Designing a very light jet

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Akademin för Innovation, Design och Teknik

GadShannan DESIGN

Designing a Very Light Jet

Master thesis work

30 credits, D-level

Product and process development, concurrent engineering Master Thesis Programme Innovation and Product Design

Per Nyblom

Report code: IDPPOPEXD:08:11

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Abstract

Introduction

Very light jet is a hot subject growing stronger and stronger. The new type of air craft is an air plane that weighs less than 10000 pounds and uses a jet engine.

Problem

The student was proposed to designing a conceptual very light jet that could be used for inspiration and accepted the challenge.

Method

In this thesis the reader can follow the project progress in detail, the proposed methods and the results. The student divided the project into four activities analysis, creation, development and documentation.

Result

The project ended with a concept very light jet with simple specifications. Illustrations for inspirational usage and a simulation testing for verification of the proposed concept specifications.

Keywords:

Nm 1 nautical miles = 1.852 kilometres lb 1 pound = 0.45359237 kilograms ft 1 foot = 0.3048 metres

in 1 inch = 0.025 metres MTOW Maximum take-off weight

Pax Available Seats in an airplane both crew and traveller VLJ (micro jet) Very Light Jet, coined expression.

FAA Federal Aviation Administration, www.faa.gov EASA European Aviation Safety Agency, www.easa.eu.int CAA Civil Aviation Authority

PDF File format standard

Intelligence Information that is presented easy to act on. Thrust Power given by a jet engine measured in pounds.

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Acknowledgements

Thanks to GadShaanan DESIGN, the commissioner Mr Mladen Barbaric who has provided with this project and who made all of this possible, Colleges Minku and Damien who also contributed a lot. Thanks to Ragnar Tengstrand for his guidance. Thanks to Joe Kingham for his help in simulations, William E. Herp CEO of Linear Jet, Fazackerley Steve at CAA. Also thanks to the four girls on Barcley Street who all contributed in supporting my willpower to succeed.

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1. Introduction

There is an increasing demand and coverage on VLJ’s so called very light jets. One the most searched words on Google the online search engine during 2007, had been reported to be “VLJ” according to Design Director Mr Mladen at GadShaanan DESIGN.

About VLJ’s

A VLJ is a jet plane that weighs less than 10'000 pounds certified for single pilot operations. (NBAA, 2008)

The coined expression differs from different sources but all they all agree that is a jet plane that weighs less than 10000 pounds. However some references claim that they have four to eight passenger seats some that they are supposed to cost less than 4$ million. FAA, EASA however does use the same expression because of their system of classifications.

VLJ’s have been proven useful for lowering operational costs and are able to travel on smaller airports. Thus competing in price, time and location with the larger scaled transportation air planes. The price of the new smaller jet air planes is giving smaller charter and air taxi companies a chance to own a jet plane. Today there are roughly a dozen VLJ’s in production all with their own competitive attributes trying to supply the demand on the market.

Most VLJ's are produced as a purpose of taxi jets or private jets. The aim of Taxi Jets is to sell a flight ticket at the price of a regular business class ticket on for example a jumbo jet, but with the service of a private jet. Most air craft’s today are shared between owners reducing cost, hanger price and optimising flight time.

The major difference in a VLJ and jumbo jet is that VLJ's are focused transferring a certain few persons and jumbo jets often as many as possible, reducing flight per person where the VLJ is designed to reduce price for the person that wishes to travel alone or with a small group of people and give the person faster and more accurate flight. When comparing VLJ's to small propeller planes in private or taxi sector they are not new. There is already an establishment where taxi air planes fly and operate, however with the low weight combined with the jet engine the time of flight is reduced significantly performing in some cases up to double the speed.

About GadShaanan DESIGN

The company had made an assessment that this was the kind of inspirational project they wanted to act on. GadShaanan DESIGN is a company developing various products from mobile phones to trains working in fields of industrial design, engineering prototyping and marketing. On arriving to the first meeting Mr Mladen (also named as the commissioner in this thesis) told me about the change of plans and expressed his view on the current VLJ's how they were lacking design and aesthetics, he wanted me to design a concept VLJ more up to date with the car industry something new and impressive.

Current VLJ's are made by hand if compared with the car industry that has big product lines and spits

out three new car roughly every two seconds. (Worldometer, 2008) Cessna delivered 45 Citation

Mustangs in 2007 which is currently the only certified VLJ operating in Europe.

The commissioner Mr Mladen then proposed that the new project would be to design a new VLJ that they could use for inspirational purpose in future projects. There were some future projects they were planning and this project could be used to give inspiration for one of them.

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Purpose of this thesis

The purpose of this thesis is to prove that the student is capable of comprehending and solving a problem statement in a scientific way. The thesis will explain the steps and the conclusions made along during the project of designing a VLJ for GadShaanan DESIGN, what went wrong, what succeeded and finally the result of this project.

2. Aim of project

After the first meeting both the student and the commissioner thought that the sky was the limit, the concept would become bigger than anything the student had done before, and from what they discussed it sounded almost impossible, almost.

”You ask, what is our aim? I can answer in one word: It is victory” (Sir Winston Churchill, 1940)

The aim of this project is, with the help of employees at GadShaanan DESIGN, in a scientific way design a concept VLJ that can be used as inspirational tool for further product

development. The project will also teach the student more about real work.

3. Project directives

GadShaanan DESIGN is the commissioner who wished for the project to be an inspiration project for further development within their company. Therefore the project had few starting directives.

Commissioners directives

Design a VLJ

Maintain regular contact and meetings

Access to two designers during CAD part of the project. Use their methods of development

Access to give directives on produced material Sketches

CAD

Rendering and illustration

Students directives

Besides the directives for the student there were also some directives made for the commissioner:

Supply relevant information regarding design Car industry and in-house design methods

CAD frames for such relevant parts as chairs and cars Finnish the concept before the 11 June

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4. Problem statement

The problems that have been solved during this project are stated in this part of the report which can later be followed up in chapter 8. The problem was to design a VLJ, this problem can be broken down into sub problems that later can be divided into even smaller problems. However due to the project limitations sub dividing problems too much have been restricted and global definitions has been required to have a full concept with balanced depth.

