6 review of test data indicates conservatism for tile penetration the existing sofi on tile test...

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1 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87 Southwest Research data Crater overpredicted penetration of tile coating significantly • Initial penetration to described by normal velocity Varies with volume/mass of projectile (e.g., 200ft/sec for 3cu. In) • Significant energy is required for the softer SOFI particle to penetrate the relatively hard tile coating Test results do show that it is possible at sufficient mass and velocity • Conversely, once tile is penetrated SOFI can cause significant damage Minor variations in total energy (above penetration level) can cause significant tile damage Flight Condition is significantly outside of test database Volume of ramp is 1920cu in vs 3 cu in for test

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Page 1: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

1

Review of Test Data Indicates Conservatism for Tile Penetration

• The existing SOFI on tile test data used to create Crater was reviewed along with STS-87 Southwest Research data – Crater overpredicted penetration of tile coating

significantly• Initial penetration to described by normal velocity

– Varies with volume/mass of projectile (e.g., 200ft/sec for 3cu. In)

• Significant energy is required for the softer SOFI particle to penetrate the relatively hard tile coating

– Test results do show that it is possible at sufficient mass and velocity

• Conversely, once tile is penetrated SOFI can cause significant damage

– Minor variations in total energy (above penetration level) can cause significant tile damage

– Flight Condition is significantly outside of test database• Volume of ramp is 1920cu in vs 3 cu in for test

Page 2: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

6

Recommend Immediate Visual Inspection of Columbia

• The Crater software can not predict damage to Columbia because the foam piece that hit the ship was big and was travelling very quickly.

• Even tiny foam particles can penetrate the tiles when they strike with sufficient velocity.– Once tiles are penetrated, significant damage to the

spacecraft is possible.

• The foam piece that hit Columbia was 600 times bigger than the foam used to calibrate Crater.– 1920 in3 vs. 3 in3 for test.

• Therefore, as a predictor, Crater is useless in this case.

Page 3: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Recommend Immediate Visual Inspection of Recommend Immediate Visual Inspection of ColumbiaColumbia

The Crater software can not predict damage to Columbia because the foam piece that hit the ship was big and was travelling very quickly.

Even tiny foam particles can penetrate the tiles when they strike with sufficient velocity.◦ Once tiles are penetrated, significant damage to the

spacecraft is possible.The foam piece that hit Columbia was 600

times bigger than the foam used to calibrate Crater.◦ 1920 in3 vs. 3 in3 for test.

Therefore, as a predictor, Crater is useless in this case.

6

Page 4: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

The Crater software can not predict damage to Columbia because the foam piece that hit the ship was big and was travelling very quickly.

Even tiny foam particles can penetrate the tiles when they strike with sufficient velocity.◦ Once tiles are penetrated, significant damage to the

spacecraft is possible. The foam piece that hit Columbia was 600

times bigger than the foam used to calibrate Crater.◦ 1920 in3 vs. 3 in3 for test.

Therefore, as a predictor, Crater is useless in this case.

6

Page 5: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

RECOMMEND IMMEDIATE VISUAL INSPECTION OF COLUMBIA

The Crater software can not predict damage to Columbia because the foam piece that hit the ship was big and was travelling very quickly.

Even tiny foam particles can penetrate the tiles when they strike with sufficient velocity. Once tiles are penetrated, significant damage to the

spacecraft is possible. The foam piece that hit Columbia was 600

times bigger than the foam used to calibrate Crater. 1920 in3 vs. 3 in3 for test.

Therefore, as a predictor, Crater is useless in this case.

6

Page 6: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Recommend Immediate Visual Inspection of Columbia

• The Crater software can not predict damage to Columbia because the foam piece that hit the ship was big and was travelling very quickly.

• Even tiny foam particles can penetrate the tiles when they strike with sufficient velocity.▫ Once tiles are penetrated, significant damage to the

spacecraft is possible.• The foam piece that hit Columbia was 600

times bigger than the foam used to calibrate Crater.▫ 1920 in3 vs. 3 in3 for test.

• Therefore, as a predictor, Crater is useless in this case.

6

Page 7: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Recommend Immediate Visual Inspection of Columbia

The Crater software can not predict damage to Columbia because the foam piece that hit the ship was big and was travelling very quickly.

Even tiny foam particles can penetrate the tiles when they strike with sufficient velocity. Once tiles are penetrated, significant damage to the

spacecraft is possible. The foam piece that hit Columbia was 600

times bigger than the foam used to calibrate Crater. 1920 in3 vs. 3 in3 for test.

Therefore, as a predictor, Crater is useless in this case.

6

Page 8: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

The Crater software can not predict damage to Columbia because the foam piece that hit the ship was big and was travelling very quickly.

Even tiny foam particles can penetrate the tiles when they strike with sufficient velocity.› Once tiles are penetrated, significant damage to the

spacecraft is possible. The foam piece that hit Columbia was 600

times bigger than the foam used to calibrate Crater.› 1920 in3 vs. 3 in3 for test.

Therefore, as a predictor, Crater is useless in this case.

6

Page 9: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Recommend Immediate Visual Inspection of Columbia

The Crater software can not predict damage to Columbia because the foam piece that hit the ship was big and was travelling very quickly.

Even tiny foam particles can penetrate the tiles when they strike with sufficient velocity. Once tiles are penetrated, significant damage to the

spacecraft is possible. The foam piece that hit Columbia was 600 times

bigger than the foam used to calibrate Crater. 1920 in3 vs. 3 in3 for test.

Therefore, as a predictor, Crater is useless in this case.

6

Page 10: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87
Page 11: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Recommend Immediate Visual Inspection of Columbia

6

Sample damage from a very small foam hit

Size of foam that hit Columbia is 600 times bigger

Page 12: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Recommend Immediate Visual Inspection of Columbia

6

Sample damage from a very small foam hit

Size of foam that hit Columbia is 600 times bigger

Page 13: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Recommend Immediate Visual Inspection of Columbia

6

Sample damage from a very small “dime size” foam hit

Size of foam that hit Columbia is 600 times bigger

Recommend Immediate Visual Inspection of Columbia

Page 14: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Recommend Immediate Visual Inspection of Columbia

6

Sample damage from a very small “dime size” foam hit

Size of foam that hit Columbia is 600 times bigger

Recommend Immediate Visual Inspection of Columbia

Page 15: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87
Page 16: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Recommend Immediate Visual Inspection of Columbia

6

Sample damage from a very small “dime size” foam hit

Size of foam that hit Columbia is 600 times bigger

Recommend Immediate Visual Inspection of Columbia

Page 17: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Need to Inspect Columbia!

The Crater software can not predict damage to Columbia

6

The foam piece that hit Columbia was 600 times bigger than the foam hits used to calibrate Crater.

Page 18: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87

Need to Inspect Columbia!

The Crater software can not predict damage to Columbia

6

The foam piece that hit Columbia was 600 times bigger than the foam hits used to calibrate Crater.

Page 19: 6 Review of Test Data Indicates Conservatism for Tile Penetration The existing SOFI on tile test data used to create Crater was reviewed along with STS-87