Rocketry and so on.

[Tobius]

Do you know what harmonic air flow around a cylinder is, and what happens when boundary flow is rolled at mid-cylinder? The cylinder will snap in two in the direction of strain. Like breaking a twig in two.

A rocket will HUM at you. That flies right. If it starts shaking and oscillating and a reaches a strain point where it tears itself apart (It shrieks when under too much strain.). Well it won't fly, especially if one of the strap-ons cuts out.

Your R-6 is not designed well, as of now. Put some distance (a staging brace or collar between the payload faring and strap-ons and you may be all right. And use four, not three strap-ons. The R-7 works for good reasons.

[HMS Sophia]

Do you know what harmonic air flow around a cylinder is, and what happens when boundary flow is rolled at mid-cylinder? The cylinder will snap in two in the direction of strain. Like breaking a twig in two.

Yes I do.but you've done nothing but insist it will occur while thoroughly misunderstanding the design. Here:

Put some distance (a staging brace or collar between the payload faring and strap-ons and you may be all right.

There is ten metres of fuselage between the tip of the boosters and the nose cone fairing. I'm certain there is plenty of space, considering its the same spacing as on the r-7.

Well it won't fly, especially if one of the strap-ons cuts out.

Neither could the R-7. It didn't have engine out capability. The ninth flight of Luna 8K72 is a good example of this. Of course, the Luna also had resonant vibration issues because of the newly added upper stage as well, so...

And use four, not three strap-ons. The R-7 works for good reasons.

I'm simply not so sure you're right. Though it would make for interesting plot to have them have to switch to four because of issues that three creates. Its not like things like that never happened IRL.

[Judah14]

FYI the R-6 did exist as a design study which eventually led to the R-7.

[HMS Sophia]

FYI the R-6 did exist as a design study which eventually led to the R-7.

It did. In fact there were a variety of designs for it.
But I'm writing an AU, so I just use similar designation systems rather than actual rockets

[Tobius]

Not enough distance, and if you think about it, you will know why. Air flow unstuck produces turbulence over the length of the cylinder.

From the citation Judah 14 helpfully provided (thank you, sir.):

Following the February 1953 decree, OKB-1 superseded the N-3 study with a development project code-named T-1, from "Tema" (theme) No. 1. Reflecting the expansion of the work on the ballistic missile, several new departments were formed within OKB-1 to focus on the task. To meet the required specifications, the intercontinental rocket was expected to have a launch mass of 170 tons. (52) For comparison, the largest existing Soviet ballistic missile at the time -- the R-5 -- weighed just under 29 tons! Thus, the proposed new rocket represented a major technological leap.

From the outset, the intercontinental missile was conceived as a two-stage rocket because it was the only practical way to achieve the required flight range. However, the ignition of the second stage during flight presented a serious technical obstacle at the time. After considering up to 60 designs during 1953, engineers chose a "parallel" architecture, clustering short boosters of the first stage around a much taller core booster. (18) Some called it a one-and-a-half-stage rocket, because all five boosters would ignite on the pad, but the second stage (also known as a sustainer stage) would continue firing, after the four boosters of the first stage had separated.

The R-6 used FOUR wrap-around strap-ons and a core sustainer. The reason was that if one strap-on one more strap-on actually could be dead-manned and the fuel pumped through the three working to still balance the thrust line along the CG of the mass. If the core failed then you use the four strap-ons. If the core and a strap-on failed, you could still use two engines to throw it downrange instead of having an H-bomb land on top of you. (Where did you get the idea that Russian liquid fuelled war rockets did not have engine out? The people didn't want their own hydrogen bombs falling on their own territory.) The R-6 you drew shows three, not four strap-ons. If one fails, the rocket tilts as uneven thrust shoves it into an uncontrolled loop. You have no way to balance the thrust. Loss of rocket, loss of mission. So I suggest that it might be okay to redraw the R-6 (R-7) with a symmetric payload cover, or insert the staging ring and put a cluster of four strap-ons around the core engine. That would work. What you have now doesn't and it won't work. The Russians are not stupid. Real or AU.

[HMS Sophia]

*snip*

Hmm... okay. I'll look at switching to 4. I'm still unsure of the 'lengthening the core' part because, well, the seperation between boosters and fairing is exactly the same as on the R-7.
But the engine out part is a good point I wasn't thinking about properly. So thanks ^^

[Tobius]

Rockets as you might have seen them if the Russians had been serious space explorers. Or it could have been the Americans. Either nation could have built something like that series given van Karman or Korolev could have gotten sufficient funding.

The Russians actually tried something a bit larger called the N-13 (or the moon rocket or the N-2 depending on which source you read), but they never could solve the plumbing arrangements for their main engine cluster. A problem that was that seems to have recently plagued Falcon 9 from Space-X. The cause as always is defective parts from second rate manufacturers. The Russians had no one to blame but themselves for their defective injectors and valves. Space-X bought turbine pumps from China. They should have stayed 100% US.

[HMS Sophia]

Great rockets Tobius. I might have to look at your shading for my own shortly.
Speaking of which:

I ended up going for a two booster arrangement on the R-6. I didn't want to do a straight copy of the R-7, but as you pointed out, the 3 core is imbalanced in regards to thrust. So there it is. Now with added Verniers.
The Aggregat got classic V-2 style fins and carbon vanes (yes, the mounting is different, but such is life).

[Tobius]

You cannot launch rockets or have an ambitious space program without understanding the tinker-toy erector set logic behind any viable space program---> especially a primitive one.

One of the things you do not do is erect a stack sideways and raise it from horizontal to vertical. That guarantees a failure on the pad. Neither do you move it loaded.

[Judah14]

So why then Russian, SpaceX and Orbital ATK rockets use horizontal assembly if it just results to pad failures? They use it because it allows for simpler launch pad designs, in SpaceX's and OrbATK's cases, the transporter-erector doubles as the umbilical connection tower.