deceased couple . . .. . ..
 

Believe the recently married parents of two kids were the passengers.
Have not yet seen any report on where they were sitting (back or front).
Reference has been made to weight and balance; could this be relevant ?

AMEand PPL

It could be relevant had the aircraft gone into a flat spin which it didnt recover from or had it been overloaded structurally.

The high speed dive doesnt indicate a flat spin but more a dive or spiral dive which the aircraft didnt recover from.

Pace

As I said before, I more inclined to believe some sort of problem leading to a possible stretching of the glide and stall with subsequent nose down descent into the ground.

Bose

The witness who seemed quite a serious calm sort of guy reported a sharp wing dop followed by an almost vertical dive into the ground. Another witness reported the engine sounding like a high speed drill which for a non pilot was quite an accurate description of the sound of a high rev diving aircraft.

There were no radio calls made in ref to a rough engine or engine failure and subsequent attempted off field landing. Tricky one!

Pace

Which would indicate a stall and probable spin entry. So back to my point about the cause rather than the visible symptom?

"Which would indicate a stall and probable spin entry."

FWIW thats the best sense I can make of the reports so far.

"So back to my point about the cause rather than the visible symptom?"

Cold day, lots of cabin heat, cracked exhaust, carbon monoxide poisoning of the PIC is a leading potential scenario. Wouldn't be the first time. Sadly, won't be the last. It doesn't happen often, but does happen.

Small electronic CO2 detectors with audible alarm are available - can go back in the flight-bag or be left in the aircraft after flight.

Is the CO2 risk worth some outlay on a detector? Like having a liferaft after leaving a ditched aircraft - if it happens to you - there is no question - it is worth it. I am not sure there is a better way of mitigating this risk.

Bose

It could indicate a whole host of possibilities!
Really depends on what height it occurred. A nasty wing drop could have taken the pilot by surprise leading to an over recovery, he could have entered a spiral dive mistaken it for a spin and not recovered from the resulting dive. He may not even have been at the controls ie incapacitation. Something could have broken or seized?

His passeneger in the right seat may have contributed? The list goes on.

The height at which the witnessed episode commenced would be very telling. If indeed it was 100 to 200 feet then a stall stretching the glide could be the reason.
If the witnessed episode commenced much higher then its unlikely.

The shear destruction of the airframe into unrecognisable fragments would indicate a very high speed impact from altitude as would the high speed drill sound of the engine/prop but like you I am only guessing.

Lets hope the AAIB manage to piece together enough from this tragic accident to get a likely cause.

Pace

The 415kv lines that the aircraft seemed to have hit could have been a likely contributor to the scale of devastation.

Sometimes the simplest scenario provides the simplest answer. Looking at the history of accidents in this type their is a recurring theme that seems to come to my mind at least.

Reading the comments about the pilot it strikes me that he was a safe and conscientious aviator who would not have been show boating low level. So looking at other reasons for them to end up so low over a railway track leaves me with a mechanical failure that the pilot was doing his best to salvage.

My gut feeling is a possible power problem, attempt at a forced landing, poor choices to put down, an attempt at stretching the glide to clear the railway tracks and subsequent stall spin.

And all witnesses report a high-revving engine ??

My wife thinks the engine on my cessna sounds high revving at idle. If the engine was running it could sound 'high revving' to the untrained ear. This would not preclude there being a power problem that prevented the aircraft maintaining height.

I have an open mind to any other possibility but as I said quite often the simplest answers are usually not far from the reality.

It is interesting as an Instructor to see how people struggle with flying accurate PFL's during the 2 year review flight. Just because it is a skill that is rarely practised by most. It is very easy to get on the back of the curve during practice so think about it during a real emergency?

My concern too was the high revving engine a stall low level into power cables and you would expect a lot of large pieces of wreckage rather than the powder remains. The cables were destroyed which also indicates a high speed collision with them too.

The high speed electric drill sound reported by a non pilot did it for me because that is exactly what a high rev high speed dive sounds like.

We are all guessing so lets hope the AAIB have more.

Pace

Pace, I would expect quite the opposite. Hitting 415Kv lines would have caused an explosion and intense fire in my experience. When I worked for railtrack we had to do a 'person' course that would allow us trackside and one of the videos showed a van bringing down the high voltage cables. It was flash incinerated in seconds.

The TV images remind me of this video acclerated by the Avgas I suspect.

i don't know the location where the crash happened.

If he was higher up when the problems began, surely he would have made a call, as pushing that talk button does not preclude any simultaneous action in the cockpit, I think it would be second nature to do so.

In that case the question is natural, to ask if he was on an approach to a field.

Carbon Monoxide poisoning could explain descending (at increasing speed) without a call and perhaps the sharp wingdrop at the first contact with the powerlines.

The alternative of flying low (without being on an approach) and slow and stalling when trying to avoid the powerlines would be awful indeed

Van Horck

As far as we know there was no call made of any problems. The Pilot was in his mid sixties. For all we know it could have been pilot incapacitation with the passenger not even knowing how to use a radio or how to fly an aircraft.
It is all guesswork and as such important to keep an open mind.

