A man convicted of two charges under the Terrorism Act has lost an appeal against conviction but seen his sentence cut at the Court of Appeal.
Rowe was found with instructions on how to fire a mortar
Andrew Rowe, 36, a Muslim convert from west London, was found guilty in September 2005 of having instructions on firing a mortar and a secret code.
A 15-year term of imprisonment was reduced to 10 years.
Rowe was described at his trial as a "paid operative" who had travelled the world for the cause of fundamentalism.
He was arrested in the summer of 2003 at the French end of the Channel Tunnel on his way back to the UK.
He was jailed for seven-and-a-half years on each charge of possessing the items for terrorism purposes, the terms to run consecutively.
The Lord Chief Justice, Lord Phillips. sitting with four other judges, ruled the sentence in total was "too high" and reduced the penalty for possessing the mortar notes to two-and-a-half years.
It was the prosecution case that Rowe was planning an act of terrorism at the time of his arrest.
The Old Bailey heard the secret code substituted words such as police, target and weapons for mobile phone model numbers.
It was said to have been devised to allow Rowe to include information about his operations within an seemingly innocent message.
The court heard he had travelled extensively after converting to Islam at the age of 19.
Police said the countries he visited, the people he met and the methods he used to avoid detection had the hallmarks of an al-Qaeda operative.
Rowe, from Maida Vale, said he was involved in bringing humanitarian aid to Muslims exposed to unlawful violence in Bosnia and Chechnya.