aviation's early days, bad weather could making landings
especially treacherous. NIST's greatest contribution
to aviation was probably the invention of the first
visual type radio beacon for an instrument landing system.
The system used strategically placed transmitters to
send radio signals to a plane's cockpit, allowing the
pilot to know his approximate position in three dimensions.
The technology enabled the first entirely radio-controlled
blind landing in 1931 in College Park, MD.