Project Specification

The project specification has been split into two parts to help identify project goals.

Technical requirements

Choosing the most appropriate methods for designing a very light jet. Using the chosen methods in a controlled and traceable way.

Designing a very light Jet

Weighing less than 10000 pounds Advanced Avionics

Transporting passengers Flying with jet engine

Inspirational requirements

Creating a concept that can give inspiration for other projects. Being attractive

■ Perception

■ Cognition

■ Anthropometry

■ Geometry and colour language

■ Ergonomics

Visualising the concept in realistic way

Due to the fact that the commissioner was interested in an inspirational concept with a high level aesthetics the project focused more on the visual aspect of the project specifications. ”Design presents brand values in visual form” (Prof. h.c. Peter Pfeiffer, Senior Vice President Design of Mercedes-Benz, Commerce Germany, 2006)

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5. Project limitations

Time and money

Due to the knowledge in this field of studies the student had a lot of information to take in a short period of time. Therefore the project limitation is first and foremost time where the student and the commissioner decided that the student would work until he went back to his homeland and this has been set to five months of project development. From the five months work the student has estimated the required time on each part to get the best results asked from the commissioner. This helped the student to not get overwhelmed with fulfilling the immense project of designing a conceptual VLJ air plane. Economically the student was provided with some material such as sketching tools, magazines from the commissioner and bought some on his own mostly for the sketching part of the project.

Analysis, creation and development

Producing a project management of the required quality, literature used was narrowed down to two books, The Mechanical Design process has been used for overall management,

Introduction to Private & Public Intelligence for structuring gathered information. Pilots handbook for aerodynamics and overall flying, Grunderna i numeriska metoder has been used for calculations. Several articles and documentations found on internet and databases have been used to get a better view regarding design and VLJ's customers, past, present and future. This is also due to the fact that VLJ’s is a very new product. Organisation sites such as FAA, CAA, EASA, aerospace producers have been a valuable asset. Information in databases has also been used to find articles regarding the subject such as consumer behaviour, car/empirical design and anthropometric. Software and hardware for this project are as followed OpenOffice, Pro Engineer, Adobe Photoshop and illustrator, X-plane, down to the hardware a laptop and some sketching tools.

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6. Theoretical background, solutions &

methods

The methods used for completing this project have been chosen together with the commissioner and from studies of literature. Where the aesthetic and product-feature methods were decided and provided from the commissioner and the overall design methods were picked by the student from the literature or created for this project. The list of the methods used are all following the order of the Gantt schedule, presented later in this thesis, to give an easy reference and

structure.

Analysis

This is the activity that creates the structure of the project. Defines the problem, defines what paths to take and how to reach the best results.

Project Planning

What Project planning is the process used to organizing planned actions, money and

resources within a project.

Why _{To easier plan where and when to do things also to define what actions is}

needed in order to solve the project problem.

How The list below show the structure used in this project to solve the problem statements of this project and is based on the project management from The mechanical Design process

1. Establish the problem 2. Plan how to solve it

3. Understand the problem and define methods 4. Generate alternative solutions

5. Evaluate solutions

6. Decide on acceptable solutions 7. Communicate results

(Ullman, 2003, p. 16)

When Early in the project when the problem is being defined a project planning that

suite the problem is defined and used. Project specification

What A list of requirements that needs to be fulfilled during the projects life cycle.

Why _{The list is created to use as a measurable goals also to know where to aim the}

project with this tool it is easier to see define the steps needed to reach these goals.

How _{List goals that the project needs to reach to succeed. (Ullman, 2003, p. 72)}

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Information gathering and reading

What _{Finding and reading relevant information useful for the project.}

Why Without knowing your problem you cannot solve it, finding information about your problem will help to solve it.

How _{This is done by collecting and reading relevant information the student will have}

to decide on his own what is relevant and what is not and what can be useful and not, all of the information that is regarded relevant should be handled with the method Intelligence.

When _{During the analysis.}

Intelligence

What Intelligence is information that you can act on.

Why _{This is to acquire information that can be useful and easy to use later during the}

project.

How Intelligence is often divided into 3 steps but depending on the amount of searches the first two steps often have to be looped.

1. First search, at this point you do not know anything about the subject or you know a lot. Find relevant information and establish a basic knowledge around the problem. All search words and search areas should be documented.

2. The second step will be to extract better search words or search areas from the first search. A quickly look at the result is often the only step that is needed to see if it could be what was searched. Sometimes

it is hard to know exactly what is searched there for it is important to always keep track of what linked where and where leads ends and why. The first two steps should then be iterated until the exact or good enough information gathered. (Solberg Soilen, 2005)

When _{This is done when the problem has been or during the definition of the problem.}

Figure 1 Results from searches, the blue shapes represent the first searches, the green and the second more structured and finally the stars are marked as intelligence material.

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Creation

This are the activities were the student collects and use intelligence in various methods. Customer analysis

What Finding out who the targeted customer is and what they want.

Why To define a targeted market, what the customer want and need.

How _{Finding information regarding who fly business, income age social status. After}

acquired information estimating their needs and attraction. 1. Specify the information needed

2. Determine the type of data-collection method to be used 3. determine the content of individual questions

4. Design the questions 5. Order the questions 6. Take Data

7. Reduce the data (Ullman, 2003, p. 121)

When Before trying to define the product.

Car analysis

What Finding reoccurring features in new and award winning car design and the

targeted consumer price range car.

Why _{Because the car industry is very advanced in design, focused target groups and}

mass production. This area becomes a good reference as getting an up-to-date look on what is seen interesting and will be a future reference in design.

How _{Looking at award winning car design to find repeated features, types of buttons,}

shapes, colours etc.

When Before the creation activity for the sketching part.

Competition benchmark

What _{Identify and evaluate the competition regarding VLJ's.}

Why Looking at the current market to get a good idea of the current competition there features and design.

How _{Making a comprehensive specification list of the current VLJ's. Evaluating their}

specifications and design. (Ullman, 2003, p. 129)

When This is done before the concept creation activity.

Expert analysis

What Contacting users, pilots, producers, taxi companies, service technicians and

sellers, retrieve information directly from persons involved with VLJ's.

