Effect of the FlashJet Paint Removal System on 

Rotor Blade Skin Materials 

by Scott Grendahl 

ARL-TR-4003 December 2006 

Approved for public release; distribution is unlimited. 
NOTICES 

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The findings in this report are not to be construed as an official Department of the Army position unless 

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Citation of manufacturer’s or trade names does not constitute an official endorsement or approval of the 

use thereof. 

Destroy this report when it is no longer needed. Do not return it to the originator. 
Army Research Laboratory 

Aberdeen Proving Ground, MD 21005-5069 

ARL-TR-4003 December 2006 

Effect of the FlashJet Paint Removal System on 

Rotor Blade Skin Materials 

Scott Grendahl 

Weapons and Materials Research Directorate, ARL 

Approved for public release; distribution is unlimited. 
ii

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1. REPORT DATE (DD-MM-YYYY)

December 2006 

2. REPORT TYPE 

Final 

3. DATES COVERED (From - To) 

1 June 2005–1 April 2006 

5a. CONTRACT NUMBER 

5b. GRANT NUMBER 

4. TITLE AND SUBTITLE 

Effect of the FlashJet Paint Removal System on Rotor Blade Skin Materials 

5c. PROGRAM ELEMENT NUMBER 

5d. PROJECT NUMBER 

M042-483L31 

5e. TASK NUMBER 

6. AUTHOR(S) 

Scott Grendahl 

5f. WORK UNIT NUMBER 

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 

U.S. Army Research Laboratory 

ATTN: AMSRD-ARL-WM-MC 

Aberdeen Proving Ground, MD 21005-5069 

8. PERFORMING ORGANIZATION 

 REPORT NUMBER 

ARL-TR-4003 

10. SPONSOR/MONITOR'S ACRONYM(S) 

AMCOM 

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 

U.S. Army Aviation and Missile Command 

Redstone Arsenal, AL 35898 11. SPONSOR/MONITOR'S REPORT 

 NUMBER(S) 

12. DISTRIBUTION/AVAILABILITY STATEMENT 

Approved for public release; distribution is unlimited. 

13. SUPPLEMENTARY NOTES 

14. ABSTRACT 

The U.S. Army Aviation and Missile Research, Development, and Engineering Command in Huntsville, AL, requested the U.S. 

Army Research Laboratory Weapons and Materials Research Directorate at Aberdeen Proving Ground, MD, to develop and 

execute a program aimed at evaluating the effect of the FlashJet coating removal system on the mechanical properties of the 

typical U.S. Army aviation blade skin materials. The skin materials representative of the three most common U.S. Army 

helicopters were assessed. Fatigue, tensile, and short-beam shear tests were conducted. Test panels from six specimen groups 

were evaluated: baseline (as-painted), hand-sanded, stripped-to-primer, stripped-to-substrate, stripped-to-substrate plus two 

additional passes, and lifecycle. 

15. SUBJECT TERMS

FlashJet, rotor blade composite, mechanical properties 

16. SECURITY CLASSIFICATION OF: 

19a. NAME OF RESPONSIBLE PERSON

Scott Grendahl 

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UNCLASSIFIED 

b. ABSTRACT 

UNCLASSIFIED

c. THIS PAGE 

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OF PAGES 

36 

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410-306-0819 

Standard Form 298 (Rev. 8/98) 

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iii

Contents 

List of Figures iv

List of Tables v

1. Objective 1

2. Materials 1

3. Experimental Procedure 1

4. Results 2

4.1 Short-Beam Shear............................................................................................................2 

4.2 Tensile Testing ..............................................................................................................14 

4.3 Fatigue Testing..............................................................................................................14 

5. Discussion 24

5.1 Short-Beam Shear..........................................................................................................24 

5.2 Tensile Testing ..............................................................................................................24 

5.3 Fatigue Testing..............................................................................................................24 

6. Conclusions 25

7. References 26

Distribution List 27 
iv

List of Figures 

Figure 1. As-received 5216 E glass panel A..................................................................................3

Figure 2. As-received 5216 E glass panel B...................................................................................3

Figure 3. As-received 5216 E glass panel C..................................................................................4

Figure 4. As-received 5216 E glass panel D...................................................................................4

Figure 5. As-received 5216 E glass panel E. ..................................................................................5

Figure 6. As-received 5216 E glass panel F. ..................................................................................5

Figure 7. As-received 5216 S glass panel A...................................................................................6

Figure 8. As-received 5216 S glass panel B. ..................................................................................6

Figure 9. As-received 5216 S glass panel C. ..................................................................................7

Figure 10. As-received 5216 S glass panel D.................................................................................7 

Figure 11. As-received 5216 S glass panel E. ................................................................................8 

Figure 12. As-received 5216 S glass panel F..................................................................................8

Figure 13. As-received 114 E glass panel A...................................................................................9

Figure 14. As-received 114 E glass panel B...................................................................................9

Figure 15. As-received 114 E glass panel C.................................................................................10 

Figure 16. As-received 114 E glass panel D.................................................................................10 

Figure 17. As-received 114 E glass panel E. ................................................................................11 

Figure 18. As-received 114 E glass panel F. ................................................................................11 

Figure 19. Short-beam shear test results for 5216 E glass............................................................12 

Figure 20. Short-beam shear test results for 5216 S glass. ...........................................................12 

Figure 21. Short-beam shear test results for 114 E glass..............................................................13 

Figure 22. Tensile test results for 5216 E glass. ...........................................................................14

Figure 23. Tensile test results for 5216 S glass. ...........................................................................15

Figure 24. Tensile test results for 114 E glass. .............................................................................15 

Figure 25. Fatigue test results for 5216 E glass............................................................................16

Figure 26. Fatigue test results for 5216 S glass. ...........................................................................17

Figure 27. Fatigue test results for 114 E glass..............................................................................17 
v

List of Tables 

Table 1. Composite materials. ........................................................................................................1 

Table 2. Composite test groups.......................................................................................................2 

Table 3. Short-beam shear results.................................................................................................13 

Table 4. Tensile testing results......................................................................................................16 

Table 5. Fatigue results for 5216 E glass......................................................................................18 

Table 6. Fatigue results for 5216 S glass. .....................................................................................20 

Table 7. Fatigue results for 114 E glass........................................................................................22 
vi

INTENTIONALLY LEFT BLANK.
1

1. Objective 

The objective of this study was to assess the effect of the FlashJet coating removal system on the 

mechanical properties of U.S. Army aviation blade skin materials.

