Great Lakes is a 121 passenger airline with 19 seat Beechcraft 1900s and 30 seat Embraer 120s. They are also a 135 cargo carrier and fly Beechcraft 1900s on those routes. I have never heard of anyone flying a single engine airplane for them (outside of an intern ferrying a mechanic...they used to have a Duke, Baron, and something else in SPW). You really need to do some homework before you send a resume into them. A good place to start would be their website. You can even do the online application from their website.