ESA PADRE Analysis Results

Overview | Fragment Composition

Test case: PADRE Steel Reaction Wheel Component Mode Test Case

Demonstration of the PADRE component assessment mode. This analysis considers a component-centric MADRE 5 spoke reaction wheel model with a steel flywheel. Re-entry is predicted from a circular orbit from 130km altitude using the MADRE version of SESAM. This is enhanced over the current DRAMA 3.0.4 with the inclusion of support for ring primitives, material catalycity and automatic scaling of voxel size. Orbital inclination is selected randomly from a uniform distribution across the full range. An undemisable parent vehicle with a ballistic coefficient randomly selected in the range 50kg/m^2 to 200kg/m^2 is chosen and propagated to a release altitude of between 50km and 100km, at this point the child sub-assembly is released and its various components are propagated to demise or impact. Normal PADRE uncertainties on material properties, heating, drag and atmospheric densities are also applied. A standard Monte-Carlo analysis of 5000 simulations has been executed.

Status

Configuration

Description

The following tables describe the composition of fragments that impact the ground. Separate tables are provided for bands of release altitude. Fragments are listed in order of descending probability of impact. Values for the mean impact magnitude (the expected size of the impact when it occurs), and the mean budget contribution (the expected scale of the impact taking into account the probability of it occurring) are provided.

Release Altitude 50km - 60km

A total of 1075 simulations have been completed with a release altitude in this range. Of these, 1075 (100.0%) resulted in one or more fragments that pose a casualty risk.

Frag# #Impacts Mean Impact Magnitude Impact Probability Mean Budget Contribution Components
Frag Count Casualty (m^2) Mass (kg) Energy (kJ) Frag Count Casualty (m^2) Mass (kg)
1 651 1 2.12 6.98 22.75 60.6% 0.606 0.44 4.23 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT2,RW_STRUT3,RW_STRUT4,RW_STRUT5
2 202 1 2.14 7.08 21.33 18.8% 0.188 0.14 1.33 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_PCB,RW_STRUT1,RW_STRUT2,RW_STRUT3,RW_STRUT4,RW_STRUT5
3 196 1 2.17 8.08 15.09 18.2% 0.182 0.14 1.47 RW_BBU,RW_COVER,RW_FLYWHEEL,RW_MOTOR,RW_PCB,RW_STRUT1,RW_STRUT2,RW_STRUT3,RW_STRUT4,RW_STRUT5
4 25 1 1.70 1.52 5.80 2.3% 0.023 0.01 0.04 RW_BBU,RW_MOTOR
5 25 1 2.07 4.90 14.18 2.3% 0.023 0.02 0.11 RW_FLYWHEEL
6 1 1 2.10 6.50 23.87 0.1% 0.001 0.00 0.01 RW_BBU,RW_FLYWHEEL,RW_MOTOR
7 1 1 2.10 0.02 0.07 0.1% 0.001 0.00 0.00 RW_STRUT1,RW_STRUT5
TOTAL 1101 1.024 0.75 7.19 TOTAL

Release Altitude 60km - 70km

A total of 951 simulations have been completed with a release altitude in this range. Of these, 951 (100.0%) resulted in one or more fragments that pose a casualty risk.

Frag# #Impacts Mean Impact Magnitude Impact Probability Mean Budget Contribution Components
Frag Count Casualty (m^2) Mass (kg) Energy (kJ) Frag Count Casualty (m^2) Mass (kg)
1 496 1 2.07 4.76 12.73 52.2% 0.522 0.37 2.48 RW_FLYWHEEL
2 433 1 2.12 6.91 21.48 45.5% 0.455 0.33 3.15 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT2,RW_STRUT3,RW_STRUT4,RW_STRUT5
3 339 1 1.70 1.40 4.64 35.6% 0.356 0.18 0.50 RW_BBU,RW_MOTOR
4 149 1 1.60 0.63 2.15 15.7% 0.157 0.07 0.10 RW_BBU
5 11 1 2.10 6.51 21.09 1.2% 0.012 0.01 0.08 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT5
6 9 1 2.11 6.50 18.58 0.9% 0.009 0.01 0.06 RW_BBU,RW_FLYWHEEL,RW_MOTOR
7 7 1 2.11 0.04 0.13 0.7% 0.007 0.01 0.00 RW_STRUT1,RW_STRUT3,RW_STRUT4,RW_STRUT5
8 2 1 2.10 0.02 0.07 0.2% 0.002 0.00 0.00 RW_STRUT1,RW_STRUT5
9 1 1 2.14 7.06 18.56 0.1% 0.001 0.00 0.01 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_PCB,RW_STRUT1,RW_STRUT2,RW_STRUT3,RW_STRUT4,RW_STRUT5
10 1 1 2.11 6.53 21.79 0.1% 0.001 0.00 0.01 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT3,RW_STRUT5
11 1 1 2.11 0.00 0.01 0.1% 0.001 0.00 0.00 RW_STRUT4
TOTAL 1449 1.524 0.97 6.38 TOTAL

Release Altitude 70km - 80km

A total of 1002 simulations have been completed with a release altitude in this range. Of these, 1002 (100.0%) resulted in one or more fragments that pose a casualty risk.

