Beechcraft C-12C Operator And Technical Reference Manual page 99

Table 2-6. Oxygen Duration in Minutes for 49 Cubic Foot System (Continued)
When operating with a 100% cylinder capacity, read the duration in minutes directly from the
table. However, if operating with less than a 100% cylinder capacity pressure (reference
Figure 2-25), perform the following computation: Total crew (2) LPM usage at cabin pressure
altitude; Total passenger LPM usage at cabin pressure altitude; Total LPM usage of both crew
and passengers. Multiply 1222 liters times the percent of rated capacity at NTPD and divided
by total crew and passenger LPM usage to obtain total (oxygen remaining) duration in
minutes.
TWO MAN CREW
TWO MAN CREW
PLUS ONE PASS
TWO MAN CREW
PLUS TWO PASS
TWO MAN CREW
PLUS THREE PASS
CABIN CREW MASK
PRESSURE CONDITION
ALTITUDE
NOTE
31,000
20,000
20,000 NORMAL
15,000
15,000 NORMAL
10,000
10,000 NORMAL
31,000
20,000
20,000 NORMAL
15,000
15,000 NORMAL
10,000
10,000 NORMAL
31,000
20,000
20,000 NORMAL
15,000
15,000 NORMAL
10,000
10,000 NORMAL
31,000
20,000
20,000 NORMAL
15,000
15,000 NORMAL
10,000
10,000 NORMAL
TOTAL FLOW
LPM-NTPD
100% 8.4
100% 15.2
7.2
100% 19.0
10.2
100% 23.8
13.8
100% 12.1
100% 18.9
10.9
100% 22.7
13.9
100% 27.5
17.5
100% 15.8
100% 22.6
14.6
100% 26.4
17.6
100% 31.2
21.2
100% 19.5
100% 26.3
18.3
100% 30.1
21.3
100% 34.9
24.9
TM 1-1510-218-10
DURATION IN
MINUTES (1)
145.5
80.4
169.7
64.3
119.8
51.3
88.6
101.0
64.7
112.1
53.8
87.9
44.4
69.8
77.3
54.1
83.7
46.3
69.4
39.2
57.6
62.7
46.5
66.8
40.6
57.4
35.0
49.1
2-83