One in a series of posts about an aeronautical engineering course I created this year.
The aim of this project was to explore the concept of longitudinal equilibrium (“trim”) in flight, and the ways in which it can or cannot be attained in practice. The lecture far exceeds what is required to solve the problem and indulges into a discussion of the design choices, pilot technique, and human interaction facets of the topic. The result of the interaction of two passionate close friends, the session was the most successful of the course.
The lecture was one of two parts. My objective was to explore trim thoroughly in this session before diving into longitudinal stability in the following, eighth and final session. It was a wise proposition and I think the distinction between the two concepts —which both are affected by the same parameters— really came through.
The session starred long‐time friend and airline pilot Hamassala David Dicko. We prepared the lecture and project together over three days1, and shared the session.
David focused on the topic of trim from the point of view of the pilot (as we found out, pilots and engineers do not even define trim in the same way!), explaining how things are felt and accounted for in the cockpit. It was a fantastic contribution, culminating in a discussion about the human/machine interaction implications of the trim management automation on airliners.
I also learned a lot from David by seeing him interacting with the students in a way I had not thought was possible. This prompted very interesting discussions afterwards and I think I will improve greatly in this regard.
The part I took charge of is a very basic quantitative introduction to trim. The equations are certainly intimidating, and I took care in class to focus us all on the important parts only. Despite the minor caveats2 things went well.
The project is not exactly brilliant — to me it is more of a riddle than a true learning framework. Given the time invested in the preparation for the lecture, the length of the in‐class session, and the context within the course (this was the seventh week and sixth deadline day in a row), I think this can be forgiven. I will try to re‐mold it entirely this year.
Overall, not even withstanding the sheer joy of working with my good friend, the session was the highlight of the course and a success by almost any metric, including the most important of all, student motivation and enjoyment. I am looking forward to inviting David again =)
- Some frisbee throwing might or might not have been involved there [↩]
- I am dis‐satisfied with the way the final, coefficient‐form trim equation is expressed, since it relies on the overall aircraft lift coefficient rather than the wing lift coefficient. In fine, aircraft stall will be determined by the latter, which is really the relevant data here. [↩]