Hall Ticket No Course Code AAE006
INSTITUTE OF AERONAUTICAL ENGINEERING
(Autonomous)
Four Year B.Tech IV Semester CIE II, May 2018
Regulations: IARE-R16
ANALYSIS OF AIRCRAFT STRUCTURES
Time: 2 Hours Max Marks: 25
Answer all question from Part A
Answer any four questions from Part B
All parts of the question must be answered in one place only
PART A
1. Write the value of IXY for unsymmetrical section. Remember CO: 2 Marks:
Write about air loads. Understand CO: 2 Marks:
Write the equation to find out the bending stress of idealized panel.
Remember CO: 7 Marks:
If the shear force is 400 N over the length of the 200 mm stiffener, what is the shear flow.
Remember CO: 9 Marks:
Explain the functions of fuselage frames. Understand CO: 11 Marks:
PART B
2. In order to understand open sections, one has to be clear about centroid, neutral point and shear
centre. Explain them with mathematical expression. Understand CO: 4 Marks:
A beam having the cross section shown in Figure 1 is subjected to a bending moment of 1500
Nm in a vertical plane. Calculate the maximum direct stress due to bending stating the point at
which it acts. Understand CO: 4 Marks:
Figure 1
Page 1 of 3
3. Derive the equation to find out the bending stress of idealized panel, if My equal to zero with
neat sketch. Understand CO: 1 Marks:
Part of a wing section is in the form of the two-cell box shown in Figure 2 in which the vertical
spars are connected to the wing skin through angle sections, all having a cross-sectional area of
300 mm2. Idealize the section into an arrangement of direct stress-carrying booms and shearstress-
only-carrying panels suitable for resisting bending moments in a vertical plane. Position
the booms at the spar/skin junctions. Remember CO: 1 Marks:
Figure 2
4. Draw the neat sketches of idealized simple wing section. Derive bending stress and shear flow
distribution. Understand CO: 8 Marks:
The fuselage section shown in Figure 3 is subjected to a bending moment of 100 kNm applied in
the vertical plane of symmetry. If the section has been completely idealized into a combination
of direct stress carrying booms and shear stress only carrying panels, determine the direct stress
in each boom. Understand CO: 8 |Marks:
Figure 3
5. Explain torsion on three boom shell with neat sketch. Understand CO: 8 Marks:
The beam shown in Figure 4 is simply supported at each end and carries a load of 6000 N. If
all direct stresses are resisted by the flanges and stiffeners and the web panels are effective only
in shear, calculate the distribution of axial load in the flange ABC and the stiffener BE and the
shear flows in the panels. Understand CO: 8 |Marks:
Page 2 of 3
Figure 4
6. Derive the equation to find out shear flow in a tapered wing.
Understand CO: 11 Marks:
If the web in the wing spar of Figure 5 has a thickness of 2mm and is fully effective in resisting
direct stresses, calculate the maximum value of shear flow in the web at a section 1m from the
free end of the beam. Understand CO: 8 |Marks: