Background Orbital fractures are common injuries found in facial trauma. Typical etiologies of orbital fractures include motor vehicle collisions and assault. We report the case of a 32-year-old male who suffered an orbital fracture from a water balloon. Additionally, we describe the aeromedical complications that may result from this injury. Finally, we attempt to answer the question of when a patient may return to flying after sustaining such an injury through review of the literature. Case presentation A 32-year-old male pilot with the United States Air Force was at an outdoor event with his unit when he was struck with a water balloon launched from a sling shot into his left orbit. Shortly afterwards, he had an onset of subcutaneous emphysema and was escorted to a nearby Emergency Department. Computed tomography identified an orbital fracture with associated orbital and subcutaneous emphysema. The patient was evaluated by a plastic surgeon and was determined not to be a surgical candidate. Four weeks later, he returned to flying status. Conclusions Water balloons are thought to be safe and harmless toys. However, when coupled with slingshots, water balloons can become formidable projectiles capable of significant orbital injury including orbital fractures. These injuries are concerning to aviators, as the most common sites for fractures of the orbit are the thin ethmoid and maxillary bones adjacent to the sinuses. At altitude, gases in the sinuses may expand and enter the orbit through these fractures, which may suddenly incapacitate the flyer. It is important for flight surgeons to identify and assess these individuals to determine suitability for flying.