 |
|||
|
|
|||
| ||||||||||
|
| MIL-T-5578C
3.5 Design. The self-sealing fuel cells shall
proved manufacturing tolerances as described
be suitable for use with fuels conforming to
in the manufacturer's specifications.
MIL-G-5572 or MIL-J-5624, or both, as
3.6.2 Fabric ply. Fuel cells shall be so fab-
specified by the procuring activity, and shall
ricated that the seam on any fabric ply shall not
be designed in conjunction with the containing
be superimposed with parallel seams of any ad-
structure to avoid concentration of loads on
jacent fabric ply.
splices, seams, fittings, or location of concen-
3.6.3 Sealant. The fuel cells shall use an
trated flexure. The assembly consisting of the
approved sealant so vulcanized as to meet the
retirement of this specification. The sealant
cell (s) and aircraft structure in which it is
mounted shall comprise the necessary strength
shall be free of foreign matter, and the thickness
to provide adequately for the stresses caused
shall agree with the approved construction
within the established manufacturing tolerance
by the following:
as described in the manufacturer's specifications.
(a) Flexing resulting from vibration
3.6.4 Fittings. All fittings used in self-
(b) Impact loads incident to takeoff, taxi-
sealing fuel cells shall conform to MIL-F-5577.
ing, and landing (including cata-
Both the inside and outside flanges of the fitting
pulting and arresting)
shall be vulcanized to the cell carcass. Every
(c) Hydraulic surge of fuel incident to all
effort shall be made to utilize fittings in a single
dynamic conditions of flight
plane. Where the aircraft design is such as to
(d) Hydraulic surge of fuel incident to
necessitate the use of double plane fittings, par-
gunfire
ticular care should be taken to provide adequate
(e) Pressure loads resulting from hydro-
exterior flange area to insure satisfactory ad-
static head of fuel during level flight
hesive strength under all conditions of opera-
or maneuvers, and resulting from
tion. The use of through bolts shall be avoided.
neutral gases, if any, used to pressur-
3.6.4.1 Screw threads. Screw threads shall
ize fuel cells.
be in accordance with MIL-S-7742. The use of
3.5.1 Dimensions. The dimensions and di-
pipe threads is prohibited.
mensional tolerances shall be developed by the
3.7 Performance. The cells and tanks, or
contractor or Government procuring activity.
specified parts thereof, shall satisfy the per-
The dimensional tolerance specified shall be such
formance requirements specified herein when
that the capacity of the production tanks will be
subjected to the following tests, as specified in
within 1.5 percent of the designed total capacity.
section 4:
3.5.2 Capacity. The head-versus-volume
curve on production tanks shall conform within
(a) Inspection ------------------------ (4.6.1)
1.5 percent to the average head-versus-volume
(b) Stand --------------------------- (4.6.2)
(c) Dissection ----------------------- (4.6.8)
curve prepared in accordance with 4.4.2.1.
(d) Inner-layer ply--------------------- (4.6.4)
3.6 Construction. The following require-
--------------- (4.6.5)
(e) C e l l s
ments apply to fuel cell construction intended
Installation -------- --------- (4.6.6)
(f)
for protection levels (A) and (B) and for the
(g) Capacity ----------------- (4.6.7)
(h) Pressure ------------------- (4.6.8)
self-sealing portions of fuel cell construction
(i) Slosh or slosh and vibration
intended for protection levels (C) and (D).
(4.6.9)
resistance
-----------
The non-self-sealing portions of construction
(j) Aging and low temperature 1eakage (4.6.10)
shall conform to MIL-T-6396, type II, class B.
(k) Accelerated load resistance
-----(4.6.11)
(l) Gunfire resistance on tank
3.6.1 Inner-layer ply. The construction
installation
--------- (4.6.12)
shall be such that it will be impossible to trans-
3.7.1 Operating temperature. The self-seal-
mit fuel to the sealant. If necessary to meet
ing fuel cell shall be- suitable for operation
this requirement, a special barrier shall be uti-
throughout the temperature range of -40 to
lized. The inner-layer ply shall be free of
foreign matter, and the thickness shall agree
160 F insofar as self-sealing performance is
with the approved construction within the ap-
concerned. For all other operating conditions,
3
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals