Blockchain for aircraft maintenance. Early this month, it was reported that an airplane going from Addis Ababa to Nairobi crashed shortly after takeoff. All 157 persons on board perished. Few months before this fatal crash, precisely late October last year, a similar crash occurred. A flight from Jakarta to Pangkai crashed into the sea 13 minutes after takeoff, killing all 189 people on board-May their souls rest in peace (Amen). Flight security is very paramount and can therefore not be overemphasized. The blockchain can provide details on the entire life cycle of an aircraft component from the producers, distributors, installer, and operators. Once a part has been made, the manufacturer would make the new blockchain. Other participants which are nodes can then add blocks to the chain. When an airline company purchases an aircraft, they can verify where each parts of the aircraft comes from, confirm its life cycle and also update the flight hours each component undergoes. Aircraft maintenance records can also be made secured and transparent. The blockchain would have a record of when a fault occurred, the facility manager (engineer) or company who made the required maintenance of which must be authorized and the replaced components if any. Frauds that can occur through the installation of non-official aircraft parts are eliminated since each component source can be verifiable and maintenance records are immutable on the blockchain. The overall state of an aircraft can be made available and verifiable by a passenger that wants to board. One can therefore make the decision to board or cancel flight.