User Guide

Spares planning Page 193 of 544
Option 11C and 11C Mini Technical Reference Guide
NFT values
Table 59 translates NFT values to the number of spares required in stock:
N—Number in use
F—Failure rate
T—Turnaround time (in hours)
Table 59
Number of spares required (Part 1 of 2)
NFT values
Number
of spares
0 0.0010 1
0.0010 0.0452 2
0.0452 0.1890 3
0.189 0.425 4
0.425 0.734 5
0.734 1.090 6
1.09 1.50 7
1.50 1.95 8
1.95 2.43 9
2.43 2.94 10
2.94 3.46 11
3.46 4.01 12
4.01 4.58 13
4.58 5.16 14
5.16 5.76 15
5.76 6.37 16