Final answer:
Using nonapproved cleaning compounds on aircraft can lead to corrosion, material degradation, and negative reactions with the aircraft's surfaces and components, posing safety hazards.
Step-by-step explanation:
A primary reason why ordinary or otherwise nonapproved cleaning compounds should not be used when washing aircraft is because their use can result in corrosion, degradation of materials, and unintended reactions with the aircraft's surface and components. For example, detergents containing phosphates and industrial-strength cleaners with quaternary ammonium compounds can damage the aircraft structure.
Similarly, glass cleaners containing alcohols and ammonia, acidic cleaning agents with strong mineral acids, or bleaches containing reactive chemicals can harm the sensitive materials used in aircraft construction.
In addition, cleaners like drain cleaners which are strongly corrosive or acidic, pose a danger not only to the aircraft but also to personnel due to their hazardous nature leading to injuries or health damage. Furthermore, the use of nonapproved cleaners may interfere with the functional integrity of crucial systems, such as fire extinguisher systems and could compromise safety.
Therefore, it is imperative that only approved cleaners, designed specifically for use on aircraft, are employed to ensure both the safety of the aircraft and those working on them.