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AIAA Team Aircraft Design Competition 2009-2010

Introductory Lectures on Aerospace Design Oct. 16th, 2009

University of Southern California

Sina Golshany


Lecture-1 Aircraft Design Methodology & Management with Remarks on Historic Backgrounds


Aircraft Design Methodology

– Methodology: • A set of flexible guidelines and methods to reach at an objective which is creative in nature. Usually intended for cases were multiple correct answers exist. (i.e. a flexible doctrine) • Generally, it may include: – Methods for tasking & logical Analysis of a problem (i.e. sensitivity to change in a particular variable) – Methods to formulate (define variables) for the problem – Methods to identify critical design variables – Methods to solve for the critical design variables – Methods to make this all work simultaneously – Methods to get the most optimum solution for all critical variables simultaneously.


Aircraft Design Generalities – It highly depends on the directions chosen by the premier designer. – Lead designers often modify basic textbook design methodologies to emphasize a certain aspect of a configuration or achieve a particular quality in their design. – The process of design, is considered highly repetitive – Alternative concepts are explored quite rigorously – Many describe the process as a marathon – Feedback cycles & their role in optimizing a selected configuration – Multiple correct answers to one problem DO exists. – Devil lies in the details


Multiple correct answers to the same question: – YF-16 & YF-17 Projects


Multiple correct answers to the same question: – YF-16 & YF-17 Projects – Same requirements – Same competition – Two significantly different answers

-Both work great -Both ended in designs that went into service


The Devil is in the Details!

- The VFX RFP response ran to a massive 37 volume proposal occupying 54 binders and a real size prototype. - First flight was achieved in almost 2 years (July’68-Dec’70) - They sure got something to smile about!


The Devil is in the Details!

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Douglass Design Facility in El-Segundo Almost all are capable draftsman as well as engineers Lithographic techniques for drafting Mechanical computers (YF-12 Project Utilization)


A Brief History of Lead Designers & Their Chosen Methodology


Clarence “Kelly” Johnson

(1910-1990) Lockheed Martin Corporation Skunk Works Division, Lockheed Commercial Airplane

– First Director of Skunk Works – Arguably the most successful designer of all times. – Some of the most controversial and successful aircrafts ever. – Multiple Collier Trophy Winner.


Clarence “Kelly” Johnson

(1910-1990) Lockheed Martin Corporation Skunk Works Division, Lockheed Commercial Airplane


Clarence Kelly Johnson

(1910-1990) Lockheed Martin Corporation Skunk Works Division, Lockheed Commercial Airplane

– Be quick, be quite, be on-time. – Believed in aircraft performance obtained at a great cost. – Believed in creative solutions Could not bare the ideas of next generation (Ben Rich and F-117) – His 14 (or 15) Rules of Project Management – Highly Individualistic Designer: – ‘The number of people having any connection with the project must be restricted in an almost vicious manner. Use a small number of good people (10% to 25% compared to the so-called normal systems)’


Clarence Kelly Johnson

(1910-1990) Lockheed Martin Corporation Skunk Work Division, Lockheed Commercial Airplane

– Appreciated esthetic value of aircrafts as a sales strategy (Lockheed Constellation as an example)


Ben R. Rich

(1925-1995) Lockheed Martin Corporation Skunk Works Division, Lockheed Commercial Airplane

– Graduated from UC Berkley – specializing in both: "aeronautical engineering and dating sorority girls!“ – Second Director of Skunk Works (Father of Stealth technology) – Directed the F-117, F-22 , and many still classified projects – Argued to have been involved with project Aurora (?) ->


Ben R. Rich

(1925-1995) Lockheed Martin Corporation Skunk Works Division, Lockheed Commercial Airplane


Edward Henry Heinemann

(1908-1991) Douglass Aircraft Corporation, later General Dynamics

– Self-trained chief designer – Went to Manual Arts high school in Los Angeles – Classmate with Jimmy Doolittle – Designed his first aircraft when he was 23 – Designed some of the most successful naval aircraft ever – Collier Trophy winner.


