The extreme engineering of aircraft windows
Few companies have the technology to make aircraft windows which are getting harder to make.

In late May, a chemical storage tank with more than 7,000 gallons of toxic material began heating up – fast. The tank belonged to GKN Aerospace, a company that supplies parts to the aviation industry, including aircraft windows.
As the temperature inside the shiny metal storage vessel rose, workers realised they had a problem. The tank was at risk of exploding, potentially showering nearby neighbourhoods with methyl methacrylate (MMA), a skin and lung-irritating, external compound used in plastics production.
The tank's temperature reached 100F (38C) – though possibly went higher - 100F was simply the maximum reading, external on the temperature gauge inside.
To find out what goes into the making of an aircraft window, I spoke to Jean-Eric Vermont, general manager of French company Saint-Gobain Aerospace.