In the accident history of Cirrus accidents, we appreciate the survival of people after a CAPS event due to the innovative safety feature of the Cirrus Airframe Parachute System (CAPS).

When the CAPS parachute system has been activated within design parameters, no one has died and there has never been a post-impact fire.

However, the language we use to talk about these events creates some confusion. In photographs of several fatal accidents, one sees the red/white parachute but wonders if the pilot or others in the plane attempted to use the CAPS parachute system. Most often, those situations involve the rocket firing because of impact forces triggering the ignition mechanism, not by pulling the red handle prior to ground impact.

This is my attempt to clarify the language we might use to describe what we know about CAPS events.

  • CAPS event -- any time in flight when the CAPS system is activated, or attempted to be activated, before ground impact
  • CAPS pull -- a CAPS event with evidence that someone in the cockpit pulled the red handle prior to ground impact
  • CAPS save -- hmmm ... when someone survives a CAPS event, but this requires some additional distinctions.

To clarify when a CAPS event can be considered a CAPS save, we need to investigate the circumstances of the accident. Sometimes, the wreckage shows clear evidence that the parachute was activated after ground impact, hence, had no effect on the crash sequence, and could not be considered a save, even if there were survivors. Here's an example photograph of a crashed Cirrus with the parachute stretched out when the rocket ignited due to impact forces on the ground. Unfortunately, all occupants died in the crash.

Typical arrangement of a CAPS parachute stretched away from the wreckage after the rocket ignites from ground-impact forces and extracts the parachute, which never inflates but falls to the ground still folded. Wreckage photograph from fatal accident #30 in N482SR at Faribault, MN on 25 November 2007.

The determination from photographic evidence and reports from investigators helps identify when and how the CAPS parachute system was activated, whether the parachute deployed, and whether anyone survived the accident. Consider these distinctions:

  • CAPS activation how -- the rocket and parachute system activates either by a pull of the red handle in the cockpit, by impact forces, or by fire

Note that a pull of the red handle may be by anyone in the airplane, normally the pilot, but in two CAPS saves, the handle was pulled by the right-seat passenger (Indianapolis, IN; and Bull Bay, Jamaica)

  • CAPS activation where -- whether the CAPS system activated in the air prior to any impact, after first impact but before the ground, or after ground impact

Note that activation after the first impact with a tree has happened at Porter, TX and Asturias, Spain, which was obviously at a very low altitude. In both cases, the parachute had no effect on the outcome and did not fully inflate.

  • CAPS airspeeds -- whether outside or within design parameter of airspeed less than 133 KIAS

Note that five activations above 133 KIAS have been recorded, and only one at 300+ KIAS was fatal (Norden, CA). Otherwise, people have survived activations at airspeeds of 168, 170, 187 and 190 KIAS at Haverstraw, NY; Mathias, WV; Horton, UK; and Bennett, CO respectively.

  • CAPS altitudes -- whether outside or within design parameters of loss of altitude of 400 feet in level flight or 920 feet in a 1-1/2 turn spin/dive

Note that to date, in every CAPS activation within design parameters, all aboard have survived. In a few cases, activation below 400 feet has been survivable (Idabel, OK at 336 feet AGL, and New Orleans, LA reported at 300 feet above Lake Ponchartrain).

  • CAPS deployments -- whether complete, partial, never inflated, or failed

Note that testing and recorded data confirms that complete parachute deployment requires 8 seconds from rocket ignition to parachute extraction and opening regulated by the slider to firing of the line cutters and disreefing the rear riser to level the aircraft under canopy. Partial deployment might occur when not enough time occurred prior to ground impact or when the parachute was extracted but never inflated sufficiently to activate the line cutters or when the line cutters failed to disreef the parachute. In all accidents to date, investigators found some examples of the first two scenarios and no examples of the line cutter failures.

  • CAPS survivors -- the number of people who survived

Note that in extreme scenarios when the parachute only partially deployed after activation too low in a spin, the impact forces could cause fatalities. The pilot in the Indianapolis accident died while his three passengers survived after activation just 4 seconds prior to impact at 528 feet AGL in a 3-1/2 turn spin, as determined from recorded data.

We can now define a CAPS Save as an event in which CAPS was activated and the deployment was either complete or partial and people survived. Essentially, a CAPS save occurs when someone survives an accident where the parachute affected the outcome.

This gives rise to numerous edge cases, such as these.

Lexington, KY: not a CAPS save because the parachute did not activate prior to ground impact. The pilot stated on the radio his intentions to pull CAPS but it was never activated; the pilot successfully executed a forced landing and a witness describes the plane coming to a stop and then the parachute fired; obviously, the CAPS system worked, just not while in the air. My speculation is that either the pilot used an incorrect technique or the CAPS cable routing was improper, which had been subject to two service bulletins issued prior to this flight but only one of the two had been complied with on the accident airplane.

Norden, CA: not a CAPS save because the parachute ripped off the airframe and the pilot did not survive. The pilot reported icing and lost control in a high-speed dive, which engineers estimate at over 300 knots. The parachute activated but did not successfully inflate at that high airspeed.

Indianapolis, IN: a CAPS save despite a low-altitude deployment and the fatal injury to the pilot. The passenger activated the parachute according to interviews. The recorded data shows activation at 528 feet AGL just 4 seconds before impact. However, the parachute decelerated the plane as it descended prior to ground impact with a water retention pond in a residential area.

Sydney, Australia: not a CAPS save because the rocket took an anomalous trajectory and failed to extract the parachute. This activation was at a very low level, estimated to be 90 to 120 feet AGL, during a forced landing attempt on a motorway. An Airworthiness Directive was issued to improve the pickup collar that might have misalignment between the rocket and the parachute bridle.

Deltona, FL: not a CAPS save because the parachute was activated at too low an altitude to have an effect and both occupants died. The plane entered a 10-turn spin during slow-flight practice and witnesses describe the parachute coming out about 200 feet above the ground, however, no deceleration was noted in the recorded data, so the activation was likely very close to ground impact.

Boulder, CO: not a CAPS save because investigators determined that the activation was due to impact forces of a mid-air collision and both occupants died. The plane hit a glider tow-plane at a 90-degree angle at cruise speed and the parachute deployed and lowered the burning wreckage under canopy. What was remarkable was that at least three people on the ground captured the descent on video, which was repeatedly shown on newscasts around the world.

Porter, TX: not a CAPS save because the parachute, while activated and deployed never inflated and never affected the outcome. The pilot failed to gain altitude during a go-around and pulled the red handle after first impact with a tree, but so low and so close to ground impact that the 90-foot risers extended the parachute but it never inflated or decelerated the airplane.

For a full listing of CAPS events, please see Cirrus Airframe Parachute System (CAPS) Deployment History

For the current count of CAPS saves, please see this page.

 

Cheers
Rick