Skydiving plane crash Lake Taupo

[Dave Homewood]

I am amazed no video has emerged from the people on the lake shore.

[delticman]

I don't think it was one of the well known beaches on Taupo.

[baz62]

Personally if I was forced to do a water landing but had a parachute option I'd take the chute, plenty have people have died landing aircraft on water. All it takes is a bump to the head to knock you out, 4 or 5 minutes later and your dead.

[lumpy]

Jan 11, 2015 9:26:49 GMT 12 baz62 said:

Personally if I was forced to do a water landing but had a parachute option I'd take the chute, plenty have people have died landing aircraft on water. All it takes is a bump to the head to knock you out, 4 or 5 minutes later and your dead.

Agreed , but would it have been a water landing ? If the pilot made it to land under a parachute ( didnt they say he landed in a bush or something ) , then surely a plane even with a dead engine would glide further ? ( but that obviosly doesnt mean that he could have got to somewhere safe to land - in which case the parachute would likely have still been the best option )

[baronbeeza]

As regards the decision as to whether to stay or go then I am sure the pilot has put many minutes thinking into it. Hours probably.
The problem is that they would have all been after the event. From the moment the engine snuffed his priorities were probably along the lines of engine restart ? Pax safety, personal safety.
The engine appears to be one of those ones where it is an easy decision, no point wasting more than a second on that one.
OK, brief the Pax and address their options. They are bailing, - fine. While watching them all depart he would then be thinking of himself, and he has already observed that they all made it under silk.
The more recent training may have kicked in at this point. It was probably just a matter of days earlier he had extensive instruction on how to bail and use the chute.
Personally I think the aircraft 'empty' would have been a capable glider and with the strong landing gear there would be a good chance you could pull off some form of forced landing.
That said I was not in the machine watching the altimeter winding down while the pax departed. I was not looking out the front seeing the water and whatever else lay there. He may have maneuvered a little to give the parachutists somewhere to land.
He may have also been going through his personal drill while watching the others so the bailing may have just taken seconds once they were clear.

I think all pilots would try and save the machine, well in the back of the mind, but sometimes other urgent decisions have already been made. He must have been marginal for chute deployment altitude so that would have been forefront on his mind.
I have never jumped but I would imagine he would have been thinking I am out before 1200' (or the true figure) or I lose that option.

I think we all have to be impressed that they were sitting about drinking coffee 10 minutes later.

[noooby]

He may also have been thinking about the only other 750XL to ditch and the fatal outcome of that controlled ditching by a very experienced pilot, albeit on the open ocean!

[suthg]

It may have been that the plane was heading west towards the lake, still over land, if he was to try and deadstick the plane back to ground, he may have had to come back through the path of the parachutists, get back over SH1 and land in a rough field with no guarantee of surviving a rough landing. His best option for his own life was to get out when he could - as he did.

[kiwithrottlejockey]

More likely he didn't have time to think about bugger-all.

As others have commented, the fan stopped, flames were coming out, the other occupants of the aeroplane exited, and the pilot was wearing a parachute.

No brainer, really.



As an aside, I flew gliders with the HB gliding club many moons (decades) ago. I was also jumping out of aeroplanes at the time. A couple of the senior club members admitted they used to get nervous when another glider pilot (who was also a skydiver) and myself strapped parachutes on then went flying into “wave” in the club's gliders. I guess they reasoned we'd have less hesitation in abandoning a glider if it turned to custard than the other club members due to the fact that jumping out of aeroplanes was a normal activity to us.

[lindstrim]

I recall reading in Mr Sullenburgers book him talking of a report about USAF pilots waiting too long trying to save an aircraft that was beyond saving, and as a result did not survive the ejection. Something that if I was the pilot would just be floating around in the back of my head.

[The Red Baron]

If you put Waitahanui into Google Earth theres only forestry,broken hill country or the lake for a landing.

[bounce]

[oj]

I am confident that it had a gearbox seizure of some type.
If you look at the photo in the Waikato Times of 10/01/15 and the associated video
www.stuff.co.nz/national/64792912/plane-wreckage-pulled-from-lake-taupo
you can see the propeller is grossly misaligned with the engine thrust line.
Damage of that severity would not occur during a water entry from that height.

[isc]

I'm not a pilot, but unless there is no option, in event of emergencies such as occurred here, you do not turn any more than absolutely necessary, to turn without power is to loose altitude(I know, telling granny how to suck eggs). isc

[Dave Homewood]

Let's leave all the speculation aside and await the CAA investigation results please everyone.

[bounce]

Students are usually taught to select a landing site no more than about 30 degrees left or right of the current heading in the event of an engine failure after takeoff. This both focuses the attention on landing somewhere survivable rather than trying to find somewhere perfect, and reduces the chances of a loss of control making a large turn at a reducing airspeed.

However with experience a turn back to the runway can be possible. I know of private owners who have practiced first at altitude then from the runway to determine both the plane's and their own performance. Ie a turn back can be conducted at MTOW with a y knot headwind once above x hundred feet by maintaining a z degree AOB turn.

Of course, in doubt better to land ahead. Put it on the ground in one piece and you can walk away from most (ref Foxpine PA-28). (or you can jump if so inclined!)

