Aircraft accidents AIrcraft to blame?

[Pace]

This year has started off in a bad way with a number of fatal and tragic accidents culminating in the latest one which is extra awful as it appears to have involved young people.

Many of our light aircraft are 20 30 40+ years old. Yes we have advanced in leaps and bounds with avionic advancements.

With a car the development has involved deformable structures, engines that go below the passenger compartment and airbags. In racing cars fuel cells which dont catch fire.

The engine on an aircraft is held by a few alloy tubes and there is nothing to stop the mass of engine metal joining you in a headon.

What more can be done to protect pilots from pilots. Cirrus must be commended for their work on ballistic shute recovery systems and vertical impact seats plus airbags.

What can we safely do with older aircraft to make them safer to their occupants if anything or is it all down to pilot training?

Another very sad day.

Pace

[IO540]

I think that if you have a wing or elevator come off, there is nothing that can be done - short of a BRS chute - because the descent is at about -3000 to -20000fpm i.e. 30 to 200kt VS which is going to be fatal. And you will get the 30kt end of this range only if the wreckage is spinning down.

For lower energy impacts, the huge trend towards ultralight/sports machines makes it much harder to provide any protection because those things are so flimsy. I know their supporters say they are tested to +6g or whatever and I am sure that is strictly correct but it is obvious when looking at one that there is little or no impact protection and there cannot be much within the weight limits. The only safety comes from their substantially lower stall (landing) speeds.

Today's sad accident looks like yet another very low level midair - the UK gets on average one a year. The best protection is to fly as high as possible and certainly above about 2000ft.

[AJMortimer]

Not necessarily the case ... ?! LOL

YouTube - Full Scale Wing falls off (http://www.youtube.com/watch?v=AEyw6X1DqFs)

AJ

[IO540]

That one is a fake. Done to death all over the internet :)

[matt_hooks]

IO540, the +6g rating relates to normal flying conditions. Modern aircraft have very good impact ratings. The Diamond DA40 offers protection to 1000g acceleration, as I believe does the DA42.

The Grob is a relatively modern aircraft.

As with everything in aviation, it is a trade off. It's easy to add extra protection to a car, where weight affects only acceleration and fuel efficiency. With an aircraft, every extra kilo of weight added profoundly affects the flying characteristics. This is why aviation is usually at the cutting edge of materials technology. Modern aircraft materials are so far removed from what was in use 20 years ago as to be a completely different beast.

So yes, I would say that modern aircraft are FAR safer than those made a few years ago.

Of course, due to the high cost of buying and maintaining an aircraft, in comparison to that of a car, aircraft will tend to remain in service for longer. Of course, with an aircraft, very sensibly, most of the effort goes into ensuring that the accident doesn't happen in the first place, as a light aircraft accident, no matter what protection you have, is unlikely to be survivable. Therefore all the design and statutory effort goes towards preventing crashes in the first place, by having very high standards of maintenance, and by providing thorough training and regular assessment of the pilots.

It is unfortunate that we have experienced several fatal general aviation accidents in the past few months, but the numbers are still incredibly low on comparison to the number of flights, and flight hours, and anything else you choose to look at.

[B2N2]

1000g acceleration, as I believe does the DA42.
Uh........no
The cockpit area of the DA-40 and the DA-42 has been rated to 26 G impact resistance. One of the reasons as to why the seats are not adjustable.
Here is an interesting video of the " AMSAFE" airbag seatbelt system:

YouTube - Diamond DA40 AmSafe L (http://www.youtube.com/watch?v=jbdOSHgJ3LE&feature=related)

[Pace]

The airbag video was interesting but I noted there was no engine or forward crash visible just a bag deployment.

A twin is far safer in a head on collision than a single.

The biggest killer in a single is the fact that there is little to restrain the massive block of the engine from coming back through the firewall into the cockpit.

In a modern car the engine is directed down away from the passenger area. Not so in a light aircraft.

For that reason the airbag while a great addition is not going to help much against a few hundred pounds of solid metal joining you in the cockpit at 30 mph plus.

