UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 6-K REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE SECURITIES EXCHANGE ACT OF 1934 For the month of August, 2004 SPIRENT plc _____________________________________________________________________ (Translation of registrant's name into English) Spirent House, Crawley Business Quarter, Fleming Way, Crawley, West Sussex RH10 9QL, UK. _____________________________________________________________________ (Address of principal executive offices) Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F. Form 20-F X Form 40-F..... Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934. Yes ..... No X If "Yes" is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82- ________ 834 - 16 August 2004 SPIRENT PLC Sale of Aerospace software Business Spirent plc (LSE: SPT; NYSE: SPM), a leading communications technology company, announces that it has sold its aerospace maintenance, repair and overhaul software business (MRO) from within its Systems group for a cash consideration of $5.35 million (approximately GBP2.9 million). MRO, with operations in San Diego, California and Yeovil, Somerset, is a supplier of ground-based logistics support and maintenance, repair and overhaul software systems for the civil and military aviation markets. In the year to 31 December 2003, MRO had sales of GBP8.7 million. The net proceeds of the sale will be used to pre-pay $5.0 million (GBP2.7 million) of Spirent's senior notes. After the application of the net sale proceeds Spirent will have $124.8 million (GBP68.6 million) of notes outstanding. Anders Gustafsson, Chief Executive, said: "MRO has an established position in its market and should have every opportunity to move forward under its new ownership. The sale of MRO is the last in the series of strategic divestments of our aerospace businesses." - ends - Enquiries Anders Gustafsson, Chief Executive Spirent plc +44 (0)1293 767676 Eric Hutchinson, Finance Director Investor Relations Catherine Nash Spirent plc +44 (0)1293 767676 Media Jon Coles/Rupert Young Brunswick +44 (0)20 7404 5959 About Spirent Spirent is a leading communications technology company focused on delivering innovative systems and services to meet the needs of customers worldwide. We are a global provider of performance analysis and service assurance solutions that enable the development and deployment of next-generation networking technologies such as broadband services, Internet telephony, 3G wireless and web applications and security testing. Our Network Products business is a developer and manufacturer of innovative solutions for fastening, identification, protection and connectivity in electrical and communications networks marketed under the global brand HellermannTyton. The Systems group comprises PG Drives Technology which develops power control systems for specialist electrical vehicles in the mobility and industrial markets. Further information about Spirent plc can be found at www.spirent.com Spirent Ordinary shares are traded on the London Stock Exchange (ticker: SPT) and on the New York Stock Exchange (ticker: SPM; CUSIP number: 84856M209) in the form of American Depositary Shares (ADS), represented by American Depositary Receipts, with one ADS representing four Ordinary shares. Spirent and the Spirent logo are trademarks or registered trademarks of Spirent plc. All other trademarks or registered trademarks mentioned herein are held by their respective companies. All rights reserved. This press release may contain forward-looking statements that are based on current expectations or beliefs, as well as assumptions about future events. By their nature, forward-looking statements are inherently predictive, speculative and involve risk and uncertainty because they relate to events and depend on circumstances that will occur in the future. You should not place undue reliance on these forward-looking statements, which are not a guarantee of future performance and are subject to factors that could cause our actual results to differ materially from those expressed or implied by these statements. These risks include the risks described from time to time in Spirent plc's Securities and Exchange Commission periodic reports and filings. The Company undertakes no obligation to update any forward-looking statements contained in this press release, whether as a result of new information, future events or otherwise. Signatures Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. ______LUKE THOMAS______ (Registrant) Date 16 August 2004 By ____/s/ Luke Thomas____ (Signature)*