SADN DESCRIPTION
Some light aircraft are fitted with rocket-assisted recovery
parachute systems. These parachute systems are designed to recover
the aircraft and passengers to the ground should a serious
in-flight emergency arise.
Composite structured aircraft such as the Cirrus Design SR20 and
SR22, Pipistrel Virus and Sinus and the Sting TL-2000 are fitted
with the system at manufacture. Others, such as the Cessna 150/152,
172 and 182 series aircraft can be retro-fitted with these
rocket-assisted recovery parachute systems.
Numerous sport aviation and ultra-light aircraft in Australia are
also fitted with rocket-assisted recovery parachute systems.
Estimates from Recreational Aircraft Australia (RAA) indicate that
there are currently at least six different types of ultra-light
aircraft on the RAA register that are fitted with rocket-assisted
recovery parachute systems. The exact number of sport aviation and
ultra-light aircraft with these installations was not
determined.
An armed and un-deployed rocket-assisted recovery parachute system
presents a potentially serious safety risk to personnel attending
the site of an accident. There is also inconsistent identification
and marking of the hazards posed by the rocket and the associated
equipment on the external surfaces of the aircraft. Any failure to
correctly identify the hazard posed by the rocket at an accident
site could result in serious injury or death.
Cirrus Airframe Parachute System (CAPS)
The Cirrus Design SR20 and SR22 aircraft are fitted with the
Cirrus Airframe Parachute System (CAPS) ballistic recovery
parachute system at manufacture. The CAPS system is manufactured by
Ballistic Recovery Systems Inc. (BRS) in the United States (US).
When deployed in an emergency situation, the system is intended to
bring the aircraft and its occupants safely to the ground.
The system consists of a composite enclosure containing the
parachute and a solid-propellant rocket for parachute deployment, a
CAPS Activation T-handle that is positioned in the ceiling liner of
the cockpit and a parachute harness.
The composite enclosure containing the parachute and rocket
assembly is positioned in the aircraft immediately behind the cabin
baggage compartment bulkhead. The parachute on the Cirrus is
enclosed within a 'deployment bag' inside the box. The deployment
bag stages the parachute's deployment and inflation. A thin
composite cover that is faired into the aft upper fuselage
structure protects the parachute assembly.
The parachute is attached to the aircraft by three harness straps.
The single rear harness strap supports the rear of the aircraft and
is attached to the structure of the rear baggage compartment
bulkhead. The two forward harness straps are attached to the engine
firewall area and support the front of the aircraft following
parachute deployment. Both of the front straps are concealed in
channels beneath a thin composite fuselage outer skin and pass from
the rear baggage compartment below the cabin windows and door
frame.
The CAPS Activation T-handle is positioned in a recess in the
cabin ceiling lining above the front seats. The T-handle is
concealed by a placarded cover that must be removed before the
handle can be pulled for CAPS operation (See Figure 1).
Figure 1: Roof mounted CAPS activation handle cover
For Figure 1 photograph refer to Analyst Notes 2
The CAPS handle is made 'safe' by the insertion of a safety pin
into the Activation T-handle mechanism. The safety pin is normally
removed during the pre-flight inspection of the cabin area. The pin
has a 'remove before flight' tag attached.
To operate the CAPS system in an emergency, the pilot removes the
placarded cover and pulls down on the CAPS Activation T-handle. A
pull force of about 35 lb is required to activate the system.
During the deployment sequence, the rocket forces the parachute
canister up through the concealed composite fuselage cover. As the
parachute inflates, the two forward attachment harnesses are pulled
through their composite covering beneath the fuselage skin.
A warning in the Cirrus's maintenance manual indicates
1:
The rocket exits the fuselage with a velocity of 150 mph in the
first tenth of a second and reaches full extension in less than one
second. People near the airplane may be injured and extensive
damage to the airplane will occur.
Rocket ignition will occur at temperatures above 500o F (260o
C).
Cessna Aircraft
The Cessna 150/152 series of aircraft can be fitted with a
specifically designed BRS manufactured General Aviation Recovery
Device - GARD-150 parachute system. The system uses a rocket for
deployment and is approved for fitment by a Federal Aviation
Administration (FAA) Supplemental Type Certificate (STC). The
rocket deploys the parachute through a fabric covering in the rear
upper fuselage area.
