| Date | November 2018 | Marks available | 3 | Reference code | 18N.2.SL.TZ0.1 |
| Level | SL | Paper | 2 | Time zone | no time zone |
| Command term | Explain | Question number | 1 | Adapted from | N/A |
Question
The Boeing 787 aircraft was designed to be 20% more fuel efficient than its predecessors and is based on light-weight construction. The Boeing 787 is the first major commercial aircraft to have a composite fuselage, composite wings, and to use composites in most other components, see Figure 1.
The Boeing 787’s cabin windows are larger than any other civil aircraft and are composed of photochromatic smart glass.
[Source: © International Baccalaureate Organization 2018]
Figure 2 shows the use of an instrumented model during the development of the aircraft’s wings.
[Source: © International Baccalaureate Organization 2018]
State the percentage of composite used in the production of a Boeing 787.
Outline which physical property would have the greatest impact on the fuel consumption of a plane.
Outline why photochromatic glass is an appropriate material for the windows of the Boeing 787.
Outline why magneto-rheostatic smart materials would be used in the landing gear of the Boeing 787.
List two advantages of using finite element analysis (FEA) for the design of the Boeing 787 wings.
Explain how instrumented models have been used in the development of Boeing 787 wings.
Markscheme
50% ✓
Award [1] for stating the percentage of composite used in the production of a Boeing 787.
low mass/weight ✓
requires less energy/fuel (to fly) ✓
high mass/weight ✓
requires more energy/fuel (to fly) ✓
Award [1] for identifying a physical property that would have the greatest impact on the fuel consumption of a plane and [1] for a brief explanation.
(answer in brackets not required to award mark)
the properties of photochromatic glass allow it to tint/change opacity when exposed to (UV) light/the voltage is controlled ✓
which blocks the sunlight so that passengers are more comfortable/protected from sun glare/eliminating the need for physical shade/blind ✓
Award [1] for identifying why photochromatic glass is an appropriate material for the windows of a Boeing 787 and [1] for a brief explanation.
Do not accept ‘change colour’.
magneto-rheostatic fluids change their viscosity when exposed to a magnetic field ✓
which means that the impact of landing can be reduced/made safer ✓
Award [1] for identifying why magneto-rheostatic smart materials would be used in the landing gear of the Boeing 787 and [1] for a brief explanation.
test the structural integrity/stresses of the wing ✓
overcomes expensive performance testing/is more cost effective ✓
test the aerodynamics under various conditions ✓
test thermal exchange of interior/exterior under various conditions ✓
the designer can quickly make changes to the CAD drawing to improve the design of the wing ✓
Award [1] for each advantage of using FEA analysis for the design of the Boeing 787 wings.
instrumented models allow measurements to be taken that provide accurate/quantitative feedback for analysis ✓
the wings on the 787 have been tested under various simulated conditions ✓
this ensures that the wing can safely operate/resist stress during operation/improve the design ✓
Award [1] for each of three distinct points in an explanation of how instrumented models have been used in the development of Boeing 787 wings.
Examiners report
Syllabus sections
- 18N.1.SL.TZ0.12: What type of prototype is designed to collect quantitative data to help inform...
- 19N.1.SL.TZ0.12: Which of the following modelling techniques would most likely be used to understand how well...
- 17N.1.SL.TZ0.12: Clay models, scale models and prototypes are all examples of which type of modelling? A....
-
17N.1.SL.TZ0.11:
Figure 3 shows a car design modelled from clay.
Figure 3: A clay model of a car
[Source: https://commons.wikimedia.org/wiki/File:Opel_50_Jahre_Design_(14541643013).jpg, by Robert Basic]
Which of the following best describes a model that shows exactly how a product could look but not function?
A. Mock-up model
B. Prototype model
C. Realistic model
D. Aesthetic model
- 20N.1.SL.TZ0.13: What best describes a physical model that can be used to test ergonomic features but does not...
-
20N.2.SL.TZ0.6d:
Explain the role of rapid prototyping, instrumented physical models and computer aided design (CAD) in the design of the modern rotor sail.
-
21N.2.SL.TZ0.6a:
List two forms of graphical modelling used by car designers.
-
19M.2.SL.TZ0.1d.i:
List one reason why clay modelling is still used to prototype models in processes such as car design.
-
21N.2.SL.TZ0.7d:
Explain the benefit of using freehand sketches, physical models and CAD solid models in the development of the horn of the Gramovox® bluetooth speaker.
-
19N.2.SL.TZ0.6b:
Explain why prototypes would be used in the testing and evaluation of the brick made by the Treak community.