2. Materials 

The materials utilized within this work were representative of the materials used in the 

manufacture of the rotor blades from the CH-47 Chinook, the AH-64 Apache, and the UH-60 

Blackhawk. Table 1 depicts the materials utilized within this work.

Table 1. Composite materials. 

Platform Material Lay-up Material Specification 

CH-47 E-glass/5216 from Cytec, 

Anaheim, CA 

2 plies, ±45° BMS8-196, Type III, Class A, 

Grade 1 (1) 

AH-64 S-2 Glass/5216 from Cytec, 

Anaheim, CA 

0/90/0°, 0° in spar direction HMS 16-1113, Type 1 (2) 

UH-60 E-glass/Cycom 114 from Cytec, 

Greenville, TX (Cycom 114/1062 

W462 24 in E-glass) 

(90/–30/30)s SS9610-001 CYCOM 114, 1 

sheet 24 × 24 in (3) 

The coating system applied to the composite panels consisted of MIL-P-23377 (4) primer to a 

dry film thickness (DFT) of 0.0010–0.0015 in and MIL-P-46168 (5) top coat to a DFT of 

0.0020–0.0025 in. The coating system was air dried for one week and then baked at 150 °F for 1 

week to insure adequate curing. 

3. Experimental Procedure 

Composite panels were manufactured in accordance with the lay-up in table 1. All panels were 

cured via autoclave in accordance with the manufacturer’s recommendations and governing 

documentation. The panels were painted and cured at Corpus Christi Army Depot (CCAD). 

CCAD processed the panels via the on-site FlashJet system and hand-sanding process in 

accordance with table 2. 
2

Table 2. Composite test groups. 

Process Material Process Notes 

Group A 

Hand-sanding 

5216 E glass 

5216 S glass 

114 E glass 

Manual hand-sanding process by CCAD 

personnel in the composite shop. 

Group B 

As-painted 

5216 E glass 

5216 S glass 

114 E glass 

Tested in the as-painted condition. 

Group C 

Stripped to primer 

5216 E glass 

5216 S glass 

114 E glass 

Utilized FlashJet to remove just the 

topcoat. 

Group D 

Stripped to substrate 

5216 E glass 

5216 S glass 

114 E glass 

Utilized FlashJet to remove both the 

topcoat and primer. 

Group E 

Stripped to substrate plus two additional 

passes. 

5216 E glass 

5216 S glass 

114 E glass 

Utilized FlashJet to remove both paint 

layers and then two additional passes 

under the same conditions. 

Group F 

Lifecycle—stripped and re-painted five 

times. 

5216 E glass 

5216 S glass 

114 E glass 

Utilized FlashJet to remove both paint 

layers then re-painting for five 

iterations. 

The parameters of the FlashJet process were approximately 2000 V, 1 in/s travel speed, and 4-Hz 

xenon bulb frequency. In some cases, the voltage was slightly increased when removal was not 

fully achieved. The stripped panels were shipped to the U. S. Army Research Laboratory from 

CCAD for sectioning and mechanical testing. The as-received panels utilized for testing are 

presented in figures 1–18. The panels are also shown in their sectioned state in these figures.

The mechanical testing performed included tensile testing, fatigue testing, and short beam shear 

testing. These tests were conducted in accordance with the ASTM standards, ASTM-D-3039 

(6), ASTM-D-3479 (7), and ASTM-D-2344 (8), respectively. The edges were polished through 

1200-grit SiC paper to assist in individual ply observation. Tensile and short-beam shear testing 

were conducted at 0.05 in/min. Fatigue testing was conducted at 20 Hz and at R = 0.1. 

4. Results 

4.1 Short-Beam Shear 

The short-beam shear results are presented in figures 19–21 and also tabulated in table 3. The 

“baseline” and “stripped-to-primer” groups had the highest short-beam shear strength values 

during the testing. In general, the “hand-sanded” group had the lowest strength values. 
3

Figure 1. As-received 5216 E glass panel A. 

Figure 2. As-received 5216 E glass panel B. 
4

Figure 3. As-received 5216 E glass panel C. 

Figure 4. As-received 5216 E glass panel D. 
5

Figure 5. As-received 5216 E glass panel E. 

Figure 6. As-received 5216 E glass panel F. 
6

Figure 7. As-received 5216 S glass panel A. 

Figure 8. As-received 5216 S glass panel B. 
7

Figure 9. As-received 5216 S glass panel C. 

Figure 10. As-received 5216 S glass panel D. 
8

Figure 11. As-received 5216 S glass panel E. 

Figure 12. As-received 5216 S glass panel F.
9

Figure 13. As-received 114 E glass panel A. 

Figure 14. As-received 114 E glass panel B. 
10

Figure 15. As-received 114 E glass panel C. 

Figure 16. As-received 114 E glass panel D. 
11

Figure 17. As-received 114 E glass panel E. 

Figure 18. As-received 114 E glass panel F. 
12

5216 E Glass SBS

800

900

1000

1100

1200

1300

1400

1 2 3 4 5 6 7 8 9 10

Specimen #

Short Beam Strength (psi)

Baseline As-Painted

Hand Sanded

Stripped to Primer

Stripped to Substrate

Stripped to Substrate +2

Lifecycle

Figure 19. Short-beam shear test results for 5216 E glass. 

5216 S Glass SBS 

800

900

1000

1100

1200

1300

1400

1 2 3 4 5 6 7 8 9 10

Specimen #

Short Beam Strength (psi)

Baseline As-Painted

Hand Sanded

Stripped to Primer

Stripped to Substrate

Stripped to Substrate +2

Lifecycle

Figure 20. Short-beam shear test results for 5216 S glass.
13

114 E Glass SBS

800

900

1000

1100

1200

1300

1400

1 2 3 4 5 6 7 8 9 10

Specimen #

Short Beam Strength (psi)

Baseline-As-Painted

Hand Sanded

Stripped to Primer

Stripped to Substrate

Stripped to Substrate +2

Lifecycle

Figure 21. Short-beam shear test results for 114 E glass. 

Table 3. Short-beam shear results. 

