Superconducting technology for aerospace application is enabled by emerging development around hydrogen cooled electrically powered aircraft, aiming at zero-emission aviation. Superconductors, typically in the form of tape or wire in a composite architecture, can not only carry current density which is over 100 times that of copper and aluminium, but are also characterized by much lower losses. This property of superconductors makes them good candidates for the fabrication of superconducting devices of high specific power density, i.e. lower size and lighter weight, which is critical for aerospace applications. Superconductors, like any other conductors, require standard insulation to function safely and reliably in the electrical apparatus of aircraft, especially due to the special architecture, operating temperature, and operating condition of superconducting apparatus at high altitude. Extra attention should be drawn to choose proper insulating materials for such applications. In this paper, the challenges and considerations for choosing insulating materials for superconducting devices in cryo-electrified aircraft are reviewed and discussed.