Revealing the secret of sonic booms

Christine Darden 1942-present

At the dawn of the infamous Space Race between the US and the USSR, which began in 1955, NASA employed a swarm of ‘human computers’ to calculate flight trajectories, propulsion and rocket dynamics. One of these human computers was Christine Darden, who joined the ranks in 1967. Eight years later Darden sought to apply her mathematical skills to the field of engineering and secured a position at NASA’S Langley Research Center as one of a handful of female engineers. Unbeknownst to Darden, her first assignment would be a groundbreaking one. Sent to work on a project to study sonic boom minimisation, the rollout of modern computers directed Darden to expand her mathematical abilities to design computer programs to calculate the effects of sonic booms. While working on the project full time, Darden also found the time to undergo doctoral courses in mathematical and engineering science at George Washington University in Virginia. For her dissertation she combined her work at NASA to explore the environmental impacts of supersonic transport (SST). When an object such as a plane travels at such a high speed it creates waves of pressurised air, heard on the ground as a sonic boom. These booms can be so violent that they can cause damage to structures below and even shatter glass. In an attempt to evaluate the risks associated with SST, teams of NASA scientists replicated the booms using wind tunnels, while Darden took to her computer to develop a computer program to calculate the effects of the booms. Comparing Darden’s data and model experiments, the two produced the same outcomes, although Darden’s method proved cheaper and more efficient than building a model simulation. Unfortunately NASA discontinued the SST project, but Darden’s work didn’t go to waste. Seeing the potential applications for military aircraft development, Darden completed her sonic boom research, graduating with her engineering doctoral degree in 1983.