Material Test Group Average Short Beam Shear Strength 

(PSI) 

Standard Deviation

5216 E Glass Baseline as-painted 1006.3 27.4 

5216 E Glass Hand sanded 910 47.6 

5216 E Glass Stripped to primer 1039.4 44.9 

5216 E Glass Stripped to substrate 891.6 37.4 

5216 E Glass Stripped to substrate plus two 951.2 28.8 

5216 E Glass Lifecycle 934.8 25.7 

5216 S Glass Baseline as-painted 1136 21.5 

5216 S Glass Hand sanded 1046 43.0 

5216 S Glass Stripped to primer 1128 31.5 

5216 S Glass Stripped to substrate 1114.4 28.1 

5216 S Glass Stripped to substrate plus two 1129.5 18.8 

5216 S Glass Lifecycle 1128.2 28.4 

114 E Glass Baseline as-painted 1131.4 15.0 

114 E Glass Hand sanded 972.5 19.3 

114 E Glass Stripped to primer 1143.1 29.6 

114 E Glass Stripped to substrate 1059.4 8.9 

114 E Glass Stripped to substrate plus two 1113.7 10.7 

114 E Glass Lifecycle 1068.1 11.9 
14

4.2 Tensile Testing 

The tensile results are presented in figures 22–24 and also tabulated in table 4. Generally, the 

“baseline” and “stripped-to-primer” groups had the highest tensile values observed, and the 

“hand-sanded” group had the lowest strength values. 

4.3 Fatigue Testing 

The fatigue results are presented in figures 25–27 and in tabular form in tables 5–7. It can be 

observed in the data that the “baseline” and “stripped-to-primer” groups performed the best 

under the applied fatigue stresses. The “stripped-to-substrate plus two” and “lifecycle” groups 

were the poorest performers under these conditions. 

5216 E Glass Tensile Data

20000

22000

24000

26000

28000

30000

32000

0123456

Specimen #

Stress (PSI)

5216 E Glass Baseline

5216 E Glass Hand Sanded

5216 E Glass To Primer

5216 E Glass To Substrate

5216 E Glass To Substrate +2

5216 E Glass Lifecycle

Figure 22. Tensile test results for 5216 E glass. 
15

5216 S Glass Tensile Data

80000

85000

90000

95000

100000

105000

110000

115000

0123456

Specimen #

Stress (PSI)

5216 S Glass Baseline

5216 S Glass Hand Sanded

5216 S Glass To Primer

5216 S Glass To Substrate

5216 S Glass To Substrate +2

5216 S Glass Lifecycle

Figure 23. Tensile test results for 5216 S glass. 

114 E Glass Tensile Data

25000

30000

35000

40000

45000

50000

55000

60000

65000

0123456

Specimen #

Stress (PSI)

114 E Glass Baseline

114 Hand Sanded

114 To Primer

114 To Substrate

114 To Substrate +2

114 Lifecycle

Figure 24. Tensile test results for 114 E glass. 
16

Table 4. Tensile testing results. 

Material Test Group Average Tensile Strength 

(PSI) 

Standard Deviation

5216 E Glass Baseline as-painted 30224 157 

5216 E Glass Hand sanded 23295 1323 

5216 E Glass Stripped to primer 27461 319 

5216 E Glass Stripped to substrate 26170 373 

5216 E Glass Stripped to substrate plus two 25545 63 

5216 E Glass Lifecycle 26355 52 

5216 S Glass Baseline as-painted 109487 140 

5216 S Glass Hand sanded 96237 1256 

5216 S Glass Stripped to primer 104802 1533 

5216 S Glass Stripped to substrate 103284 2782 

5216 S Glass Stripped to substrate plus two 101168 1519 

5216 S Glass Lifecycle 102174 3315 

114 E Glass Baseline as-painted 50371 2330 

114 E Glass Hand sanded 37277 3489 

114 E Glass Stripped to primer 40984 4038 

114 E Glass Stripped to substrate 42666 2449 

114 E Glass Stripped to substrate plus two 34200 1013 

114 E Glass Lifecycle 41309 1935 

FlashJet 5216 E Glass 

Maximum Stress versus Cycles to Failure

9.00

10.00

11.00

12.00

13.00

14.00

15.00

16.00

1.E+03 1.E+04 1.E+05 1.E+06 1.E+07

Cycles to Failure, N

Maximum Stress, KSI

5216 E Baseline Painted

5216 E Hand Sanded

5216 E Stripped to Primer

5216 E Stripped to Substrate

5216 E Stripped to Substrate+2

5216 E Lifecycle

Figure 25. Fatigue test results for 5216 E glass. 
17

FlashJet 5216 S Glass 

Maximum Stress versus Cycles to Failure

35.00

36.00

37.00

38.00

39.00

40.00

41.00

42.00

43.00

44.00

45.00

1.E+03 1.E+04 1.E+05 1.E+06 1.E+07

Cycles to Failure, N

Maximum Stress, KSI

5216 S Baseline Painted

5216 S Hand Sanded

5216 S To Primer

5216 S To Substrate

5216 S To Substrate+2

5216 S Lifecycle

Figure 26. Fatigue test results for 5216 S glass. 

FlashJet 114 E Glass 

Maximum Stress versus Cycles to Failure

16.00

18.00

20.00

22.00

24.00

26.00

28.00

30.00

32.00

1.E+03 1.E+04 1.E+05 1.E+06 1.E+07

Cycles to Failure, N

Maximum Stress, KSI

114 E Baseline Painted

114 E Hand Sanded

114 E To Primer

114 E To Substrate

114 E Substrate +2

114 E Lifecycle

Figure 27. Fatigue test results for 114 E glass. 
18

Table 5. Fatigue results for 5216 E glass. 

Specimen 

No. Material Group 

Max 

Stress 

(KSI) 

Mean 

Stress 

(KSI) 

Min 

Stress 

(KSI) 

Stress 

Amplitude 

(KSI) 