The Cessna 172 and182 aircraft can also be fitted with a BRS
parachute by STC. The BRS installations in these aircraft position
the rocket in the baggage compartment at the rear of the cabin area
and the parachute is ejected through the right half of the rear
window. The forward parachute attachment straps are routed from the
exit point across the upper centreline area of the fuselage beneath
a fibreglass fairing unit.
Sting T-2000, Pipistrel Virus and Sinus Aircraft and
Ultralight Aircraft
The Sting TL-2000 aircraft can be registered on the Australian
civil aircraft register or as an ultra-light aircraft. The Sting
uses the European-manufactured rocket powered Galaxy Recovery
Systems (GRS) installation as do the Pipistrel Virus and Sinus
aircraft. This system is installed in the rear cabin area of the
aircraft and projects the parachute through the rear cabin window
area. Once the parachute has been deployed, the rocket continues
beyond the canopy until the propellant is spent and then falls away
to the ground.
Other ultra-light aircraft use one of several styles of parachute
depending on the type of aircraft. Some of these systems deploy in
an upward direction, while others deploy downward or rearward.
Systems from BRS, GRS and others were identified as installed in
these aircraft. A check of the BRS web-site revealed a list of 100
different mounting installations, in both ultra-light and other
types of aircraft such as hang gliders and gyrocopters.
Information from BRS indicated that some systems made before 1987
used a 'drogue-gun' device for parachute deployment. The
'drogue-gun' utilises a weight fired by a propellant charge to pull
the parachute out of its canister.
Danger markings and accident site safety
There are a variety of warning markings on aircraft to indicate
the presence of the parachute systems. On the Cirrus aircraft there
is a small black text warning that is placed adjacent to the
unmarked exit point for the parachute (see Figure 2). The largest
size text on the warning is about 6 mm high. The Cirrus warning is
not conspicuous and could easily be overlooked following an
accident.
The Cirrus warning decal states the following (see Figure
3):
WARNING!
ROCKET FOR PARACHUTE DEPLOYMENT INSIDE
STAY CLEAR WHEN AIRPLANE IS OCCUPIED
There are no warning markings printed on the rocket motor
canister. There are also no markings on the aircraft's fuselage to
delineate the exit path of the forward harness straps on the
aircraft, or that clearly mark the outline of the concealed hatch
above the parachute.
Figure 2: Side view of rear of Cirrus aircraft highlighting the
CAPS warning decals on fuselage
For Figure 2 photograph refer to Analyst Notes 2
Figure 3: Warning decal on Cirrus aircraft
For Figure 3 photograph refer to Analyst Notes 2
The Cessna 172 BRS system STC includes a requirement for a warning
decal to be placed on the rear window of the aircraft and another
on the rocket canister. The rear window decal has an orange
background and contains the following text:
WARNING
This aircraft is equipped with a ballistic parachute recovery
system
Rocket motor is installed under cover. Remain clear. Factory
sealed unit
Do not open or disassemble. See Airplane Flight Manual Supplement
or BRS
Operators Manual for inspection procedures.
A warning decal sheet supplied with the GRS systems included a
small decal with a directional arrow head that indicated:
ATTENTION
PYROTECHNICAL DEVICE
Keep away from the firing line
Another decal listed warning text detailing some of the dangers of
the system.
The small black text warning on the Virus aircraft GRS system (see
Figure 4) indicated the following:
ATTENTION
EXPLOSIVE
ROCKET INSIDE!
Figure 4: The Pipistrel Virus aircraft and GRS parachute exit
cover
For Figure 4 photograph refer to Analyst Notes 2
A document for Emergency Personnel, that was located on the BRS
Inc. website, indicated that rocket-deployed parachutes have the
potential to cause injuries or death to rescue workers at aircraft
accident sites. The document indicated that the 38 mm by 250 mm
rocket will accelerate to over 160 kph in the first 1/10th of a
second on activation. Similar information is published by Cirrus
Design in a DVD titled Cirrus Airframe Parachute System, Advisory
DVD for First Responders.
The activation of the Cirrus CAPS installation relies on the pilot
pulling on the handle connected to the cockpit roof mounted inner
activation cable. The GRS and BRS units in other aircraft are
similarly activated. During an accident, where the parachute has
not been deployed, deformation of the fuselage can result in the
activation cable being under abnormally high tension, with the
activation device ready to be triggered by any further movement of
the wreckage. This warning is highlighted in the BRS Emergency
Personnel document and in the Cirrus Design DVD.
