兄弟とも「妻と飛行機の両方は養えない」との理由で、生涯独身を通した。

「」、。

Both brothers remained single their entire lives, saying they 'couldn't support both a wife and an airplane.'

Literal

Brothers [both-とも] 'wife [and-と] airplane [attributive-の] both [topic-は] cannot-support' [quotative-との] reason [with-で], lifetime bachelor [object-を] maintained-[past].

A famous quote about the Wright brothers. とも ('both, all') attached to a noun expresses totality. 養う ('to support, to provide for, to raise') is the formal verb for financial/care-giving support. ~との ('with X as' attributive) combines the quotative と + の for 'the reason of X.' 生涯独身を通す ('maintain lifelong bachelorhood') is a set phrase.