Rolls-Royce Conway
...that the Rolls-Royce Conway, a turbofan engine, was the first commercial aero engine to be awarded clearance to operate for periods up to 10,000 hours between major overhauls?
...that the <b id="mwFFc"><a href="./Rolls-Royce_Conway" id="mwFFg" rel="mw:WikiLink" title="Rolls-Royce Conway">Rolls-Royce Conway</a></b>, a <a class="mw-redirect" href="./Turbofan_engine" id="mwFFk" rel="mw:WikiLink" title="Turbofan engine">turbofan engine</a>,  was the first commercial aero engine to be awarded clearance to operate for periods up to 10,000 hours between major overhauls?