When the Russian officers are taking pictures aboard the Cayuga, a flag is visible. It is either the international maritime flag signal X ("stop carrying out your intentions and watch for my signals") or the Finnish flag. If it is indeed the Finnish flag, it is an obvious error. If it is the letter X it is merely curious.
When LT Bud Roberts and Harm are on a Russian ship, Bud (who is a lawyer) is wearing the leather naval flight jacket. The only officers authorized to wear it are qualified current and former Naval Aviatiors, Naval Flight Officers, and Flight Surgeons.
The USS Cayuga was a Landing Ship Tank (LST-1186) commissioned 8 Aug 1970 and decommissioned 26 Aug 1994. She is now owned by Brazil - Disposed of through the Security Assistance Program (SAP), transferred, Foreign Assistance Act (FAA) Section 516. Information from Naval Vessels Register site, Department of Defense.