Why _{This is done to get a better view of the market and specifications that might not}

show on the producer’s homepage, also giving ideas on VLJ's future where they might evolve.

How Questionnaires and other means of contact regarding users, producers,

manufacturers and sellers personal view and future thoughts around the subject VLJ. (Ullman, 2003, p. 122)

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The walk through

What _{To make a description of what a customer would experience with all the five}

senses using the concept, from first seeing to leaving the subject.

Why To pinpoint and find the important features required to fulfil the customer’s needs and expectations. This is method similar to a function diagram (see next method), however the walk through emphases more on emotions and

impressions. This can later be translated into specifications the user needs and desires.

How _{Imagining all the steps, impressions and actions that a user would experience}

and perform. From the introduction of where the subject is seen to the end when the user leaves the subject. The imagined thoughts are documented and

expressed without narrowing down exactly what solution is needed to solve it.

When Done early in the concept creation activity, after specifying the problem that

needs to be solved and when a good idea of what features and solutions the subject should give to the user. Method provided by the commissioner Function Diagram

What Method to define all the features needed in a product.

Why _{This is used as a reference for creating new or different ways of solving}

requirements on the air plane.

How By listing all the attributes that the product should do in verb + subject form. ( Stamatis, 2001, p. 55)

When _{During the creation activity of the project this is a valuable tool.} Mood board

What A table of images that gives a feeling of the

final product and that helps to give a direction for the sketching.

“Mood boards are often used by graphic designers to enable a person to illustrate visually the direction of style which they are pursuing. However, Mood boards can also be used to visually explain a certain style of writing, or an imaginary setting for

a storyline. In short, Mood boards are not limited to visual subjects, but serve as a visual tool to quickly inform others of the overall 'feel' (or 'flow') that a

designer is trying to achieve. Creating mood boards in a digital form may be easier and quicker, but physical objects often tend to have a higher impact on people.” (wikipedia, 2008)

Why _{The method is based on creating a feeling. The mood board gives an overall}

comprehension of what colours, shapes and impressions that should be expressed from the final product.

Why Cutting out images from magazines and newspapers that can represent

feelings and impressions that the solution should express.

Arranging the cut out images on the Paper Marché in different ways

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Figure 3 One of many results from the use of tracing

Gluing the images to the Paper Marché and using this Board as a

reference while sketching.

When Before starting to sketch on concepts.

Sketching

What Sketching as a method of making a selling concept.

Why Designing an innovative VLJ requires appealing aesthetics

How _{All of the information gathered and evaluated in the beginning of the creation}

activity is used here. Through different sketching method ideas and concepts are created in a creative and informative way.

When When the problem and the idea has been defined.

Tracing

What Improving existing sketches and concepts.

Why This is done to improve and strengthening an idea or a chosen concept also in order to make it more appealing for the consumer.

How There are two ways of doing this

Making a couple of first light lines then

filling in the line or combination of curves that looks best.

Using tracing paper to sketch over an old

sketch thus having premade guidelines for the basic shapes and the freedom to change where ever wanted.

When _{Multiple times during the sketching process, very useful to improve a chosen}

concept. Creative sketching

What _{Making several creative sketches of a subject.}

Why This is done in order to find new ideas. Widening the set of mind.

How _{• Free sketching: Sketch what comes to your mind.}

• Combination: Combining the subject with another subject and illustrating the combination. Combining two different images, for example a jet engine and a trout.

• Artistic sketching: Starting to draw some random lines and mixes of colours and building ideas from that.

When Early in the process, it should be done before using methods to find concepts or

ideas.

Mass production of ideas

What Multiple rough drawings of solutions and ideas.

Why The best ideas are never the first ideas, emptying your conscious will let get past the incremental ideas and produce the radical solutions. A great number of possible solutions help the innovation process.

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sketches of images and ideas that pops into the conscious. (Ullman, 2003, p. 138)

When This is done as the first stage of the drawing procedure.

“He who spends too much time developing a single concept realized only that concept”.

Developing concepts

What Increasing the output ideas on a certain area.

Why _{To get a better product depth insight and development of certain ideas.} How Expanding and improving current ideas using creative

tools like moodboard, function diagram, creative sketching and mass production.

When _{After choosing concepts.}

Evaluating concepts

What Evaluating and picking the best concept suited for continuing with.

Why _{The project specifications are to evaluate and produce the best suited concept}

for the commissioner.

How This is done by weighing the different concepts against each other with the Demand specification: Perception/Cognition Anthropometry Marketing Geometry Shape design Psychology (Rolf Lövgren, 2006)

When When a certain amount of concepts have been produced.

Choosing a final concept

What _{Choosing the best Concept for further development}

Why To have a clear idea of what solution is chosen, because after evaluating concept the best concept is then improved.

How _{Picking all the features ideas into a solid idea. Letting the commissioner be a}

part of choosing the final concept and choosing interior parts and specifications.

When When a certain number of concepts have been met.

Figure 4 How ideas branch into new ideas

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Development

This is the activity that took the chosen concept and created an interactive three dimensional model and extracting illustrations.

3D modelling

What _{Creating the concepts in a 3D dimensional environment.}

Why This is done in order to better illustrate and create a model for future development.

How _{Using the 3D CAD software called Pro Engineer Wildfire 2.0.}

When _{After the creation activity has been done.}

Relearning Pro Engineer

What Relearning the software Pro Engineer.

Why _{In order to utilize the most of the software. In more advanced context this was}

done to learn more about surfaces that was needed in the creation of this product.

How _{By doing some basic and advanced tutorials to get the feeling of the software.}

Also practising on making surfaces to understand the limitations and

possibilities of this specific feature. Learning how to use and configure useful short commands.

When _{This is done before attempting to make the 3D model.}

Correcting features and curves

What Redefining features, curves, shapes and sizes using prints.

Why _{Acquiring a smoother and better design concept.}

Displaying a better overview and ability see and improve what works and do not work in an aesthetic way. This was also used to give the commissioner a way to give inputs to the concept in an easy and comprehensive way.

How Printing the concept from three basic angles front, top and right views on large papers. Then sketching over them to find better curves.