R-Value Cycles 

5E-B2 5216 E Baseline — 0.000 0.0 0.0 — — 

5E-B3 5216 E Baseline 15.00 8.250 1.5 6.8 0.1 1,490 

5E-B4 5216 E Baseline 9.50 5.225 1.0 4.3 0.1 1,300,000 

5E-B6 5216 E Baseline 11.50 6.325 1.2 5.2 0.1 45,642 

5E-B7 5216 E Baseline 11.50 6.325 1.2 5.2 0.1 55,676 

5E-B8 5216 E Baseline 13.00 7.150 1.3 5.9 0.1 7,762 

5E-B10 5216 E Baseline 10.50 5.775 1.1 4.7 0.1 248,330 

5E-B11 5216 E Baseline 12.00 6.600 1.2 5.4 0.1 30,226 

5E-B12 5216 E Baseline 12.00 6.600 1.2 5.4 0.1 32,000 

5E-B13 5216 E Baseline 10.00 5.500 1.0 4.5 0.1 603,920 

5E-B15 5216 E Baseline 10.00 5.500 1.0 4.5 0.1 650,843 

5E-B16 5216 E Baseline 11.00 6.050 1.1 5.0 0.1 99,119 

5E-B17 5216 E Baseline 11.00 6.050 1.1 5.0 0.1 114,909 

5E-B19 5216 E Baseline 12.50 6.875 1.3 5.6 0.1 11,233 

5E-B20 5216 E Baseline 10.50 5.775 1.1 4.7 0.1 191,944 

5E-A1 5216 E Hand sanded 13.00 7.150 1.3 5.9 0.1 7,156 

5E-A2 5216 E Hand sanded 12.50 6.875 1.3 5.6 0.1 11,657 

5E-A3 5216 E Hand sanded 12.50 6.875 1.3 5.6 0.1 15,784 

5E-A4 5216 E Hand sanded 12.00 6.600 1.2 5.4 0.1 20,494 

5E-A5 5216 E Hand sanded 12.00 6.600 1.2 5.4 0.1 13,807 

5E-A6 5216 E Hand sanded 11.50 6.325 1.2 5.2 0.1 32,016 

5E-A7 5216 E Hand sanded 11.50 6.325 1.2 5.2 0.1 30,621 

5E-A8 5216 E Hand sanded 11.00 6.050 1.1 5.0 0.1 55,399 

5E-A11 5216 E Hand sanded 11.00 6.050 1.1 5.0 0.1 62,931 

5E-A12 5216 E Hand sanded 10.50 5.775 1.1 4.7 0.1 208,420 

5E-A13 5216 E Hand sanded 10.50 5.775 1.1 4.7 0.1 180,432 

5E-A14 5216 E Hand sanded 10.00 5.500 1.0 4.5 0.1 358,859 

5E-A16 5216 E Hand sanded 10.00 5.500 1.0 4.5 0.1 452,986 

5E-A17 5216 E Hand sanded 9.50 5.225 1.0 4.3 0.1 826,419 

5E-A18 5216 E Hand sanded 9.50 5.225 1.0 4.3 0.1 874,591 

5E-C1 5216 E To primer 13.00 7.150 1.3 5.9 0.1 9,402 

5E-C3 5216 E To primer 12.50 6.875 1.3 5.6 0.1 14,244 

5E-C4 5216 E To primer 12.50 6.875 1.3 5.6 0.1 12,896 

5E-C5 5216 E To primer 12.00 6.600 1.2 5.4 0.1 30,142 

5E-C6 5216 E To primer 12.00 6.600 1.2 5.4 0.1 37,831 

5E-C7 5216 E To primer 11.50 6.325 1.2 5.2 0.1 56,899 

5E-C8 5216 E To primer 11.50 6.325 1.2 5.2 0.1 57,018 

5E-C9 5216 E To primer 11.00 6.050 1.1 5.0 0.1 109,187 

5E-C10 5216 E To primer 11.00 6.050 1.1 5.0 0.1 118,462 

5E-C11 5216 E To primer 10.50 5.775 1.1 4.7 0.1 241,980 

5E-C13 5216 E To primer 10.50 5.775 1.1 4.7 0.1 248,919 

5E-C16 5216 E To primer 10.00 5.500 1.0 4.5 0.1 623,713 

5E-C17 5216 E To primer 10.00 5.500 1.0 4.5 0.1 606,532 

5E-C18 5216 E To primer 9.50 5.225 1.0 4.3 0.1 1,072,564 

5E-C19 5216 E To primer 9.50 5.225 1.0 4.3 0.1 999,311 

5E-D1 5216 E To substrate 13.00 7.150 1.3 5.9 0.1 7,894 

5E-D3 5216 E To substrate 12.50 6.875 1.3 5.6 0.1 13,038 
19

Table 5. Fatigue results for 5216 E glass (continued). 

Specimen 

No. Material Group 

Max 

Stress 

(KSI) 

Mean 

Stress 

(KSI) 

Min 

Stress 

(KSI) 

Stress 

Amplitude 

(KSI) 

