Crash of the Polish Governmental Plane Tu-154M Smolensk, Russia, on April 10, Numerical verifications of the official conclusions

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1 Crash of the Polish Governmental Plane Tu-154M Smolensk, Russia, on April 10, 2010 Numerical verifications of the official conclusions

2 Airplane Tu-154M Crash - Verifications 2

3 Kyrgyzstan Jet Crash-Landing Injures 31 3

4 Moscow TU-154 plane crash injuries reached to 83 on Dec 5,

5 Crash Tu154 into a Steel Structure 5

6 Russian Final Report Section The aircraft collided with the birch with a trunk diameter cm, which led to the left outer wing portion of about m long ripped off and intensive left bank. Section In 5-6 more seconds, inverted the aircraft collided with the ground and was destroyed. 6

7 Last seconds before the crash 7

8 Question # 1 Is it possible that the Tu-154M airplane lost a major part of the wing as a result of hitting the Birch? 8

9 Internal structure of the wing Tu-154M 9

10 Spar Cross-sections 230mm 10

11 Inner wing structure Boeing

12 Material parameters of the birch tree Young s Modulus (MPa) Poisson Ratio Shear Modulus (MPa) Density (Kg/m 3 ) E L E R E T ν LT ν RL ν RT G TL G LR G RT Birch1 Birch Birch- elastic, cylindrically orthotropic; 12

13 Parameters of the Aluminum Tu-154 Parameters of Aluminum D16, V95, AK6, etc. Density(Kg/m 3 ) Young s modulus, E(Pa) Yield Stress(Pa) Tangent Modulus, Ec (Pa) Poisson Ratio, ν Failure Strain E E E Aluminum: isotropic, elasto-plastic hardened, 13

14 Strain Rate Dependence of Aluminum 900 stress vs plastic strain stress (MPa) /s /s /s /s /s Plastic strain 14

15 Internal Structure of the Wing 15

16 Validation of leading edge 16

17 Leading edge Validation Wen Zhi Wang, Northwestern Polytech U. 17

18 Fuselage Validation 18

19 Birch Three Point Bending Tests Density of the birch sample = 700 kg/m3 19

20 Methodology of Analysis LsDyna3D Simulation Parameters Velocity: m/s horizontal, m/s vertical up Plane mass: kg Distance from the base to the tree cut : 6m - 6.5m Birch diameter at the cut section: 40cm - 44 cm Birch density: kg/m 3 Location of the impact on the wing from its tip: 3m - 7m Several plane orientations: Horizontal, Nose up: 5 20 Roll -5 horizontal Roll -5 and pitch

21 Math and Physics Background in CFX Ansys- CFX analysis conducted by UA Research Fluid Mechanics Laboratory. Full form of Navier-Stokes equations with continuity of the flow. 21

22 Overall Pressure Contour

23 Wing Pressure Contours Bottom Top 23

24 Widok z lewej strony samoloty 24

25 Widok od Strony Samolotu 25

26 Zblizenie 1 26

27 Zbliżenie 2 27

28 Naprężenia w brzozie i skrzydle 28

29 Naprzenia w brzozie i skrzydle 29

30 Conclusions # 1 Based on the parameters provided in the official reports, the model shows that the wing of the Tu-154M plane cuts through the birch for every analyzed scenario. The damage to the wing is localized on the edge, does not deteriorate the lift surface of the wing, thus should not significantly reduce the ability of the plane to fly. Above simulations have been consulted with and positively evaluated by BOEING Principal Structural Engineer Dr. Waclaw Berczynski. 30

31 Left Wing Reconstruction View From the Bottom Up Front Edge(Part 9) not Damaged 1 CENTROPŁAT LEWY 2 ODEJMOWANA CZĘŚĆ SKRZYDŁA LEWEGO (FRAGMENT POCZĄTKOWY POSZYCIA SPODNIEGO Z SZACHOWNICĄ) 3 ODEJMOWANA CZĘŚĆ SKRZYDŁA (KOMPLETNA CZĘŚĆ KOŃCOWA) 4 DEFLEKTOR (FRAGMENT KOŃCOWY) 5 FRAGMENT KOŃCOWEJ CZĘŚCI KLAPY OCZS. 6 FRAGMENT ŚRODKOWEJ CZĘŚCI KLAPY OCZS. 7 REDUKTOR MECHANIZMU WYSUWANIA LOTKI-INTERCEPTORA 8 FRAGMENTY POSZYCIA ODEJMOWANEJ CZĘŚCI SKRZYDŁA 9 SLOT ŚRODKOWY, SEKCJA 2 (FRAGMENT KOŃCOWY) 10 SLOT ŚRODKOWY, SEKCJA 2 (FRAGMENT ŚRODKOWY) 11 SLOT ŚRODKOWY, SEKCJA 2 (FRAGMENT POCZĄTKOWY) 12 SLOT ŚRODKOWY, SEKCJA 1 (FRAGMENT KOŃCOWY) 13 SLOT WEWNĘTRZNY 14 WYRWANY DŹWIGAR NR 1 CENTROPŁATA Z FRAGMENTEM POSZYCIA 15 WYRWANY BLOK KLIMATYZACYJNY Z POSZYCIEM 31

32 Simulation of Fuselage with Explosion Sandia National Lab CNN

33 Fuselage Walls Open Outside 33

34 How to make a progress? 1. Get several samples of a Birch Tree, measure density, stress-strain in axial and transverse directions. Generate acceptable to all material properties and publish them. 2. Publish blue prints of the wing. Include thicknesses and other dimensions of the internal structure and outside components of the wing (slats, flaps, etc). 3. Encourage to conduct research based on the above data so researchers may be able to further develop simulation techniques and methodologies, help to establish realistic scenarios of the crash, while avoiding any political ramification. 4. Be friendly to your colleagues. 34