what is the second Tom Clancy splinter cell book.?

Answer 1

This is Splinter Cell: Operation Barracuda


From-
http://en.wikipedia.org/wiki/Tom_Clancy%27s_Splinter_Cell:_Operation_Barracuda

Tom Clancy's Splinter Cell: Operation Barracuda is a 2005 novel in the Splinter Cell series and a sequel to the 2004 novel Tom Clancy's Splinter Cell. Both novels were written by Raymond Benson under the pseudonym David Michaels. This is the final Splinter Cell novel to be written by Benson. The book was released on November 1, 2005 and was successful, reaching number 9 on the NY Times mass market paperback best-seller list.

Operation Barracuda, like its precursor, is told in the first-person from the view of NSA black-ops agent Sam Fisher.

Answer 2

The first two were written by Raymond Benson, under the pseudonym of David Michaels. It's not known who wrote the third one. Tom Clancy approved the series, that's all, and made sure that the technology and events in them were as realistic as possible.