Conventional Aerial Delivery Systems
Ann Suter, Wildland Fire Chemical Systems - MTDC
Conventional tanks divide the retardant load into several compartments. The compartments can be released individually or
multiple compartments can be released simultaneously to increase both the volume and the flow rate and hence the coverage
level. Multiple compartments can also be released sequentially at the appropriate release interval to increase the volume while
maintaining the coverage level of a single compartment release. Conventional tanks often use deployable flow restrictors to help
control the flow rate. Restrictors are physical barriers that lower the flow rate as liquid is released from the tank. There are a
variety of conventional tanks with different shapes, compartments and capacities. Having the option of restricting the flow
doubles the number of flow rates available to the system
Conventional Tank
Each Compartment holds 250 gallons.
2200
2000
gallons per second
1800
1600
1400
1200
1000
800
2 compartments with restrictors = 430 gallons/second
600
400
200
1 comparment with restrictors = 215 gallons/second
0
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Seconds
The figure to the left above shows two compartments released simultaneously with restrictors down. Each compartment flows at
about an average of 215 gallons per second. The dotted line shows the flow rate for one compartment while the solid line shows
the flow rate for two.
Conventional Tank
Each Compartment holds 250 gallons.
2200
2 compartments unrestricted = 1370 gallons/second
2000
gallons per second
1800
1600
1400
1200
1 comparment unrestricted = 685 gallons/second
1000
800
600
400
200
0
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Seconds
The figures above illustrate the same thing but without the restrictors deployed. Each compartment flows about an average of
685 gallons per second.
Revision Date 4/17/03
asuter@fs.fed.us 406-329-4815
Conventional Systems
Aircraft
NO.
Owner/Operator
05
06
07
09
10
11
12
33
48
55
60
62
65
66
68
72
73
74
75
76
77
78
80
81
86
87
88
89
90
91
92
94
95
97
99
102
105
109
111
117
119
139
140
151
152
154
160
161
162
215
263
266
715
716
794
Neptune, Inc.
Neptune, Inc.
Neptune, Inc.
Neptune, Inc.
Neptune, Inc.
Neptune, Inc.
Neptune, Inc.
Int'l Air Response
Minden Air Corp
Minden Air Corp
TBM, Inc.
TBM, Inc.
TBM, Inc.
TBM, Inc.
TBM, Inc.
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
CDF
Hawkins & Powers
Minden Air Corp
Central Air Service
Central Air Service
Central Air Service
Central Air Service
Central Air Service
ARDCO
Hawkins & Powers
Hawkins & Powers
ARDCO
ARDCO
Marsh Aviation
Aero Flite
Aero Flite
Aero Flite
North Carolina State FS
Minnesota State
Minnesota State
Helicopter Transport Ser
Helicopter Transport Ser
Heavilift Inc. Helicopters
Type
P2V-5
P2V-5
P2V-5
P2V-7
P2V-7
P2V-7
P2V-7
DC-7B
P2V-7
P2V-7
DC-7B
DC-7
C-54E
DC-7
DC-6
S2A
S2A
S2A
S2A
S2A
S2A
S2A
S2A
S2A
S2A
S2A
S2T
S2T
S2T
S2T
S2A
S2A
S2A
KC-97
P2V-7
C-54E
C-54D
C-54D
C-54E
DC-4
C-54G
P2V-7
P2V-7
C-54E
C-54D
S2-A
C-54E
C-54G
DC-4
CL-215
CL-215
CL-215
S-64
S-64
S-64
Aircraft
"N" No.
96278
9855f
1386k
4235T
Serial No.
14447
96264
4887C
131459
131445
131424
150282
144681
8010
128346
45351
355MA
838D
401US
8502R
6353C
90739
443DF
406DF
411DF
420DF
417DF
423DF
412DF
404DF
447DF
453DF
450DF
426DF
425DF
427DF
432DF
442DF
446DF
448DF
1365n
299MA
816D
96454
6816D
96541
31356
406WA
139HP
140HP
460WA
9015Q
736MA
96358
82FA
3054V
148344
45347
45145
44-9141
45486
43044
195
293
476
388
61
246
222
455
417
572
421
0341-028
0341-029
0382-011
787-41
255
175
684
52-2698
147961
44-9150
42-72759
44-9142
56489
42914
35944
145906
140443
44-9133
43-17228
136736
44-9058
35960
10547
263NR
266NR
N470KG
N484KG
44094
1082
1102
Max
Doors
6-doors
6-doors
6-doors
6-doors
6-doors
6-doors
6-doors
8-doors
6-doors
6-doors
8-doors
8-doors
8-doors
8-doors
8-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
4-doors
16-doors
6-doors
4-doors
4-doors
4-doors
4-doors
4-doors
8-doors
6-doors
6-doors
8-doors
8-doors
4-doors
8-doors
8-doors
8-doors
2-doors
2-doors
2-doors
4-doors
4-doors
4-doors
Vol.
2,450
2,450
2,450
2,450
2,450
2,450
2,450
3,000
2,450
2,450
3,000
3,000
2,000
3,000
2,450
800
800
800
800
800
800
800
800
800
800
800
1,200
1,200
1,200
1,200
800
800
800
4,000
2,450
2,000
2,000
2,000
2,000
2,000
2,200
2,450
2,450
2,000
2,000
800
2,000
2,000
2,000
1,400
1,400
1,400
2,000
2,000
2,000