Grand tour 3, cutting corners and other stuff to get below 100 ton.

[magnemoe]

During the previous grand tour I found some weaknesses, Eve lander was to heavy, Tylo lander was to small and both lacked seats.

Moho trip took to much fuel but most of all the first stage was to heavy, made lite sense to drag an orange tank, 400 liter of monopropelant and four LV-N all the way to Tylo.

So I came up with some redesigns to save weight while making the trip safer.

582 ton on pad, 97 ton in orbit, pretty standard asparagus, six trashcans to give some more twr at liftoff. center stage is just one orange tank with padding, the outer tanks has to be extended away from the center as the mothership is around 6 meter wide. The side tanks is to add some more fuel without making them higher.

Neildan Kerman is the lucky pilot, he was offered an job of just testing an new ship and promised an long time employment

Very high on the two important qualities, Courage and stupidity.

During the pilot qualifications he was told to test an solid fueled two stage rocket. Because of an design flaw the four side boosters did not separate.

Neildan desided it was an good idea to do an eva to inspect this, during trust in the atmosphere.

He was pushed off the ladder and ended up on top of the boosters he was able to return to the pod and do an splashdown.

Launch goes well in the start, here the trashcans are ejected.

Because of the large distance between the boosters its no need for seperatrons.

However at this point I suspected I was short on fuel. One way I often use to save fuel is to run the nuclear engines in parallel with the boosters.

I decided to improvise this technique. Disabled all the drop tanks and did manual transfer from lower stage to the mothership tank.

At 75 km I disabled the mainsail and used its tank as an droptank.

I was able to circulate at 120 km using just 30 liter of the mothership fuel who was well below limit.

The ship, 549 parts and 97 ton.

In front is the 8.5 ton Eve lander, below is an 720 liter tank with 4*180 liter drop tanks for the trip to Eve, below it is the Laythe resupply module who would be dropped in high orbit around Layte and will aerobrake down to low orbit. it carries an two stage lander for Laythe.

Then fuel and torque modules. if empty this can be dropped before Laythe and the Layte module can be docked directly to center stage.

The Tylo lander is below followed by the reusable lander who now dock at the front. it let me use one engine to save weight and docking become easier.

One pretty unique part of this design is that the three nuclear engines is connected to three totally different stages, The bottom one is the upper stage who visit all planets and moons, the central one goes to Laythe after Duna and ends at Tylo.

The top one in the image just hold fuel for the Eve to Duna burn, its left then the ship breaks up in Duna orbit.

Its easier to see on the backside picture.

This side only holds the Moho ion stage, an balance fuel tank who can be docked and a small stage who will assist going to Mun and Minmus, it will be left in Kerbin orbit as an backup if I come home dry.

[tavert]

Have you tested your Eve lander with a Kerbal in the seat? The same design that works with a ladder will require more fuel if you use a seat, but I noticed you didn't like the lack of time warp. You can do physical warp with alt-. but that's it with the ladders.

[magnemoe]

Seat is for decent only and is placed on the deorbit drop tank, it will only be manned in the 2-400 m/s deorbiting operation, rest fuel will be spent on takeoff and the tanks is jettisoned. added 20 liter extra fuel to the 90 liter to compensate.

The Tylo lander is a bit more hairy, on it I have to move from seat to ladder either after plane change or after deorbit burn. Will transfer the fuel from the balance tank and jettison it and seat.

Anyway ship is an lag feast, just doing orbital operations close to in is hard.

Here Neildan is eva to the main lander who is in its launch position below the Tylo lander. The 45 liter top tank is for the Mun trip as 2800 m/s is to low for an LKO to the Mun and return.

On Mun ready to go back with details of the lander.

One weakness of the design is that the kerbal might be jettisoned away from lander then leaving seat as its cramped around it.

I landed 2.5 km from the Armstrong monument so I had to visit it, went low on RCS so had to walk almost an km back to the lander.

[magnemoe]

After Mun I docked with the LKO service probe to refuel. It was flawed as the rcs trusters was not aligned to well. Yes the lagfeast of an mothership probably helped.

I found I did not need to dock it to the mothership, the 50 liter fuel is if I have problems then returning to Kerbin. After an short visit to the pod to get more snacks Neildan continued to Minmus.

On way to Minmus I did run into an pretty serious bug.

My minmus transfer would intercept Mun on the return trip, this caused the game to forget the Minmus intercept who was kind of more relevant.

Mechjeb would do burns related to distance to Minmus but the alarm clock did not find the minmus SOI change so I had to take it careful as I did change SOI then I should.

Minmus was routine. Docking was not, I expected that docking the huge unbalanced ship would be an problem, however docking using the autopilot after carefully aligning the ships went well, however the docking port on small struts was not and caused the ship to spin wildly after docking and get damaged, jumping to control center and back at the point of docking solved this. I just tested docking on the front of the smaller upper stage. Anyway, I will just dock once more with the main stage doing Gilly.

[magnemoe]

Look like I have to relaunch, the Eve lander has two serious problems.

This was the minor one, the kerbal on seat at one side tilted the lander during parachute decent. The pilot actually fell off the seat but was saved by the lifebelt tank.

The sideway landing snapped one landing leg and the char fell off.

This problem could be solved by pumping fuel from the deorbit burn tanks under the kerbal to the tank on the other side.

The serious problem was that while first part of accent went without problem it looked like the kerbal unbalanced the lander after separating the last of the side boosters it starting to go off course, on reignite for circulation the lander became totally uncontrollable.

This was not an problem on the previous 9 engine lander and the previous Tylo lander, Unfortunately both the new Tylo and Moho landers uses copies of the eve lander upper stage.

So I will have to find and fix this problem, fix the eve lander balance problem at the same time then relaunch the mission.

The good news is that the trip to Eve worked well, I used 1476 liter fuel 35 over budget.