SELECTED ASPECTS OF THE 2010 POLISH AIR FORCE ONE CRASH MSME, GLENN ARTHUR JØRGENSEN. DENMARK 24 JULY 2013 Background of the Author Engineer with a master degree in fluid dynamics and structural analysis in 1988. Worked as a co-teacher within fluid dynamics at the Danish Technical University (DTU). Has completed the courses held by the institute of Fluid Dynamics at DTU related to aviation and building of aircrafts. Working past 15 years as consultant performing various simulations and analysis, including structural FEM analysis. In free time a privat pilot since 1982 flying single engine aircrafts (C172, PA28) for pleasure purpose only. (No military aviation experience. No Jet plane experience.) Aim of this work Estimate trajectories and roll angle related to the two cases: Case I : Loss of wing tip as stated in MAK report. Case II : As Case I + additional wing loss at second large dip in the measured vertical acceleration. Estimate the height of the airplane at the point of the birch tree by reverse engineering. Discussion of selected items. Remaining of P101. Vertical acceleration data from the Russian MAK Report. Boundary Conditions and Assumptions Vz at the point of the birch tree is processed through a time wise double integration of the measured vertical acceleration data from an arbitrary starting point prior to the birch tree of interest and at a point with relatively well defined initial boundary conditions (here at a radio height of about 49m). X,Y,Z at site of crash Weight in landing mode as estimated in MAK. (78.6 ton) Estimated Moment of Inertia about the length axis, Ixx, scaled from similar airplane (727-200) Wing Lift Data : CL(flaps down)/CL(flaps up) = 2.20 Change in lift coefficient KL=0.075deg-1 Vplane = 265km/hr Linear relationship between angle of attack and force of lift. Newton’s II law of motion. Mathematical Relationships Results – Case I, Loss of Wing Tip Only Results – Case I, Continued Less than 5% loss of lift Plane would not crash. Position would be 30m north and 40m above the site of crash. Reported roll angle and roll angle velocity do not correlate with calculated values. Ground traces do not correlate with reported position and wing length (se following slides). Results – Case II, Additional wing loss Results – Case II, Continued Final Vz ≈ -18m/s Final Vx ≈ 70m/s Angle of trajectory towards the ground ε ≈ -15deg ERRATIC RUDDER BEHAVIOUR Reported Wing Fragment Locations ORIENTATION OF PLANE AT CRASH (CASE I) 150° ROLL, -6 ° INCLINATION, ONLY LOSS OF WING TIP ORIENTATION OF PLANE AT CRASH (CASE II) 130° ROLL, -6 ° INCLINATION, ε ≈ -15deg ,EXTRA WING LOSS (SHORT WING) GROUND TRACES Results – Case II, Additional wing loss Vertical and horizontal trajectories correlate with FMS data point, position of birch tree and final site of crash. Reported roll angle and roll angle velocity correlate with calculated values. Ground traces confirm Case II and disagree with Case I Height above terrain at site of birch tree is found to be more than 11m. Theory of additional wing loss can explain erratic behavior of the left rudder actuator and findings of the left wing close to the highway. SUMMARY Results - Summary According to the presented calculations the loss of wing tip only (Case I) cannot explain: The theory of additional wing loss (Case II) result in good correlation between: the site of crash of the plane (It should continue to climb to a height of about 40m at a position 30m north of the crash site, the final roll angle as reported The recorded roll angle velocity the ground traces of left wing and tail the erratic behavior of the left rudder actuator during its final seconds of flight. Vertical and horizontal trajectories and FMS data point, position of birch tree and final site of crash. Calculated and reported roll angle and roll angle velocities. Ground traces as seen on satellite photos and calculated values Location of left wing fragments Height above terrain at site of birch tree is found to be more than 11m. Theory of additional wing loss (Case II) can give some explanation to the erratic behavior of the left rudder actuator. CONCLUSION 1. 2. 3. 4. The loss of lift related to the loss of the wing tip only would not bring the plane to crash. A likely scenario of the events would be consistent with this study's Case II (additional loss of left wing area), this would also explain other additional problems. The results refute the possibility of the birch breaking the wing. This is consistent with the results of other studies. (W. Binienda, C. Cieszewski, K. Nowaczyk) In the light of the results presented in this study the MAK report accounts of the event are likely inaccurate, and leave many questions unanswered. Some questions unanswered by the MAK report Why did the two FMS computers loose power 70m before the crash? What caused the second dip in vertical acceleration 50m after the position of the Birch tree? What caused the left rudder actuator to behave erratic at the time of the second dip in vertical acceleration? What caused the left rudder actuator to behave erratic at the time when the tail was lost about 70m before the crash? Why do the tail and wing traces not correlate with the stated position of the plane at the time of crash? Why was the left tail part moved to and reported at a position 35m closer to the site of crash? What other warnings and errors did the FMS report prior to the crash? Which calculations can confirm that the loss of tip could cause the plane to roll 150deg and crash as reported? References Final Report Tu-154M tail number 101, Republic of Poland, by the "Interstate Aviation Committee", English translation. LsDyna3D Simulations and Analysis of Polish Govermental Airplane TU154M Crash in Smolensk, Russia, April 10, 2010. University of Akron, Professor W. Binienda. Nov 25, 2012. Report No. 456 "SOME MECHANICAL AND STRUCTURAL ASPECTS OF THE SMOLENSK AIR CRASH“ by Dr. Gregory Szuladzinski, MSME , version 6, May 2012. MAK and KBWLLP reports data analysis. PH.D. Kazimierz Nowaczyk, Ph.D. Assistant Professor at the University of Maryland . TAWS DATA EXTRACTION FOR NTBS IDENTIFICATION : ENG10SA025, ORIGINAL 28.06.2010 Additional aspects of the Smolensk Air Crash, G.A. Jørgensen 0604-2013. Special thanks to Mr. Marek Dabrowski and Jan Andrzejewski for relevant feedback, questions, support and additional information.