1 - Implying the pilot is dumb enough to pass withing a few feet of the dragon.
2 - Cats have claws, so they have a natural immunity to cutting? No. This isn't pokemon you dipstuff.
3 - Last I checked, not a lot of dogfights happen in mountains. And above them it's not even up for debate. The dragon is literally sitting up there with its' pants down. It has zero chance of winning a high altitude engagement.
4 - One hit from the plane, and the dragon most likely loses the ability to fly
1 - a plane can't hover or move backwards, once it moves towards the dragon the only way you can avoid it is turning, which gives the dragon the chance to catch up and rip the backside. Turning also nullifies the ability to shoot the dragon. So generally, the plane will lose, if it loses the first round of shooting. Which on boths sides, is a matter of luck, and age.
2 -
From the dragon myths I read. The same scales on the inside that protect from fire are in layers on the outside.
3 - No, but it depends if the plane is going to get the dragon. Or the dragon going to get the plane. If the plane attacks the dragon. The dragon has home advantage. Of the mountains. If the dragon attacks the plane, the plane has home advantage.
4 - An opinion, not a fact.
Everything has their own view on dragons.
Percisely.