Engine Failure

[Fuji Abound]

I am also no expert but I have taken an interest in this matter.

There are a number of factors that will determine the outcome of a forced landing. However, reading the accident reports, it strikes me that with conventional forced landings the single commonality is the lack of predictability. That makes sense to me. I suspect we all think about forced landings in the relatively sterile training environment. In reality there is every chance the engine will probably fail when we are least expecting it to do so.

From my limited experience, discussions with those who have had engines fail, and from reading the accident reports a lot of engine failures are at relatively low levels. Statistically this is not surprising because so many pilots usually operate between 1,500 and 3,000 feet. Catastrophic engine failure is often, not surprisingly, associated with some sole searching. For example, a pilot I know had oil all over the screen and almost no forward visibility. There are a host of reasons why in advance of a failure and for a time after the failure, it is all too easy for the pilot’s vision to have tunnelled, such that he has lost some of his situational awareness. He must now prepare for the landing and select the best landing site as well as maintain control of the aircraft. Again this is barely representative of the normal sterile training environment in which the pilot is expecting a PFL, has thought about wind, has rehearsed the vital pre-landing actions and, as luck has it, is almost certainly over a area that will present some reasonable landing opportunities.

To put it simply you are lucky if a forced landing occurs in ideal circumstances and you are truly current if you are able to totally avoid tunnel vision and correctly prioritise the vital tasks. I would suggest that is not representative of the average GA pilot flying less than 50 hours a year, and may not be representative of many pilots flying a lot more hours.

Moving on, the wind has been assessed, although perhaps not that well or without adequate thought to the variation in direction or strength at the bottom of the valley with which we are confronted, and a field has been selected.

Everything now depends on maintaining control and arriving where we intend. Over the years I have enjoyed taking part in spot landing competitions. At some you can stand with the other onlookers almost in the box. It is interesting to see how many pilots new to the game fail to even get there wheels in the box – and that is with the availability of power. Inevitably some types are much more difficult to spot land accurately – in fact the very types many pilots commonly fly.

We can all recall the tips we were given about field selection – and they are in the main sound. However find me a field that turns out the way you would have wished form 2,000, by which many pilots will have committed to the landing site. I think we all realise that there are many hazards which we may not have anticipated.

As to the landing, yes of course in ideal circumstances we slide across Bowling Green grass in an exactly horizontal plane until eventually the aircraft comes to rest of its own accord. Yeah, right. The reality is likely to be different, and it is likely to involve some degree of impact damage involving both horizontal and torsional forces some of which may be high. Both the aircraft and its occupants are ill prepared for these forces. We all understand that very little thought was given to the design of the vast majority of light aircraft to energy absorption. How many light aircraft have air bags, crumple zones, roll bars and don’t have all sorts of sharp and protruding panel work almost designed to impale or prevent your egress?

A reasonably sound resume of the effect of deceleration on the human bodies appears here:

http://ftp.rta.nato.int/public/PubFullText/RTO/EN/RTO-EN-HFM-113/EN-HFM-113-03.pdf

and is worth reading. If anyone is interested I have more detailed material. We believe the body is better able to withstand axial loads than horizontal rotational loads which are more than likely in a typical forced landing (other than the greaser along the apocryphal Bowling Green). An analysis of rotary accidents suggests spinal injury is no worse than in fixed wing accidents, surprising in itself given that in the typical rotary accident the vertical rate of descent and the absence of energy absorbing technology results in significantly greater loads being transmitted to the pax.

IO I am aware of the tests to which you refer. However with respect I cant imagine they are representaive of the impact loads in a typical forced landing because the aircraft is unlikley to be running along the ground in a single plane but more likely to be subjected to some "tumbling". Moreover how many pilots find themselves tightly strapped to their seats by means of a "proper" five point ratchet harness.

So, to sum up, for the average pilot, who at best is likely to find himself dealing with his worst nightmare while lacking in the currency to achieve better than a pedestrian forced landing an engine failure is a real threat to his and his passengers. For the pilot who considers himself current, he may still need a healthy dose of luck or live to regret as he descends through IMC into the mountain valley painted on his GPS, that the terrain at the bottom of the valley was at least as good as he hoped and the winds aloft had not turned into a stonking 20mph tail wind.

I don’t want this to sound like a Cirrus PR campaign, because it isn’t. However it does reflect my thoughts on why ballistic parachutes and cockpit design are vital as a means of improving on average the survivability of a forced landing. Yes, with luck the outcome of many forced landings is very good. However, I would rather we take luck from the equation. By doing so that means we give the average pilot experiencing an engine failure above the sort of terrain and in the type of conditions we could reasonable expect him to be operating the best chances of survival and the least injury.

I also think for an aircraft with a BP I am comforted by the predictable arrival this should ensure. I know with almost certainty that I will land with a vertical velocity of less than 20 mph. I know that the energy absorbing material will do its job. I know that it is very unlikely any of the forward facing elements of the cockpit will impact on me, or hinder my egress, I know there will not be any surprises that I hadn’t spotted when I turn final, importantly I know that I have got maximum time during the descent to organise myself and my pax to best improve their chances. For all of these reasons I think a chute is almost always the best option. I think the injury record in every successful Cirrus deployment speaks for itself.

Please persuade me otherwise – I would be truly interested.

At the moment I will take the predictable 3G any time.