Complex sentence: In 1912, Abramovich built his own aircraft, now known as the Abramovich Flyer, based on what he had learned at the Wright factory, and flew it to Saint Petersburg, Russia to participate in a military aircraft competition.
Split into simpler sentences: In 1912, Abramovich built his own aircraft, the Abramovich Flyer, based on what he had learned at the Wright factory. He flew it to Saint Petersburg, Russia to participate in a military aircraft competition.