The aircraft took off from runway 20 at 13:33 and departed on the 218-degree radial. The pilot informed ATC that he would be operating not above 500 feet and changed frequency to Marine Channel 12. The aircraft flew along the River Itchen to that part of Southampton Water between the towns of Netley and Hythe. The ‘Pre-Landing (Water)’ checklist was completed. Among other things, this requires the pilot to confirm that the floats are extended, the landing gear is retracted and the nose landing gear doors are closed with the amber ‘Nosewheel Doors Closed’ light illuminated. Having circled the area once, the pilot flew a left hand circuit and approach on a heading of about 280ø; the aircraft lightly skimmed the water surface and took off again. A second approach was made with the aircraft still configured for a touch-and-go landing. The crew reported that the touchdown was normal and the aircraft had been settled on the water for several seconds when the pilot noticed a boat wake ahead. Immediately thereafter water entered the cockpit and cabin as the Catalina yawed violently to the left. CONCLUSION: “Because the nosegear doors were not recovered, it is not possible to exclude the possibility that the aircraft encountered a significant piece of flotsam which caused the doors to collapse inwards. Regardless of this, the presence of the severe corrosion in the nosegear operating mechanism torque tube can only have served to compromise the ability of the left door to resist the range of loads which might have been imposed during a water landing. The corrosion found in the torque tube had clearly developed over a long time but it went undetected because it was inside a closed area and no specific inspection of the inside of the tubes was called for. When looking at another Catalina, it was observed that there were no bungs in the aft ends of the torque tubes and it would have been possible, with suitable apparatus, to inspect the whole of the inside of the tube assemblies, particularly in the zone where the tube failed on this occasion. The Maintenance Manual and Schedule for the Catalina were developed and written in a different age when these aircraft were very differently utilised. Although both the Manual and Schedule have been developed as a result of the Catalina’s continued amphibious operation, for probably much longer than originally envisaged, there are now likely to be some time related maintenance considerations which did not previously exist.”