Frag# #Impacts Mean Impact Magnitude Impact Probability Mean Budget Contribution Components
Frag Count Casualty (m^2) Mass (kg) Energy (kJ) Frag Count Casualty (m^2) Mass (kg)
1 940 1 2.07 3.67 8.40 93.8% 0.938 0.66 3.44 RW_FLYWHEEL
2 466 1 1.60 0.37 0.92 46.5% 0.465 0.21 0.17 RW_BBU
3 231 1 1.70 1.26 3.76 23.1% 0.231 0.11 0.29 RW_BBU,RW_MOTOR
4 55 1 2.12 6.79 20.45 5.5% 0.055 0.04 0.37 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT2,RW_STRUT3,RW_STRUT4,RW_STRUT5
5 4 1 2.10 6.50 18.04 0.4% 0.004 0.00 0.03 RW_BBU,RW_FLYWHEEL,RW_MOTOR
6 4 1 2.10 0.03 0.08 0.4% 0.004 0.00 0.00 RW_STRUT1,RW_STRUT5
7 2 1 2.10 6.51 18.32 0.2% 0.002 0.00 0.01 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT5
8 1 1 2.11 6.51 19.29 0.1% 0.001 0.00 0.01 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT3,RW_STRUT4
9 1 1 2.11 0.05 0.15 0.1% 0.001 0.00 0.00 RW_STRUT1,RW_STRUT3,RW_STRUT4,RW_STRUT5
TOTAL 1704 1.701 1.03 4.32 TOTAL

Release Altitude 80km - 90km

A total of 991 simulations have been completed with a release altitude in this range. Of these, 985 (99.4%) resulted in one or more fragments that pose a casualty risk.

Frag# #Impacts Mean Impact Magnitude Impact Probability Mean Budget Contribution Components
Frag Count Casualty (m^2) Mass (kg) Energy (kJ) Frag Count Casualty (m^2) Mass (kg)
1 960 1 2.07 2.49 4.52 96.9% 0.969 0.68 2.41 RW_FLYWHEEL
2 284 1 1.60 0.27 0.49 28.7% 0.287 0.13 0.08 RW_BBU
3 98 1 1.70 1.19 3.30 9.9% 0.099 0.05 0.12 RW_BBU,RW_MOTOR
4 20 1 2.12 6.80 20.94 2.0% 0.020 0.01 0.14 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT2,RW_STRUT3,RW_STRUT4,RW_STRUT5
5 4 1 2.10 6.50 18.13 0.4% 0.004 0.00 0.03 RW_BBU,RW_FLYWHEEL,RW_MOTOR
6 4 1 2.10 0.03 0.07 0.4% 0.004 0.00 0.00 RW_STRUT1,RW_STRUT5
7 1 1 2.10 6.51 18.56 0.1% 0.001 0.00 0.01 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT5
TOTAL 1371 1.383 0.88 2.77 TOTAL

Release Altitude 90km - 100km

A total of 981 simulations have been completed with a release altitude in this range. Of these, 973 (99.2%) resulted in one or more fragments that pose a casualty risk.

Frag# #Impacts Mean Impact Magnitude Impact Probability Mean Budget Contribution Components
Frag Count Casualty (m^2) Mass (kg) Energy (kJ) Frag Count Casualty (m^2) Mass (kg)
1 951 1 2.07 2.25 3.91 96.9% 0.969 0.68 2.18 RW_FLYWHEEL
2 255 1 1.60 0.25 0.41 26.0% 0.260 0.11 0.07 RW_BBU
3 79 1 1.70 1.20 3.38 8.1% 0.081 0.04 0.10 RW_BBU,RW_MOTOR
4 18 1 2.12 6.77 20.95 1.8% 0.018 0.01 0.12 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT2,RW_STRUT3,RW_STRUT4,RW_STRUT5
5 2 1 2.11 6.50 19.65 0.2% 0.002 0.00 0.01 RW_BBU,RW_FLYWHEEL,RW_MOTOR
6 1 1 2.11 6.54 21.47 0.1% 0.001 0.00 0.01 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT3,RW_STRUT5
7 1 1 2.10 6.51 21.79 0.1% 0.001 0.00 0.01 RW_BBU,RW_FLYWHEEL,RW_MOTOR,RW_STRUT1,RW_STRUT5
8 1 1 2.11 0.06 0.19 0.1% 0.001 0.00 0.00 RW_STRUT1,RW_STRUT3,RW_STRUT4,RW_STRUT5
9 1 1 2.10 0.03 0.08 0.1% 0.001 0.00 0.00 RW_STRUT1,RW_STRUT5
10 1 1 2.11 0.01 0.02 0.1% 0.001 0.00 0.00 RW_STRUT4
TOTAL 1310 1.335 0.85 2.49 TOTAL

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