Pace

Or it could just have been that he was non radio(by non radio I mean not talking to anyone) and the incident arose so quickly that his priority was to aviate before communicate.

I hardly turned my radio on in the last week with no one to speak to.

Gents sadly they hit the 25,000V West Coast main line power cables & catenary. From memory these can take something in the region of up to 1000 amps before disconnecting, so apart from the energy of the crash you may be looking at something like 25MW (million watts) of electrical power dissapation as well.

On a short circuit, the circuit breaker up the line would have tripped in a small fraction of a second.

At a descent rate anything like that reported by the witnesses, the time between slicing the power cables and hitting the ground would be so short that the power cables would not have made any significant difference to their trajectory, which was apparently more or less straight down.

For my own benefit - Does Pilot Incapacitation mean heart-attack?

IO, it does not work like that on the railway power grid or the national power grid for that matter.

I have the exact details from the course somewhere but it is something to do with the way power is drawn by the engines that would cause a CB to trip out all the time. Even when severed it is possible for the lines to remain live. The lines are also capable of generating their own electricity from static accumulation.

It can mean a heart attack but could mean any condition where the pilot was unable to fly the aircraft.

Pace

a very wide term . . . . . . .
 

Yes, it certainly could do, but, as Pace says, it could also mean anything whereby normal control of the aeroplane by the pilot is reduced or prevented. The list could be almost endless . . . . . . .

Heart attack, stroke, epileptic fit, poisoning ( CO, food);
even anything which, due to severe pain, is totally distracting, eg renal colic.

And we all remember the pilot who was struck blind late last year . . . . .:sad:

I am tending to lean towards incapacitation of either the pilot or airframe /controls bar the pilot doing something stupid aerobatic wise.

But doing something stupid aerobatic wise could lead to airframe /control problems.

The pilot was fairly old mid sixties so unlikely to be a tearaway hot rod although you do get some.

He was experienced in an aircraft he had flown for years. That would mean it fitted him like a glove. He would know every twitch or burp it made.

The PA28 140 had the old slab wing which was the most stall resistant and docile wing used even today on the seneca twins.

I dont think there are any indications to show an engine failure, glide and stall spin.
unlikely to a pilot who knew the aircraft so well.

No radio calls would indicate something abrupt in either the pilot or the airframe. The vertically down and destruction in the accident site to me means from altitude.

Incapacitation / airframe control problems / possible semi aerobatics? which is quite a wide spectrum of possibilities. But hey my instincts might be totally wrong.

Pace

I have twice in (newer) PA 28s discovered excessive movement in the "stablator" bearing. When pointed out to the engineers the AC was grounded immediately.
Is it possible that it could fail completely? Does the 140 have the long counterbalance, which I believe was subject to an AD?
DO

i am aware of a PA28 who's ailerons failed (plane landed safely after lining up with rudder only), due to manufacturing error (years after manufacturing). Structural failure of the elevators (trim system?) or similar is not common but not impossible

correction . . . . . .
 

Excuse me, mid-sixties is NOT old ! ! Actually he was only 59.

Sorry, back to the serious stuff.

Mid sixties is young(ish)
 

I knew a remarkable lady who rode to hounds into her nineties and drove the horsebox.Mind you ,you wouldn't want to meet her coming the other way in the horsebox.
Played tennis into her eighties until she injured her arm.
She lived until 104 and at her 100th consumed enough bubbly to gently fall over ,caught gracefully by a guest.
She had been out in Africa before the war and knew all the people in Happy Valley,when I asked her what they were like she said
"An absolute waste of time ,my dear"
They don't make too many like that!

A lady friend lives down the lane,90 years old,had her first flying lesson a couple of months ago.
Lady friend of my wife ,in case you had other thoughts.

Sorry thread wander,happens when you get old.;);)

PPLandAME and Lister Noble

My apologies for incorrect use of old :) Mature Pilot rather than 20 year old Hot Rods who would beat up any bit of railway line . And yes I do know a few "Mature" pilots who pull a few loops and barrel rolls ;) I hope he wasnt one of them.

Pace

dont overfil

The stabilator control system is a valid topic, in my opinion.

One of the important pre-flight checks on the -140 is to look down inside the fuselage from the rear of the stabilator to ensure the control jack and cable are in working order.

I understand that the cable can come adrift from the screw jack, but I have never heard of this in practice. Maybe our engineering friends can shed some light on this issue?

With the aircraft being over 40 years old and the CofA within a couple of months of expiring, I wonder if this was a consideration? It is the only structural/control failure I can think of which is a known possibility and for which one always checks.

The accident is certainly baffling at the moment, as so many people have already pointed out.

KR

FOK

Not speculation,but....
 

I was thinking along these lines a couple of days ago but did not post.
I do the pre-flight as best I can on the L4 and take my time ,a very simple craft although there are hidden cables for all the major controls.
We have the annual and 25 and 50 hr checks but some of these sytems will not be inspected for a whole year.
Not speculating on this accident,but it does make one think about what goes unckecked.
Lister

The thing is that, with a good pilot, the total loss of any one of

- aileron control

- elevator control

- elevator free movement

- elevator trim

- rudder control

is not a problem unless it happens in the middle of an aggressive maneuver (an unusual attitude, basically). If it happens in more or less level flight, the plane isn't going to plummet. You still have control, due to secondary control surface effects (rudder for roll/turn, elev. trim for pitch, etc).

