Suicide by pilot is an aviation event in which a pilot deliberately crashes or attempts to crash an aircraft as a suicide act, with or without the intention of causing harm to passengers on board or people on the ground. If others are killed, it may be considered a type of murder–suicide. It is suspected to have been a possible cause in several commercial flight crashes and has been confirmed as the cause in other instances. Determining the motives of pilots can be challenging for crash investigators, as pilots may intentionally disable recording devices or engage in other actions to impede future investigations. Consequently, definitively proving pilot suicide can be difficult.

A murder–suicide is an act where an individual intentionally kills one or more people before or while killing themselves. The combination of murder and suicide can take various forms:Suicide after or during murder inflicted on others Murder that entails suicide, such as suicide bombing or the deliberate crash of a vehicle carrying the perpetrator and others Murder of an officer or bystander during the act of suicide by cop Suicide after murder to escape criminal punishment(s) Suicide after murder as a form of self-punishment due to guilt Suicide before or after murder by proxy Murder linked with a person with suicidal ideation Joint suicide in the form of killing the other with consent, and then killing oneself Suicide by pilot