Same Old Story. Maintenance release not found in fatal accident.

[A37575]

ATSB have just released its report on a Dromadeer fatal accident in Queensland. Part of the report says this:

The most recent documented maintenance task carried out on the aircraft was a scheduled annual inspection and maintenance release issue that was completed on 29 June 2011. The maintenance release was valid until 29 June 2012 or 5,996.7 hours TTIS, whichever occurred first.
The investigation examined the aircraft’s maintenance documentation and no deficiencies were identified that would affect normal flight. Since the maintenance release was not recovered, the investigation was unable to determine if there were any recorded outstanding defects.

In the past years there have been dozens of ATSB/BASIS reports which stated either the maintenance release was destroyed in the crash fire or could not be found in the wreckage. Since the maintenance release and its entries of current and rectified defects is clearly a vital high priority part of the investigation process, it seems an illogical legal requirement to carry the original document in the aircraft on every single flight. The chances of the evidence in the maintenance release being destroyed in the accident is high - witness the comment by ATSB in their reports.

So why on earth does CASA persist with the ridiculous requirement to carry the original document in the aircraft? As far as I recall, in high capacity types, a copy of the current page of the maintenance document and signed by the captain, is left at each stage; along with a passenger and freight manifest. If the aircraft is destroyed in an accident it is easy to retrieve the last copy from the last port of call.

The subject has been discussed in Pprune over the years and in fact this writer wrote to CASA 15 years ago suggesting a review of the requirement. Whoever in CASA at the time wrote the reply, was not only not in the slightest bit interested, but said that it didn't matter if the maintenance release was destroyed since the original was kept by the maintenance organisation. He was obviously confused with the fact that the last maintenance release is filed away at the maintenance organisation - not the current one.

I am surprised (or maybe not) that ATSB or CASA are not particularly concerned if the current maintenance release carried in an aircraft is unavailable to these organisations because of its destruction in post accident fire.

Are they implying that any defects endorsed in the destroyed maintenance release willl probably have no bearing on the cause of the accident? Ostriches hiding their heads in the sand come to mind...

[Creampuff]

So where would you suggest the MR be left?

[kalavo]

Plenty of companies where the original MR is in the aircraft and a carbon copy is left behind (Sector/Trip record per page)

Of course CASA would have to replace their wax paper with a similar system for it to expand to Class B aircraft.

[A37575]

So where would you suggest the MR be left?

Apologies - I should have made that more clear. Carry the MR as per current rules (like pax and cargo manifest) but at each point of departure leave a copy of the relevant defects and times flown pages with an appropriate agent - refueller, local flying school, or like a flight note with anyone in the vicinity. Cost nothing but could be of immense value in case of accident that destroys original MR. Same with flying schools.

[Clearedtoreenter]

A37575 makes a good point. The MR is a way of letting the next pilot know what went wrong or any other issues but does anywhere else in the world carry the ONLY record of recent defects and/or corrective maintenance needed that could affect the safety of further flight and potentially the only sign-off, actually in the plane? (That's if it gets filled out with this information at all of course...)

Yup just what every GA company needs, everyone else knowing who their clients are, how many hours are left on their MR, what defects they are flying with, how long they have to go till the next 100hrly.

Yes, so up to up to date maintenance info should be considered 'commercial in confidence'? Some pax, investigators and others (and/or their lawyers :) )might actually be quite interested in that. Much better it gets destroyed in the crash then eh?

Let's face it, with stuff like Flightaware, everyone knows in real time exactly what we are doing, where and how we're going. So what's the problem in letting those who have a legitimate nterest know we're doing the right thing with maintenance? Or in GA.culture, might there be some things we'd rather some folks did not know?

[Hasselhof]

'commercial in confidence'?

(passengers and/or their lawyers)might actually be quite interested in that

Which is exactly why it is in commercial in confidence.

[Aussie Bob]

But of course this begs the question: How many defects, recorded by a pilot on a mantenance release, have led to a fatal accident. In GA I would guess not many.

Please don't tell me you want GA pilots to ensure that a copies of the mantenance release are to be left scattered across the countryside and this will be part of my next audit. I can see it now, "please wait here ladies and gentleman, the refuellers photocopier is not working".

By the way your example is a single seat ag aircraft.

