It is possible that those of you who are reading this article have not yet flown in a Cirrus SR20 or SR22, but most likely you have already heard about this single-engine plane that popularized the term “plane with parachute”. By the way, every time I am asked which aircraft I fly and I mention its name, many lay people do not the model itself, but when mentioning that the aircraft has a parachute, a face of astonishment with curiosity quickly appears, and, of course, a flood of questions about how it works – not to mention questions about why they don't install the same system on commercial aircraft they travel on (but that's a topic for another article).
Check out a FULL review of the Cirrus equipped with this system:
The equipment, known as CAPS (Cirrus Airframe Parachute System) is nothing more than a parachute system that allows the aircraft with all occupants inside to return to the ground in a controlled and safe way. Such a system helped the manufacturer Cirrus Design (from a few years ago called Cirrus Aircraft) to popularize its single piston engine in the aeronautical environment.
The fact that the Cirrus have an extra layer of security (or, as I usually say, one more chance), filled the eyes of lovers of other brands to prefer the modern plane, making it sell like hotcakes against competitors, already established . This is so true that the company has led the sale of aircraft of this class for years, making it possible for them to recently celebrate the milestone of 8000 Cirrus SR20 / SR22 sold. A record, in of quantity in a short time.
Even if you fly other aircraft models (or will fly), it is interesting to understand a little how this device was developed, how it works, its limitations and other curiosities – because, very likely, you will still fly in one of them. After all, with no competitors at the height so far, the good sales of this series of planes remain firm, with the Brazilian market being the most important for the automaker, second only to the North American one.
THE PURPOSE AND DEVELOPMENT OF CAPS
The development of the system took place, at least officially, due to a need that the company identified in the market at the time for greater safety in single-engine aircraft, especially after an accident that occurred in 1985 with Alan Klapmeier (one of the founders of Cirrus Design), where his The plane had lost more than one meter of wing and part of the aileron after a mid-air collision with another aircraft, killing the other pilot. After this scare, the Klapmeier brothers decided to develop a device that could bring the aircraft back to the ground safely.
In addition to this fact, it was speculated in the aeronautical environment that such a device was also developed due to the fact that the SR line had a lower glide ratio than the aircraft on the market at that time, due to the wing having a more slender, “thin” profile, which favored greater speed to the detriment of a greater glide ratio, unlike the Cessna 172, Beech Bonanza, etc., its competitors, and which could encounter some difficulty at the time of an engine failure and certifying the plane with the FAA (Federal Aviation istration) and other entities around the world. The manufacturer, however, denies this fact.
The development of the parachute system began in the mid-1990s as an adaptation to one already under development called GARD (General Aviation Recovery Device), in a partnership between Cirrus Design and Ballistic Recovery System (BRS) for Cessna 150 aircraft, the first test took place in 1998 in the Southern California desert. After fulfilling the seven in-flight test, carried out by Scott Anderson (former F-16 pilot and test pilot of the brand), all with success, Cirrus received the certification of the project by the FAA, starting, from 1999, to equip the first production Cirrus SR20.
CAPS COMPONENTS
The main parts that make the system work are:
• T-Handle – is a “T” shaped handle located on the ceiling, between the two pilots, but easily accessible to everyone in the cabin. It is she who activates the system, as it is connected by cables to the actuator, behind the luggage rack, where the parachute is located. It has a safety pin, which prevents activating the CAPS inadvertently, and must be removed during the pre-flight checklist.
• Actuator – device that intermediates the activation of the T-Handle with the ignitor/rocket. Through a spring-loaded device, it triggers an electrical signal to ignite the rocket.
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Ignitor / rocket - is an engine (rocket) consisting of the engine case, solid propellant, oxidizer and nozzle. Its function is to extract the parachute out of the plane, through rocket action.
• parachute – is responsible for the descent of the plane to the ground, through air resistance when inflated. It is accommodated inside a parachute bag on the back of the aircraft overhead bin.
- slider of the parachute - it is a piece in the form of a ring with several holes around it, which has, among other functions, to control the opening of the parachute through the "slip" of this piece on the parachute rigs.
• Suspension lines – these are cables connecting the aircraft structure (2 tied in the engine cradle region and 1 at the rear of the luggage compartment) and which connect the parachute to the aircraft, ing it during the descent.
DRIVE AND OPERATING PRINCIPLE
When facing a situation of imminent danger, and being below the Vpd (CAPS deployment speed, between 133 and 140kt depending on the version), the pilot activates the system by pulling down the T-Handle, which is connected to the Actuator, with a force of at least 45lbs (20kg). There, the actuator will fire an electrical signal to the Ignitor head. From here, the operating principle is the same as that of rockets: the ignitor will cause the solid fuel to ignite (composed of propellant and oxidizer) which will raise the temperature of this fuel to more than 3000°C, where the gases from this combustion will be expelled by nozzles (nozzle) at a speed of Mach 6, pulling out the box containing the parachute. This whole process takes about 2 seconds.
At the time of extraction, to reduce the speed and “Gs” forces between the rocket and the parachute box, an “accordion” rope called bridal incremental it will stretch, allowing the decrease of the speed and force of inertia between the box and the bolide. Once out of the air, the box allows the parachute to be opened, having its speed and opening diameter controlled through the slider of the parachute, which will "slip" from the closest point of the parachute to the plane's fuselage, to allow a more homogeneous inflation.
