ClearJet just raised a $25 million Series B , led by Edison Partners, to expand a company that flies packages on spare space aboard passenger planes. Shipping had become his second-biggest cost, and one carrier dropped his account with five days’ notice. Instead, it books unused cargo room on flights that are already crossing the country, then hands parcels to final-mile carriers at the other end. The company says it can cut shipping costs by up to 35% while shaving one to three days off delivery. airports and connects retailers with major airlines and several delivery providers.