What is it that keeps us awake at night? A new study from the German Aerospace Center on sleep patterns showed that unpredictable noises are the most disturbing to our sleep patterns. Noises like an airplane taking off have a more gradual rise and fall in sound despite lasting longer than the passing of a car. And yet in sleep surveys, people report aircraft noise as disturbing their sleep. The study’s authors speculated this was because a typical sleep cycle lasts 20 minutes and so airplane noise was most likely to be remembered. However what they actually found was car and rail noise interrupted normal sleep patterns.
It’s no surprise people would complain about aircraft noise, it’s a constant nuisance for people who live near military airfields and commercial airports. A lot of work goes into reducing the noise airplanes make. When new airports are built or existing ones are expanded much of the public concern is over noise, traffic and how it will impact their lives.
People often ask what use it is spending a lot of money on NASA and its associated space programs. But NASA is so much more than the shuttle program or the Kepler Mission. Constantly it works with industry to develop the future of aviation, and often at any extremely low cost design model where the designs improve current products with the government not actually receiving any reward.
One of these outcomes is the chevron design on the nozzles of jet engines. NASA helped develop the technology of using these sawtooth notches on both the nozzles and nacelles of jet engines to reduce overall noise of the engine. The research was largely spearheaded by engineers at NASA but then actual implementation arrived from a partnership of NASA with industry. You can see the engine itself branded from several companies but that photo is a GE jet engine on a Boeing aircraft. This chevron design is expected to be implemented on Boeing’s new 787s.
So next time you awake angrily at the sound of an airplane consider the cars are actually keeping you up at night and thank NASA as well as many other government funded research laboratories for much of the technology that helps us all sleep better at night.
Basner M, Müller U, & Elmenhorst EM (2011). Single and combined effects of air, road, and rail traffic noise on sleep and recuperation. Sleep, 34 (1), 11-23 PMID: 21203365