Confidence is high. I repeat, confidence is high.

Date: 1954-06-13

Amidst news that the Soviets may be developing an Intercontinental Ballistic Missile (ICBM), their so-called "R7" project, we have been tasked with producing a rocket capable of reaching from Western Europe to Moscow.

The objective is simple in its audacity: Increase our rocket's capabilities from 600km downrange to over 3,000km, creating an Intermediate-Range Ballistic Missile (IRBM) before the two superpowers.

We have a range of new technological innovations on our side:

  • We have developed a newer, lighter, aluminium alloy for our rockets.
  • We have improved our existing main rocket engines (on par with the Russian RD-102).
  • We have improved our avionics to the point we can control our rocket launches.
  • We have also developed a new upper stage rocket engine similar to the US AJ10-27 engines, which use nitric acid/aniline and are the latest generation of the SR-1 engines we flew right back in 1951.
Historical Aside: The Russian RD-102 was never actually developed having being surpassed by the engine which was later designated the RD-103, the last of the Russian V-2 variants. The AJ10 series went on to be developed to suit many purposes. It was used on the Apollo Service Module and the Space Shuttle. In fact, it's still in use in the next-generation of capsules, with the AJ10 being the main propulsion engine of the Orion Spacecraft, NASA's new crewed vehicle that will be going back to the Moon and, eventually, Mars.

Combining these we also need to take account of a new limitation: Our current launch pad can only support a 20 tonne rocket. To maximise our capabilities we will need to use every bit of that 20 tonnes, while minimising the weight of our payload.

Presenting the SR-2d, coming in at 19,906kg:


The SR-2d has a guided lower stage which carries an unguided upper stage that has 3 of our new engines:


The upper stage is deployed using small, quick-fire, solid fuel kick-boosters which not only solves the ullage problem for the engines but also spin stabilises the stage: 



The most fragile bit of the rocket is the new upper stage engines. These engines are, as of yet, untested. If any of the engines fails, the rocket will very likely fail to meet its objective. They are, however, required, since the engines are only rated for 52 seconds and there is more than 52 seconds of fuel to go through (3x as much, to be exact!). The extra thrust also minimises the opportunity for gravity to take hold, improving overall efficiency.

Current testing is, however, showing positive results. I estimate a roughly 70% chance of success. For our test flight we'll be yeeting it across the Nile Delta in Egypt, over 3,000km to the east, where it will burn up on re-entry in to the atmosphere.

Next Post: Onwards and sidewards


Comments

Post a Comment

Popular posts from this blog

Not every rocket's a winner

Image
My initial concept for the SR-2b was to adding staging to the rocket design to be able to get more distance out of it and perform sub-orbital re-entry tests: This design certainly fit the bill in some respects. On a good day it could achieve a height of 250km, double what we'd managed previously. Having similar fuel tanks and engines reduces the tooling cost significantly. It also had no issues around recovery of the payload vehicle (a biological sample)... when it worked. Despite these plus points, I ran in to a major issue with the design. Notice how severely tilted the wing fins are; this was the level of spin stabilisation required to achieve the needed level of spin to keep it going straight. Precession is a natural consequence that comes with spin stabilisation . If the spinning of the rocket is too strong, a large degree of precession occurs. Precession is best demonstrated with a spinning-top example: Source: http://hyperphysics.phy-astr.gsu.edu/hbase/top.html As our leve
Read more

The big one: Getting to orbit

Image
The time has come to build our first orbit-capable rocket and design a payload for it. Woden Main Stage At the core of our new design is a new engine, similar to the RD-107 rocket engine used as the main engine on the Soviet's R-7 rocket . It can achieve a specific impulse (ISP, which roughly equates to efficiency) of 255 in atmosphere and offers a whopping 820 kN of thrust, far in excess of anything our space program has worked with before. Despite this, it's conceptually pretty similar to the V-2 rocket engine, only swapping out the ethanol for the more efficient kerosene . Woden Engines We are currently constructing a new launch pad capable of shifting 60 tonnes (three times our previous mass). Easily growing to match our new facilities, our new rocket core weighs a whopping 58 tonnes by itself. We have full avionic control and can control it using the built-in vernier engines . This design is intended to be modular, growing to meet the needs of our orbital programme mov
Read more