95-01-01
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EFFECTIVITY:
C I R R U S
C O M P O N E N T M A I N T E N A N C E M A N U A L - C A P S
M O D E L S R 2 0
4 May 2015
2. DESCRIPTION AND OPERATION
The Cirrus Airplane Parachute System consists of a parachute, a solid-propellant rocket to deploy the
parachute, a rocket activation system, and a harness faired into the fuselage structure.
A composite enclosure containing the parachute and solid-propellant rocket is mounted to the airplane
structure immediately aft of the baggage compartment bulkhead. The enclosure is covered and protected
from the elements by a thin composite cover.
The parachute is enclosed within a deployment bag that stages the deployment and inflation sequence.
The deployment bag creates an orderly deployment process by allowing the canopy to inflate only after the
rocket motor has pulled the parachute lines taut.
The parachute itself is a 2400 sq ft round canopy equipped with a slider, an annular-shaped fabric panel
with a diameter significantly less than the open diameter of the canopy. The canopy suspension lines are
routed through grommets so that the slider is free to move along the suspension lines. Since the slider is
positioned at the top of the suspension lines near the canopy, at the beginning of the deployment
sequence, the slider limits the initial diameter of the parachute and the rate at which the parachute inflates.
The canopy inflates as the slider moves down the suspension lines.
A three-point attachment harness connects the airplane to the parachute. The harness consists of two for-
ward straps faired into the fuselage skin and attached to the firewall, and one rear strap attached to FS 222
bulkhead located directly forward of the parachute compartment. The harness system is designed to con-
trol the pitch dynamics of the airplane during the deployment cycle by limiting the aft attachment strap’s
length until the cycle is complete. This is accomplished by utilizing a variable length strap section. The
shorter section, which initially supports the load, employs a mechanical release that is activated by two
pyrotechnic cutters which fire when the short section is pulled taut during extraction. The harness strap
then lengthens and load is transferred to the longer section.
Two separate and deliberate pilot actions are required to deploy the parachute. The first action requires the
pilot to remove the access cover from the activation handle enclosure. The second action requires the pilot
to pull the activation handle out, and down several inches.
Upon pulling the activation handle, the activation cable compresses the igniter’s steel spring, cocks the
plunger and the following sequence is initiated:
Serials 1005 thru 1267 before SB2X-95-20,
Serials 1268 thru 1422 before SB2X-95-17,
Serials 1423 & subs w/o Perspective before SB2X-95-18, 2016 thru 2227:
When one half-inch of plunger
travel is reached, captured ball bearings are released allowing the plunger to strike the firing pins. The fir-
ing pins strike two primers which ignite the primary booster.
Serials 1005 thru 1267 after SB2X-95-20,
Serials 1268 thru 1422 after SB2X-95-17,
Serials 1423 & subs w/o Perspective after SB2X-95-18, 2228 & subs:
When one half-inch of plunger travel
is reached, captured ball bearings are released allowing the plunger to close the electrical contacts. The
closed electrical circuit ignites the primary booster.
The primary booster ignites a secondary booster ensuring ignition of the larger rocket motor. Once ignited,
the rocket propellant’s hot gases are exhausted through the rocket nozzle. The rocket impacts and dis-
bonds the parachute compartment cover pulling the deployment bag from the enclosure. The deployment
bag then stages the suspension line deployment and inflation of the parachute.
As the parachute inflates, the forward harness assembly grows taut, pulls free of the fuselage skin, and
stops at the forward attach fitting which supports the forward portion of the airplane.
The aft harness is pulled taut, the line cutters are activated, and approximately eight seconds later “fire”
and sever the nylon cord. The three-link release mechanism then opens allowing the aft harness to fully
extend. The airplane then assumes its touchdown attitude; approximately ten degrees nose down, to opti-
mize occupant protection.