[Creampuff]

… at each point of departure leave a copy of the relevant defects and times flown pages with an appropriate agent - refueller, local flying school, or like a flight note with anyone in the vicinity.You obviously don’t fly into many of the ghost towns that pass for GA aerodromes on the weekend in Australia these days.

But let’s assume we find Fred in the Flying Club at the aerodrome we refueled at. We give Fred a copy of our MR. Is Fred obliged to keep it and, if so, for how long? We’re on a round Australia tour, by the way.

Hang on a sec: Fred’s going flying! He gives us a copy of his MR. Now what do we do?

A week and 6 stopovers after passing the copy to Fred, I crash 1,000nm away. Is Fred’s copy important and, if yes, how does the ATSB know about and find Fred?

[Kharon]

CP - Hang on a sec: Fred’s going flying! He gives us a copy of his MR. Now what do we do?:D

Reg 362436.
1) The pilot of crashing aircraft must accurately complete the defect section of the Maintenance Release at least 1.76 Kms from the intended crash site.

2) The MR must be inserted into an approved empty boot polish tin and ejected no less than 500 meters from the intended point of impact.
a) Failure to do so constitutes a breach of the Act and is punishable by 2 years in prison after such hospital treatment as deemed by the DAME is complete.
b) Failure to properly fold the MR is a strict liability offence. 25,000 penalty points.

HAGW :D :D

[Ixixly]

Just a thought, and feel free to shoot me down.

But as pointed out leaving a copy everywhere isn't very practical...so why wouldn't (This is taking a commercial organisation) you leave the original back at Base where its secure and people can't find out what it says but is accessible by CASA or the ATSB in the event its required?

Lets say something becomes defective en-route and you needed that noted on the MR, well call back to the office and let them know, chances are you're going to have to call them anyway to get it fixed.

Leaving the original back at base once its been signed off in the morning and then amending it if required seems to make a lot more sense!!

[industry insider]

Why not go digital and input entries into an iPad where the information is stored in the cloud? It might even help people get their maths correct. The iPad could double as an EFB, manuals, charts etc.

[Aussie Bob]

Why not just keep going the way we are going.

A scenic flight mob I worked for recently always kept the MR's in the office. They even applied for a dispensation to do same but the request was never answered. Funny enough, come ramp check and audit times the CASA inspectors were always happy with the arrangement.

[eocvictim]

All of these suggestions are increasing in expense and complexity. The most cost effective, practical and reliable method is a simple fax or photocopy or digital image of the MR once daily or when ever amended, where practical.

The reality is aircraft will end up away from base or be shuffled around the country side from base to base for different missions, making it impossible to leave the MR anywhere but in the aircraft (for the sake of the next pilot to be able to review the most current copy). There are exceptions to this where they could be left with a 24 hour operations department that collects and compares all maintenance information. Even in this instance keeping the MR in the aircraft is still more practical because the operations department still has (relatively) up to date information.

The idea of copying it per sector is just poorly thought out. Some crews will do as many as 10 sectors a day with aircraft doing up to 15 in a 24 hour period, spread that across 10-15 aircraft and you're talking up to 220 copies of MR's a day!

Even if you were to pursue a more accurate and up to date approach, by mandating a CC of the MR at every intermediate destination, would you really resolve the issue? Most minor defects are not detected until postflight or in the next preflight inspection and major defects that are detected are usually reported immediately, negating the need to leave a CC behind. In the cases where the known defects aren't reported immediately you will more than likely find they wouldn't have been entered in the MR at that point regardless (if at all), which is of course a cultural issue and arguably the real problem with regards to maintenance and defect reporting and recording.

If the operators who are abiding by the regulations (not speaking in terms of the above or other private or very small operators who may not have considered the consequences) are making the effort to record current defect items alternatively to the MR, then mandating more than what others have already implemented, at little or no cost, just adds to the bureaucratic jumble. A CAAP on possible internal monitorial means would be more than sufficient for those that have not considered the options and those that don't take it's advice wouldn't have appropriate records to make a mandate justifiable anyway.

[currawong]

Part 137.120 refers.

No requirement for the operation mentioned to carry the MR on board.

[Creampuff]

Only if the aircraft was not operating more than one hour’s flying time from the operator’s principal operating base or substitute base.

[currawong]

Correct.

Most however have a variation in place in the ops manual that exempts the requirement.

