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Transcript Dias nummer 1

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
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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
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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)
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150° ROLL, -6 ° INCLINATION, ONLY LOSS OF WING TIP
ORIENTATION OF PLANE AT CRASH (CASE II)
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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
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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
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According to the presented calculations the loss of wing tip only (Case I) cannot explain:
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The theory of additional wing loss (Case II) result in good correlation between:
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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
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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
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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.