The BRS Emergency Personnel document and the Cirrus Design DVD
both mention cutting of the activation cable as a method of
temporarily making the system safe. The BRS information strongly
recommends that the cable should only be cut using Felco C16 or
Greenlee Company cable cutters.
Aircraft accident sites can often be contaminated with flammable
materials and with flammable liquids such as petroleum products
following the destruction of integral fuel tanks in wings and
fuselages. Due to the possibility of causing a fire, rescue
organisations, police and investigators need to be vigilant about
the type of equipment used on site, including the use of mobile
telephones. ATSB investigators also use sealed, flash-proof torches
on site for that reason. Any inadvertent activation of a ballistic
parachute rocket motor could present a direct ignition source for
these materials and liquids resulting in danger for on-site
personnel and accident survivors.
ATSB Occurrence BO/200300548
A collision that occurred during landing, which involved a Cessna
C172 and an ultra-light registered Sting TL-2000 aircraft in West
Australia in 2002, highlights the on-site dangers of
rocket-assisted recovery parachutes. During that accident the nose
and propeller of the C172 aircraft had become entangled with the
rear fuselage structure of the Sting aircraft.
The Sting aircraft had a GRS rocket-assisted parachute system
fitted, which had not been deployed. On-site assistance was
received from an expert experienced in the Sting aircraft and its
GRS parachute installation. That expert noted that the GRS's rocket
actuation cable had become entangled with the C172's propeller. He
also indicated that any further rotation of the C172's propeller
may have pulled the cable and activated the rocket. Activation of
the rocket at that point may have deployed the parachute into the
wing of the C172, possibly rupturing the aircraft's fuel tank. With
the assistance of that expert the rocket was removed from the
wreckage and disposed of by police explosive experts.
During the initial post-accident phase, no-one present on site was
fully aware of the imminent dangers they were facing with the GRS
installation.
Sukhoi SU-31M aerobatic aircraft Zvesda extraction
system
While not yet on the Australian civil aircraft register, the
Sukhoi SU31-M aerobatic aircraft utilises a Zvesda light weight
pilot extraction system. This extraction system is a type of
ejection seat and is used to quickly extract the pilot from the
aircraft in the event of a problem.
The pilot extraction system weighs about 15 kg and utilises a
'small' quantity of explosive to simultaneously release the pilot's
safety harness and extend a 5 metre long, 10 cm wide, telescoping
tube. The telescoping tube punches through the cockpit canopy and
extracts the drogue parachute 5 metres from the aircraft. The
drogue parachute then deploys and allows the main parachute to pull
the pilot free of the aircraft. This aircraft has a red, black and
white 'ejection system' decal fixed to the outside of the fuselage
adjacent to the danger area on the aircraft (see Figure 5). That
decal is an immediately recognisable International danger
symbol.
Figure 5: Example of an ejection seat danger symbol
For Figure 5 photograph refer to Analyst Notes 2
Applicable US Federal Aviation Regulation (FAR)
requirements
The Cirrus SR20 and SR22 aircraft are certified for flight in
accordance with the requirements of US Federal Aviation Regulations
(FAR) Part 23.
FAR 23.1541 (a) (2) indicates that an aircraft certified under FAR
23 must contain 'Any additional information, instrument markings,
and placards required for the safe operation if it has unusual
design, operating, or handling characteristics'.
FAR 23.1541 (b) (1) and (2) indicate that each placard must be
displayed in a conspicuous place and may not be easily erased,
disfigured or obscured.
Type Certificate Data Sheet (TCDS) number A00009CH, revision 3,
applies to the Cirrus SR20 and SR22. That certificate, including
any Special Conditions, prescribes the conditions and limitations
under which the aircraft meets the Federal Aviation Administration
(FAA) airworthiness requirements. The Special Conditions listed on
the Cirrus TCDS applies to the ballistic parachute in the CAPS
system and refer to Special Condition 23-ACE-88. Note 2 in the TCDS
indicated that all placards in the Pilots Operating Handbook and
FAA Approved Airplane Flight Manual for the Cirrus SR20 and SR22
must be displayed in the aircraft in the appropriate
locations.
Special Condition 23-ACE-88 indicates that a warning placard is to
be located on the fuselage near the rocket motor to warn rescue
crews of the ballistic system.
