CIRRUS DESIGN CAPS, Руководство по компонентам

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12128-001 95-01
Page 4 15 Sept 2002
A. Activation System (See Figure 95-012)
The rocket motor is activated by pulling an activation handle mounted in a recessed enclosure located
in the headliner above the pilot/copilot. This handle is connected to the rocket motor igniter with a flex-
ible, stainless steel aircraft grade cable routed through a cable housing above the cabin ceiling head-
liner.
A cover/placard is attached to the perimeter of the activation handle enclosure to prevent the handle
from being pulled accidentally. The placard identifies the system, presents the actions required to
deploy it, defines its operating envelope, provides appropriate warnings, and references the airplane
Flight Manual.
A maintenance safety pin is provided to ensure that the activation handle is not pulled during mainte-
nance or other ground operation. The pin is inserted through the handle retainer and barrel locking the
handle in the “safe” position. A “Remove Before Flight” streamer is attached to the pin. The handle is
the only part of the system accessible to the pilot in flight.
B. Solid Propellant Rocket Motor Assembly (See Figure 95-012)
The CAPS rocker motor assembly consists of the igniter, rocket motor, and rocket motor base. The
igniter consists of a steel spring, a plunger, two firing trains, and a firing pin actuator to which the acti-
vation cable is attached. Each firing train consists of a firing pin and primer which ignites a booster. In
its normal position the firing pin actuator and plunger are interlocked with two ball bearings held in
place by the inner wall of the igniter body.
(1) Rocket Igniter
Pulling the activation cable compresses the rocket igniter spring and cocks the plunger. One
half-inch of plunger travel is required to release the ball bearings and allow the plunger to strike
the firing pins. The firing pins then strike the shotgun-type primers which ignite a black powder
and magnesium primary booster in the end of the igniter. The igniter is unarmed in its normal
configuration since the spring is un-compressed and the plunger is separated from the firing pins
by a 0.060-inch gap.
The igniter primary booster ignites a secondary black powder and magnesium booster contained
in the rocket motor base. The extra booster material is used to ensure ignition of the larger rocket
motor. The rocket motor base has a conical protrusion which sprays hot particles past the rocket
nozzle and across the surface of the rocket motor's solid propellant. Once ignited, the grains will
burn on all exposed surfaces to form hot gases which are exhausted through the nozzle provid-
ing thrust.
(2) Rocket Motor
The CAPS rocket motor uses stored chemical energy in the form of a solid propellant to provide
the thrust forces necessary to rapidly remove the enclosure cover and extract the parachute
from its enclosure.
The rocket motor components consist of the motor case, motor aft bulkhead, propellant, and
nozzle. The motor case/aft bulkhead contains the propellant and serves as a pressure chamber
when the propellant is burning.
The rocket motor uses a composite propellant, consisting of a heterogeneous mixture of ammo-
nium perchlorate (AP) and aluminum powder (Al), the oxidizer and fuel. These are the most
commonly used types of these ingredients in modern solid propellants.
The rocket motor nozzle provides for the expansion and supersonic acceleration of the hot
gases. The rocket motor has been designed to specifically meet the extraction requirements of
the CAPS parachute.