There's no denying that Stratasys (SSYS -0.20%) is an excellent 3-D printing company. However, the company is missing out on a massive opportunity because it lacks the ability to 3-D print with metals. As a result, it isn't benefiting from the 3-D printing aviation boom that's currently under way.

Aviation giants like General Electric and Rolls Royce are investing in 3-D metal printing to manufacture jet engine parts that save on weight and therefore improve fuel efficiency. In fact, GE will be investing "tens of millions" toward improving its 3-D printing supply chain in the coming years to ensure that 3-D printing can handle the level of scale it needs.

Although the expectation is that Stratasys will eventually make an entrance into the metal printing space through an acquisition as well as a homegrown solution, until it does, it could be missing out big time on establishing valuable aviation customers. In the following video, 3-D printing analyst Steve Heller weighs into the discussion about what it could mean for current Stratasys investors in the context of an acquisition.