Modern aerospace systems are marvels of engineering. Their amazing achievements are due in large part to software, yet relatively few project personnel, especially project management staff, understand or appreciate the significance of it. The lack of understanding and attention to software often dooms large aerospace projects to significant delay if not outright failure. As a motivation, several software-related aerospace incidents, from benign to calamitous, are recounted here to demonstrate the extent of the problem. Frequently repeated oversights witnessed on many large aerospace projects are then reviewed, with an eye toward what can (and should) be done to avoid the pitfalls. The intent is to empower the reader with information and ideas to prevent software from slaying the giant systems that it is built to support. Nomenclature t = time