[craig]

Regarding the jump or stay with the aircraft decision. The pilot had seconds to make a decision before he had lost too much height and it was too late to make a safe exit (insufficient height). In that time he would have had to access the landing options but also if there was a fire risk (remember the engine has just exploded) All pilots are trained to be able to carry out forced landings. But the options are far more grim if your aircraft is on fire.... So given the time pressure involved and the eventual outcome (all survived unharmed) I believe he made a good choice. No one likes to see an aircraft wrecked, but they are replaceable.

[baronbeeza]

Sparks and grinding noises on a PT6 are normally associated with a turbine rub, given that the prop stopped on a free turbine engine then it limits the possibilities.
As we know failures on this type, albeit there are 3 different variants within the series, are extremely rare.
The smaller and medium sized engines are generally very good and the only PT6 stoppage I have ever been involved with was on the back cover.
It was a Dash 42 (Medium) and the King Air sheared a drive in the accessory gear, no fuel pump or FCU so engine shutdown.
It was in Northern Kenya and the pilot coincidently was fellow Kiwi, Helen Schrafft. She did well to retrieve the aircraft and I believe she is still flying in Africa decades later.
I think we worked out that those engines fitted with the air-cond were more susceptible to that particular type of failure.

Many jet engines have had internal core distress though and grinding noises and sparks are relatively common. It would need to be a blade or disc failure to bring things to a stop. I am not aware of any uncontained failures on the PT6 though, others here may be a little wiser.

As has been suggested, the report will expand upon the sequence of events and any background to the failure.
While I don't expect the CAA report to be made public any time soon I would like to think P&W will be acting in double quick time to do their investigation.
Operators and owners will be wanting some form of assurance that their engines are not going to be adversely affected so it a nervous wait for many.
My experiences with Pratt, and the other manufacturers of the engines I am rated on, would normally have the engineers seeing a Tech release within weeks. This may be more to do with materials, maintenance activity or whatever and purely related to the engine failure. The aircraft loss is subject to the normal investigation and report which obviously could also be expected to offer expansion on the engine issue.

In military parlance, a SOR or Defect Report, has already been filed and they won't be dicking around for two or three years waiting for an outcome there.

[starr]

Interested baronbeeza in your remarks about Helen Schrafft. A blast from the past. I remember her when she was instructing at Ardmore. Her husband Fred was brought up on a small farm across the road from the Papakura Military Camp. When we were young boys, Fred used to come and catch eels with me on my father's farm at Ardmore.

[baronbeeza]

I am thinking the Kenyan incident must have been about 1994 and Helen and her daughter were living in Nairobi at that time. I never met Fred but it must have been not that long beforehand that he tragically was killed in the forced landing of a Cessna 404 (I think it was). That may have been in the Sudan also.

I admit I had to do a Google to get the surname spelling.
www.edcoatescollection.com/ac1/austcl/VH-FLF.html
www.pprune.org/where-they-now/526772-helen-schrafft.html

It seems she has been in Africa long enough to be no stranger to that particular bar. I am guessing a few here would have frequented the Aero Club of East Africa in Nairobi.


*** EDIT ***

If only to get back on topic a little I did some research into Helen's incident. Nothing yet but it must have been just weeks after the DC-3 took out itself and the Twin Otter at Lokichogio. The DC-3 wreckage was still there while we were doing our repair job on the King Air.

I did find this rather interesting thread though.

www.airlinepilotforums.com/technical/65850-pt6-failures.html

Some of those King Air incidents would have been on the 90's with the smaller series of the PT6. The Dash 7 has Dash 50 engines and they are the start of what I would term the big PT6's. Quite a different engine to the smaller brothers and they number up into the 60's with Dash 65 and 66 being popular.

** EDIT & CORRECTION **
en.wikipedia.org/wiki/Pratt_%26_Whitney_Canada_PT6
I see Wikipedia has the big series starting at the Dash 64. A little different to what I had in mind. It will be the number of axial compressor stages they are using.



aviation-safety.net/database/record.php?id=19931107-0

If that was Nov 1993 then I think our date would be about mid-Jan 1994.

The pic shows the Caravan in the background took a smack as well. Interesting that all three aircraft that got damaged were PT6 powered.



This next video is of the large engine with a two stage Power Turbine and different fuel control components. Similar to the new Texan engines..



You may have heard Patrick mention the rotating speeds, over 30,000 rpm and with the free turbine it is so free it is actually spinning in the opposite direction to the Gas Generator turbine.
You can see how slowly the rig is motoring over the crank boss and then the Power Section rpm, that is what is happening when you haul on the prop of a PT6.

[baronbeeza]

I have posted a few links and mentioned the various types of PT6 engine. Here is another cutaway showing how with the reverse flow and free turbine engine they have managed to get the hot section at the very front. This is one of the small engines.



I mentioned the three basic members of the family but ignored the small series with different reductions, the engines within the series Dash 110 to 135.

The trick there is to add one, subtract one.
by that I mean that the 114 which powers the Caravan could be considered to have say the core of a Dash 15 but with a different reduction drive. Different prop speed.

The PAC 750XL is powered by the PT6A-34 which was also the same engine fitted to many Bandeirante aircraft. It is classed as a 'small' PT6A.

www.pwc.ca/en/engines/pt6a-34