When you are sitting in a plane at thirty thousand feet, you want to know that the wings are solid. Modern planes aren't just made of simple aluminum anymore. They are made of complex layers called composites. These materials are light and strong, but they are also hard to inspect. You can't just look for a dent. Sometimes the layers inside start to pull apart, but the outside looks perfect. This is where Probeinsight comes to the rescue. It is a specialized way of listening to these parts to make sure they are still healthy. It is a very quiet, very precise science that happens in labs long before a plane ever takes off.
The scientists working in this field use something called resonant ultrasonic spectroscopy. That sounds like a mouthful, doesn't it? But it is actually a simple idea. Every object has a natural ring to it. If you hit a wine glass with a spoon, it makes a specific note. If the glass has a crack, that note changes to a dull thud. Probeinsight does this with airplane parts, but it uses sounds so high that humans can't hear them. They
