Flieger, grüß' mir die Sonne, grüß' mir die Sterne und grüß' mir den Mond. Dein Leben, das ist ein Schweben, durch die Ferne, die keiner bewohnt! - Hans Albers, F.P.1 antwortet nicht (Adaptation in the 80s: Extrabreit)

Monday, 27 July 2015

Design of a Yawl

While I just could get ahead with my numerous space expeditions, something still bugs me. The dinghys which I was able to design so far can only transport one passenger. This must be a scientist, so that I can reuse all that scientific equipment. But what if a wheel blows up? I can compensate for only one, by substituting with the landing gear. It would be better if my dinghy had room for two or more crew, so that an engineer can be on board, as well, to repair that wheel or to pack parachutes (concerning the Duna landing).

So I get distracted again and spend one and a half game sessions in the VAB.

- Calamari Lander

Ok, this thing can carry a crew of four and has all scientific stuff on board. I do not worry too much about its mass, the Navitas can afford it. Special about it is the vertically aligned Spark engines. The ore dish is only for balance purpose. And it makes it look like a calamari. Hm, not sure if I like this design.

In between, there are some routine maneuvers, namely, the third pass of both the Fuel Ship and the Scientia 2 for their aerobraking.

- correcting orbital angle to an equatorial one

- how many more passes do I need, I wonder ...

- ... but my Kerbonaut here has fun

Then back to my unfinished design. It also gets some parachutes added, for a fuel-saving Duna landing later on. I want to test if the vessel is capable to land like this. So I add a launch stage for about 70,000 credits, launch, and then stage it at about 4,000 meters. The parachutes work very well, the vessel lands like a feather and does a qualifying test parcours around the Space Center.

Then my mistake: Instead of reverting the flight, I recover the rover, as I used to do during my past tests of the Crab Rover et alia. The moment I press that button, I realise my mistake, but too late; 70,000 Credits are blown out of the window. Dang! This is a little taste of how frustrating the game would be on hard mode, where every little mistake can blow your finances and thus ultimately make you fail your career due to lack of finances.

A little adaptation, making the vessel not really look a calamari anymore, and I want to do a test orbit and de-orbit with my new design. Since this is a kind of picture story again, let me test how linking this one to an imgur account works out:

View post on imgur.com

Uhm. Not very well. Anyways.

- Yawl

The main problem seems to be the wrongly aligned navball, making it difficult to find the proper direction, especially when trying to line up to a maneuver node. This is due to the SAS unit facing forwards instead of upwards, to account for the vertical trust vector instead of the normal, horizontal one. Hm, maybe using the one manned Crab Lander would still be the better idea? Not sure; it is the crappy thrust of its Terrier engine when in an atmosphere, which bothers me. After all, I want to land on Duna and be able to take off again.

- the Crab Lander´s TWR doen´t look too good on Duna

In comparision, the four Spark engines which I chose for the Yawl are going to produce much more reliable thrust in Duna´s atmosphere.

 - after some little tweaks, still not really as elegant as I hoped, but the thrust is acceptable

So, it is time for another test run on Mün, I suppose. Launch almost goes wrong, when the rocket suddenly flips at about 20km altitude. I manage to regain control, but at the cost of having only 500m/s deltaV left in orbit, compared to the 1500m/s which it should have left over.

Then I realize another mishap; one rover wheel has blown. Since I do not have any engineer at the required experience level, I cannot repair it during an expedition and thus my test flight already failed. I wonder how this could have happened. After a reload, the case becomes clear; my latest design tweaks had caused a rover wheel to clip through the fairing. However, this gives me the occasion to not only correct the fairing´s shape, but also to add a docking port on the top. Like this, I can switch the nav ball´s perspective of control from the usual horizontal view to a vertically aligned view, by clicking on the docking port and choosing the option "control from here". I learned this in one of the many gameplay videos. Also, the closer the point of control is to the center of mass, the less erratic the SAS seems to be.

Launch goes well this time, I manage a remotely fine gravity turn. Once in orbit, I plot an intercept in order to fuel the Yawl up again. Then I am going to send it to Mün orbit, dock to the Scientia to take over some crew and then do some landings with both the Yawl and the Crab, to compare their actual performance.

 - the Yawl is in orbit, and on intercept to the Fuel Dragon

Real life does not let me have the time I want, so I logout and resign to write about what little progress I achieved during those meager two game sessions since my last blog entry.

No comments:

Post a Comment