Do a research paper centered around retractable gear aircraft systems, including mechanical systems for both operating and preventing gear-up landings, safety concerns, common problems experienced.

Research paper centered around retractable gear aircraft systems, including mechanical systems for both operating and preventing gear-up landings, safety concerns, common problems experienced, a review of inadvertent gear up landing accidents/incidents, and the psychological aspects of preventing gear-up landings.

The paper should address the various lessons learned from previous such incidents, and address what measures (procedural, technological, etc.) should be adopted to prevent similar incidents from occurring in the future.