Telos (TLS) 8-K Departure of Directors or Principal Officers

Exhibit 17.5

Thomas L. Owsley

1709 North 22^nd Court

Arlington, VA 22209

August 16, 2006

VIA FACSIMILE 703-729-7372

Therese Hathaway, Esq.

Corporate Secretary

Telos Corporation

19886 Ashburn Road

Ashburn, VA 20147

Dear Ms. Hathaway.

I am writing to inform Telos Corporation that I hereby resign from the Telos Corporation board of directors, effective immediately.

Sincerely,

Thomas L. Owsley

cc: Geoffrey B. Baker

David Borland

Norman P. Byers

Robert J. Marino

Langhorne A. Motley

Malcolm M. B. Sterrett

Bruce J. Stewart

John B. Wood