[Creampuff]

The ops manual provision (137.120(5)) does not appear to permit the non-carriage of entire documents, but rather only ‘a specified part of’ e.g. the ‘aeroplane’s flight and maintenance records’.

[currawong]

Also known as a Maintenance Release.

[Engineer_aus]

All I can say is clearly you have no idea how the system is run, or any experience in the industry.

[blackhand]

All I can say is clearly you have no idea how the system is run, or any experience in the industry.
Only an Engineer could put it so succinctly.:D

[Old Akro]

Its been a long time since I studied Aerodynamics. We had an ex NASA lecturer and he did a pretty thorough job. But I cannot recollect any factors relating to the properties of paper in Bernoulli's theorem.

There are three things wrong with the premise of the question:
1. we need simpler systems not more complex ones. I think there's a fair argument that we have already crossed the line on Dr James Reason's graph indicating that the amount of process we have is detrimental to safety and not conducive.
2. GA pilots will run a mile already from recording things on the MR. This would make it worse. Want a metric? Have a look at the rate of doctors reporting other doctors poor practices since it became a mandatory government instrument rather than a peer to peer process.
3. If there is a real issue with the aeroplane it will be found in the crash investigation (which will include interviews with the signing LAME and other pilots who fly the aeroplane). There is a big danger that squawks on the MR will just be another bureaucratic mechanism to buck pass to the pilot.

[Creampuff]

I see your point, currawong.

If that was aimed at me, Engineer_aus, you are correct. I'm merely an acne-stipled wheelchair-bound geek from hicksville USA. :ok:

[Centaurus]

2. GA pilots will run a mile already from recording things on the MR

Says a lot for the integrity of those concerned especially for the poor bunny who takes the aircraft over from them on the next trip..

[Hasherucf]

2. GA pilots will run a mile already from recording things on the MR

I suspect this practice is from aeroclub or training schools talk. Ive worked in several large GA companies and had to chase pilots (daily) to enter defects on MR's . Some Ive even corrected defects and they have entered it on the MR days later. :ugh:

And for christ sake someone teach pilots addition in flight schools. Surely they can add up hours ???

[Tee Emm]

Quote:
2. GA pilots will run a mile already from recording things on the MR
I suspect this practice is from aeroclub or training schools talk.

It has always been thus in Australian general aviation. A few years back a grade 3 instructor asked me to look at apparent jammed circuit breakers in a Piper Archer at Essendon. Several were immoveable and this was confirmed by an LAME. The G3 was frightened to write up the defect in the maintenance release lest the aircraft owner refuse to let him fly the aircraft which was on line with a small flying school (now long since defunct). No aircraft to instruct on meant no money for food for the G3. So I wrote in the defects for him.

The owner protested the defect was trivial and threatened to send me the bill for an LAME to check the defects, if in fact there was nothing wrong with the circuit breakers. I sent his letter to CASA adding it was this sort of behaviour by some owners that was typically responsible for defects not being endorsed in maintenance releases.

Technical investigation revealed that the majority of the circuit breakers in the Archer were unserviceable and would not have actuated in event of electrical overload fault. Nothing more was heard from the businessman owner who had a reputation in the flying school game of being short fused..:ok:

On another occasion a flying school cross-hired a Seneca from a well known maintenance organisation at Moorabbin. On its first flight at the flying school, it was noticed that the prop feathering action on one engine was markedly slow compared with the other engine. The pilot endorsed the maintenance release. The LAME owner got upset and directed to the flying school that the instructor was hereby banned from using that aircraft.

The CFI of the flying school was heartily pissed off at the instructor for writing up the defect as the aircraft had lots of bookings coming up. Undeterred, the instructor contacted CASA, who investigated. The investigation revealed a broken feathering spring which had been like that for several months - including scheduled inspections. In those months other pilots had chosen not to write up the defect. The ramifications of that are obvious if an engine failure had occurred and the prop was slow to feather. The owner then had the hide to blame the instructor for costing him several thousands of dollars for cost of repairs and downtime.

Is it any wonder why general aviation pilots continue to avoid writing up defects in the maintenance release? They have learned from the experience of their predecessors and would rather risk the attention of CASA than risk being given the DCM (Don't come back Monday) by aircraft owners. Having said that, the examples above were from years ago, so hopefully things should have changed for the better by now.