When _{Before going into details of the model.}

Figure 5 Applying sketched improvements in the Pro Engineer CAD modeling

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Model Rendering

What Extracting images from the three dimensional model

Why In order to portray the three dimensional model as realistic as possible and to give an easy access inspirational tool.

How The rendering software used was the built in rendering program of Pro Engineer. The commissioner recommended a software called Bunk speed however the student was not able to gain access to this software. To acquire the best appearance settings were changed: lighting positioning, strength, colour, softness, background, perception and reflection was changed on and around the model. The extracted rendering are compared with a chosen background and then adjusted in the software this iterative gives the best results relevant to the students knowledge of the rendering part of the software.

When While finishing the concept.

Testing and flight simulation

What _{Using the simulation software plane to test the model and concept VLJ.}

X-plane is software used as a tool of learning for training pilots it is also used by companies and public people to create and test different existing and non existing air planes.

Why _{Get feedback on the produced concept for future development and to use as a}

reference to see if the concept was a successful or not in the design.

How Implementing the designed model and its specifications into the software X-plane running tests on the model and extracting performance specifications.

When After specifying all features and finished model.

(X-plane, 2008)

QFD

What A tool to evaluate and help specify requirements of concepts.

Why _{The use of this tool in this project has been to verify and compare the new}

concept with the current competition.

How The QFD lists the requirements from the different customers; it also lists the specifications that the products can perform in a measurable. The two lists are then compared to see what customer requirements can be or is related to product specifications thus making a link between customer needs and adjustable

performances. For example to go fast is strongly connected with the thrust of the plane.

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7. Applied solution procedures

Designing a VLJ, also referred to as a private business jet or micro jet. All have a common red thread, it is a jet plane that is very small, light and mainly for businessmen. The importance is to land the concept in the definition area at the same time not being exactly the same.

Analysis

The first things done in the project was to structure and analyse the problem and collect information needed to solve the problem. This was done by acquiring articles and public definitions regarding the subject, using the intelligence method (p. 11) to create information to act on. A definition of VLJ was defined. With this information the student could then evaluate the project limitations and make a project specification (p. 8). The project specification

changed the general definition “Designing a very light jet” to the current list of requirements. There is an abnormality in design process due to the fact that the commissioners requirement on a high aesthetic level. The project specification that states the wanted solutions and this was used to define what information, tools and required time / action would be needed and put in a Gantt (appendix 1.2). With the time schedule and the project specification the student could now in a scientific way follow the projects progress with a plan of action that could be

controlled with the project specification. Other specifications such as project limitations and a report structure was defined and has been followed up during the projects life time, all found earlier in this thesis.

The student then continued to search for actionable information read various books and articles on subjects such as product development, aerodynamics, aesthetics consumer behaviour, anthropometrics, car design. He also send out a survey to 60 different companies and persons, the questions we divided into three categories producer/seller/other, user/pilots/repairmen and experts (appendix 1.3). There were few responses. All this was done to try and get a good general perception of the product and task at hand.

Creation

The activities were the student used intelligence in various methods for creating the concept VLJ.

Competition benchmark

In the mechanical design process (Ullman, 2003) Ullman says that benchmarking (p. 13) should only be done in consideration to the customer and in the value of the customer. The student did this first because it would give him a good overview of the current competition and what the market was looking at when comparing and estimating advantages. When it comes to complex vehicles like air planes there are millions of things to take in consideration for the customer from how fast the Air plane flies to the colour of a button. The student compared the information that was accessible and of seemed to be of interest to the future customer. The benchmark made between the current VLJ (appendices 1.4), the student listed thirteen different air planes where one is not really meeting the requirements in weight but it was interesting in size and speed. The specifications are not always valued in consideration to the customer because the complexity of translating all specifications into user values and then converting them back would be too big. The results showed a medium of 40x40 feet sized air plane that had a cruise speed at 350 knots with 6 seats. This gave the student something to aim for and to

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use as a reference. From this he was also able to print some interesting graphs such as comparison between the different VLJ's in terms of weight / pax and weight /thrust. Defining the customer

The student started to define who the customer is (p. 12). The student sent out a questionnaire to almost 70 different companies/persons related to VLJ’s. The student received only one reply. However after a several tries he was able to define his search words well enough to find some relevant information.

“Top management was the largest group of passengers for six months during the year of 1997. (57 percent)

were top managers (Chairman, CEO, COO, CFO, Board Directors) or senior managers (Executive or

Senior Vice President). Middle managers (Vice President, General Manager, Director) and Technical, Sales, Service, Professional or Contract staff comprised just over one-fourth (26 percent) of those passengers, and 1 out of 10 passengers in the last six months was a customer. Passengers report spending nearly half (48 percent) of their time aboard company aircraft in work-related meetings, conferences, or discussions with other company employees or customers, compared with only 8 percent of time in these activities while aboard commercial aircraft.” Found in Louis Harris poll

(NBAA, 1997)

“UK business passengers using Heathrow had the highest average incomes at £79,000, compared with £67,000 at Gatwick and Luton Airports and £57,000 at Stansted. North of the border, average business incomes were lower, at £53,000 in Edinburgh and £50,000 at Aberdeen.” CAA Passenger Survey Report

(CAA, 2005)

From this information the student could verify what the commissioner had stated, that the targeted customer for a VLJ is in fact managers or higher. The student then combined this information between car design and the concept air plane, the commissioner wanted a jet plane more like a car. The analysis that the student made was comparing recent award winning cars over 30'000$ finding reoccurring design that could be used as guidelines for the aesthetics and features. Noted subjects such as dark colours and silver highlights was very common, buttons that was integrated with bright colours indicating easy use and where about.

Evaluating required amount of passengers

Chosen from gathered information, benchmarking and questionnaires, the student had to do a compromise with the commissioner who had stated that he wanted a “6-8 seater”.

The market showed a more usefulness with fewer seats:

“Average business jet load factor is just 2.3 passengers” Company co-founder of Blink, Peter Leiman (ainonline, 2008)

“National Aviation average passenger count for business flights has a passenger load factor is 3.9.” (NBAA, 1997)

William E. Herp, President and CEO of Linear Air told to the student during an interview with the student march 2008, that currently in a Cessna air plane that carries 8 persons has an

average of 3 persons per flight, and with their ordered Eclipse he estimates and average of 2 out of 6 seats will be filled.

