To ask the Secretary of State for Defence what estimate he has made (a) of the initial acquisition cost and (b) the through-life cost of (i) the Helix mission system and (ii) the aircraft which will carry the mission system. (260675)

The acquisition and through life costs of the three options being considered (the Nimrod R1 and the Nimrod MRA4 platforms with a bespoke mission system and the US Rivet Joint system) to meet the Helix requirement are being assessed as part of the preparations for a main investment decision expected in 2009.

To ask the Secretary of State for Defence when the successor aircraft to the Nimrod R1 is planned to achieve full operational capability; and whether the R1 and its successor aircraft are planned to operate in tandem pending full operational capability of the successor aircraft. (260676)

Key dates for a successor to the Nimrod R1 system and any necessary transition arrangements between the two will be agreed at the main investment decision point which is expected in 2009.