There’s No Place Like Homing Device…Invention of the CPI Radio Beacon in Carleton Place, Ontario

Did you know there’s a historic Carleton Place connection with Air Force One? It all goes back to one of the area’s high-tech giants, Leigh Instruments Ltd., which was established in the town in the early 1960s and became renowned for its high-quality tech products. One of its claims to fame was the production of the aviation-changing crash position indicator, which was a predecessor of the black box. The CPI is a radio beacon designed to be ejected from an aircraft so that it survives a crash to broadcast a homing signal to rescuers.

The concept was developed in the 1940s and ’50s, with production eventually being contracted to Leigh Instruments. Canadian and American air force aircraft – including Air Force One – were equipped with CPI, and by the 1970s it became a standard item on many aircraft, making Leigh Instruments one of the largest Canadian electronics firms until 1990.

There are also connections between the company’s original investors and one of the town’s early industrial families – the Findlays – bringing old and new technology together.

Contact the Carleton Place and Beckwith Heritage Museum at 613-253-7013 or