The stated 6-8 seats were an estimation made by the commissioner. The research showed transportation for a smaller amount of passengers would the best solution therefore six seats were the best choice within the specified amount. One or two of these seats would be pilot seats.

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Interior specifications

Using simple knowledge in ergonomics and measurements from anth (Naval Biodynamics Laboratory, 1988)

during the sketching and 3D modelling process.

taken from current VLJ’s to be used as reference measurements. Interior from c was studied to use as feature and aesthetic guidelines.

General airplane specification

Choosing the engine is often done to match the specifications of the plane weight and size (Federal aviation Administration Washington DC

find a good starting point in size and thrust

information from competitors. A trend line would enable a good view of what an average size would need for a thrust. The spread area of length and width of each

and there thrust was plotted on a graph. The points on the graph defined a trend of around what thrust was needed for a certain size. Because the system was over defined the trend of how thrust and weight interacts for current VLJ is hard to say by looking Th

decided to use the least square method to define a linear line. With the matrix calculation and linear equation

straight line (appendix 1.5).

Illustration 1: Thrust/Area, Blue current VLJ's, Red Least Square calculation

With the line as a reference the student could now change size of the concept if needed and get a rough idea of the required thrust that this change would implicate.

The engine PW625F was chosen due to the small size and good thrust of 2,500 pounds. However later in the project this came to change due to large cabin space and simulation results. The fuel was chosen to 2'000 pounds estimated from the current VLJ D

same size and thrust.

From the first estimations the student found that D

similarities. The specifications gives us more information about the chosen size such as distances, which is up to 1300 nautical mile

(diamondaircraft, 2008). From the site FAA the student was able to find information regarding fuel storage. “Fuel is by regulations from FAA always stored in th

The student also had to meet the requirements of using advance

a glass cockpit. A glass cockpit is an aircraft cockpit that features electronic instrument Using simple knowledge in ergonomics and measurements from anthropometric sizes (Naval Biodynamics Laboratory, 1988) intelligence was extracted and later

during the sketching and 3D modelling process. Measurements of interior area were s to be used as reference measurements. Interior from c was studied to use as feature and aesthetic guidelines.

pecification

Choosing the engine is often done to match the specifications of the plane such as Federal aviation Administration Washington DC, 1980). In order t find a good starting point in size and thrust to work around the student used current information from competitors. A trend line would enable a good view of what an average size would need for a thrust. The spread area of length and width of each

there thrust was plotted on a graph. The points on the graph defined a trend of around what thrust was needed for a certain size. Because the system was over defined the trend of how thrust and weight interacts for current VLJ is hard to say by looking Therefore the student decided to use the least square method to define a linear line. With the matrix calculation

and linear equation the student calculated a

With the line as a reference the student could now change size of the concept if needed and get a rough idea of the required thrust that this change would implicate.

ngine PW625F was chosen due to the small size and good thrust of 2,500 pounds. However later in the project this came to change due to large cabin space and simulation results. The fuel was chosen to 2'000 pounds estimated from the current VLJ D

From the first estimations the student found that D-jet that was a good reference due to the similarities. The specifications gives us more information about the chosen size such as distances, which is up to 1300 nautical miles for D-jet on the amount of 1740 pounds of fuel.

From the site FAA the student was able to find information regarding “Fuel is by regulations from FAA always stored in the wings.”

The student also had to meet the requirements of using advanced avionics;

A glass cockpit is an aircraft cockpit that features electronic instrument ropometric sizes

later used Measurements of interior area were s to be used as reference measurements. Interior from cars

such as In order to the student used current information from competitors. A trend line would enable a good view of what an average size would need for a thrust. The spread area of length and width of each VLJ

there thrust was plotted on a graph. The points on the graph defined a trend of around what thrust was needed for a certain size. Because the system was over defined the trend of how

erefore the student decided to use the least square method to define a linear line. With the matrix calculation

dent calculated a

With the line as a reference the student could now change size of the concept if needed and get

ngine PW625F was chosen due to the small size and good thrust of 2,500 pounds. However later in the project this came to change due to large cabin space and simulation results. The fuel was chosen to 2'000 pounds estimated from the current VLJ D-Jet that had the

jet that was a good reference due to the similarities. The specifications gives us more information about the chosen size such as

jet on the amount of 1740 pounds of fuel. From the site FAA the student was able to find information regarding

e wings.”(FAA, 2008) this is referred to as A glass cockpit is an aircraft cockpit that features electronic instrument

Figure 6 Naval biodynamics

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displays. Where a traditional cockpit relies on numerous mechanical gauges to display information, a glass cockpit utilizes several computer displays that can be adjusted to display flight information as needed. This simplifies aircraft operation and navigation and allows pilots to focus only on the most pertinent information. They are also highly popular with airline companies as they usually eliminate the need to employ a flight engineer.

“In recent years the technology has become widely available in small personal aircraft.” (Wikipedia, 2008)

Comparing the different VLJ's gives some interesting information. Garmin 1000 is the only avionics in a VLJ that has been approved by European Aviation Safety Agency (EASA, 2008) Most VLJ that have done flight testing and have advanced to flight testing are using the Garmin 1000 (garmin, 2008). Those found having different avionics usually have installed a lighter version from the same producer such as G500 information found on various VLJ producers homepage.

The Body is often build up out of cylinders later in production mated together by bolts, there are some of the newer planes these days are built with a frame together with composite shell, however the commissioner expressed that he wanted the body to be made by aluminium. The difference changes in price / material, life and production time and methods. With the

conventional production, the student had too little time to go deeper than looking at current production ways and used materials. Information was found at different sites and books.