R-Value Cycles 

5E-D4 5216 E To substrate 12.50 6.875 1.3 5.6 0.1 14,062 

5E-D5 5216 E To substrate 12.00 6.600 1.2 5.4 0.1 30,493 

5E-D6 5216 E To substrate 12.00 6.600 1.2 5.4 0.1 24,285 

5E-D7 5216 E To substrate 11.50 6.325 1.2 5.2 0.1 51,139 

5E-D8 5216 E To substrate 11.50 6.325 1.2 5.2 0.1 54,183 

5E-D9 5216 E To substrate 11.00 6.050 1.1 5.0 0.1 86,582 

5E-D10 5216 E To substrate 11.00 6.050 1.1 5.0 0.1 112,272 

5E-D11 5216 E To substrate 10.50 5.775 1.1 4.7 0.1 179,155 

5E-D12 5216 E To substrate 10.50 5.775 1.1 4.7 0.1 169,898 

5E-D14 5216 E To substrate 10.00 5.500 1.0 4.5 0.1 524,376 

5E-D15 5216 E To substrate 10.00 5.500 1.0 4.5 0.1 465,435 

5E-D18 5216 E To substrate 9.50 5.225 1.0 4.3 0.1 835,426 

5E-D19 5216 E To substrate 9.50 5.225 1.0 4.3 0.1 919,256 

5E-E1 5216 E To substrate +2 13.00 7.150 1.3 5.9 0.1 7,118 

5E-E2 5216 E To substrate +2 12.50 6.875 1.3 5.6 0.1 14,155 

5E-E3 5216 E To substrate +2 12.50 6.875 1.3 5.6 0.1 11,315 

5E-E4 5216 E To substrate +2 12.00 6.600 1.2 5.4 0.1 25,100 

5E-E5 5216 E To substrate +2 12.00 6.600 1.2 5.4 0.1 32,158 

5E-E7 5216 E To substrate +2 11.50 6.325 1.2 5.2 0.1 49,878 

5E-E11 5216 E To substrate +2 11.50 6.325 1.2 5.2 0.1 46,302 

5E-E12 5216 E To substrate +2 11.00 6.050 1.1 5.0 0.1 77,906 

5E-E13 5216 E To substrate +2 11.00 6.050 1.1 5.0 0.1 74,152 

5E-E14 5216 E To substrate +2 10.50 5.775 1.1 4.7 0.1 97,016 

5E-E15 5216 E To substrate +2 10.50 5.775 1.1 4.7 0.1 124,767 

5E-E16 5216 E To substrate +2 10.00 5.500 1.0 4.5 0.1 357,130 

5E-E17 5216 E To substrate +2 10.00 5.500 1.0 4.5 0.1 449,304 

5E-E18 5216 E To substrate +2 9.50 5.225 1.0 4.3 0.1 758,426 

5E-E19 5216 E To substrate +2 9.50 5.225 1.0 4.3 0.1 695,851 

5E-F2 5216 S Lifecycle 9.50 5.225 1.0 4.3 0.1 765,842 

5E-F4 5216 S Lifecycle 9.50 5.225 1.0 4.3 0.1 621,916 

5E-F5 5216 S Lifecycle 10.00 5.500 1.0 4.5 0.1 191,919 

5E-F6 5216 S Lifecycle 10.00 5.500 1.0 4.5 0.1 174,089 

5E-F7 5216 S Lifecycle 10.50 5.775 1.1 4.7 0.1 95,189 

5E-F9 5216 S Lifecycle 10.50 5.775 1.1 4.7 0.1 86,824 

5E-F10 5216 S Lifecycle 11.00 6.050 1.1 5.0 0.1 61,284 

5E-F11 5216 S Lifecycle 11.00 6.050 1.1 5.0 0.1 54,220 

5E-F12 5216 S Lifecycle 11.50 6.325 1.2 5.2 0.1 41,524 

5E-F14 5216 S Lifecycle 11.50 6.325 1.2 5.2 0.1 31,582 

5E-F15 5216 S Lifecycle 12.00 6.600 1.2 5.4 0.1 15,987 

5E-F16 5216 S Lifecycle 12.00 6.600 1.2 5.4 0.1 12,568 

5E-F17 5216 S Lifecycle 12.50 6.875 1.3 5.6 0.1 11,123 

5E-F18 5216 S Lifecycle 12.50 6.875 1.3 5.6 0.1 10,524 

5E-F20 5216 S Lifecycle 13.00 7.150 1.3 5.9 0.1 5,619 
20

Table 6. Fatigue results for 5216 S glass. 

Specimen 

No. Material Group 

Max 

Stress 

(KSI) 

Mean 

Stress 

(KSI) 

Min 

Stress 

(KSI) 

Stress 

Amplitude 

(KSI) 

R-Value Cycles 

5S-B1 5216 S Baseline 50.00 27.500 5.0 45.0 0.1 — 

5S-B2 5216 S Baseline 38.00 20.900 3.8 34.2 0.1 243,544 

5S-B3 5216 S Baseline 38.00 20.900 3.8 34.2 0.1 322,251 

5S-B4 5216 S Baseline 39.00 21.450 3.9 35.1 0.1 82,566 

5S-B5 5216 S Baseline 39.00 21.450 3.9 35.1 0.1 63,854 

5S-B8 5216 S Baseline 40.00 22.000 4.0 36.0 0.1 26,020 

5S-B9 5216 S Baseline 40.00 22.000 4.0 36.0 0.1 36,575 

5S-B10 5216 S Baseline 41.00 22.550 4.1 36.9 0.1 20,345 

5S-B11 5216 S Baseline 41.00 22.550 4.1 36.9 0.1 34,740 

5S-B12 5216 S Baseline 42.00 23.100 4.2 37.8 0.1 17,006 

5S-B14 5216 S Baseline 42.00 23.100 4.2 37.8 0.1 15,986 

5S-B15 5216 S Baseline 37.00 20.350 3.7 33.3 0.1 824,466 

5S-B16 5216 S Baseline 37.00 20.350 3.7 33.3 0.1 695,996 

5S-B17 5216 S Baseline 44.00 24.200 4.4 39.6 0.1 4,296 

5S-B18 5216 S Baseline 44.00 24.200 4.4 39.6 0.1 6,808 

5S-A1 5216 S Hand sanded 36.00 19.800 3.6 32.4 0.1 740,876 

5S-A3 5216 S Hand sanded 38.00 20.900 3.8 34.2 0.1 146,592 

5S-A4 5216 S Hand sanded 38.00 20.900 3.8 34.2 0.1 270,658 

5S-A5 5216 S Hand sanded 39.00 21.450 3.9 35.1 0.1 57,628 

5S-A6 5216 S Hand sanded 39.00 21.450 3.9 35.1 0.1 78,683 

5S-A7 5216 S Hand sanded 40.00 22.000 4.0 36.0 0.1 35,492 

5S-A8 5216 S Hand sanded 40.00 22.000 4.0 36.0 0.1 34,447 

5S-A9 5216 S Hand sanded 41.00 22.550 4.1 36.9 0.1 22,994 

5S-A10 5216 S Hand sanded 41.00 22.550 4.1 36.9 0.1 20,450 

5S-A12 5216 S Hand sanded 42.00 23.100 4.2 37.8 0.1 19,153 

5S-A14 5216 S Hand sanded 42.00 23.100 4.2 37.8 0.1 12,825 

5S-A16 5216 S Hand sanded 37.00 20.350 3.7 33.3 0.1 387,260 

5S-A17 5216 S Hand sanded 37.00 20.350 3.7 33.3 0.1 350,569 

5S-A18 5216 S Hand sanded 44.00 24.200 4.4 39.6 0.1 4,345 

5S-A19 5216 S Hand sanded 44.00 24.200 4.4 39.6 0.1 3,505 

5S-C1 5216 S To primer 36.00 19.800 3.6 32.4 0.1 1,419,454 

5S-C2 5216 S To primer 37.00 20.350 3.7 33.3 0.1 704,151 

5S-C3 5216 S To primer 37.00 20.350 3.7 33.3 0.1 730,543 

5S-C4 5216 S To primer 38.00 20.900 3.8 34.2 0.1 294,672 

5S-C5 5216 S To primer 38.00 20.900 3.8 34.2 0.1 259,642 

5S-C7 5216 S To primer 39.00 21.450 3.9 35.1 0.1 60,044 

5S-C8 5216 S To primer 39.00 21.450 3.9 35.1 0.1 73,424 

5S-C9 5216 S To primer 40.00 22.000 4.0 36.0 0.1 34,568 

5S-C10 5216 S To primer 40.00 22.000 4.0 36.0 0.1 29,134 

5S-C11 5216 S To primer 41.00 22.550 4.1 36.9 0.1 25,034 

5S-C12 5216 S To primer 41.00 22.550 4.1 36.9 0.1 28,743 

5S-C13 5216 S To primer 42.00 23.100 4.2 37.8 0.1 15,314 

5S-C14 5216 S To primer 42.00 23.100 4.2 37.8 0.1 13,365 

5S-C15 5216 S To primer 44.00 24.200 4.4 39.6 0.1 5,631 

5S-C19 5216 S To primer 44.00 24.200 4.4 39.6 0.1 6,305 

5S-D3 5216 S To substrate 36.00 19.800 3.6 32.4 0.1 370,301 
21

Table 6. Fatigue results for 5216 S glass (continued). 

