yeah, i was in doubt about 'little by little' as it's quite a specific situation and the language is very accurate and there can be no unnecessary words. It's better to say 'carefully' instead.

i also translated it as close to the original sense as possible and my English looks a bit awkward in some places.

This is what i don't understand: Carefully Bop-Up .

what is 'bop up'?

this part about 'getting higher over the hill' was really difficult to translate. In Russian it's 'потихонечку будешь подниматься' and it means 'get the aircraft higher, raise it' but i could find the apt English word (which obviously must be short). 'Bop up' looks good. Is it kind of military slang?