|Your manager should actually make an appointment for a course in introductory management. It is acceptable for busy managers to require appointments. However, the most important part of setting appointments is to actually keep them, and this is where your manager's skills are rather thin.
In addition to meeting with the employees on this formal basis, effective managers today are spending a good deal of time meeting with their employees on an informal basis. By being available, accessible, and visible on a regular basis, managers do not need as many formal meetings with the employees.
Your manager does not realize that he is actually the one who loses by canceling appointments. His avoidance strategy ultimately leads to delays and errors. It is also a source of frustration and dissatisfaction for the staff.
The next time you set an appointment with him, try to let him see how he and the department can profit from this meeting, while also letting him know about the costly outcomes if the meeting is cancelled. You should also guarantee that the meeting will be short, perhaps 15 minutes or less. If he still balks and your work takes a dive, he cannot say that you did not sound the alarm.