Boeing Co. agreed to sell its flight navigation unit and other digital assets to Thoma Bravo for $10.6 billion in cash, the first major portfolio transaction under Chief Executive Officer Kelly Ortberg as he seeks to shore up the planemaker’s finances.

The deal, with the private equity firm Thoma Bravo, will help the struggling aerospace manufacturer pay down debt and streamline its operations.

Chicago private-equity firm Thoma Bravo is spending $10.55 billion in cash to buy several digital aviation assets from Boeing, including Jeppesen, a well-known maker of maps and navigation charts.