[Charlie Foxtrot India]

Many moons ago when I was instructing in the Channel Islands we had a "tech log" for each aircraft which was kept with ops.

At the beginning of each flight you checked the tech log for defects. At the end of each flight, you entered the name of the pilot, the hours flown and any defects. If there were none, you wrote "nil defects". If there was one, say a u/s beacon that didn't ground the aircraft and was being carried forward, you wrote "nil further". If there was a defect that grounded the aircraft, you wrote a/c unserviceable due (defect) and ops/engineering would take it from there, just as they would following a telephone call if we were stranded away from base.

Every day, or sooner if it was urgent, ops and the chief engineer would study the tech logs and schedule maintenance. The CAA would review the tech logs in the event of an incident.

How hard is that??

[Creampuff]

I think that part of the complexity in this discussion is that the opening post assumed that there’s a ‘one-sized-fits-all’ solution to a problem that s/he perceives arises when an MR is destroyed.

The solution described by CFI worked for that specific operation and was evidently acceptable to the regulator. The characteristics of the operation described by CFI appear to include that there was only one operator and continuous operations of the same kind/s by that operator’s crew. That meant the maintenance records could be kept up to date, centrally, and the correct decision made as to whether a defect ‘grounded’ the aircraft.

As currawong pointed out, there are already provisions allowing the MR not to be carried, if the operation satisfies specified conditions.

But you only have to change one or more of the characteristics in the operation described by CFI, and the solution doesn’t work. That’s why the provisions allowing the MR not to be carried only apply in specified circumstances.

For example, a defect may not ‘ground’ an aircraft for one kind of operation, but will ground it for another. When an aircraft can be operated by different people in different kinds of operations, ‘away base’ for extended periods, there seems to be no practicable way of maintaining up to date maintenance records for the aircraft, other than carrying the MR in the aircraft.

For those Aussies inclined not to enter things on MRs, best to read CAR 50 again. For those Aussies inclined to browbeat people into breaching the law by pressuring them not to comply with CAR 50, do you really think there’s no law about that as well?

[Charlie Foxtrot India]

Not just acceptable but REQUIRED by the regulator, in this case the UK CAA. This was an operation with several aircraft and employees flying all over Europe.

Have flown in a few different countries and seen similar systems, the first time I ever came across a maintenance document being carried on board was here in Aus and I though the instructor was joking when he said the original had to be carried in the aircraft! My first thought being, if there is an accident presumably this document would be destroyed so what use is that??

[Checkboard]

The information on the MR at issue is copied in the maintenance records kept by the organisation doing the maintenance. The endorsement on the MR is to inform other pilots of the maintenance state of the aircraft.

The information written on the MR doesn't magically make it's way to the hangar, so you still have to contact the maintenance organisation handling the aircraft to inform them of the defect - and when they rectify that, the work is recorded.

I see zero benefit for keeping the MR off the aircraft. I see zero problem with the MR being destroyed in a crash - all of the records of any importance are available elsewhere.

[Creampuff]

In fairness to the OP, Checkboard, let me posit a fairly common GA scenario.

Aircraft comes out of an annual with a shiny, clean MR.

At around 50 hours TIS after the issue of that MR, the owner of the aircraft decides an oil change, including an oil filter change, is required. This maintenance is permissible by Sched 8 of the regs).

The owner does the right thing, and enters this oil and oil filter change in the MR.

Now the (fortunately not-so-common) accident scenario: The aircraft suffers an engine failure and unfortunately the aircraft suffers substantial damage in the accident. The MR is destroyed.

The questions whether the engine had been the subject of an oil and filter change and, if so, by whom and when, become pretty important.

The records of the maintenance org which issued the shiny, clean MR, indicate that the it (the maint org) did the last oil and filter change.

[TURIN]

Airlines don't leave a copy of their MR (equivalent) at each port, a copy is collected at the end of each day, but not every landing.

Not correct.

After each flight the Tech Log is endorsed by the Captain along with any defects. If no faults then "Nil Defects" is entered in the log.
The Captain accepting the a/c (doesn't matter if he/she is the same or a new one) signs the log after reviewing all maintenance.

A copy is removed from the log and kept at that station for two years (EASA regulation I think).

This happens after every flight.


I have learned something today. I assumed GA a/c would have a similar system.