Aerodynamics

The optimal shape for least resistance of an object travelling through air is often referred to a drop of water, it automatically shapes itself to pass the air particles at the same time without losing it is homogenise body. This can also be observed from current natures own, the fastest bird Falco Peregrinus that has documented speeds up to 168 miles/hour. The body is elongated with two sleek wings and a tail for increased control. The head as the peak is progressively decreasing angle creasing as seen in mathematical curves such as Fibonacci spiral. The front should there for have a decreasing curve as seen on almost all current jet air craft’s. Obtaining “lift” with this shape is however not possible, Thus the obviously need of wings. There have been many other scientists who have tried to solve the calculation of flying one of the commonly used Bernoulli's principles that explains the movement of a particle is longer on the upper side of a wing thus creating the lift however this

theory has been proven not true. “Lift occurs when a moving flow of gas is turned by a solid object.” (NASA, 2008). This is calculated from Newton’s third law and seems to be the most accepted law from the different sites and books the student has studied. The student studied other aircrafts. After careful consideration the student choose the aerofoil most usable for this concept the sub-sonic aerofoil.(Federal aviation Administration Washington DC, 1980)

Figure 8 Aerofoils found in Pilots handbook of aeronautics knowledge

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Concept creation

For the project to be successful a fully 3D model was required from the commissioner he provided guidance and information regarding methods and aesthetic design where the student learned a lot. The first methods provided by the commissioner was the walk through (appendix 1.6) together with the mood board, used a lot among industrial designers these tools are for creating unified features, shapes and colours for a specific product. After creating the walk through the student created a function diagram (appendices 1.7) from the acquired information and from previous knowledge gathered. Sketching was chosen as the best method (p. 14), thinking up new ideas is easier and faster to note and illustrate with pen and paper than with 3D model program. It is a better solution then modelling the ideas that can sometimes be abstract and complex directly into modelling software. The

sketching started with creative sketching using tools such as tracing and mass amount sketching (p. 14)

”Standardization may not be as prevalent or profitable as perceived”Margaret Bruce, Lucy Daly, and Kenneth B. Kahn. The student have implicated this recommendation in the aesthetics of the project giving the concept the little extra edge and satisfying the commissioners request in areas such as window shape and tail wing. The sketches

were not dark enough to be portray well on computer and due to the weight and size the student decided to leave the hard copies in Canada, however a few sketches was recovered using Photoshop. See below for a few examples or (appendices 2.1)

Methods used here was initially to gain a creativity with creative sketching (p. 14) and then to mass produce ideas. (p. 14)

Figure 9 The used moodboard

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Figure 11 Detailed ideas and sketches

From the high number of ideas a number of seven concepts were chosen (p. 15) estimated to all meet the technical requirement from the project specification (appendix 2.2). The concepts were therefore evaluated on the Inspirational requirements using a modified list of design, Reference frames for design “Referensramar for Formgivning” (Rolf Lövgren, 2006). Key word evaluated on the concepts was as following:

■ Perception/Cognition ■ Anthropometry/Ergonomics ■ Marketing ■ Geometry ■ Shape design ■ Psychology

The concept that achieved the highest score was concept number six. (appendix 2.2.6) Figur 12:Choosen concept from Inspirational evaluation

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After the concepts had been evaluated the student continued to improve concept number six, a few of the recovered sketches can be seen below.

All the new sketches of concept 6 were presented where the commissioner pick the sketch he liked the most in order for the project to be inspirational for GadShaanan DESIGN, see below.

Figure 14 Sketch picked by the commissioner Figure 13 Several tracing scetches

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The picked sketch was chosen together with some mixed subtractions and additions found on other presented sketches. He wanted to add a split tail wing and the engine between, also found on a currently operational VLJ “The jet” (the-jet, 2008). He wished to make the main wings slimmer with longer reach and without the front stabilising wings and the air intake would be above instead of below.

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Development

This part of the thesis is where the student created the 3D model and evaluated the concept.

3D model creation

The student used the same model program as the company used which was Pro Engineer 2.0. After relearning the Pro Engineer (p. 16) the student continued to try and illustrate the concept. The student used the feature Assembly with a skeleton model. The function of the skeleton model is to:

• contain key assembly constraints

• act as a conduit for “sketching” a design by adding geometry to complement a layout • serve as the hub of data sharing

• allow assembled components to interact with the parent assembly, insulating it from

failure of component placement. (PTC, 2008)

These functions made it easier to model and have a reference to work from. The 3D modelling was harder than the student initially had anticipated; more over the software had problems implementing changes later in the process thus leaving the student no choice but to restart from scratch a certain number of times. Reference measurements calculated from earlier were added such as length, width and circular diameter. After several rebuilding the student was finally able to get the required shapes, using methods such as skeleton sketching, surfacing, polishing curves and more. (p. 16)

The commissioner helped to sketch over printed views of the 3D model to improve curves and focus the student on the chosen concept. When everything had been done with the exterior it was time to start the rendering according to the Gantt, time had flown away on small problems and the student rushed trying to build the interior along with seats etc. together with preparing the exterior for renderings.

While designing the seats the commissioner pointed out that the seats were floating inside the VLJ. Even though using references the sizes had become abnormal. The extra large cabin space was not calculated, leaving the student with an almost too large VLJ. Unable to resize the plane due the fact that the software could not resize such a complex 3D model, the student had to make a choice how to handle the problem. A to large plane could compromise the performance in an unanticipated way and having “a too large cabin” would even if correct in size not look real, thus making the final inspirational images not convincing. The student thought that a size change could be a good solution and it would mean less required thrust while performance would go up, according to Mr Kingham (certified pilot and computer specialist). The change

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from 40x40 ft to 30x30 ft would mean a thrust of 2013 lb instead of the calculated 2559 lb calculated with the least point method. To verify the new estimation the student resized the seats larger instead of sizing the air plane smaller. Next page shows two figures of before and after the size change.

The results were better than expected. Some adjustments would have to be done; the walls at the moment of the testing were somewhat too big for arm support and the future features such as work table and cup holder.

Simulation and adjustments

Simulations was done in an software called X-plane that can handle personal made 3D objects and enter estimated specifications it can then calculate and simulate flight using bladed element theory.

Blade element theory (BET) is a mathematical process originally designed by William Froude (1878), David W. Taylor (1893) and Stefan Drzewiecki to determine the behaviour of propellers. It involves breaking an airfoil down into several small parts then determining the forces on them. These forces are then converted into accelerations, which can be integrated into velocities and positions.

