AIRCRAFT UNDERCARRIAGE DESIGN CHALLENGE

Introduction

In order to reduce aircraft noise, engineers are looking at ways to make a quieter undercarriage, which is one of the major noise sources on a landing aircraft.

Your task, working via the internet in a virtual learning environment (VLE) with all the other members of your team with an assigned member of the Cambridge University Engineering Department (CUED) acting as an adviser, is to design/draw a model of a quiet undercarriage, using the computer-aided design (CAD) package specified. You and your team will then come to Cambridge for a day to build and test a working model of the design with the components/materials supplied/made by the CUED workshops.

Task Description

NAGTY PROJECT GUIDELINES FOR PARTICIPANTS

The requirements for the undercarriage design are as follows:

1. The undercarriage must be capable of supporting a load of 3 kg.
2. Maximum height of the undercarriage without load must be less than 300 mm and more than 290 mm.
3. Minimum height of the undercarriage under a load of 3 kg must be more than 200 mm and less than 210 mm.
4. The undercarriage must be capable of rolling forwards 2 m while carrying a load of 3 kg.
5. The interface at the top of the undercarriage must be an M16 thread between 40 and 45 mm long.
6. The undercarriage must be capable of withstanding a wind speed in the wind tunnel of 20 m/s.
7. The undercarriage should be as light as possible.
8. The undercarriage can be built using only the parts provided
9. The fairing must be detachable from the undercarriage
10. The undercarriage must meet all the above requirements both with and without the fairing fitted.

If your undercarriage passes these tests, it will be passed for wind tunnel testing over the acoustic array, where its noise output will be measured. The first test will be with the bare undercarriage to assess the worst-case noise level. A second test will then be run with the fairing in place, allowing the noise reduction to be quantified.

The team that produces the quietest undercarriage will be deemed the winner.

The document "Practical Guidelines for Mechanical Design and Manufacture", which can be found here http://www-mdp.eng.cam.ac.uk/resources/enginfo/mechanical/practical_guidelines.pdf provides some useful general information.

GETTING STARTED

We have assembled a range of support materials in the VLE to help your team undertake this challenge. The amount of information may seem overwhelming at first. Therefore we would suggest that you focus initially on learning about Project Management and the Engineering Design Process.

To help you generate your own ideas for possible solutions to this problem we have provided some general information about undercarriage design, some information about existing undercarriages and some advice about how to approach the design of a quiet undercarriage.

We have also provided a range of information to support the detailed design of your model undercarriage. Real-world engineering project teams are usually multidisciplinary with engineers with different areas of expertise (Mechanical Engineers, Structural Engineers etc.) contributing to the design process. Rather than expecting every member of your team to take in all the information provided, you may find it more effective to allocate responsibility for different aspects of your design to individual team members.

The materials and standard components you have to work with are detailed in the Kit List. A decision your team will have to make quite early on is how your undercarriage will support the load and deflect within the required limits: will it be a telescopic design or a jointed design? What are the advantages and disadvantages of each approach? What adjustments might be necessary to fine tune your model to pass the requirements and how will you build these into your design? Can you then build your design from the components available in the kit?

SUBMISSION OF DRAWINGS

As part of this challenge your team has to produce manufacturing drawings for your design using the CAD package provided. These drawings have to be submitted to us by 10 March 2006 accompanied by a short document explaining how your design is intended to work to help us interpret the drawings.

We will provide feedback on your design by 20 March 2006. You will then have the opportunity to modify your design in the light of this feedback. Final CAD drawings for your design have to be submitted by 31 March 2006.

MANUFACTURE OF COMPONENTS

Using the drawings you have submitted our technicians will manufacture the metal components in your design in our workshops. Alternatively, if you have access to suitable workshop facilities at school/college or at home, you can opt to manufacture some or all of these components yourself. If you do opt to make components yourself, please remember to bring them with you when you come to Cambridge for the finale.

FINALE

In the finale of this challenge you will come to CUED on either 22 April 2006 or 29 April 2006 to meet the rest of your team and your adviser face-to-face, to assemble and fine-tune your design, and then formally test it. The timetable for the day is:

10.00 - Arrival and registration

10.15 - Teams assemble, test and fine-tune designs

13.15 - Lunch break

14.00 - Tinkering time

15.00 - Formal test of each design

15.30 - Tour of the Department

16.15 - Presentation about the Silent Aircraft Initiative

17.00 - Participants depart

POST-MORTEM

After the finales we will assess your designs through discussion (to which all can contribute) in the VLE. The aspects of the designs to be considered will include aesthetics, ingenuity, the ability of the undercarriage to meet the design requirements, structural integrity, the effort put into reducing weight and the overall noise reduction provided by the fairing. Discussion will also cover issues related to scaling the models up to full-size.

SUMMARY OF CHALLENGE CALENDAR

23 Jan 2006 - Challenge starts

10 Mar 2006 - Deadline for initial design drawings

20 Mar 2006 - Feedback on designs from Cambridge

31 Mar 2006 - Submission of final design drawings

3-21 April 2006 - Manufacture of components

22 April 2006 - First Challenge Finale in Cambridge

29 April 2006- Second Challenge Finale in Cambridge