MD Helicopters MD Explorer - Maintenance Practices; Fire Extinguisher System Inspection

CSP−900RMM−2MD Helicopters, Inc.
Rotorcraft Maintenance Manual
Page 201
Revision 4
26-20-20
FIRE EXTINGUISHER SYSTEM
MAINTENANCE PRACTICES
1. Fire Extinguisher System Inspection
(1). Remove engine cowl assemblies L260
and R260 (Ref. Section 06-00-00).
(2). Inspect left and right distribution tubes
for obstruction, restrictions, dents, and
scratches. Maximum allowed dent
depth 0.015 in (0.381 mm) or scratch
depth 0.0035 in (0.0889 mm).
(3). Open baggage compartment door L262
(Ref. Section 06-00-00).
(4). Inspect fire bottle primary and alter
nate discharge port for cracks, corro
sion, chafing, or scoring. Use bright
light and 10 power magnifier. No
discrepancies allowed.
(5). Inspect discharge cartridge connector
for condition and security. Repair or
replace as required.
(6). Inspect fire bottle mounting brackets
for condition and security.
(7). Inspect fire bottle assembly for security,
dents, scratches and unserviceable
condition. Replace as required.
 Maximum allowed, dent depth 0.063
in per 1.0 in (0.063 mm per mm)
average dent diameter or scratch
depth 0.005 in (0.125 mm).
(8). Inspect discharge tube assemblies for
dents, scratches and unserviceable
condition. Maximum allowed dent
depth depth 0.015 in (0.381 mm) or
scratch depth 0.0035 in (0.0889 mm).
(9). Inspect crossflow tube assemblies for
dents, scratches and unserviceable
condition. Maximum allowed dent
depth depth 0.015 in (0.381 mm) or
scratch depth 0.0035 in (0.0889 mm).
(10). Inspect fire bottle pressure gauge for
condition, dented or broken gauge,
broken glass, and legible range mark
ing. Replace fire bottle as required.
(11). Fire bottle above minimum serviceable
pressure (Ref. Table 201).
Table 201. Minimum Serviceable Fire Bottle
Pressure
Temperature Gauge Reading
C F PSIG
−40.0 −40° 395
−34.4 −30° 420
−28.9 −20° 450
−23.3 −10° 465
−17.8 0° 485
−12.2 +10° 500
−6.7 +20° 520
−1.1 +30° 555
+4.4 +40° 585
+10.0 +50° 625
+15.6 +60° 660
+21.1 +70° 700
+26.7 +80° 745
+32.2 +90° 780
+37.8 +100° 820
+43.3 +110° 885
+48.9 +120° 950
(12). Close baggage compartment door L262
(Ref. Section 06-00-00).
(13). Install engine cowl assemblies L260
and R260 (Ref. Section 06-00-00).