Updates with details from release throughout

By Milana Vinn

April 22 (Reuters) - Boeing BA.N said on Tuesday it would sell portions of its Digital Aviation Solutions business, including navigation unit Jeppesen, to private equity firm Thoma Bravo for $10.55 billion.

The U.S. planemaker will retain the core digital capabilities from the business that harness aircraft and fleet-specific data to provide commercial and defense customers with fleet maintenance, diagnostics and repair services.

The sale is a part of CEO Kelly Ortberg's plan to reduce Boeing's debt pile by offloading non-core assets.

Jeppesen attracted interest from private equity firms and at least one aerospace supplier, with final bids valuing it at more than $8 billion.

Thoma Bravo won the Jeppesen auction, edging out rival buyout firms such as TPG, Advent, and Veritas, according to four sources, who requested anonymity as the matters are confidential.

Boeing, which acquired Jeppesen for $1.5 billion in 2000, had aimed for a price above $6 billion when it launched the auction last year, but strong interest from potential buyers drove the valuation higher.

Englewood, Colorado-based Jeppesen is seen as a sought-after asset that could boost aerospace contractors and private equity firms, which typically like to buy businesses to generate steady cash flow.

About 3,900 employees work in Boeing's Digital Aviation Solutions. The transaction is expected to close by the end of 2025.

Boeing is set to report first-quarter results on Wednesday.

(Reporting by Nilutpal Timsina and Nathan Gomes, Anirban Sen and Milana Vinn in New York; Editing by Mrigank Dhaniwala and Arun Koyyur)

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