Once inflated, two devices called cutter lines will break a nylon rope that will release the cable attached to the luggage rack, which will leave the plane in the ideal attitude for landing (from ≅10° pitch down). The descent occurs at a rate of approximately 1700FPM, equivalent to an aircraft freefall from a height of 13ft (4m). From the moment the T-Handle is engaged until the parachute is fully deployed, Cirrus reports a demonstrated altitude loss of 400ft (up to G3) or 560ft (G5 onwards).
In order to ensure the integrity of the occupants when the CAPS system is activated, the Cirrus has landing gear designed to absorb a large part of the impact force, added to this the internal structure of the seats are of the type honeycomb, where this type of seat offers greater protection to the spine, since at the moment of impact it can receive a force of up to 19 Gs.
Finally, seat belts with airbags on the sides closest to the doors allow for greater protection in cases of impact against windows and columns close to the sidesticks, added to the structure with programmable deformation, makes the aircraft of the SR20/SR22 line extremely safe.
WHEN TO USE THE SYSTEM?
The equipment was designed to be used at any time the pilot deems most convenient, especially when his survival is at imminent risk. However, as there are countless situations for accidents to occur, we must bear in mind that there are two scenarios where this activation may be necessary:
1 – activate CAPS immediately:
– in-flight collisions
– screws
– loss of control
– engine failure between 500/600ft and 2000 ft AGL
– there is no survival alternative
2 – Consider enabling CAPS:
– engine failure above 2000ft AGL
The cases in the first scenario are very simple to understand, requiring little explanation. As for the second, it is convenient to that there is a “Decision Altitude”, which is a theoretical height of 2000 ft recommended by the factory where the pilot will have to make a decision before arriving at it. This height aims to ensure a vertical layer of safety where the CAPS will have time to be activated and properly inflated (when activating the system from 2000 ft, the aircraft takes approximately 1min to reach the ground).
An example: suppose you are flying at an altitude of 10.000ft and your Cirrus engine stalls. You will be able to use the best glide speed (found in the manual for your airplane version) while gliding to an ideal spot for a hard landing, such as a runway. While navigating to that location, reading the manual, there is a possibility that restarting engine, if time permits. In the positive case of reactivation before this height of 2000 ft, the unnecessary use of the parachute will be avoided.
Otherwise, in this same scenario and the engine cannot be restarted, the pilot will have an altitude of approximately 8000 ft AGL until reaching the altitude limit of the “Decision Altitude” where the CAPS must be activated. During this descent, it is highly recommended to perform the CAPS Activation Checklist, preparing aircraft and occupants for touch down.
Another situation that can occur is when the engine fails after takeoff. According to the company, the system will be available (the famous term CAPS AVALIABLE) for heights above 500 ft AGL (up to G3) and 600 ft (G5 onwards, due to higher takeoff weights). Therefore, one of the instructions I always apply to students and/or owner pilots is to add these values to the airport elevation during the pre-takeoff briefing. Example: if taking off from Campo de Marte (SBMT), whose runway ELEV is 2.371 ft, speak verbally “CAPS available – 2.870 ft”. This means that, in a situation of engine failure after take-off, where time is short, the specific opening value of the parachute for your Cirrus version is already in mind, avoiding calculations at an inopportune moment.
ing that being below the opening height of the parachute during takeoff, the golden rule of aviation remains the same: breakdown with available runway ahead – landing with full flap on the runway. No runway ahead – landing ahead, preferably on the windward side, avoiding obstacles with curves of at most medium inclination. Do not attempt to return to the runway.
WHAT ENGERS SHOULD KNOW?
It is also very prudent to hold a briefing with engers flying the machine for the first time on the procedure to be carried out in a possible emergency situation. pilot incapacitation, when there is a collision with large birds, loss of consciousness or even collision with another aircraft on the pilot side.
In this case, it is convenient:
• briefly describe the system
• teach how to cut the engine through the mixture (aiming to reduce the machine speed below the Vpd and also to avoid going into an abnormal attitude)
• make sure your belts are tied
• pull the T-Handle
• unlock the doors (if there is time)
• hold both legs with the hands held by the fists on the knees
After touchdown, teach to:
• use the hammer placed inside the object holder between the seats, breaking the window – in case the door has closed or is stuck due to some torsion in the plane's fuselage
• move away from the plane on the side that blows the wind, thus avoiding being covered by the parachute
• if there are no people who can help, and there is no risk of fire, assist in the removal of other occupants
With this information for engers, the purpose of the system will be even more assured.
SYSTEM EFFICIENCY
The first activation of the CAPS system after the start of sales occurred in 2002, in Lewisville, Texas, due to an engine breakdown. The pilot was unharmed aboard his SR22.
This was one of the 122 times the device was activated (until May 2021), with 104 activations being successful. Among this difference (18) are computed cases where the equipment was opened outside the speed and height parameters, in addition to situations where the device was inadvertently activated on the ground, post-impact fires and other reasons. In 2018 alone, 19 aircraft that triggered the system were put back into service.
Finally, of these 104 successful activations, with 212 lives saved using the Cirrus Airframe Parachute System, makes Cirrus Aircraft the holder of the best safety records in the aviation industry worldwide, demonstrably. Quite an achievement, which raises the confidence of those who fly a Cirrus.
