The boat, operated by global marine cable installation firm A-2-Sea, is equipped with the latest technology, including a multi-beam echosounder and side-scan sonar, which can detect anomalies on the seabed.
The vessel, which travelled from Southampton, is to be used by the group being led by world-renowned shipwreck hunter David Mearns.
In a tweet, Mr Mearns, who claims to have found 24 major shipwrecks, said the boat, called Morven, was brought to Guernsey six hours earlier than scheduled to take advantage of a break in the weather.
The group expects to start scanning the seabed on Sunday.
The plane carrying the new Cardiff City signing and pilot David Ibbotson vanished as it passed near Alderney on 21 January during a flight from Nantes in Brittany to the Welsh capital.
On Wednesday the Air Accidents Investigation Branch said that two seat cushions, believed to be from the single-engine Piper Malibu, had been found on the Normandy coast. They said they had now identified a four-square-nautical-mile priority search area, and would work alongside the private search group, which has been funded through an online campaign.
