Random Musings from the Warped Minds of Jonathan Goff, Ken Murphy, John Hare, and Kirk Sorensen
Posted in Rocket Design Theory, Technology on Jan 29th, 2013
In many discussions of rocket technology, a skeptic will often make some comment about how things would be so much better if we had Warp Drive. But the reality is that we don’t really need Warp Drive for things to be interesting. We just need Sufficiently Advanced Propulsion Technology™ (name derived from Clarke’s Third Law). [...]
Posted in Rocket Design Theory on Jun 10th, 2010
A few months ago, I spent some time describing some calculations of payload fraction that I derived to assist in the design of rocket vehicles. My motivation for getting into this type of work came about from my work on the X-33 rocket when I was an intern at the Skunk Works. I wondered how [...]
Posted in Rocket Design Theory on Mar 1st, 2010
When I was learning how to use mass-estimating relationships (MERs) at Georgia Tech, our focus was on reusable launch vehicles, and most of our MERs came from NASA Langley, where my professor had once worked. When it came to much of the reusability aspects of the spacecraft, the MER tended to depend on the entry [...]
Posted in Rocket Design Theory on Feb 27th, 2010
Continuing with our story from last time… The next day, your boss pokes his head in your office and asks: “How’s those forty trans-Mars injection stages going?” He notices that you’re checking out scuba-dive sites in the Caribbean for your upcoming vacation with your feet up on the desk, and comes into the room with [...]
Posted in Rocket Design Theory on Feb 25th, 2010
Now that I’ve gotten the math and derivations out of the way, let’s us the payload fraction expressions in a real-world example. Let’s say you work for the chief technologist of NASA, and he’s thinking about sending humans to Mars. He’s considering whether or not to invest in a seemingly-promising new technology: nuclear thermal propulsion. [...]
Posted in Rocket Design Theory on Feb 24th, 2010
In the last post, I attempted to calculate a basic expression for the propellant-mass-sensitive term (lambda) and in this one I will attempt to do the same thing for the gross-mass-sensitive term (phi). In so doing, I will hopefully be able to show how a number of key factors in the rocket design affect the [...]
Posted in Rocket Design Theory on Feb 23rd, 2010
In my last two posts I’ve been talking about calculating payload fraction of a rocket using the mass ratio from the rocket equation and some vehicle parameters that have been sensitive to propellant mass and gross mass. To use these parameters successfully, it would be helpful to have some idea what they should be for [...]
Posted in Rocket Design Theory on Feb 22nd, 2010
As I prepared for this post tonight, I realized that I wasn’t really modifying the rocket equation at all–I have been using the rocket equation and a summation of mass terms to find the payload fraction, which I consider an especially useful value to know. Furthermore, if you read my previous post, you probably figured [...]
Posted in Rocket Design Theory on Feb 21st, 2010
When I was an undergrad, I spent two summers interning on the X-33 program at the Lockheed Martin Skunk Works in Palmdale, California. It was a fantastic experience and I got to meet with and work with some wonderful people on a very exciting program. Plus I got to live in the Mojave for two [...]