Part 4 of “Aspects of Aircraft Design and Control”

Lec­ture 4 — Cruise performance
Project 4 — The mar­ket for winglets

This project’s objec­tives were to explore the notions of and rela­tions between cruise speed, fuel con­sump­tion, weight, and eco­nom­ics. The lec­ture focus­es on ordi­nary flight mechanics.

This is a very short and light­weight lec­ture: we focus on a sim­ple mod­el for the rela­tion between lift and drag, and we derive the Breguet Range equa­tion in class (first part of the projet).
Once this is cov­ered, the project lets stu­dents explore air­line eco­nom­ics by them­selves, con­cep­tu­al­iz­ing, esti­mat­ing and research­ing val­ues for sec­tor length, air­craft usage, and so on. My feel­ing is that they tru­ly enjoyed this.

Over­all the lec­ture and project are far less demand­ing than any of the three pre­vi­ous ses­sions, a very dras­tic step down. This was prompt­ed by the cor­rec­tion of the Project 2 hand-ins in the week lead­ing to this lec­ture, which as I dis­cussed ear­li­er unam­bigu­ous­ly showed that I had been aim­ing too high.

Prepa­ra­tion for this lec­ture was thus impro­vised in a cou­ple of days (I recy­cled the pay­load-range dia­grams from anoth­er course). In ret­ro­spect, reduc­ing the dif­fi­cul­ty of the lec­ture and project was a wise idea. There was decid­ed­ly more enjoy­ment among the stu­dent groups, in class, in the reports and presentations.
At the start of the lec­ture I bet crois­sants and cof­fee with stu­dents that they would find that project much eas­i­er. No-one ever claimed any­thing but I didn’t get any cof­fee, either.