STRINGER, INSPECTION DIRECTION 2, GENERAL VISUAL
Since the inspection is conducted every D-check, enter D under CHECK LEVEL.
Since 50 percent of the airplanes are inspected, enter 50 under % PHASE Ro.
D-check corresponds to 10,000 flight cycles, enter 10,000 under FREQUENCY.
Compute and enter N = 100 F/Ro = 20,000 flight cycles.
Enter ΔDTR vs. N chart at N = 20,000 flight cycles.
Read ΔDTR from DIRECTION 2 GENERAL VISUAL line.
Enter ΔDTR = 3.4 under ΔDTR.
Add the ΔDTR values 4.1 + 3.4 = 7.5 and enter at TOTAL DTR.
This value exceeds the REQUIRED DTR of 6, therefore the existing maintenance program is
adequate. No further action is necessary.
Original D6-82669 7.0 DOCUMENT USAGE
Optionally, in the second EX-1 form the percentage of eligible aircraft used for the internal inspection may be reduced by the procedure shown in Section 7.4.2.6 until the TOTAL DTR = REQUIRED DTR, providing general instruction 5.1.5 is met. A D-check general visual, with a 33 percent of eligible aircraft (Ro = 33), gives N = 100 (10,000/33) = 30,000 flight cycles. The corresponding ΔDTR = 1.9, which, when added to the C-check ΔDTR of 4.1, gives a total DTR of 6.
The completed DTR Check Form is shown on Page 7.0.14.
7.0 DOCUMENT USAGE D6-82669 Original
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Original D6-82669 7.0 DOCUMENT USAGE
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7.0 DOCUMENT USAGE D6-82669 Original
7.4.2 EXAMPLE 2
SSI - WING LOWER SURFACE REAR SPAR CHORD AND SKIN (SSI HIDDEN INTERNALLY) EXISTING MAINTENANCE ON 36 AIRPLANES (10 ELIGIBLE AIRPLANES):
.
GENERAL VISUAL AT C-CHECKS EVERY 2,500 FLIGHT CYCLES.
.
DETAILED AT D-CHECKS EVERY 10,000 FLIGHT CYCLES.
REQUIRED DTR = 4.
7.4.2.1 Existing Maintenance The completed DTR Check Form is shown on Page 7.0.18. The values are derived as follows:
SKIN, INSPECTION DIRECTION 1
Enter the appropriate data under CHECK LEVEL, % PHASE Ro, FREQUENCY, and N =100 F/Ro.
Enter the ΔDTR vs. N chart with the N values.
Read the ΔDTR values from the lines with the appropriate INSPECTION DIRECTION and METHOD:
1-GVI ΔDTR = 0.5
1-DET ΔDTR = 0.2
Enter these values under ΔDTR.
SPAR CHORD, INSPECTION DIRECTION 2
Enter the appropriate data under CHECK LEVEL, % PHASE Ro, FREQUENCY, and N =100 F/Ro.
Read the ΔDTR values from the lines with the appropriate INSPECTION DIRECTION and METHOD:
2-GVI ΔDTR = 0.4
2-DET ΔDTR = 0.3
Enter these values under ΔDTR.
Add the ΔDTR values (0.5 + 0.2 + 0.4 + 0.3 = 1.4) and enter 1.4 for TOTAL DTR.
The TOTAL DTR is less than the REQUIRED DTR. Therefore, the existing maintenance program must
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本文链接地址：737-300/400/500 补充结构检查文件 SUPPLEMENTAL STRUCTURAL INSPECTION DOCUMENT 1(20)
