Instrument landing system (ILS), radio navigational equipment that guides aircraft to the runway in low visibility.

ILS requires aviation authority certification and licences; ship as engineered systems with documentation. Radio, broadcast and surveillance equipment needs destination radio licensing and type approval (WPC, CE-RED, FCC), correct frequency bands, anti-static and shock-resistant packaging, export control and end-use checks for transmitters, radar and imaging, and serial or IMEI lists on the invoice.