Pace

[IO540]

Some data on midairs: from here (http://www.aaib.gov.uk/cms_resources/Luscombe%208E%20Silvaire%20Deluxe,%20G-AKUI%20and%20Pacific%20Aerospace%20PAC%20750XL,%20ZK-KAY%2002-09.pdf) we have

Following a previous mid-air collision, a CAA working group reviewed the recent history of mid-air collisions between recreational aircraft. The review determined that UK-registered aircraft had been involved in a total of 30 mid-air collisions in the period 1995 to 2004, resulting in 27 fatalities from 14 fatal accidents. Thus, collisions averaged three per year, and roughly half of the collisions involve at least one fatality.

[Pace]

More of a case to retrofit ballistic shute systems to aircraft which are suitable and for current manufacturers like Diamond to follow Cirrus?

Airbag technology could also be looked at not just for collision protection but maybe also for water ditching?

If an aircraft was a car it would never be licenced

Pace

[matt_hooks]

If it was as easy to get in an aircraft and fly it as it is to get in a car and drive it, then I would agree that the crah safety standards should be the same. However, in the aircraft industry, the efforts are concentrated on prevention rather. This is why anything involved undergoes rigorous testing and regular inspections. This is as true for the pilots as it is for the aircraft. Our training and preparation is far removed from the amount of training a car driver gets. And we are under constant checking and verification.

Also, aircraft undergo rigorous checking and testing, as do the great guys who maintain them.

I don't think the weight penalty of impact protection systems, and the financial penalty in terms of getting a new system trialled and approved, and the on cost, would prove to be worthwhile.

The number of people killed is, still, extremely small. And whilst every death that can be averted is obviously a worthwhile goal, as with all things in aviation it comes down to the trade off.

Someone in another thread said today "nothing that is worthwhile can ever be 100% safe". Whilst I can see this is no comfort to anyone who has lost friends and/or family, the tota numbers killed are so vanishingly small that I think we have the approach just right.

[Pace]

I don't think the weight penalty of impact protection systems, and the financial penalty in terms of getting a new system trialled and approved, and the on cost, would prove to be worthwhile.

Crash protection is not really about weight. Take Formula 1. The cars became faster lighter and the crash protection amazing with modern formula 1 technology.

Cirrus are dipping their toes in the right direction I would like other manufacturers to follow suit and to make aircraft which protect pilots from themselves.

Pace

[matt_hooks]

In formula One you have, effectively, a "money no object" situation. In the aviation environment, the cost is very definitely an object.

[Karl Bamforth]

There is little to compare an aircraft with a car, its like apples and oranges. The risk in a car is much higher with other cars going the opposite way just a few feet away and if you stray off track by more than a few feet and you will crash into a barrier or building.

The problem with ballistic chutes and airbags is the risk of accidental activation.

The only real use I can see for a ballistic chute is mid air or structural failure. Both are very rare occurences that probably would compromise the airframe to a point where it wouldn't withstand the forces generated by the chute deployment.

Likewise airbags, if it was faces hitting control yokes that was killing pilots I would agree, but I think you will find it is general impact forces and fire that is the big threat.

[B2N2]

For that reason the airbag while a great addition is not going to help much against a few hundred pounds of solid metal joining you in the cockpit at 30 mph plus.

That all depends on the impact obviously, an airbag can only do so much.
So if that is a fair argument is open for debate.
Is surely helped in this accident:

http://pilotsafetynews.com/images/plane_crash_8-17_t637.jpg

[bjornhall]

The biggest killer in a single is the fact that there is little to restrain the massive block of the engine from coming back through the firewall into the cockpit.

Interesting. What data is the assessment based on? Since another prevalent school of thought suggests the engine in a single protects the occupants, due to the far stronger nose structure that is necessarily in place to support the engine during normal operations. In a twin the nose is a light and flimsy aluminium or plastic design with no protective ability whatsoever.

There should be ample data from crash investigations, and studies of that data, to suggest what the main causes of injury in light aircraft crashes are. From the data, it should be fairly straightforward to conclude what the most effective improvements would be.

