Guest column by Peter (‘Purps’) Greenfield — We were young, full of testosterone and living the dream. The year was 1976 and I was selected to fly the McDonnell Douglas A4-G Skyhawk fighter off the RMAS Melbourne, Australia’s only aircraft carrier. All of us had flown the CAC Aermacchi MB-326H jet trainer, known affectionately as the ‘Macchi’…