Preliminary Sizing of FAR Part 23 and Part 25 Aircraft
Autor: Joeri Heinemann
Datum: 12.07.2012
Master Thesis
Abstract
This thesis covers the subject of preliminary sizing together with the development of the SAS
Optimizations tool for Part 23 and Part 25 certification requirements. Preliminiary sizing is a
very important step in the process of designing an airplane as it decides if the airplane will be
further developed or not. The design of an airplane is defined by different specifications and requirements
that can follow from a mission specification or market research, etc. The goal of preiminary
sizing is translating these requirements and specifications into design and performance
parameters. Most of these requirements and specifications are defined by certification requirements.
Therefore Part 23, Part 25 and CS-VLA have been analysed to see which requirements
affect the design. In order to translate these requirements and specifications to performance parameters,
the mechanics behind each flight phase have to be analysed. With these equations resulting
from these mechanics, a tool is developed that allows students to perform preliminary
sizing by use of a set of input parameters and then perform an optimization on this design for a
chosen design goal. In order to build the tool for Part 25, OPerA was dismantled and deconstructed
to a more simple version that could perform the optimization by using the algorithms
used in OPerA. After this a more detailed Oswald Factor calculation was implemented. This
tool could now be used to build a tool for Part 23 as well by making the necessary changes according
to the certification requirements. With the tool finished, it was decided to write a general
users guide to SAS Optimization.