(wikipedia, 2008)

The blade element theory is based on the same principals as NASA calculates with as presented in creation activity (p. 21) of the project; however the software simulates forces on divided surfaces instead of the stated gas particles moved by a solid objects surface.

During simulations Mr Kingham made some improvements to the performance testing different specifications while the student was able to find a new engine that could match the new thrust. From the simulations a thrust of 1800 would be appropriate, The student used the old

calculations and found that the answer was good with the least point calculation, outcome was a speed of 340 KTS. The student found the Williams FJ33-4A-19 a perfect match for the concept VLJ. The dimensions have been taken from the (williams,2008). However the exhaust pipe was a little short to direct the thrust stream 100% in the right direction at this stage the student could not implement any new changes.

Figure 18 3D model large version

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Mr Kingham then used the specific

X-plane due to the fact that the model was not compatible for the not exactly same windows. He then t

thumbs up in aviation attributes

from the flight can be acquired from the student and this film will be available in t will be sent to the commissioner.

There were some changes such as a was calculated to 1'500 pounds.

miles, using a percentage calculation with the same engine and roughly the same weight. 1350 nm / 1740 lb = 0.78 nm/lb

This gave the concept longer flight than three current VLJ's and around the same as two others. The concept VLJ have been added to the weight of current VLJ's from earlier together with the new specifications and can be vie

Figure 21 A few screen shots from the first simulated flight

used the specific dimensions from the concept and recreated the model for plane due to the fact that the model was not compatible for the simulations program

not exactly same windows. He then test flew the concept in X-plane (x-plane

thumbs up in aviation attributes, nice handling and an overall nice flight. A recorded video from the flight can be acquired from the student and this film will be available in t

ll be sent to the commissioner.

There were some changes such as a new fuel size to lower the MTOW, after the simulation it was calculated to 1'500 pounds. This would lower the estimated range to around 1163 nautical

ge calculation with the same engine and roughly the same weight. 740 lb = 0.78 nm/lb →1500 lb * 0.78 nm/lb ≈ 1164 nm

This gave the concept longer flight than three current VLJ's and around the same as two others. The concept VLJ have been added to the weight of current VLJ's from earlier together with the new specifications and can be viewed on appendices 3.

A few screen shots from the first simulated flight

dimensions from the concept and recreated the model for simulations program thus the

plane, 2008) giving it an overall nice flight. A recorded video from the flight can be acquired from the student and this film will be available in the disc that

fter the simulation it the estimated range to around 1163 nautical ge calculation with the same engine and roughly the same weight. This gave the concept longer flight than three current VLJ's and around the same as two others. The concept VLJ have been added to the weight of current VLJ's from earlier together with the

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Visualising the concept in realistic way

”some degree of localization or rationalization is necessary to make the product acceptable to the market” (Margaret Bruce, Lucy Daly, and Kenneth B. Kahn, (citing Kotler , 2000))

In order to give the commissioner the most realistic concept the student took a photo in a local environment, mounted a rendering of the 3D model and edited them the rendering to fit with each other. This was done to make the most realistic image where the user, commissioner and employees of GadShaanan DESIGN, can

identify themselves with. The settings in Pro Engineer are limited and were trials for the student get some good renderings during the short period of time remaining. The student printed two images to show the commissioner before returning home to Sweden. The student

have created a couple more printable images on arriving in Sweden that will be additional inspiration this will be burned to a disk and sent to the commissioner together with this report and the Pro Engineer 3D model.

QFD Evaluation of concept versus competitors

The requirements of this subjective statement the concept had to be evaluated from the final customer which in fact is the commissioner. His response to the final print outs was that there were some things that had some interest to them. However a QFD was made to evaluate and verifying the results between the most interesting VLJ's. To QFD used partially collected and estimated data. (appendices 5)

The concept VLJ meets the requirements from the market best of the four. However it was Figure 23 Photo taken in Montréal by the student

Figure 22 Rendering of concept VLJ

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8. Results

The documentation below is the results of this project. The results below can be followed up with the project specification and use as a reference to compare if the problems have been solved.

Choosing the appropriate methods for designing a Very Light Jet

The list of methods used in this thesis has

are from the read literature and some of them have explicitly been made to suite this project.

Using the chosen methods in a controlled and traceable way

All the methods used can be checked on the Gantt

the student have been able to control and document the progress of the project. The documentation can now be used to trace back steps and actions in a time line.

Designing a Very Light Jet

Documented files for further development has not been required to present to the

commissioner, however a disc will be sent to the commissioner. The disc containing the inspirational illustrations, 3D model, produced results from each method together with gathered information such as links, contacts and research documentation including this thesis.

Meeting the technical requirements

Below are the final specifications of the Concept check it against the stated project specification Weighing less than 10000 pounds The estimated maximum takeoff

below the required VLJ mark 10'000 pounds.

structured with partial cylinders mated together to create the body, as done in conventional air plane.

Transporting passengers

The transportation specifications have been chosen optimal at 6 pax. Where 1 seats in the front and the rest 4

VLJ such as on a sports car, one o

thus removing the conventional aisle giving more space on each sides for larger arm rests and more robust work tables, meeting the requirements of relaxation and work space. The interior diameter has been set to 6.1 ft, which is still a large cabin size compared with others.

the results of this project. The results below can be followed up and use as a reference to compare if the problems have been

Choosing the appropriate methods for designing a Very Light Jet

list of methods used in this thesis has all been explained in chapter 6 and 7. Most of them

e read literature and some of them have explicitly been made to suite this project.

Using the chosen methods in a controlled and traceable way

All the methods used can be checked on the Gantt schedule (appendix 1.2), with n able to control and document the progress of the project. The documentation can now be used to trace back steps and actions in a time line.

Designing a Very Light Jet

Documented files for further development has not been required to present to the

ssioner, however a disc will be sent to the commissioner. The disc containing the inspirational illustrations, 3D model, produced results from each method together with gathered information such as links, contacts and research

thesis.

requirements

final specifications of the Concept VLJ, here we can see the final results and project specification (appendix 1.1).

