So finally if it's happens ,the manual input gesr down door closes accidentally, there'S no way but to landing on the belly? Or again open again the door and pull the manual gauges for extend gears, they'll go down again and locked and can landing with the 3 gears right down locked?
Yes, correct if the door closes at 1500 feet like in the video; if you bounce on the runway and it closes during the first touchdown... You crash the plane. The same applies at 50 feet; with the inertia, you will do a touch and go on a 'Gear in transit.' Chances are slim, but we also used to say, 'What are the chances of losing two engines on takeoff!