If the elevator falls off, the plane will plummet allright but the witnesses did not suggest this happened.

There have been (rare) light jet accidents where an engine disintegration shredded control cables to the tail, resulting in a loss of control. Could this have been the Biggin Hill Citation one, recently? But that isn't likely in this case - the engine is up front.

FWIW

I have not flown a PA-140 in quite a while, but did my initial training in -161/-181s. One of the things we always checked during preflight was the integrity of the bolts that limit the stabilator travel. If they fail, you can totally overcontrol the a/c. However, you would of course only be in danger of doing so by moving the control surface (stabilator) to its limits.

This is really a weird one. My guess is human factors of one kind or another....

I'm puzzled, perhaps you can help out. How do you know there was no radio call? Who was the pilot speaking to on the ground?

Spitoon

Read it in one of the numerous tabloid press articles so maybe false but that is all we have to go on at present as well as the witness statements.

If there was radio communication chances are that whatever the problem would have been broadcast or picked up from one source or another. ie it would have already leaked out to the media.

"Mayday Mayday Mayday xyz has a rough engine or Pilot unwell request vectors to nearest airfield".

The fact that no one is the wiser would indicate that the press were correct in their statement and that whatever happened was abrupt.

Flying VFR they may not have been talking to anyone or may have been on an FIS with a ground station who probably were not that interested in them anyway. A Mayday call would have drawn attention but unless someone knows otherwise no such call was forthcoming.

Pace

This has got to be one of the most ridiculous cases of amateur accident investigation ever seen on the internet.

'Elevators not seen coming off a PA28, stabilator control jacks and cables visible in the rear fuselage from the back on a pre-flight, no radio call was made because it said so in tabloid newspapers, over control the aircraft because of a missing limit stop, aircraft was nearly due an Annual etc etc etc'.

Sounds like some of you should progress beyond the I-Spy book of aircraft and then you might know a little bit more about what you are putting into print. Hope the media don't believe you and you wonder why the press get things wrong!!

Give me strength....!

Pace, No offence, but I am sorry I think you are giving the pilot a level of skill in dealing with an in-flight emergency that I have rarely seen in GA. When practising PFL's with students 99.9% of them do not even think of a radio call let alone have the mindset to actually tune the thing to an appropriate frequency and make a call all at the same time as choosing a field, getting best glide and going through drills. Not to mention the fact that this was the middle of the holidays with most places shut. I hardly even turned my radio on during the break let alone talked to anyone. I am more likely to give credit that the guy was attempting to aviate following a failure and just ran out of options.

As smarthawke has said this really is getting beyond the realms of belief.

And as I have said a couple of time before, the simplest explanation is usually the correct one.

Bose

We none of us know what happened to cause that tragic accident it is all speculation.

SmartHawke

This is a pilot forum. IMO it is healthy for pilots to discuss and disect the possibilities of why an accident occurred. It can happen to any of us here.

The more we discuss the more aware we become of not only the accident in question but of other potential threats to our safety.

IMO it is only when these awful things happen that we take stock and realise our own vulnerability and hence learn and no we are not the media but a pilot forum.

Pace

I am with you Pace.

Yes the most obvious reason is the likely one, but not always.

Either way, us all wrecking our brains to think of potential scenario's is a good thing for all of us. And sharing them helps our brain working.

Thinking of scenario's without hurting the ones left behind unduly (respect) is what this forum is about. The ever recurring discussion as to post or not post is just a side annoyance coming from new members and a few die-hards

OK smarthawke. What was the AD on the counterweight about?
DO.

All we know about this accident is the aircraft was destroyed in a high speed impact.

Almost every scenario you can dream up is a possibility, and about the only scenario that can probably be eliminated is the accident was not weather related.

A discussion about what you would do if an aileron failed would be informative and worthwhile. Flag the thread as such and it will attract attention.

Second guessing hypothetical accident scenarios and half debating each is probably the best way of disconnecting from most readers on this forum.

Sorry, but you have almost nothing to go on, and this has just become another utterly pointless “what if” debate.

However, don’t let me stop you, debate on, that is what this forum is about, in the same way that I simply wanted to explain why I didn’t join in.

.. .. .. and to answer the last post, if you want to excercise your brains (which I would agree is probably a good thing) then as I suggested earlier go start dedicated threads along the lines of "the thread on X-XXXX got me thinking, what would you do if .. .. .. ). :)

Will we ever know?
 

I have no problem with all the speculation being expounded here but with what appears to be the total destruction of the aircraft compounded by the subsequent fire,is it possible that the AAIB would be able to provide a definite cause with so little to go on?

The AAIB appear to be an extremely thorough organisation but I imagine there is very little physical evidence for them to analyse/test.Maybe this will remain a mystery forever.

MM