Appendix 3 -1/3RD AND LARGER BLADED MASS (SEE FIGURE 2) ‡ 3° + 5°.
1/30 BLADED MASS (INTERMEDIATE) (SEE FIGURE 3) * 15°.
SMALL FRAGMENTS (SEE PARAGRAPH 5B(4))
FRAGMENT SPREAD ANGLE IS THE ANGLE
MEASURED FORE AND AFT, FROM THE
CENTER OF THE PLANE OF ROTATION
INITIATING AT THE ENGINE OR APU SHAFT
CENTERLINE NOTE: 1) THE POSSIBILITY OF TURBINE MOVEMENT SHOULD BE CONSIDERED.
2) ALL ROTORS ARE CONSIDERED TO BE FULLY BLADED FOR CALCULATING MASS.
3) FAILURE OF EACH ROTOR STAGE SHOULD BE CONSIDERED.
FIGURE АPХ3-1. ESTIMATED PATH OF FRAGMENTS Page A3-10
Appendix 3
MAXIMUM DIMENSION CG 1/3 b 120° Where R = disc radius b = blade length The CG is taken to lie on the maximum dimension as shown.
FIGURE APX3-2. SINGLE ONE-THIRD DISC FRAGMENT Page A3- 11
Appendix 3 1/3 (R + b) Where R = disc radius b = blade length Maximum dimension = 1/3 (R + b) Mass assumed to be 1/ 30 th of bladed disc CG is taken to lie on the disc rim FIGURE АPХ3-3. INTERMEDIATE AND SMALL PIECES OF DEBRIS Page А3-12
7/30/97
GEOMETRIC CG 1/3 X WHERE X = AIRFOIL LENGTH (LESS BLADE ROOT & PLATFORM) FIGURE АPХ3-4 CG IS TAKEN TO LIE AT THE CENTERLINE OF THE 1/3 FRAGMENT
FRAGMENT VELOCITY TAKEN AT
GEOMETRIC CG
FRAGMENT MASS ASSUMED TO BE 1/3 OF THE AIRFOIL MASS Page A3- 13 BLADE FRAGMENT DEFINITION Appendix 3 AC 29-2B
Appendix 3
FRAGMENT
ROTATIONAL KE = ½1∞2
TRANSLATIONAL KE = ½ mv 100 TOTAL
KINETIC ENERGY (PERCENT) 60 120 180 240 300 360
ROTATIONAL TRANSLATIONAL
FRAGMENT SIZE C FIGURE APХ3-5. DISTRIBUTION OF TRANSLATIONAL AND ROTATIONAL
KINETIC ENERGY OF ROTOR-COMPONENT FRAGMENTS AS A FUNCTION
OF FRAGMENT SIZE Page A3-14
Appendix 3 CG of Fragment Becomes Center of Rotation of Fragment For Separation Distance Calculations:
1/3 Rotor with 1/3 Blade Height FIGURE APX3-6. CROSS SECTION THROUGH AIRCRAFT AT PLANE
OF ROTATION OF THE ENGINE DISK FRAGMENT Page A3- 15