Specimen 

No. Material Group 

Max 

Stress 

(KSI) 

Mean 

Stress 

(KSI) 

Min 

Stress 

(KSI) 

Stress 

Amplitude 

(KSI) 

R-Value Cycles 

5S-D4 5216 S To substrate 37.00 20.350 3.7 33.3 0.1 256,542 

5S-D5 5216 S To substrate 37.00 20.350 3.7 33.3 0.1 220,417 

5S-D6 5216 S To substrate 38.00 20.900 3.8 34.2 0.1 133,269 

5S-D7 5216 S To substrate 38.00 20.900 3.8 34.2 0.1 109,363 

5S-D8 5216 S To substrate 39.00 21.450 3.9 35.1 0.1 54,524 

5S-D9 5216 S To substrate 39.00 21.450 3.9 35.1 0.1 61,040 

5S-D10 5216 S To substrate 40.00 22.000 4.0 36.0 0.1 22,315 

5S-D11 5216 S To substrate 40.00 22.000 4.0 36.0 0.1 27,971 

5S-D12 5216 S To substrate 41.00 22.550 4.1 36.9 0.1 21,168 

5S-D15 5216 S To substrate 41.00 22.550 4.1 36.9 0.1 23,330 

5S-D17 5216 S To substrate 42.00 23.100 4.2 37.8 0.1 12,185 

5S-D18 5216 S To substrate 42.00 23.100 4.2 37.8 0.1 11,647 

5S-D19 5216 S To substrate 44.00 24.200 4.4 39.6 0.1 5,625 

5S-D20 5216 S To substrate 44.00 24.200 4.4 39.6 0.1 4,253 

5S-E5 5216 S To substrate +2 36.00 19.800 3.6 32.4 0.1 375,054 

5S-E7 5216 S To substrate +2 37.00 20.350 3.7 33.3 0.1 198,862 

5S-E8 5216 S To substrate +2 37.00 20.350 3.7 33.3 0.1 196,465 

5S-E9 5216 S To substrate +2 38.00 20.900 3.8 34.2 0.1 63,034 

5S-E10 5216 S To substrate +2 38.00 20.900 3.8 34.2 0.1 95,687 

5S-E11 5216 S To substrate +2 39.00 21.450 3.9 35.1 0.1 41,212 

5S-E12 5216 S To substrate +2 39.00 21.450 3.9 35.1 0.1 27,043 

5S-E13 5216 S To substrate +2 40.00 22.000 4.0 36.0 0.1 17,586 

5S-E14 5216 S To substrate +2 40.00 22.000 4.0 36.0 0.1 21,301 

5S-E15 5216 S To substrate +2 41.00 22.550 4.1 36.9 0.1 15,420 

5S-E16 5216 S To substrate +2 41.00 22.550 4.1 36.9 0.1 11,785 

5S-E17 5216 S To substrate +2 42.00 23.100 4.2 37.8 0.1 7,862 

5S-E18 5216 S To substrate +2 42.00 23.100 4.2 37.8 0.1 6,623 

5S-E19 5216 S To substrate +2 43.00 23.650 4.3 38.7 0.1 4,471 

5S-E20 5216 S To substrate +2 43.00 23.650 4.3 38.7 0.1 3,864 

5S-F3 5216 S Lifecycle 35.00 19.250 3.5 31.5 0.1 395,388 

5S-F4 5216 S Lifecycle 36.00 19.800 3.6 32.4 0.1 266,686 

5S-F5 5216 S Lifecycle 36.00 19.800 3.6 32.4 0.1 452,517 

5S-F7 5216 S Lifecycle 37.00 20.350 3.7 33.3 0.1 132,025 

5S-F8 5216 S Lifecycle 37.00 20.350 3.7 33.3 0.1 188,861 

5S-F10 5216 S Lifecycle 38.00 20.900 3.8 34.2 0.1 85,257 

5S-F11 5216 S Lifecycle 38.00 20.900 3.8 34.2 0.1 61,902 

5S-F12 5216 S Lifecycle 39.00 21.450 3.9 35.1 0.1 34,067 

5S-F13 5216 S Lifecycle 39.00 21.450 3.9 35.1 0.1 30,256 

5S-F14 5216 S Lifecycle 40.00 22.000 4.0 36.0 0.1 18,329 

5S-F15 5216 S Lifecycle 40.00 22.000 4.0 36.0 0.1 17,204 

5S-F17 5216 S Lifecycle 41.00 22.550 4.1 36.9 0.1 21,198 

5S-F18 5216 S Lifecycle 41.00 22.550 4.1 36.9 0.1 13,773 

5S-F19 5216 S Lifecycle 42.00 23.100 4.2 37.8 0.1 6,921 

5S-F20 5216 S Lifecycle 42.00 23.100 4.2 37.8 0.1 6,523 
22

Table 7. Fatigue results for 114 E glass. 

Specimen 

No. Material Group 

Max 

Stress 

(KSI) 

Mean 

Stress 

(KSI) 

Min 

Stress (KSI) 

Stress 

Amplitude 

(KSI) 

