That pic of the sub-floor between the deck and the skin reminded me of an issue I was involved in when serving in 75 Squadron RAAF in Butterworth Malaysia.
The squadron had approx 12 single seat fighters and two twin seat (tandem) trainers, nicknamed "The Duals".
View attachment 1297187
Pilots had consistently complained about one of the trainers having "shit handling". Eventually, after a couple of write-ups of "Rapid Uncommanded Pitch Manoeuvres" the aircraft was hangared and put on jack for a full inspection.
I had to safe and remove all of the crew ejection systems (canopy/seats etc).
While crouching in the fwd cockpit I noticed a lot of moisture/condensation toward the rudder pedals and told the engineering supervisor.
To cut a long story short, a couple of holes were drilled in the skin at the lowest point of the cockpit floor and over 200 litres of rainwater was drained from the sub-floor. It seemed a drastic solution, but at a forward airbase without the facilities to do a complete fwd fuselage disassembly it was the only solution. I think the aircraft was flown back to Australia for a full remedial servicing.
It was concluded that canopy rain covers had blown off in a monsoon one Friday evening after the squadron secured and two days of rain took their toll.
While the Mirage IIIO was a bitch to work on, they were and impressive and beautiful aircraft to see in the sky. It was basically and engine with wings, and a tiny spot for a driver.
View attachment 1297193
Click to expand...