Crash @ North Spirit Lake Ont (4 dead, 1 survivor)

[hoptwoit]

With few exceptions.
Most importantly, and other 350 drivers can confirm, the ac will not be able to maintain altitude with one engine out, feathered or not. It will on paper, but not in practice. This is because operators will degrade (turn down) the maximum available boost level at max power. They do this for operational reasons to reduce wear and make use of full TBO numbers. If red line boost level is not available at max power, altitude can not be maintained at GW.
All manuals quote "red line power".
What is their "unwritten" standard maintanence procedure here? What are their setting?

Disclaimer: "The following statements are designed to be informational in nature, not speculative as it relates the accident that started this thread"
As an AME and a private (non multi rated) pilot. I have to say that the pa 31-350 is my favourite piston twin. It always amazes me that an aircraft that has been around so long still continues to have some of the same misconception follow it. In reference to the statement made above I can attest to the fact that some maintenace facilities turn down the density controllers on these engines to "save" the engine and or recomend part power take offs. I have always refused to do so or recommend part power take offs and here is why. The TIO 540 J2BD engine is a fine engine. The density controller is designed to "if set correctly" provide 350 HP when the throttle is on the stops props at 2575. on a standard day the manifold MP should read 42". On a non standard day the MP may read higher or lower to achieve 350 hp. Without the charts selecting your own MP for take may mean 300 hp one day 235 the next who knows. Max is 49. How much runway do you need who knows. The worse scenario is when maintenance turns down the dentity controller. Now the power available at the throttle stop will always be less than 350. The types of fields that navajos are capable of operating from can demand all 350 hp from both engines. Worse still in an engine out situation the remaining engine will need to be able to develop all the power it is supposed to. Piper Lycoming and Transport Canada have recommend against these practices but I still see the question here in the forums about part power take offs. If your company recommends part power take offs think again If maintenance has turned down the controllers get them set properly. As an AME I have always tried to give pilots all the tools they need to do the job. It is the pilots job to mange the engines, it is the AMEs job to make sure they get 350 hp to manage.

Fly safe

[Richard Cranium]

spaner, I brought one home on one, on a cold dark night many years ago. I don't recall if the boost was turned down or no, it's been a while, but we had five on board, and had burned an hour and a half out of full tanks. I flew it for about 95-100 miles that way. No big problem. We had an exhaust manifold burn a hole in itself (shop had installed a faulty manifold, quite a brewhaha over that one) and I didn't want to burn the cowling.

Cranium, wouldn't "defaulting to the safest to the safest decision....."be turning around and going home? When in doubt, chicken out is my motto. It's served me well.

You mean landing the plane b/c you are having an emergency (a failed engine, in a heavy Navajo), and covered in freezing drizzle wouldn't be the first thing that came to mind? Isn't part of your SOP's?

I honestly can't even read this thread anymore let alone participate.
Enjoy the torches and pitchforks.

Kind Regards,
Captain Richard Cranium

[Northern Flyer]

First off I agree that the thread is for the benefit of everyone here. The situation is sad and I don't think that anyone want's to seem heartless but a "respectful silence" has no place here, IMHO

Having said that, my Ho days are long gone but with the few thousand hours on type that I do have I can tell you a few things for sure. "Blowing" aux tanks on a 310 or 350 is a normal practice and is always unexpected; like watching water boil. After scaring yourself a few times you will learn to "save" the last 1/4 tank (X2), for the middle of the return leg.
Left side factor? BWDIK
Also, no matter what type (well most) of windshield ANTI-ice system, including the PA-31 series, it will be ineffective if not activated prior to the incounter. With few exceptions.
Most importantly, and other 350 drivers can confirm, the ac will not be able to maintain altitude with one engine out, feathered or not. It will on paper, but not in practice. This is because operators will degrade (turn down) the maximum available boost level at max power. They do this for operational reasons to reduce wear and make use of full TBO numbers. If red line boost level is not available at max power, altitude can not be maintained at GW.
All manuals quote "red line power".
What is their "unwritten" standard maintanence procedure here? What are their setting?
This actually cost me my last, and final, Ho job. Too smart for my own good. I would refuse to accept the aircraft from maintanence without it passing a "full power" run-up check. Easy to set, waste-gate valve adjustment. "Fire wall power setting", for emergency only.

Any 350 drivers out there want to quote their company numbers? How many inches below red line?
Yes, this industry is ugly.

From what I understand all the performance charts are predicated on 49 inches of manifold pressure, which is max boost. In the POH there is a paragraph that explains that it is common practice to set the manifold pressure to 43 inches. This is done by adjusting the density controller. All Chieftains I have flown were regularly set at 43".

On a side note, many Chieftains operating commercially have been upgraded to a 7368 lb take off and landing up-gross. This is through a boundary layer research up-gross kit. Also some Chieftains have nacelle tanks which give an extra hour or so fuel. I'm not at all familiar with the aircraft in question.

