this, you first evacuate air from a test chamber
to simulate an increase in altitude. When you have
achieved a simulated altitude above the preset
altitude of the ripcord release, you extract the
arming pin, which arms the parachute ripcord
release firing mechanism. Then you bleed outside
air back into the test chamber at a controlled rate
to simulate a specific rate of descent. When the
pressure reaches the value for which the automatic
ripcord release has been set, the aneroid will
unlock the sear if the pressure sensitivity is within
tolerance.
The test chamber, its evacuation system,
instrumentation, and controls are packaged
in one container. The test chamber is de-
signed to withstand a vacuum equivalent
to an altitude of 30,000 feet. The chamber
holds the entire 7000 series automatic para-
chute ripcord release, and it includes the
necessary brackets to support and position
the ripcord release within the chamber dur-
ing the test cycle. An access door/observation
window is also provided.
NOTE: Before testing an automatic
parachute ripcord release, the test chamber
altimeter should read 29.92 inches of
mercury barometric pressure.
RIPCORD RELEASE TEST
PROCEDURE
Plug the test unit’s power cord into a
115-volt, 60 Hz, ac power source. Place
the power switch in the ON position, open
the test chamber door, and insert the arm-
ing pin cable into the side of the ripcord
release with the aneroid end toward the
operator.
To test the ripcord release, follow these
procedures:
1. Ensure the test chamber has been cali-
brated. Install the test chamber substitute arming
pin into the ripcord release. If the barometric
pressure reading of the altimeter isn’t 29.92, you
will not get a true reading of the firing altitudes.
Therefore, you must adjust the altimeter to the
proper setting when required.
2. Install a dummy cartridge.
Figure 2-10.—Locking barrel assembly.
CAUTION
DO NOT RELEASE THE RIPCORD
RELEASE FIRING MECHANISM
WITHOUT A DUMMY CARTRIDGE
INSTALLED, AS THIS COULD DIS-
TORT THE FIREWALL. THIS DIS-
TORTION COULD CAUSE A LATER
MALFUNCTION.
3. Press the barrel down into position in the
receiver. As the barrel reaches the proper position,
exert forward pressure on the snap. lock, causing
the snap lock pins to lock the barrel in position
(fig. 2-10).
4. Install the barrel and receiver into the test
chamber. Check your altimeter (fig. 2-9) for a
setting of 29.92.
5. Evacuate the chamber to an altitude of
25,000 feet. This is done by using the climb toggle
switch.
6. Decrease the altitude by using the descend
toggle. The chamber simulates descent at a rate
of 175 to 200 feet per second.
7. At approximately 20,000 feet actuate the
arm toggle switch to withdraw the arming pin
from the barrel and receiver.
8. At the firing altitude the ripcord release
should fire. (You have a tolerance of plus or
minus 1,000 feet at this time.)
9. Record the altitude at which the ripcord
release assembly’s firing pin strikes the dummy
cartridge. The firing altitude is recorded on the
parachute configuration, inspection, and history
record. The quality assurance inspector will check
this point of the procedure.
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