Edward Henry Heinemann

(1908-1991) Douglass Aircraft Corporation, later General Dynamics

-Heinemann’s Scooter, A-4 skyhawk (introduced 1954)


Edward Henry Heinemann

(1908-1991) Douglass Aircraft Corporation, later General Dynamics


Edward Henry Heinemann

(1908-1991) Douglass Aircraft Corporation, later General Dynamics

– Highly individualized (A-4 Skyhawk design over Christmas) – Highly focused on disciplines, but mostly regarding the ideas of a configuration teams: – ‘Respect the specialists -- those who are masters of a particular phase of an operation. But be wary of allowing them to make big decisions’ – ‘Avoid paralysis by analysis’ – Considerable consideration for power plant selection: – ‘Select the best engine, build your aircraft around it’ – Significant attention should be paid to weight engineering and weight optimization


European School of Aircraft Design – In contrast to Heinemann's way, it offers VERY complex solutions to aeronautical problems – Replacing creativity with complexity – It concentrates on individualist way too much (aimed at cutting development cost) – It commits too many mistakes during the development project, causing significant delays, and horrible cost increases – Products are often time over priced. – They take advantage of the limitations placed on sales to foreign nations by American aviation industry. – Pioneers often end working as consultants to U.S. design firms (Hans Ulrich Rudel & Fairchild Aircraft Company)


Predominant Methodologies in the U.S. – Roskam’s Methodology: Well defined & flexible


Hierarchical Elimination:


Management & Engineering Organization – Role & Significance in Multi Disciplinary Design


Intelligence & Competitive Analysis

-Open Source Intelligence -Competitive Analysis -Provides insight in to the direction of market & competitors -Methods of operation -It is a business practice, regardless of the field. -It is ethically justified


Management -What is the significance & role of a design management strategy? -It is usually done in teams to represent the elements of each influenced design discipline. -Questions to be answered by Management Specialists: -Task Orders & Schedules -Resource Allocation (Human & Financial) -Critical Issues to be Addressed: -Trade Studies (what to change?) (alternatives?) -Optimizations (what to optimize) -Planning & Tracking Tasks -Optimization of task’s breakdown & their interactions with each other (DSM as an example)


Design Structure Matrix (DSM) – Developed partly by Dr. Steven D. Eppinger from MIT Sloan School of Management. – Among many other contributors back in the 70’s. – Created in response to industry needs. – Used heavily by the industry. – It is recently introduced in the field of Aircraft Design. – It is shown to reduce the development time and cost.


Design Structure Matrix (DSM) – Publically available case studies – All have shown improvement in the development cycle


Different Development Stages:

– RTD Phasing Chart. – We will be dealing with T and mostly D phases.


IDEF Flow Charts – DSM is used as an information exchange model, as an alternative to IDEF flow charts:


Design Structure Matrix (DSM) – Basis for defining the DSM matrix:


Grouping and tearing in (DSM) – To enhance the cooperation between teams/disciplines: – Breaking teams to sub-teams is good practice, as long as it doesn’t lead to something unmanageable:

– Can be combined with numerical algorithms . . . – More on PSM-32 later.


Notes on DSM: – Size of the Design Structure Matrix defines the level of details to be looked at as independent disciplines. – This means an oversized DSM can be exceedingly hard to manage in reality and a too small DSM can’t encapsulate all the required tasks and disciplines for a project. – No easy, rigorous way of selecting the DSM size – Done based on experiment, and multi disciplinary knowledge – Roles for successes: – Case studies mater a great deal – General knowledge about aircraft design methodology matters even more.


Case Study-1:

Boeing Integrated Defense Systems, UAV Development


Case Study-2: Aquila VLJ trainer DSM strategy


Case Study-3:

Tranquillus 150 Pax midsize jetliner


Request for Proposal 2009-2010 • “Advanced, Environmentally Compatible Commercial Transport to use alternative fuels” -162 passengers (dual class) -Range: US transcontinental -Significant improvements in fuel burn (with associated CO2 reduction). -Use of alternative fuels, potentially bio fuels -No particular Noise Requirements -Improved passenger comfort -Reduced DOC and acquirement costs


Questions?


Tasks for today:

1-Constructing a DSM for our project 2-Constructing a Gant schedule for the project


Task:

1-Constructing a DSM for our project

Using the PSM32 software Based on 2008-2009 DSM


Task:

2-Constructing a Gant Schedule

Using Microsoft Visio provided the items in the DSM


Thank You !

1 - Management and Aircraft Design Methodology  
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