In some examples, this disclosure describes a system for verifying identities of a first user and a second user. In some examples, the system includes processing circuitry and a memory device configured to store biometric verification data associated with the first user and the second user. In some examples, the system also includes an input device configured to receive biometric input data and transmit the biometric input data to the processing circuitry. In some examples, the processing circuitry is configured to determine whether the biometric input data matches biometric verification data for the first user or the second user, unlock the aircraft in response to determining that the biometric input data matches biometric verification data for the first user or the second user, and activate the aircraft for operation in response to determining that the biometric input data matches biometric verification data for the first user.