So in discussions like this one, where is that data?

On the other hand, if light aircraft (passive) crash safety were mainly a sales pitch, the lack of supporting data would be understandable...:E

Regarding the comparison with formula 1, vertical impact speed is generally not a problem in formula 1 crashes. Reducing vertical impact forces, thus lowering the risk of crippling or fatal spinal compression injuries, is a large part of what modern increased crash safety aviation seats (in light aircraft!) are about. That is why we can't put our knees on the seats anymore, or put stuff underneath them...

Passive crash safety would be the last thing I'd be looking for in selecting an aircraft.

[gasax]

I think bjornhall is on the right track. I've had a close look at at least 8 serious crashes of light aircraft. Not one of them has had the 'great big lump of engine' infringe on the passenger cabin by very much.

In not one of these incidents was the airframe so distorted that the pilot and passengers could not escape. Two of these incidents were at very high speed and were simply not survivable, deccelerating from 150 kts oddd in the space of a couple of feet does horrible things - but the airframe whilst pretty bent did not compress much and we could easily access the interior.

I would certainly agree that some airfrqames are more likely to have crashes. Either due to the type of flying the airframe does - or foibles in their handling.

Modern airframes do protect the occupants rather better but the nut behind the wheel is a much bigger influence on accident rates and accident types.

[Piper.Classique]

Interesting.....
Take a look at the pawnee for an example of a strong cage around the pilot. I have seen one broken one where the largest single item was the cockpit area. Not exactly a recent type.
As to retrofitting airbags and parachutes, I don't think it would be feasible, any more than retrofitting an airbag in my MGB. If I choose to drive old cars and fly old aircraft surely that is up to me to decide what level of risk I am prepared to accept, an old a/c with superb short field qualities and sodall avionics, which has been flying for longer than I have been on this earth, or state of the art glass. Please let us keep some choice, not one size fits all and the nannies will keep us safe:ugh:

[IO540]

I tent to agree. The State has no business in dictating the attitude to risk of an individual.

The risk to unrelated 3rd party casualties is negligible.

There is a bit of a grey area however when it comes to passengers. What expectation of safety should they have? Tricky one...

As regards midairs, I do think Mode C should be mandatory in all cases unless technically infeasible (no electrical system). Then, the remaining pilots could make a reasonable choice on whether to spend money on some form of TCAS. Currently it is largely a waste of money. Mandatory Mode C would also help ATC in the hundreds of serious CAS busts that occur every year.

[Piper.Classique]

There is a bit of a grey area however when it comes to passengers. What expectation of safety should they have? Tricky one...

Yes, I see your point. I do tell them that the aircraft is 56 years old, and I do give them a safety briefing, but actually I don't think I am putting them at more risk than in a more modern aircraft. If it is that dangerous how did it get to be that old? :D
As for mode C, eliminating the requirement for those a/c without an electrical system would actually remove a surprising number of potential paints. Gliders, which are rather hard to see, rely on battery power for their radios and varios. So do hot air balloons but they are pretty hard to avoid seeing even if they tend not to paint on primary radar.

Actually, I do have an electrical system, but as I have got bugger all to look at inside I tend to keep my head out of the cockpit (and I have a rear view mirror, just as well as everyone keeps overtaking me) ;) Also the passenger gets to help with the lookout, having even less to see inside, once they get bored with the back of my head.

Someone said in another thread that we shouldn't try to solve people problems with widgets. I tend to agree.

[Piper_Driver]

The only real use I can see for a ballistic chute is mid air or structural failure. Both are very rare occurences that probably would compromise the airframe to a point where it wouldn't withstand the forces generated by the chute deployment.


Loss of power over inhospitable terrain at night or in IFR would be another good reason to deploy the chute. Going down in the mountains in poor visibility is almost guaranteed to kill occupants. If I found myself in that situation and had the BRS option I'd go for it.

The chutes work best when the aircraft is in stablized flight at speeds within the normal flight envelope. After a midair or a structural failure stabilized attitude is unlikely, and airspeed might be a problem as well.

