No surprises above-truth , I became a FO on the L1011 at the age of 24 and at 27 on the B747-400. On the L1011 I had a friend of mine who became a capt at a age of 27/8 and 3 year later capt on B747-300. We had a lot of funny looks from the pax´s and ground crew if we were flying together. Is just the way they say: beeing on the right place on the right time. And I tell you that the concept age vs airplane only works in the US, and to be quite honest with you, i think is wrong.
Happy landings