R-Value Cycles 

114-B3 114 Baseline 23.00 12.650 2.3 10.350 0.1 1,015,489 

114-B4 114 Baseline 24.00 13.200 2.4 10.800 0.1 513,758 

114-B5 114 Baseline 24.00 13.200 2.4 10.800 0.1 461,617 

114-B6 114 Baseline 25.00 13.750 2.5 11.250 0.1 202,588 

114-B7 114 Baseline 25.00 13.750 2.5 11.250 0.1 159,098 

114-B9 114 Baseline 26.00 14.300 2.6 11.700 0.1 105,775 

114-B10 114 Baseline 26.00 14.300 2.6 11.700 0.1 177,098 

114-B11 114 Baseline 27.00 14.850 2.7 12.150 0.1 77,256 

114-B12 114 Baseline 27.00 14.850 2.7 12.150 0.1 84,092 

114-B13 114 Baseline 28.00 15.400 2.8 12.600 0.1 86,174 

114-B15 114 Baseline 28.00 15.400 2.8 12.600 0.1 52,074 

114-B17 114 Baseline 29.00 15.950 2.9 13.050 0.1 30,291 

114-B18 114 Baseline 29.00 15.950 2.9 13.050 0.1 27,980 

114-B19 114 Baseline 30.00 16.500 3.0 13.500 0.1 13,462 

114-B20 114 Baseline 30.00 16.500 3.0 13.500 0.1 19,359 

114-A1 114 Hand sanded 23.00 12.650 2.3 10.350 0.1 785,065 

114-A2 114 Hand sanded 24.00 13.200 2.4 10.800 0.1 449,825 

114-A4 114 Hand sanded 24.00 13.200 2.4 10.800 0.1 339,289 

114-A5 114 Hand sanded 26.00 14.300 2.6 11.700 0.1 66,933 

114-A7 114 Hand sanded 26.00 14.300 2.6 11.700 0.1 70,609 

114-A8 114 Hand sanded 28.00 15.400 2.8 12.600 0.1 35,154 

114-A9 114 Hand sanded 28.00 15.400 2.8 12.600 0.1 37,572 

114-A10 114 Hand sanded 29.00 15.950 2.9 13.050 0.1 25,038 

114-A12 114 Hand sanded 29.00 15.950 2.9 13.050 0.1 26,303 

114-A13 114 Hand sanded 30.00 16.500 3.0 13.500 0.1 12,322 

114-A14 114 Hand sanded 30.00 16.500 3.0 13.500 0.1 17,323 

114-A16 114 Hand sanded 27.00 14.850 2.7 12.150 0.1 40,571 

114-A18 114 Hand sanded 25.00 13.750 2.5 11.250 0.1 88,825 

114-A19 114 Hand sanded 25.00 13.750 2.5 11.250 0.1 87,053 

114-A20 114 Hand sanded 27.00 14.850 2.7 12.150 0.1 48,526 

114-C2 114 To primer 23.00 12.650 2.3 10.350 0.1 992,004 

114-C3 114 To primer 24.00 13.200 2.4 10.800 0.1 516,785 

114-C4 114 To primer 24.00 13.200 2.4 10.800 0.1 730,055 

114-C5 114 To primer 25.00 13.750 2.5 11.250 0.1 155,624 

114-C6 114 To primer 25.00 13.750 2.5 11.250 0.1 230,304 

114-C7 114 To primer 26.00 14.300 2.6 11.700 0.1 95,848 

114-C8 114 To primer 26.00 14.300 2.6 11.700 0.1 150,668 

114-C9 114 To primer 27.00 14.850 2.7 12.150 0.1 79,672 

114-C13 114 To primer 27.00 14.850 2.7 12.150 0.1 71,002 

114-C15 114 To primer 28.00 15.400 2.8 12.600 0.1 62,000 

114-C16 114 To primer 28.00 15.400 2.8 12.600 0.1 76,593 

114-C17 114 To primer 29.00 15.950 2.9 13.050 0.1 30,296 

114-C18 114 To primer 29.00 15.950 2.9 13.050 0.1 28,315 

114-C19 114 To primer 30.00 16.500 3.0 13.500 0.1 11,565 

114-C20 114 To primer 30.00 16.500 3.0 13.500 0.1 14,149 

114-D1 114 To substrate 23.00 12.650 2.3 10.350 0.1 216,676 
23

Table 7. Fatigue results for 114 E glass (continued). 

Specimen 

No. Material Group 

Max 

Stress 

(KSI) 

Mean 

Stress 

(KSI) 

Min 

Stress (KSI) 

Stress 

Amplitude 

(KSI) 

