PDA

View Full Version : Historical accident Chieftain at Tullamarine airport.


Centaurus
11th Jun 2013, 03:44
Way back in the 1970's (I think) a Chieftain departed Tullamarine runway 34 at night on a paper run. A partial engine failure occurred shortly after lift off accompanied by what the pilot perceived as a fire. In fact it was oil spraying on the turbo charger after the dip stick had ejected. The pilot tried for a RH circuit but due to low rate of climb was unable to out climb rising terrain and he went in. I don't recall if he feathered the prop or it was windmilling.

Could anyone supply more details on the accident which featured in Aviation Safety Digest. What was the pilot's name? The BASIS report was excellent and gave a comprehensive analysis of all the drag factors that combined to reduce the single engine rate of climb.

buzzz.lightyear
11th Jun 2013, 08:16
Your thread 23 Dec 2009 has all the info you are looking for...

Capt Fathom
11th Jun 2013, 10:13
Not sure what an Aerostar arriving at WOL has to do with a Chieftain departing MEL?
What's your thinking there Doc?

thorn bird
11th Jun 2013, 10:17
Good grief where are you guys from???
THE PILOT DID IT!!!
See ATSB The pilot always does it!!!

tail wheel
11th Jun 2013, 10:37
buzzz.lightyear.

A link to that thread as I can't find it in Search?

Thanks

chimbu warrior
11th Jun 2013, 10:51
Chieftain Melbourne - Peter Benton
Aerostar Wollongong - Gary Campbell

By George
11th Jun 2013, 10:54
PM me if you like John. I flew for AAC and Peter Benton was a friend. Yes our CASA friends blamed him. Nothing to do with a hole in a piston.
It did bring out some interesting facts on the age of the airframe and the subsequent effect on performance. These things are a further 30 years old now. There is a 1968 Navajo going strong on the Sunshine coast. The age of these aeroplanes is a worry.

buzzz.lightyear
11th Jun 2013, 11:11
Chieftain crash at Tullamarine circa 1978. Discussion points. [Archive] - PPRuNe Forums (http://www.pprune.org/archive/index.php/t-399805.html)

Found it through google using the pilot's name...

Centaurus
11th Jun 2013, 12:49
Your thread 23 Dec 2009 has all the info you are looking for...

Thanks for the reminder. The curse of the aged long time Ppruner where you forget what you have written 1000 posts ago. :ok:

mustafagander
12th Jun 2013, 06:17
As I recall it, the boost limit was out of tolerance and the live engine wasn't able to make the specified boost.

Horatio Leafblower
12th Jun 2013, 07:10
Max continuous power as specified in the POH/AFM for the PA-31-350 is 49" MAP and 2575 rpm.

Power required on the operative engine following an engine failure, according to the POH/AFM, is max continuous power.

In about 1600 hours on type I can't recall seeing a Chieftain making more than 44" boost on take-off with most of them making 41-42". :hmm:

Worse, engineers refuse to set 49" because "bloody pilots will ruin the engines" :suspect:

Better risk than ruining the whole aeroplane because you can't get book performance I would have thought :ouch:

scavenger
12th Jun 2013, 10:26
Worse, engineers refuse to set 49" because "bloody pilots will ruin the engines

It shouldn't even be an engineer's unilateral decision, if the manufacturer has specified a minimum MAP and RPM under certain conditions then that's what should be set by the engineer (I assume we're talking about setting the density controller). Are such specifications made in maintenance manuals? It certainly appears the AFM does.

It would be interesting to see whether a charge of manslaughter could be supported if it was proven the MCP was deliberately reduced not in accordance with published maintenance procedures (and I admit I don't know what they are). Fair enough if the operator has procedures that limit MAP/RPM in normal ops but to deliberately derate an engine in a PA31 so it can't get max power is criminal. Wouldn't modifications like that require an EO or STC and revisions to the appropriate performance sections of the AFM?

It might be worth defecting the next one you fly horatio and seeing what happens.

Horatio Leafblower
12th Jun 2013, 11:37
Behind me, thankfully... :cool:

expressinginterest
12th Jun 2013, 12:38
Theirs also a time limit on max continuous power in the PA31 which many gen y's simply overlook...

DropYourSocks
12th Jun 2013, 12:51
In defense of gen y, the three minute limit is only applicable with the super chieftain payload extender kit fitted.

