Generally, Omnicharge power banks are allowed on airplanes. Individual airline requirements may vary, but the standard across most airlines is that for up to 100Wh there aren't any restrictions. Between 100Wh-150Wh you need airline approval, which mostly just means you need to fill out a form at check-in, and you can take up to two devices with you. See theAmerican Airlines guidelinesas an example. (Click the batteries section.)