Project Rockot launcher

[IronRain]

Looks very nice! Keep up the good work :thumbup:

Thanks, I will :tiphat:

 

[SiberianTiger]

It's about time... Tomorrow at 2 p.m. UTC a Rockot launch will commence.

 

[Urwumpe]

It's about time... Tomorrow at 2 p.m. UTC a Rockot launch will commence.

Don't you think you overpressurize the system? :lol:

Looks already great IronRain, take the time you need, I couldn't make it better!

 

[IronRain]

Looks already great IronRain, take the time you need, I couldn't make it better!

Thanks :tiphat:

 

[Wishbone]

IronRain, take care and the fastest recovery to you!

 

[IronRain]

IronRain, take care and the fastest recovery to you!

Thanks :tiphat:

I have a question.. well, actually I wanna know if I'm right.

The specs of the first are:
Gross mass: 77,150 kg (170,080 lb).
Unfuelled mass: 5,695 kg (12,555 lb).
Height: 17.20 m (56.40 ft).
Diameter: 2.50 m (8.20 ft).
Span: 2.50 m (8.20 ft).
Thrust: 1,778.66 kN (399,859 lbf).
Specific impulse: 310 s.
Specific impulse sea level: 285 s.
Burn time: 121 s.
Number: 178 .

which I translated to:
MESHNAME="Rockot\stage1"
OFF=(0,0,0)
HEIGHT=17.2
DIAMETER=2.5
THRUST=1778660
EMPTYMASS=5695
FUELMASS=71455
BURNTIME=121
SPEED=(0,0,-2)
ENG_1=(0.8,0,-8.3)
ENG_2=(-0.8,0,-8.3)
ENG_3=(0,-0.7,-8.3)
ENG_4=(0,0.7,-8.3)
ENG_DIAMETER=0.8
ENG_TEX=Exhaust2

Well, most things are right, but I'm not sure about the masses and thrust values. Are these correct?

 

[Urwumpe]

If you want me to be terribly correct:

You should increase the empty mass a tiny bit for accounting for residual fuels and fuel trapped inside the wet engines. I just checked the fuel consumption, the fuel mass would be enough for 122 seconds, one second of operation more, so you should add 584.87 kg to the empty stage mass as residuals.

Then the specific impulse should be right on target and the sea level thrust could be made accurate. Which you don't include yet, since you have no specific impulse lines yet.

 

[IronRain]

If you want me to be terribly correct:

You should increase the empty mass a tiny bit for accounting for residual fuels and fuel trapped inside the wet engines. I just checked the fuel consumption, the fuel mass would be enough for 122 seconds, one second of operation more, so you should add 584.87 kg to the empty stage mass as residuals.

Then the specific impulse should be right on target and the sea level thrust could be made accurate. Which you don't include yet, since you have no specific impulse lines yet.

Thanks,

I got the info from Astronautix, but I've heared that it's not completely reliable..

Main Engine RD-0233/RD-0234  
Fuel  N2O4 / UDMH 
Sea Level Thrust  1870 kN (each engine 470 kN) 
Vacuum Thrust  2070 kN (each engine 520 kN) 
Sea Level Specific impulse: 285 s 
Vacuum Specific impulse: 310 s 
Burn Time 121 s

This is from the PDF. I've missed this table, so this is the first time I see it.. How should I implant the sea level specific impulse?

 

[N_Molson]

About the mass, here are the figures from Khrunichev, the builders themselves :

http://www.khrunichev.ru/main.php?id=43&hl=rockot

 

[Urwumpe]

Thanks,

I've got the info from Astronautix, but I've heared that it's not completely reliable..

That is not entirely correct - Encyclopedia Astronautica is VERY accurate and reliable, and if it is not, you can let Mark Wade correct it.

But Mark Wade is no spaceflight engineer, he edits the homepage from the view of a historian, squeezing the known data into a template that permits easy comparison and put developments in relation, but you need to remember what each value on the homepage really means, if you want to turn it into simulation model.

Main Engine RD-0233/RD-0234  
Fuel  N2O4 / UDMH 
Sea Level Thrust  1870 kN (each engine 470 kN) 
Vacuum Thrust  2070 kN (each engine 520 kN) 
Sea Level Specific impulse: 285 s 
Vacuum Specific impulse: 310 s 
Burn Time 121 s

This is from the PDF. I've missed this table, so this is the first time I see it.. How should I implant the sea level specific pulse?

There should be an option in Multistage to set the two ISP values, if there is not (I always do DLLs, not Multistage2 files), you should ignore me.

 

[IronRain]

There should be an option in Multistage to set the two ISP values, if there is not (I always do DLLs, not Multistage2 files), you should ignore me.

No, only for boosters, not for stages.

CURVE_i: (t,l) defines the booster thrust level versus time (t is for time in seconds , l is for
thrust level in percent of maximum thrust). Thrust level is interpolated between specified
times. The profile can contain a maximum of 10 points (i stands for 1, 2 .. up to 10). If no
curve is defined then 100% thrust is applied all the time.

I could consider the first stage as a booster.. When do you say it's an booster and when do you say it's a stage? Or is there no rule for this?

 

[Urwumpe]

I think you confuse a few things.

CURVE is for implementing thrust curves, like solid rocket boosters have. This function does not change the specific impulse.

 

[IronRain]

man, that's noobish, I'm sorry Then it's not possible.

 

[thegrogen]

That is not entirely correct - Encyclopedia Astronautica is VERY accurate and reliable, and if it is not, you can let Mark Wade correct it.

Some would disagree...

 

[Urwumpe]

Some would disagree...

Many more would agree, and that is good enough for me. :thumbup:

(Also, reading the criticism there, I would say some people should really buy the dictionary "NASA-English/English-NASA" - Mark Wade has the assessment right, while they argue about how to reinterpret a NASA directive in their favor.

Explanation: "Termination of the procurement of long-lead time items" means stopping ordering new parts for a program, that need many months/years for being produced after placing an order. From that point on, you work from stockpiles and the backlog of orders that had already been placed. That is not the cancellation of the Saturn V, since you could still at a later time order new long-lead time items without even a gap in the production of the vehicle, if you change your plans.

Canceling the Saturn V means no longer ordering new vehicles and only finishing those vehicles, that have already started production. While the last vehicles are assembled, the first steps in the production pipeline are already de- or retooled.)

 

[IronRain]

I'm going to try not to make this a project which will be abandoned in a couple of weeks/months, but I don't promise anything.

So here we go for another round! ATM, I'm busy with meshing all the stages and other parts with the skills that I've learned since the beginning of this project (almost 3 years ago :shifty.

Before I post some new shots of the launcher, I would like to request some information. I'm looking for some specifications of the RD-0233 engine like the diameter en height. Some kind of diagram would also be appreciated. Of course I've searched the web, but maybe some of our Russian friends can provide me a bit more information

 

[IronRain]

Here we go again!

Meshing is almost done. Next step is (still) the hardest part; texturing.

Once complete I'll begin working on the MS2015 files and try to get here off the ground.