The Very Spring and Root

An engineer's adventures in education (and other musings).

This content shows Simple View


Color for Dollars


From Karagiozis et al 2011


I didn’t work on this specifically, but this was the nature of my previous job. A humorous aspect was the fluid nature of the acronym CFD… formally it stands for Computational Fluid Dynamics, but others that captured the often tricky business of interpreting the results included Colorful Fluid Dynamics, Color For Dollars, Contours For Debate, and my personal favorite, Can’t Fucking Decide.


A little over a week ago, NASA’s Curiosity rover landed on Mars, the culmination of years of engineering. The mission’s landing, in particular, was the subject of intense scrutiny as Curiosity’s size necessitated some new techniques in the final segments of the landing sequence. As it hit the Martian atmosphere at 13,000 mph, the compression of the carbon dioxide behind the capsule’s shock wave slowed the descent.  At roughly 1,000 mph—speeds still large enough to be supersonic—Curiosity deployed its parachute. Shown above are the parachute in numerical simulation (from Karagiozis et al. 2011), wind tunnel testing at NASA Ames, and during descent thanks to the Mars Reconnaissance Orbiter. The simulation shows contours of streamwise velocity at different configurations; note the bow shock off the capsule and the additional shocks off the parachute. These help generate the drag needed to slow the capsule. For an interesting behind-the-scenes look at the wind tunnel testing for Curiosity’s parachute check out JPL’s fourpart video series. Congratulations to all the scientists and engineers who’ve made the rover a success. We look forward to your discoveries! (Photo credits: K. Karagiozis et al., NASA JPL, NASA MRO)

Best feedback from a supervisor ever. Written on a Subway napkin after a two-hour lunch meeting with the agency Chief Scientist, in which we were trying to pitch our ideas for future flight projects. My boss? Yeah, so, she’s awesome like that.

“Toward More Bird-Like Flight: Thinking Outside the Box”

A great TEDxNASA talk by someone I’m proud to call my friend and colleague. Al’s talk speaks for itself, so I won’t bother summarizing it here. However, I will add that the ideas in this talk have led to one of the most innovative and exciting things going on at NASA Dryden right now, and I’m not even sure its an official project.

A team of engineers, designers, and machinists, as well as some incoming students from the NASA Aeronautics Academy, are actually going to be building and flying two Horten wing gliders as research-instrumented RPVs here in the high desert. The PDR was yesterday, and what I saw was a design that is smart, lean, and suitable for rapid prototyping.

Al’s approach to project management is Antoine de St. Exupery’s quote personified:

Quand tu veux construire un bateau, ne commence pas par rassembler du bois, couper des planches et distribuer du travail, mais reveille au sein des hommes le desir de la mer grande et large.

(If you want to build a ship, don’t drum up the men to gather wood, divide the work and give orders. Instead, teach them to yearn for the vast and endless sea.)

It works. Everyone in that room is inspired; rather than needing to be pushed to work, most have to be pulled back from going too crazy. Decisions are enabled at the lowest level that makes sense, and ideas emerge and mesh at the front lines. This is no small matter either… applying these ideas to wing and propulsion design lead to massive practical fuel savings for the whole aviation industry, and Dryden might be the first to push this envelope and grab some flight data. 

At a time when NASA is being criticized for being a lumbering bureaucracy well past it’s prime, it’s so refreshing to see that grassroots and groundbreaking projects can organically form and even thrive at Dryden when the right people are given enough free rein.

You can read Al Bowers’ own perspective on his blog post for Dryden.