[Checkboard]

Creampuff, how often would a scenario similar to that occur, against the cost time and effort for leaving MR copies scattered all over creation?

... and how many aircraft in the GA fleet have oil changes done by other than a LAME ;) (A couple, I know - but very few in percentage terms.)

[Creampuff]

how often would a scenario similar to that occur, against the cost time and effort for leaving MR copies scattered all over creation?Very rarely, and I agree completely. ... and how many aircraft in the GA fleet have oil changes done by other than a LAMEI have no hard data, but my guess is that quite a few private owners would do their own around the 50 hour mark between annuals. I frequently put my life in the hands of a private pilot who does his own oil/oil filter changes. :eek:

[Clearedtoreenter]

Have flown in a few different countries and seen similar systems, the first time I ever came across a maintenance document being carried on board was here in Aus and I though the instructor was joking when he said the original had to be carried in the aircraft!

+1 to that.

Aren't we seeing some wonderful illustrations of Aussie GA culture here?

OK OK, 'DCM' ;)

[Charlie Foxtrot India]

The need to reinvent the wheel, yes.

eg replacing Pilot Operating Handbooks with those Australian Flight Manuals...no wonder there are so many myths and legends and "my instructor told me I should always/never etc etc" about how to operate aircraft even now years after POHs were recognised as the vital document they were! And CASA still have those wierd boxy "cessna" charts in the exams, instead of the actual tables in the POH.

When I do an AFR I ask the pilot what he is actually signing when they put thier signature in part 3 of the MR. The answer is all too often "My instructor told me :ugh: that it means I'm the pilot in command" or "I have to sign it again because the last guy who signed it today was a PPL" or some such other nonsense.

Most of them have never ever been shown CAR 42ZE CASA Sched 5, or even read the explanatory red writing on the MR. :ugh:

[Creampuff]

It’s sad that many licence holders no longer meet the standard.

It’s also sad to see what decades of reform have produced.

Here’s what Sched 5 says today about Daily Inspections (minus the additional items for Ag aircraft) Schedule 5 CASA maintenance schedule

(subregulation 2 (1), definition of CASA maintenance schedule)

Part 1 Daily inspection

1.1 An inspection (in this Part called a daily inspection) must be carried out on the aircraft before the aircraft’s first flight on each day on which the aircraft is flown.

1.2 A daily inspection must consist of the making of such of the checks set out in the table at the end of this Part as are applicable to the aircraft.

Table of checks included in a daily inspection

Section 1 General

(1) Check that the ignition switches are off, the mixture control is lean or cut off, the throttle is closed and the fuel selector is on.

(2) Check that the propeller blades are free from cracks, bends and detrimental nicks, that the propeller spinner is secure and free from cracks, that there is no evidence of oil or grease leakage from the propeller hub or actuating cylinder and that the propeller hub, where visible, has no evidence of any defect which would prevent safe operation.

(3) Check that the induction system and all cooling air inlets are free from obstruction.

(4) Check that the engine, where visible, has no fuel or oil leaks and that the exhaust system is secure and free from cracks.

(5) Check that the oil quantity is within the limits specified by the manufacturer for safe operation and that the oil filler cap, dipstick and inspection panels are secure.

(6) Check that the engine cowlings and cowl flaps are secure.

(7) Check that the landing gear tyres are free from cuts or other damage, have no plies exposed and, by visual inspection, are adequately inflated.

(8) Check that the landing gear oleo extensions are within normal static limits and that the landing gear doors are secure.

(9) Check that the wing and fuselage surfaces are free from damage and that the inspection panels, flight control surfaces and flight control devices are secure.

(10) Check that the interplane and centre section struts are free from damage and that the bracing wires are of the correct tension.

(11) Check that the pitot heads and static ports are free from obstruction and that the pitot cover is removed or is free to operate.

(12) Check that the fuel tank filler caps, chains, vents and associated access panels are secure and free from damage.

(13) Check that the empennage surfaces are free from damage and that the control surfaces control cables and control rods, where visible, are secure.

(14) Check that the canard surfaces are free from damage and that the control surfaces, control cables and control rods, where visible, are secure.

(15) Check that the flight controls, the trim systems and the high lift devices operable from the ground have full and free movement in the correct sense.

(16) Check that the radios and antennae are secure and that where visible, radio units and interwiring are secure.

(17) Check that the drain holes are free from obstruction.