Based on the requirements of 23-ACE-88 the manufacturer of the
aircraft had placed the two black-print warning decals adjacent to
the exit point for the ballistic parachute (see Figures 3 and
4).
NTSB and ICAO Concerns
The ATSB contacted the US National Transportation Safety Board
(NTSB) on 9 September 2003 regarding our concerns with the on-site
investigation of aircraft equipped with ballistic parachutes such
as the Cirrus. On 10 September 2003 the NTSB advised the ATSB, in
part, that:
We [NTSB] share your concerns about accident site safety and the
CAPS parachute system fitted to the SR20. We have begun drafting a
safety recommendation regarding [making] the markings visible to
rescue workers at an accident site.
On 11 September 2003, in a response to an approach from the NTSB a
representative of the International Civil Aviation Organization
(ICAO) indicated, in part, that:
... a rocket assisted parachute in an aircraft should definitely
be on a list of possible hazards at accident sites. Also, markings
on an aircraft could perhaps be further discussed with the civil
aviation authorities as it might be a subject within the competency
of FAA/CAAs (rule making).
On 29 April 2004, the NTSB issued six recommendations to the US
Federal Aviation Administration (FAA), the National Fire Protection
Association and the International Association of Fire Chiefs. These
recommendations were numbered A-04-36 through to A-04-41 and are
reproduced below:
To the Federal Aviation Administration:
A-04-36
Revise training guidelines for 14 Code of Federal Regulations Part
139- certificated airports to ensure that airport rescue and
firefighting crews receive training in the recognition and
disabling of aircraft ballistic parachute systems during emergency
operations.
A-04-37
Distribute a safety bulletin to all 14 Code of Federal Regulations
Part 139- certificated airports to raise awareness among airport
rescue and firefighting crews regarding the hazards associated with
ballistic parachute devices during general aviation rescue and
firefighting operations.
A-04-38
Develop standards for the design and installation of ballistic
parachute systems in future general aviation aircraft to enable
emergency responders to quickly and safely disable the system using
only common firefighting tools and examine the feasibility of
retrofitting aircraft that currently have ballistic parachute
systems installed with a system that complies with the new design
and installation standards.
A-04-39
Work with Ballistic Recovery Systems, Inc., Cirrus Design, the
National Fire Protection Association, and the airport rescue
firefighting working group to establish design requirements for
warning labels and exterior markings for airplanes equipped with
ballistic parachute systems that meet the American National
Standards Institutes guidelines (ANSI Z535.4) for conspicuity,
coloration, visibility, and content.
To the National Fire Protection Association and the International
Association of Fire Chiefs:
A-04-40
In cooperation with Ballistic Recovery Systems, Inc., and Cirrus
Design, develop and distribute a safety bulletin to your membership
to raise awareness among
non-airport fire/rescue organizations crews regarding the hazards
associated with ballistic parachute devices during general aviation
rescue and firefighting operations.
To the National Fire Protection Association:
A-04-41
Update existing firefighter training standards for non- airport
firefighting organizations to include information on the
recognition and disabling of ballistic parachute systems.
Information received from the NTSB indicated that the FAA were
working with BRS to develop appropriate training guidelines for 14
Code of Federal Regulations Part 139-certificated airport rescue
and firefighting crews. They also indicated an intention to
distribute a safety bulletin (Cert-Alert) to those personnel.
The FAA is also working with the American Society for Testing and
Materials (ASTM), Committee on Ballistically Deployed Parachutes
for Light Sport Aircraft, to develop a standard for the disabling
of the ballistic parachutes by emergency responders. The committee
is also working on the development of warning labels and exterior
markings that comply with ANSI standards for any aircraft (light
sport) equipped with a ballistic recovery system. The NTSB hopes
that this symbol would be adopted for larger aircraft as
well.
Civil Aviation Safety Authority regulation
requirements
In response to a letter from the ATSB, where advice was sought on
the Australian Civil Aviation Safety Authority (CASA) requirements
for the marking of aircraft equipped with rocket-assisted recovery
parachute systems, CASA indicated in part on 19 April 2004
that:
...parachute systems can only be installed as part of the
certification basis for an aircraft, for example the Cirrus SR20
and SR22, or through the issue of a Supplemental Type Certificate
(STC).
In Australia, the Authority [CASA] accepts a United States of
America (USA) Federal Aviation Administration (FAA) STC as an
Australian approval in accordance with Civil Aviation Safety
Regulation (CASR) 21.114.