Socks

rnuts
12th Jun 2013, 15:03
When you set those engines up you had to put a temp probe into the intake, then you get the chart from the maint manual, run the engine at full power and then match the temp with a boost setting (with regards to the chart) that gave you 350 HP.
That's why you would see different boost figures on T/O.
Boost doesn't directly relate to HP.
Changes would be due to worn components, density etc.
That's how I understood it.

porch monkey
13th Jun 2013, 00:54
Pretty much right rnuts. Traps for young players I guess. The controller will only produce the required boost to make the rated 350 hp, which varies with the ambient conditions. There is a chart available from lycoming/piper giving the correcting factors for the boost check. Never used to see much more than 44 or 45 inches on those cold MB nights. In summer tho, another story. iIRC the remaining engine on the accident a/c was found to be under performing to the tune of about 30 hp or so. There really is no way to get a max weight chieftain around a circuit under those conditions, especially if it is at the MTOW associated with the Vortex kit. SOME unscrupulous operators were intentionally setting max MAP low, thinking they were saving themselves some wear and tear. Worst one I saw was 39" on t/o. Aborted and sent it back poste haste. My reference to young players is that you wouldn't have any idea about the fiddle, unless you actually understood how the system worked, and had an idea about what you should actually get on the gauges in those ambient conditions.

P.S. Don't have one to hand anymore so I stand to be corrected, but the vortex kit stc had a 3 minute limit for T/O power, but didn't apply to engine out operations.

scavenger
13th Jun 2013, 01:14
Hey porch monkey, interesting post. Not having a go, genuinely interested in how you reconcile

The controller will only produce the required boost to make the rated 350 hp, which varies with the ambient conditions.

with the Whyalla accident ATSB supplementary report (http://www.atsb.gov.au/media/24343/aair200002157-A_001.pdf) at p19

During the inquest there was considerable discussion about the operation of the density
controller and regarding the term ‘overboost’. It became clear to the ATSB that there was
a general lack of understanding of these issues, not only by those involved in the inquest,
but by the broader aviation community. In particular, a number of myths were
perpetuated throughout the inquest, specifically that:
• the density controller would not allow the engine to generate more than the rated
horsepower of the engine (in this case 350 bhp), and
• the density controller would not allow an engine overboost situation to occur.
To assist the Coroner in understanding that over 350 bhp could be generated, the ATSB
prepared and submitted an explanation of engine overboost and operation of the
turbocharger control system. The document has been independently reviewed by the US
National Transportation Safety Board (NTSB). A copy of that explanation is at
Attachment E.

The ATSB seem to say that your point is a myth. This seems to be backed up with the fact that one of the engines was producing 375hp at one point.

And as for

Theirs also a time limit on max continuous power in the PA31 which many gen y's simply overlook...

If there's a time limit, how could it max continuous?

porch monkey
13th Jun 2013, 01:41
If there is a failure in part of the system, then anything is possible. The engine can over boost, and one of the contributing factors can be cold engine oil, for example. Not unheard of at all. Sensor failure, stuck waste gate, there are a multitude of reasons. Which is why there is a red line maximum on the gauge. You aren't to exceed that particular limit. Keep in mind, that if there is a problem with the governor system, that can also affect the output. My statement that the boost controller limits the hp is aplied to a correctly set and functioning engine. I thought you would have taken that for granted.

Also, the ATSB does not cover themselves in glory with the Whyalla investigation. I suggest you might want to research that a little more.

The 3 minute limit is for take off power, as I stated in my post. The max continuous limit is lower. Only applies to the stc aircraft, not the bog standard one. Also, your quote is not from my post, but I'll answer it anyway.....

Having reread the appendix you quote, Braly's engine produced 2% more power. It did not produce 375. That is extrapolated , therefore assumed. Once you operate outside the certification limits for any engine, you can get all sorts of results. Both good and bad. A TIO 540, in good repair, and operated within the limits prescibed by the manufacturer will give you 350 hp, maybe 1% more or less. Are we going to argue about 1 or 2%, which would be well within tolerances? Keep in mind, engines are certified on the basis that they do not produce LESS than rated power.

scavenger
13th Jun 2013, 02:13
Also, your quote is not from my post, but I'll answer it anyway.....

The comment did not apply to your post but

I thought you would have taken that for granted.


I suggest you might want to research that a little more.

That's what I was trying to do by asking you, thanks anyway.

porch monkey
13th Jun 2013, 02:24
Sorry dude, we crossed paths with my edit. The quote about gen y was not mine. I hope the edit makes my thoughts a bit clearer for you.