required, which I think is the real core of this challenge, not whose computer can chug through the most enormous ship.

1.) Fly through all the planetary and dwarf planetary SoIs in the game with one ship. Manned/unmanned doesn't matter. Hard mode: no refueling (use slingshots)

2.) Orbit all the planets and moons in the game with one ship, picking up fuel from PRE-deposited tankers along the way. Manned/unmanned doesn't matter.

3.) Land on all the planets and moons in the game. Manned/unmanned is a serious distinction here:

a.) Manned: You must land and return your kerbals from the surface of every world possible. You may predeposit tankers and landers at necessary locations.

b.) Unmanned exploration: You need only to deposit a probe on the surface of each world possible. Return is not necessary.

c.) Unmanned sample return: You must land and return a probe with some small payload from each surface. For science.

Pretty much agree on the rules here, however the unmanned exploration might be better to do this the other way around, going out by Duna, Dress, Jool system, Eeloo, then down to Eve and aerobrake, before sending the last ion top stage to Moho. The killer her will be the part count with all the landers. More so as you would want drop tanks on them so you don't have to go deep into the gravity well to deploy the landers.

Sample return is roughly as hard as returning an Kerbal, You only save the weight of kerbal+ seat, using the sample return mod and its actually harder.

[magnemoe]

My own opinion of what constitutes a "grand tour" stems from my refusal to simply land, plant a flag, and leave. There needs to be exploration and, if warranted, exploitation as well. Otherwise, what's the point of spending all the money to go there? So, at the very least, I feel you need to make a complete ISA MapSat map of every world, scan it for Kethane and/or ore if you have those mods, and if all these give you good results, use this information to build something permanent there.

So the way I envision a "grand tour" involves 2 main multi-part ships. One is a generic lander for most no-atmosphere places, Laythe, and Duna, a can of Kerbals, a Kethane refinery, and the nuclear tug to push it around. The other is a reusable ISA/Kethane/Ore probe with enough delta-V to get to and from a polar orbit, a robot lander with Kethane drills for most no-atmosphere places, and a nuclear tug to push it around. These 2 ships wander around between the planets as the launch windows blow, keeping themselves refueled along the way, and doing all the survey work. Eventually, they will visit very system so would do a "grand tour".

This is all supported by, and in turn supports, groups of specialized ships for specific places sent out directly from Kerbin. So, specialized landers for Tylo, Eve, and Duna, airplanes and airbases for Eve, Duna, and Laythe, and dedicated probe/Kethane drill/tug assemblies for Gilly, Ike, and Pol to service long-term occupations within the Eve, Duna, and Jool systems. Other permanent installations and Kethane refineries for these system will follow once the initial footholds are established. At present, there doesn't seem much point in establishing a permanent presence at Moho, Dres, or Eeloo, but they at least need to be mapped and scanned "for science" and future reference.

Anyway, that's the ultimate plan. But it's a very time-consuming to do. Thus far, I haven't even got the Duna part fully set up yet, although I do have some stuff en route to Dres and Jool to be there waiting when the main show gets there.

That was my fist grand tour, huge kethane miner with mothership/ transfer stage. Main downside was as you say it was time consuming.

The miner could land return from all bodies except Eve, on Tylo it had to mine before leaving. I used orbital construction to spawn satellites, had an small lander for findng landing spots on low gravity worlds.

[Van Disaster]

My own opinion of what constitutes a "grand tour" stems from my refusal to simply land, plant a flag, and leave. There needs to be exploration and, if warranted, exploitation as well. Otherwise, what's the point of spending all the money to go there? So, at the very least, I feel you need to make a complete ISA MapSat map of every world, scan it for Kethane and/or ore if you have those mods, and if all these give you good results, use this information to build something permanent there.

I see it as the space equivalent of backpacking tourism; I'd much rather send better equipped specialist missions to exploit systems. If I ever did a tour I might take a rover along and I'd definitely want to make whatever I took self sufficient ( I use Kethane anyway, so that's not that big a deal ). I suspect any tour I did would be a trip to all the anomalies.

[Unistrut]

Well, the original Grand Tour was a sweep through Europe to see the various culturally significant sights, I'd say that you need to take one vessel and go see the solar system, without returning to Kerbin after every stop. Meeting up with a refueling barge or doing some resource extracting is to be expected given the dV requirements of the trip. I'd avoid mapping / scanning or anything that requires a polar orbit as that just makes your transfer burns way harder.

[CatastrophicFailure]

[2¢]did one of these in the latter days of .20, didn't start out as a grand tour either. Originally the plan was for a tour of Jool's moons. Then I decided to do the whole shebang long as I'm out there. Had a hybrid ion powered mothership with room for three Kerbals to be COMFORTABLE (not just crammed in a single capsule for a dozen years) that was otherwise fairly small, and dragged a basic lander around with it. I sent it out new docking adapters first, then tankers and mission specific landers as & where needed. Route was Jool-Eeloo-Dres-Duna-Eve-Moho-Kerbin. Even managed to land back at KSC with a Soyuz capsule. Landed on every land able body except Eve, and left a flag everywhere but Moho since my rover picked up a bad case of the random explosions there and I left in a hurry. [/2¢][br]. [/br]Lessee here.....[br]. [/br]Side note, WTF aren't line breaks working???

Edited September 4, 2013 by CatastrophicFailure

[thereaverofdarkness]

I think the minimum definition is flinging a ship around to three or more separate destinations in separate Kerbol orbits using the gravity slingshot and/or onboard fuel--and getting within picture-taking range. It doesn't count if you don't have anything to show for it at the end. You could use fueling stations too, as long as you're getting a nice visit to everything and taking pictures.

I think anything more is for posterity and is great, I think you should make your grand tour as awesome as you can. But if someone else has a weak grand tour, it's still a grand tour.