Safety Editor, Nick Heard, gives his advice on when to deploy a Ballistic Parachute Recovery System
12 December 2022
Passing 1,400ft in a descent towards an airfield the engine started to run roughly, and subsequently lost power. The pilot turned the aircraft parallel to the shore and deployed the aircraft’s Ballistic Parachute Recovery System (BPRS).
The parachute descent was successful and both occupants escaped from the aircraft uninjured. The loss of power was probably caused by fuel starvation to the engine, but the cause of the starvation could not be determined.
The Cirrus SR22 is equipped with a whole-aircraft BPRS, proprietarily called the Cirrus Airframe Parachute System (CAPS). The following are extracts from the Pilot’s Operating Handbook (POH) description of the system:
‘The CAPS consists of a parachute, a solid-propellant rocket to deploy the parachute, a rocket activation handle, and a harness embedded within the fuselage structure.
‘When the rocket launches, the parachute assembly is extracted outward due to rocket thrust, and rearward due to relative wind. In approximately two seconds the parachute will begin to inflate.
‘Following any nose-up pitching, the nose will gradually drop until the aircraft is hanging nose-low beneath the canopy. Eight seconds after deployment, the rear riser snub line will be cut and the aircraft tail will drop down into its final approximately level attitude. Once stabilised in this attitude, the aircraft may yaw slowly back and forth or oscillate slightly as it hangs from the parachute. Descent rate is expected to be less than 1,700fpm with a lateral speed equal to the velocity of the surface wind.
‘The Cirrus Airframe Parachute System (CAPS) is designed to lower the aircraft and its passengers to the ground in the event of a life-threatening emergency. However, because CAPS deployment is expected to result in damage to the airframe and, depending upon adverse external factors such as high deployment speed, low altitude, rough terrain or high wind conditions, may result in severe injury or death to the aircraft occupants, its use should not be taken lightly. Instead, possible CAPS activation scenarios should be well thought out and mentally practiced by every SR22 pilot. The following discussion is meant to guide your thinking about CAPS activation. It is intended to be informative, not directive. It is the responsibility of you, the pilot, to determine when and how the CAPS will be used’.
The POH offers a range of scenarios in which the use of the BPRS is suggested. One of those is as follows:
Landing required in terrain not permitting a safe landing
‘If a forced landing is required because of engine failure, fuel exhaustion, excessive structural icing, or any other condition CAPS activation is only warranted if a landing cannot be made that ensures little or no risk to the aircraft occupants. However, if the condition occurs over terrain thought not to permit such a landing, such as: over extremely rough or mountainous terrain, over water out of gliding distance to land, over widespread ground fog or at night, CAPS activation should be considered’.
The event began at a relatively low altitude of 1,400ft amsl, so little time was available to the pilot to action drills and attempt to resolve the engine issue. By the time the pilot had informed Lee-on-Solent of his situation and attempted a fuel tank change, the aircraft had descended to 800ft amsl.
The pilot attempted another fuel tank change, but this still had no effect. Believing that he would be unable to glide to land, the pilot deployed the BPRS in accordance with the training he received for engine failures in Cirrus aircraft, and the last altitude he recalled seeing was approximately 600ft amsl.
Data retrieved from the aircraft indicated that the BPRS was deployed descending through 340 ±20ft asl.
The cause of the accident – which was related to fuel management issues on the Cirrus – is not the subject of this month’s analysis.
What I want to look at is the use of the Ballistic Parachute Recovery System (BPRS), which led to the aircraft ditching in the Solent.
The Cirrus aircraft was perhaps the first aircraft to integrate BPRS (known as CAPS on the Cirrus) into its design. Many other modern light aircraft designs have now adopted BPRS, and there is lots of evidence detailing that it is a popular and reassuring safety device to have on board. Many lives have been saved by using BPRS, although not all BPRS activations have led to successful outcomes.
I spent most of my RAF career flying aircraft that were fitted with Martin-Baker ejection seats, and I’m happy to report that I never had to use one ‘in anger’, unlike many of my colleagues.
Ejection seats were superbly reassuring within military flying, with many thousands of lives saved – including in combat operations, where ejection seats extricated aircrew from mortally damaged aircraft.
However, ejection seats are utterly lethal if used at the wrong moment so safety procedures had to be followed meticulously.
Of particular importance was the need to eject within the safe parameters of the seat design – speed, height, rate of descent, bank angle, etc. Ejecting outside seat parameters would almost certainly lead to fatal results. The mantra in ejecting from an aircraft was therefore very much: ‘Eject in time’.
This brings me onto the relevance of ejection seat use with regard to BPRS. BPRS gives pilots and passengers a safety net that just did not exist some years ago, but it is by no means a system that will save lives in each and every airborne emergency situation.
Careful thought should be given to the advice given by BPRS manufacturers about use of the system.
As ever there are many factors that may influence the decision to use BPRS in flight. An engine failure may not necessitate BPRS activation unless there is clearly nowhere to land (as in the situation above where a traditional ditching into water from forward flight would probably have been less favourable than the BPRS ditching).
Descent into inhospitable terrain with a failed engine (perhaps northern England, Wales or Scotland) may suggest use of BPRS in the absence of a suitable landing site. An engine failure above cloud or at night may well make BPRS the best option.
Loss of aircraft control and associated excess airspeed may lead to a desperate activation of BPRS but there are major issues with this. Many BPRS units have maximum speeds for operation, which are typically close to the normal cruising speed of the aircraft.
BPRS activation imposes massive strains on the airframe and usage beyond the safe design speed of the system may merely cause the system to fail catastrophically due to excess aerodynamic loads (remember ‘V-squared’ during PPL ground school?), leading to unknown results.
Whatever the airborne emergency, pilots flying BPRS aircraft must make a timely decision about when to activate it in order to remain within the design parameters of the system – just like ejection seats.
In the accident discussed the pilot nearly left it too late to activate CAPS by attempting fault rectification for too long – the full sequence of parachute operation had not been completed as the Cirrus hit the water, leading to a nose-down attitude on impact. This would have been outside design requirements and could have been very dangerous.
Using BPRS is quite a decision to make: the aircraft will almost certainly be written-off and pilot owners may not wish to lose their prized possession.
However, aircraft can always be replaced whereas people cannot. So I would recommend a similar mantra to ejection seat use for pilots flying BPRS aircraft: ‘Activate in time’ – don’t leave it too late!