[Pace]

Fact is there are I think 23 lives saved using the Cirrus ballistic shute system.
23 people walking around today who wouldnt have been had it not been for the parachute system.

I wonder if the manufacturers of the RAF aircraft which colided and crashed robbing two young kids of their lives had been ahead of Cirrus and fitted such a system years back whether those kids would be alive today?

People usually get killed falling from the Sky or flying into something not in ground accidents.

We might choose to take our own risks but do we have the right to risk others who know no better?

Pace

[Pilot DAR]

I will continue to assert that in most cases, the aircraft cannot be found to be the pivotal fail point in an accident, it is nearly always a human/pilot induced failing. In 5000 hours plus flying over 30 years, it has never even crossed my mind that I would like to exit an aircraft in flight (or give up and plummet in it). This, in the context of having flown several aircraft with major control malfunctions and handling defects. Instinct always had me fight the thing to the ground, and in each case, I landed safely. Sure, one can draw upon an image of an aircraft at altitude, with a failure, and lots of time to think it through, and determine that deploying a chute would be a good idea, but that really is not the reality of general aviation accidents. Most seem to happen with little warning, and /or close to the ground, with little time to react.

I am not trained as a military fighter pilot. I am sure that they have much different training, in which you reach a point where you realize (apparently in micro seconds) that a complete mind shift from “fly” to “flee” is appropriate. I do not challenge this, just comment that such training is definitely outside the norm for civil pilots!

The multi decade old aircraft we fly today, are as safe, or safer than they were when they were new. They have the opportunity for better maintenance. They have the benefit of “tribal knowledge” of type operating experience. And we have somewhat better pilot/aircraft interface (instruments and avionics) all of which should go to make the flying more safe.

On the other side, we have manufacturers who are justifiably running scared of liability, and will make the aviation consumer pay the cost for innovations, which on the surface seem to make the plane more safe, but in reality, give the manufacturer better traction to defend liability claims in court. Then we get amateur built and ultra light aircraft, which are returning us to the simplicity of the “old way” of flying, though with weight limitations which result in difficulty making a truly robust aircraft in some cases.

Engines don’t end up in the laps of occupants at a disproportionate rate, when compared to other injurious circumstances. You’d be surprised how many occupants are injured in aircraft whose cabin structural integrity has not been substantially compromised. I have personally removed a dead friend from his crashed Cessna 150, which had stopped at 200G (according to the coroner). The doors to the cabin still opened, and I was able to enter the cabin. The propeller flange was peeled off the crankshaft, but the engine was still in the mount when we lifted the whole aircraft out.

I can’t accept the notion at face value that 23 people are alive following Cirrus accidents, because of the use of parachutes. The first thought that comes to my skeptical mind is; why does this aircraft type need the chute? Why do it’s pilots need the chute? Why did flight controls fall off the aircraft in flight? Why was the pilot flying over territory so unsuitable for a safe landing? Could any of those 23 people still be alive if the forced landing were skillfully conducted, as opposed to abandoned? Very likely.

Let me think…. Hudson River, New York…. Cirrus pilot (of perhaps modest skill and judgment) flies a probably flyable (and certainly ditchable) aircraft into a building – and fatalities result. Chute did not help, lots of room in the river did not help. Airbus pilot (of apparently highly superior skill and judgment) flies a unpowered and arguably unproven ditching design, to an excellent landing. Parachute not required, suitable landing area appropriately used.

JFK junior spirals in a perfectly serviceable and appropriately equipped aircraft, due to inexperience in the operating environment. Would he have deployed a chute had the aircraft been equipped? Maybe. Would it have helped? Spiraling down at terminal velocity? I doubt it!

I’m not sold on chutes or airbags for GA aircraft. I’m sold on better pilot skill and decision making/risk management training. Yes, chutes and airbags have probably saved lives, but while they were doing that, other lives were also quietly saved, and perhaps accidents entirely averted by well trained pilots who were flying appropriately.

We're making more complex aircraft, and less complex pilots. We're going the wrong way!

