Their collapse creates shock waves that shoot very small jets of water onto the surface being cleaned. (sciencenewsforstudents.org)
As more and more flights were canceled with the downturn in the economy, airlines brought in smaller jets. (creditcards.com)
Just last month, American Airlines was forced to cancel dozens of flights from Phoenix when temperatures of nearly 120 degrees made it too hot for smaller jets to take off. (cnbc.com)