R-Value Cycles 

114-D2 114 To substrate 24.00 13.200 2.4 10.800 0.1 156,362 

114-D3 114 To substrate 24.00 13.200 2.4 10.800 0.1 251,655 

114-D4 114 To substrate 25.00 13.750 2.5 11.250 0.1 121,664 

114-D5 114 To substrate 25.00 13.750 2.5 11.250 0.1 84,215 

114-D7 114 To substrate 26.00 14.300 2.6 11.700 0.1 73,431 

114-D9 114 To substrate 26.00 14.300 2.6 11.700 0.1 75,061 

114-D10 114 To substrate 27.00 14.850 2.7 12.150 0.1 47,781 

114-D12 114 To substrate 27.00 14.850 2.7 12.150 0.1 45,687 

114-D13 114 To substrate 28.00 15.400 2.8 12.600 0.1 28,302 

114-D14 114 To substrate 28.00 15.400 2.8 12.600 0.1 34,512 

114-D15 114 To substrate 29.00 15.950 2.9 13.050 0.1 5,504 

114-D18 114 To substrate 29.00 15.950 2.9 13.050 0.1 10,002 

114-D19 114 To substrate 23.00 12.650 2.3 10.350 0.1 385,125 

114-D20 114 To substrate 22.00 12.100 2.2 9.900 0.1 525,645 

114-E4 114 To substrate +2 23.00 12.650 2.3 10.350 0.1 36,666 

114-E5 114 To substrate +2 24.00 13.200 2.4 10.800 0.1 12,719 

114-E6 114 To substrate +2 24.00 13.200 2.4 10.800 0.1 13,410 

114-E7 114 To substrate +2 19.00 10.450 1.9 8.550 0.1 488,903 

114-E9 114 To substrate +2 19.00 10.450 1.9 8.550 0.1 298,786 

114-E10 114 To substrate +2 20.00 11.000 2.0 9.000 0.1 142,864 

114-E11 114 To substrate +2 20.00 11.000 2.0 9.000 0.1 256,874 

114-E13 114 To substrate +2 27.00 14.850 2.7 12.150 0.1 7,079 

114-E14 114 To substrate +2 27.00 14.850 2.7 12.150 0.1 4,294 

114-E15 114 To substrate +2 18.00 9.900 1.8 8.100 0.1 750,899 

114-E16 114 To substrate +2 18.00 9.900 1.8 8.100 0.1 1,205,876 

114-E17 114 To substrate +2 21.00 11.550 2.1 9.450 0.1 125,378 

114-E18 114 To substrate +2 21.00 11.550 2.1 9.450 0.1 194,528 

114-E19 114 To substrate +2 22.00 12.100 2.2 9.900 0.1 66,619 

114-E20 114 To substrate +2 30.00 16.500 3.0 13.500 0.1 3,463 

114-F1 114 Lifecycle 18.00 9.900 1.8 8.100 0.1 1,016,958 

114-F2 114 Lifecycle 19.00 10.450 1.9 8.550 0.1 265,481 

114-F3 114 Lifecycle 19.00 10.450 1.9 8.550 0.1 378,456 

114-F4 114 Lifecycle 20.00 11.000 2.0 9.000 0.1 245,826 

114-F5 114 Lifecycle 20.00 11.000 2.0 9.000 0.1 126,426 

114-F6 114 Lifecycle 21.00 11.550 2.1 9.450 0.1 106,231 

114-F7 114 Lifecycle 21.00 11.550 2.1 9.450 0.1 156,987 

114-F10 114 Lifecycle 22.00 12.100 2.2 9.900 0.1 48,591 

114-F11 114 Lifecycle 23.00 12.650 2.3 10.350 0.1 51,211 

114-F12 114 Lifecycle 24.00 13.200 2.4 10.800 0.1 17,845 

114-F13 114 Lifecycle 27.00 14.850 2.7 12.150 0.1 8,915 

114-F14 114 Lifecycle 30.00 16.500 3.0 13.500 0.1 4,853 
24

5. Discussion 

5.1 Short-Beam Shear 

It can be observed in the data that the hand-sanding process is somewhat detrimental to the shortbeam shear strength of the composites tested in this work. It appears that, although this is an 

approved process, there are surface effects of the sanding that leave residual conditions which 

tend to decrease overall shear strength. Although this decrease is not overwhelming, ~10% for 

the composites tested, it is statistically significant. The ramifications of imparting this strength 

decrease on the materials have obviously not been significant enough to cause catastrophic 

service failure of the rotor blades during flight. The long-term effects of this decrease are 

unknown. The FlashJet process appears to only slightly affect the short-beam shear strength of 

these composites materials. The decrease from the baseline was less than that of the handsanding process. It does appear that, in general, the more aggressive the FlashJet processing, the 

more substantial the decrease in strength becomes. This is demonstrated by comparing the 

groups that completely remove the paint to the group that does not, the “stripped-to-primer” 

group. In all cases, the “stripped-to-primer” group was the best performer among the FlashJet 

groups. Indeed, it appears that utilizing FlashJet to strip the topcoat does not significantly reduce 

the short-beam shear strength of these composite materials at all. All FlashJet groups 

outperformed the current hand-sanding process in short-beam shear testing. 

5.2 Tensile Testing 

The data suggests that the hand-sanding process currently being utilized at CCAD is somewhat 

detrimental to the overall tensile strength of the composite materials. The reduction in tensile 

strength varied from 15%–25% across the groups but was statistically significant. Only five 

samples were tested from each group and there was a high degree of scatter in the data, so 

tremendous weight should not be given to this apparent trend. The FlashJet groups performed 

better than the hand-sanded group under tensile testing. Their tensile strength results were equal 

to or only slightly lower than the baseline group. It did not appear that the FlashJet process 

significantly reduced the tensile strength of the composite materials tested. 

5.3 Fatigue Testing 

In contrast to the short beam shear and tensile testing, there appeared to be significant 

detrimental effects of the FlashJet process on the fatigue strength of the composite materials 

tested when removal to the substrate was performed. The trends were uniform and consistent 

across the materials. The “stripped-to-substrate plus two” and “lifecycle” groups performed 

significantly below the others. It would appear that the more intense and aggressive the FlashJet 

process is, the more significant the fatigue-life reduction. Although these groups were included 

only to assess what could happen if something went wrong over the lifetime of the component, it 
25

revealed that the FlashJet process certainly had the inherent ability to cause damage. CCAD had 

significant difficulties optimizing the FlashJet parameters for removal of both the topcoat and 

especially the primer. It can be observed in the photos that the removal of the coating system 

was not uniform. This may be caused by several factors including those dependent on the 

system itself, e.g., the xenon bulb, voltage consistency, etc. Regardless, if it is necessary to 

completely remove the primer for the maintenance and overhaul processing, then significant 

improvements on uniformity and consistency will have to happen before FlashJet is a viable 

option. In contrast, using FlashJet to remove just the topcoat appears to leave the substrate 

unaffected. The “stripped-to-primer” group performed on par with the baseline group. This 

would suggest that the detrimental effects of the FlashJet on these composite materials were, 

although significant, very superficial as the primer is only 0.001–0.0015 in thick. Optimization 

of the FlashJet parameters would improve the performance. It is unknown, however, whether the 

FlashJet process will prove nimble or repeatable enough to remove just the primer consistently 

without damaging the substrates. That certainly was not the case within this study. It may be 

that experience and understanding of the system will improve the overall long-term performance. 

6. Conclusions 

The hand-sanding process appears to impart a slight detrimental reduction in both short-beam 

shear and tensile strength of the materials tested. The long-term effects of this reduction are 

unknown, but do not appear to be largely significant since there have been no service failures. 

The fatigue performance is ever so slightly reduced by the hand-sanding process.

The effects of the FlashJet process are almost insignificant on the short-beam shear and tensile 

strength of the materials. However, in fatigue, the detrimental effects become readily apparent. 

Stripping to the substrate over the life of the component or performing just two additional passes 

over a paint-free area significantly reduces the fatigue strength of these materials. If the FlashJet 

is utilized to just remove the topcoat and no contact with the substrate is made, then the 

detrimental effects disappear. Therefore, either considerable optimization of the system must 

take place, or the utilization of the system must be confined to just removal of the topcoat. In 

either case, repeatability of the system will have to be addressed as, in its present condition, it 

does not appear nimble enough to remove the primer evenly without imparting damage.
26

7. References 

1. BMS8-196. Epoxy, Resin Pre-Impregnated Non-Woven E-Glass Fiber Materials 1994. 

2. HMS16-1113. Laminate, Fiberglass, Unidirectional, Epoxy 1998. 

3. SS9610-001. Glass Filament 1997. 

4. MIL-P-23377. Primer Coatings: Epoxy, High-Solids 2003. 

5. MIL-P-46168. Coating Aliphatic Polyurethane, Chemical Agent Resistant 2004. 

6. ASTM-D-3039. Standard Test Method for Tensile Properties of Fiber-Resin Composites. 

Annu. Book ASTM Stand. 2002. 

7. ASTM-D-3479. Standard Test Method for Tension-Tension Fatigue of Oriented Fiber, 

Resin Matrix Composites. Annu. Book ASTM Stand. 2004. 

8. ASTM-D-2344. Short Beam Shear Strength of Polymer Matrix Composite Materials and 

Their Laminates. Annu. Book ASTM Stand. 2003. 
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