Pilot DAR

[Karl Bamforth]

"Fact is there are I think 23 lives saved using the Cirrus ballistic shute system.
23 people walking around today who wouldnt have been had it not been for the parachute system."

I think what you really mean is 23 have survived a Cirrus Ballistic deployment. You will never know in most cases if they would have survived a landing attempt.

I can't say I have followed the Cirrus deployments much but the ones I have seen would normally be handled by a forced landing. Your aircraft may even survive the event, it will not if you deploy the chute.

Someone mentioned the Grob used by the RAF, they have been in sevice for a number of years now averaging something like 30,000 hrs a year. They carry out aerobatics on almost every flight. They take off and land approx every 30 mins which is the most dangerous phase of flight. The Grob 115 aircraft has already demonstrated its safety record. The recent accident is the first fatalities and loss of aircraft. they were low and I doubt that a ballistic chute would have helped.

Some kind of collision avoidance kit may have helped.

[Pilot DAR]

Some kind of collision avoidance kit may have helped.

Proximity sensing airbags - on the outside of the plane! Hey, they'd double for ditching too!

[strake]

This has been a terrible week for light aircraft/private aviation. A report on the death of two young children caused by irresponsible actions and another two children killed for reasons we do not yet know.
However, in both instances, it seems highly unlikely that any form of aircraft safety equipment would have made a difference to the end result.
I notice that some people try to draw similarities to motor racing or the wider automotive industry. There have been incredible advances in these areas but at equally incredible cost. That sort of money is just not available for the relatively small private aviation market.
So, to have a go at answering the original question and at the risk of stating the obvious, the AAIB bulletins have been required reading for me over many years and they seem to suggest the following:

If a light aircraft is flown in a simple A to B way by a current pilot who has received normal PPL training , it is highly unlikely to break up in middair and apart from the odd occassion where maintenance has been called into question, the flight should be of relatively low or acceptable risk.

Once low flying, formation flying, aerobatics, bad weather flying, non currency and so on are introduced, if the pilot is not properly and comprehensively trained for these activities (and current), then the risk increases significantly and the sad tales from the AAIB reflect this. I would suggest it is therefore hard to come to any other conclusion that fault in most cases lies with the pilot and not the airframe.

[Pace]

Some kind of collision avoidance kit may have helped.

Maybe maybe not ? If the aircraft ran in head to head unseen maybe, If they had voluntarely formated on each other and clipped each others wings in a tragic accident no.

Two experienced RAF instructors? That should cover the lack of training scenario.

That then leaves the possibility that it was just a tragic accident.

I put this thread up for discussion and there have been many good comments thanks for that!

One negative with making aircraft appear safer is that as with the Cirrus pilots will fly in conditions where they normally wouldnt because they think that if it all goes wrong I have the shute.

They take larger risks which negate the safety benefits.

The old Cessna 172 has the best safety record but that is an aircraft which has very docile handling, low stall speeds and safe manners.

We have advanced leaps and bounds with the latest generation avionics.

We have terrain awareness, we have night low visibility vision. We have accurate and precise position awareness.

Cirrus have even now introduced a panic button. Loose control press the panic button and the aircraft levels itself.

Whether these advancements will show a long term improvement in accident statistics who knows.

I agree that aircraft dont break its pilots that break them but with all the training in the world we are a diverse bunch and this year has started badly.

Pace

[Rod1]

“Fact is there are I think 23 lives saved using the Cirrus ballistic shute system.”

Very unreliable statistic;

How many would not have taken off if it had not been for the safety blanket of the shute?

How many aircraft have gone through the hedge which would have got airborne if it had not had the extra weight?

How many ran out of fuel re W & B limitations due to the compulsory shute?

How many people have suffered server back injuries which could have been avoided if a conventional ditching had been attempted?

I am not saying this is bad tec, just that it is not that simple to evaluate.

Rod1

[IO540]

Of the Cirrus chute pulls, very few would not have been landable conventionally.

I think only the one who had an epileptic fit.

Somebody else lost control in heavy icing, so maybe that one too, but he may have stalled/spun due to reaching his operating ceiling before that happened.