(18) Check that there is no snow, frost or ice on the wings, tail surfaces, canards, propeller or windscreen.

(19) Check that each tank sump and fuel filter is free from water and foreign matter by draining a suitable quantity of fuel into a clean transparent container.

(20) Check that the windscreen is clean and free from damage.

(21) Check that the instruments are free from damage, legible and secure.

(22) Check that the seat belts, buckles and inertia reels are free from damage, secure and functioning correctly. Here’s what Schedule 5 said around 20 years ago:SCHEDULE 5

Subregulation 2(1) (definition of “CAA maintenance schedule”)

CAA MAINTENANCE SCHEDULE

Part 1 Daily inspection

1.1 An inspection (in this Part called a “daily inspection” ) must be carried out on the aircraft before the aircraft’s first flight on each day on which the aircraft is flown.

1.2 A daily inspection must consist of the making of such of the checks set out in the table at the end of this Part as are applicable to the aircraft.

TABLE OF CHECKS INCLUDED IN A DAILY INSPECTION

Section 1 - General

(1) Check that the ignition switches are off, the mixture control is lean or cut off, the throttle is closed and the fuel selector is on.

(2) Check that the propeller blades are free from cracks, bends and detrimental nicks, that the propeller spinner is secure and free from cracks, that there is no evidence of oil or grease leakage from the propeller hub or actuating cylinder and that the propeller hub, where visible, has no evidence of any defect which would prevent safe operation.

(3) Check that the induction system and all cooling air inlets are free from obstruction.

(4) Check that the engine, where visible, has no fuel or oil leaks and that the exhaust system is secure and free from cracks.

(5) Check that the oil quantity is within the limits specified by the manufacturer for safe operation and that the oil filler cap, dipstick and inspection panels are secure.

(6) Check that the engine cowlings and cowl flaps are secure.

(7) Check that the landing gear tyres are free from cuts or other damage, have no plies exposed and, by visual inspection, are adequately inflated.

(8) Check that the landing gear oleo extensions are within normal static limits and that the landing gear doors are secure.

(9) Check that the wing and fuselage surfaces are free from damage and that the inspection panels, flight control surfaces and flight control devices are secure.

(10) Check that the interplane and centre section struts are free from damage and that the bracing wires are of the correct tension.

(11) Check that the pitot heads and static ports are free from obstruction and that the pitot cover is removed or is free to operate.

(12) Check that the fuel tank filler caps, chains, vents and associated access panels are secure and free from damage.

(13) Check that the empennage surfaces are free from damage and that the control surfaces control cables and control rods, where visible, are secure.

(14) Check that the canard surfaces are free from damage and that the control surfaces, control cables and control rods, where visible, are secure.

(15) Check that the flight controls, the trim systems and the high lift devices operable from the ground have full and free movement in the correct sense.

(16) Check that the radios and antennae are secure and that where visible, radio units and interwiring are secure.

(17) Check that the drain holes are free from obstruction.

(18) Check that there is no snow, frost or ice on the wings, tail surfaces, canards, propeller or windscreen.

(19) Check that each tank sump and fuel filter is free from water and foreign matter by draining a suitable quantity of fuel into a clean transparent container.

(20) Check that the windscreen is clean and free from damage.

(21) Check that the instruments are free from damage, legible and secure.

(22) Check that the seat belts, buckles and inertia reels are free from damage, secure and functioning correctly.Experienced readers will have noted the changes to the use of italics, capitalisation, bolding and quotation marks in the intervening decades, which changes, though ostensibly subtle, have undoubtedly improved pilots’ understanding of and compliance with the Daily Inspection requirements.

[Old Akro]

My point which I have failed to convey properly, is that the MR is a legal document pertaining to the legally required MEL and maintenance issues. Proper maintenance is a lot lot more than that. Squawks and performance degradation should be tracked prior to failure. That's the heart of planned maintenance. Most owners I know are discussing and tracking some issues with their LAME's 2 or 3 100 hourly inspections into the future.

But, I think doing this on the CASA legal document is simply asking for trouble. Every owner should have some issues that are being watched or tracked and managed in advance of them developing to a level that requires a MR entry. I think this is what the airlines do with Tech Logs. I can see nothing but grief doing this on the MR. Fundamentally, CASA are interested in attributing blame, not increasing safety.