# Why hasn’t the challenges slide about ceramic engines been updated since 2015? # Why hasn’t the challenges slide about ceramic engines been updated since 2015 Between [[gradyFullyNonMetallicGas2015a]] and [[Advanced CMCs, Additive Manufacturing, and Joining/Integration Technologies]]? <!-- #questions --> [Web URL for this note](http://notes.benjaminreinhardt.com/Why+hasn’t+the+challenges+slide+about+ceramic+engines+been+updated+since+2015) [Comment on this note](http://via.hypothes.is/http://notes.benjaminreinhardt.com/Why+hasn’t+the+challenges+slide+about+ceramic+engines+been+updated+since+2015) <!-- {BearID:D80731F8-5D9E-4259-900F-9933E249BAC4-19569-0003CC83E8A67170} -->