The FAA placard requirements are accepted by CASA and the
Authority has no plans to require any additional placards or
markings.
ANALYSIS
Aircraft rocket-assisted recovery parachute systems are a safety
feature. However, there are significant dangers associated with
these systems for persons involved in the immediate aftermath of an
aircraft accident or incident involving aircraft with these systems
fitted. Handling of aircraft wreckage where one of these devices is
fitted, but not deployed, could result in serious injury or death.
Anyone attending an aircraft incident or accident site where a
rocket-assisted recovery parachute is involved needs to be aware of
the dangers.
There are no internationally recognised warning or danger symbols
for aircraft equipped with rocket-assisted recovery parachute
systems. The markings on aircraft should ensure that they
sufficiently convey the extent of the hazards present. The markings
currently placed on aircraft vary and are not sufficiently visible
to immediately draw attention to the dangers. Markings such as the
internationally recognised 'ejection seat' danger symbol are far
more effective at drawing attention to the danger.
Rocket-assisted recovery parachute systems are made in several
countries, including the US and in Europe. Following the issue of
the NTSB recommendations, a warning decal is being developed for
light sport aircraft that are made in the US. However, this will
only apply to US developed 'light sport' aircraft.
There is a need for an immediately recognisable, internationally
recognised, symbol to warn of the dangers associated with a rocket
assisted recovery parachute system. It may be appropriate for ICAO
to examine the development of a standard for such a warning.
SAFETY ACTION
Australian Transport Safety Bureau
The Australian Transport Safety Bureau has now included
information to reflect the dangers associated with the
rocket-assisted recovery parachute systems in the following ATSB
manuals:
- Occupational Health and Safety Manual, Chapter 15;
- ATSB Accident and Serious Incident Investigation Manual,
Chapter 2, Accident Notification Procedure.
The telephone contact details for persons with the appropriate
information about these systems and their disarming has now been
included in the ATSB's internal aviation telephone directory.
The ATSB and the Directorate of Flying Safety - Australian Defence
Force jointly produce a handbook titled, Civil and Military
Aircraft Accident procedures for Police Officers and Emergency
Services Personnel. That publication highlights to police officers
and emergency services personnel, some of the dangers that could be
faced at an aircraft accident site. At the next re-print, that
handbook will be updated to include information on the dangers
associated with the rocket-assisted recovery parachute systems on
some civil aircraft.
The ATSB has undertaken training of its aviation investigation
personnel highlighting the dangers associated with the
investigation of accidents and incidents involving light aircraft
with ballistic parachutes fitted.
The ATSB has purchased several pairs of the Felco C16 cable
cutters and distributed them throughout the organisation for use in
an on-site investigation.
The ATSB has highlighted its concerns about the rocket-assisted
recovery parachute systems to Airservices Australia, Aviation
Rescue Fire Fighting service. Currently Airservices and the ATSB
are collaborating to determine the most effective method to
disseminate that information to all concerned.
Civil Aviation Safety Authority (CASA)
In response to a query from the ATSB regarding the highlighting of
the hazards associated with ballistic parachute systems, CASA
indicated on 19 April 2004:
In relation to the Bureau's concerns regarding the highlighting of
the hazards associated with these devices, CASA has proposed an
amendment to the CASA Aviation Occurrence Procedures Manual to
include instructions regarding investigating aircraft that may be
fitted with an un-operated BRS to incorporate action necessary to
avoid danger from these devices.
The suggested amendment is outlined below.
Title: Warning for possible fitment of
rocket-powered parachute recovery system.
Persons investigating a crashed aircraft should check for the
presence of an unoperated ballistic parachute rocket. The only
known aircraft on the Australian aircraft register at present are
the Cirrus SR20 and SR22, and some small Cessna aircraft
incorporating the system by an STC. Additionally, there may be
aircraft registered with the Australian Ultralight Federation
fitted with such a system.
Aircraft on the VH Register are required to have a warning placard
installed on the fuselage at the exit point, as part of the
certification basis or STC approval. If the aircraft has such a
rocket and it has not been operated, approach with care, do not
intrude into the area marked on the fuselage, do not move the
parachute release if removing persons from the cockpit, and
safe-secure the rocket as per instructions from the manufacturer as
soon as possible.
1. The BRS Inc website quotes an exit
speed of 100 mph. Regardless, the exit speed is significant and
represents a serious danger.