10000 pounds

takeoff weight of the air plane will be 5'500 pounds. There for far mark 10'000 pounds. The material used is mainly aluminium that is structured with partial cylinders mated together to create the body, as done in conventional air

The transportation specifications have been chosen optimal at 6 pax. Where 1

seats in the front and the rest 4-5 are passenger seats. There are two entrances to the concept VLJ such as on a sports car, one on each side, giving a smooth and easy exit for the customer, thus removing the conventional aisle giving more space on each sides for larger arm rests and more robust work tables, meeting the requirements of relaxation and work space. The interior

r has been set to 6.1 ft, which is still a large cabin size compared with others. Figur 25 Overview of the concept VLJ the results of this project. The results below can be followed up

and use as a reference to compare if the problems have been

Choosing the appropriate methods for designing a Very Light Jet

all been explained in chapter 6 and 7. Most of them e read literature and some of them have explicitly been made to suite this project.

Using the chosen methods in a controlled and traceable way

1.2), with this schedule n able to control and document the progress of the project. The

documentation can now be used to trace back steps and actions in a time line.

, here we can see the final results and

weight of the air plane will be 5'500 pounds. There for far material used is mainly aluminium that is structured with partial cylinders mated together to create the body, as done in conventional air

The transportation specifications have been chosen optimal at 6 pax. Where 1-2 seats are pilot 5 are passenger seats. There are two entrances to the concept

n each side, giving a smooth and easy exit for the customer, thus removing the conventional aisle giving more space on each sides for larger arm rests and more robust work tables, meeting the requirements of relaxation and work space. The interior

r has been set to 6.1 ft, which is still a large cabin size compared with others. Overview of the concept VLJ

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Flying with jet engine

The engine chosen for the concept VLJ is one Williams FJ33-4A-19, which has a thrust of almost 1900 pounds. 1500 pounds fuel will be stored in the wings.

Advance avionics

Due to the efficiency and proven usefulness Garmin G1000 was chosen as the best avionics instrument panel for the concept VLJ.

Meeting the inspirational requirements

Below are the inspirational requirements compared with the results.

A concept to give inspiration for other projects

Printable inspirational illustrations of the concept will be sent to the commissioner for easy use in other projects.

Figur 27 Concept VLJ engine placing

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Evaluation of attractiveness

The requirements of this subjective perception was evaluated from the final customer which in project is the commissioner. The response was that there were some interesting ideas and shapes that could be of use for them.

Visualising the concept in realistic way

The image below is one of the two printed images shown to the commissioner. These images along with some more like the one above will be sent to the commissioner as printable material for inspiration usage.

Simulation results from X-plane

The simulation results such as take off speeds lengths, in flight data and weights can be found in appendices 4, a simulated flight video can be acquired from the student on disc. Something to note is that maximum cruise speed is as high as 340 kts; minimum runway is 1200 ft and almost half the weight requirements 5'500 lb.

Figur 30 One of the inspirational renderings of the concept VLJ Figur 29 Rendering of concept VLJ

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9. Analysis

The student have here analysed his work and the achieved results.

Resources Analysis

Below is an analysis of the different activities and the produced result.

The problem statement and the achieved result

Looking at the project specification and the results at the same time, it shows that the proposed concept is a functional concept that weighs less than 10000 pounds, uses advanced avionics, can transport passengers and operates with a jet engine not only with the specifications but also with the verification of the simulation flight. The concept is of course in theory and this should be taken in consideration, the specifications from the project are only defining the shell of the concept jet. The demand to make the concept attractive has been proven by basing its

conclusions on the target consumer, there taste and opinion has been emulate onto the concept jet. The commissioner has expressed his thoughts on the project where as some parts were interesting for them in the future, thus making the project useful as a inspiration and fulfilling the last demand the specified problem statement.

Analysis of the chosen methods

Analysis

The information gathering and overall structure of the analysis part was well defined by

literature (Ullman, 2003, p. 10) and is a core for producing a good result. There were some lack of restrictions in depth of the project and a method or process for defining this would have been useful.

Creation

The proposed methods have been taken from literature and a few provided to the student by the commissioner. Most of the methods from the commissioner were used to improve the overall design and aesthetics of the concept, methods from the student was used to specify key parts of the concept. The use of the methods from two different sources that was not included to each other made it hard to merge the methods together creating the concept more divided then homogeneous. The QFD should have been used during the creation phase for a more well defined evaluation method, however the results are likely to have been similar.

Development

The first part of this phase methods were intended to specify at the same time create 3 dimensional visual parts, improving productivity and utilized maximum time. The methods enhance the reality of the concept thus improving the inspirational concept. The simulation and

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Summery and documentation

Gantt was chosen as method to document and follow the project progress. Additional

documentation methods such as intelligence from analysis phase were also used to keep track and create useful information.

Designing a very light jet

Designing a Very Light Jet

Master thesis work

30 credits, D-level

Per Nyblom

Abstract

Introduction

Problem

Method

Result

Acknowledgements

Contents

1. Introduction

About VLJ’s

About GadShaanan DESIGN

Purpose of this thesis

2. Aim of project

3. Project directives

Commissioners directives

Students directives

4. Problem statement

Project Specification

Technical requirements

Inspirational requirements

5. Project limitations

Time and money

Analysis, creation and development

6. Theoretical background, solutions &

methods

Analysis

Creation

Sketching

Development

3D modelling

Model Rendering

Testing and flight simulation

QFD

7. Applied solution procedures

Analysis

Creation

Aerodynamics

Concept creation

Development

3D model creation

Simulation and adjustments

Visualising the concept in realistic way

8. Results

Choosing the appropriate methods for designing a Very Light Jet

Using the chosen methods in a controlled and traceable way

Designing a Very Light Jet

Meeting the technical requirements

Choosing the appropriate methods for designing a Very Light Jet

Using the chosen methods in a controlled and traceable way

Designing a Very Light Jet

requirements

Choosing the appropriate methods for designing a Very Light Jet

Using the chosen methods in a controlled and traceable way

Meeting the inspirational requirements

Simulation results from X-plane

9. Analysis

Resources Analysis

The problem statement and the achieved result

Analysis of the chosen methods

Analysis

Creation

Development

Summery and documentation