[Doc]

Just to recap:
1. a possible failed engine
2. covered in freezing drizzle/rain
3. flying in a whiteout
4. no one within 100sm to help
5. The runway is obstructed, and covered in deep snow drifts due to the gian storm.

The popular opinion on avcanada thinks he was a cowboy and has dispatched the lynch mob to his house and place of work already b/c they think someone must have pushed him out the door due to previous bad behaviour on the company's part, and b/c they think everyone who works there breaks every law in the book, for sport. So sure of this as a group,that the collective intelligence feels he descended below 500ft off profile (right to the ground I might add), on a Mexican ILS approach....


Kind Regards,
Captain Richard Cranium

1. Possible failed engine......Okay, I'll bite. Based on a poor photo? Of what? A blade that appears undamaged? In a photo? And WE jump to conclusions?
2. Covered in freezing drizzle/rain........Again, an assumption. Pretty likely to be true. A one hundred and eighty degree turn...you've heard of these....would have been the prudent reaction to this??
3. Flying in a white out. Probably, but he could have stayed on top in the bright sun, and turned around??
4. No one within 100 sm to help.....I'm confused....he could have gone to YRL and picked up fuel and waited it out....methinks that's about 100 miles? Close to it anyway.
5. Runway was obstructed...probably a NOTAM on this one. No surprise there. Again, stay on top and head to YRL??

NOBODY has called anybody a "Cowboy"...YOUR words, not ours.
This company has a "chequered" past. You can deny it, but you'd be wrong to do so.
The "collective intelligence believes he descended below 500 feet.....He kind of did...he hit the ground.

On another note, nobody is anything but deeply saddened by this very unfortunate event. But, by all means continue to be a "Richard Cranium" about it.

[Doc]

You mean landing the plane b/c you are having an emergency (a failed engine, in a heavy Navajo), and covered in freezing drizzle wouldn't be the first thing that came to mind? Isn't part of your SOP's?

I honestly can't even read this thread anymore let alone participate.
Enjoy the torches and pitchforks.

Kind Regards,
Captain Richard Cranium

NO proof there was an engine failure. NONE
As for the "covered in freeing drizzle......" I wouldn't have been there in the first place. NEWS FLASH for you DH, if you can't SEE you can't LAND! We're really going to miss you. Grab a tissue and get over yourself.

[spaner]

Wow, hoptwoit, and others, I did not expect that. An honest answer.
Hide, deflect, and BS..is usually what I get..thanks.
It's a big part of the problem in the industry. Money over saftey.
REGARDLES OF THE RULES
I did make "the deal" with every 350 operatior that I worked for.
"You make sure the boost is up to 49, and I promise to use 43"

One guy tried me, and I got the cresent wrench out...not BSing..
Fired me the next day...

My ass is safe, or I don't fly. PERIOD.

[Cat Driver]

How can aviation advance when there are Captain Richard Cranium's in it?

Where do these people come from?

[Cat Driver]

The manufacturers design their engines to produce xx power at xx maximum manifold pressure.

The manufacturer installed manifold gauges so pilots can monitor the power being produced.

How did we get to the point where people screw with engines so idiots will not over boost them?

[snoopy]

hoptwoit,
Thanks for that informative post. I have a bit of Navajo time, and was pleasantly surprised to have my preconceived notions (unfavorable) dispelled on my first flight. I found it to be a very capable aircraft when flown within the performance limitations - my only complaint was that it definitely prefers pavement over soft strips.
Cheers,
Kirsten B.

[flyinthebug]

With few exceptions.
Most importantly, and other 350 drivers can confirm, the ac will not be able to maintain altitude with one engine out, feathered or not. It will on paper, but not in practice. This is because operators will degrade (turn down) the maximum available boost level at max power. They do this for operational reasons to reduce wear and make use of full TBO numbers. If red line boost level is not available at max power, altitude can not be maintained at GW.
All manuals quote "red line power".
What is their "unwritten" standard maintanence procedure here? What are their setting?

Disclaimer: "The following statements are designed to be informational in nature, not speculative as it relates the accident that started this thread"
As an AME and a private (non multi rated) pilot. I have to say that the pa 31-350 is my favourite piston twin. It always amazes me that an aircraft that has been around so long still continues to have some of the same misconception follow it. In reference to the statement made above I can attest to the fact that some maintenace facilities turn down the density controllers on these engines to "save" the engine and or recomend part power take offs. I have always refused to do so or recommend part power take offs and here is why. The TIO 540 J2BD engine is a fine engine. The density controller is designed to "if set correctly" provide 350 HP when the throttle is on the stops props at 2575. on a standard day the manifold MP should read 42". On a non standard day the MP may read higher or lower to achieve 350 hp. Without the charts selecting your own MP for take may mean 300 hp one day 235 the next who knows. Max is 49. How much runway do you need who knows. The worse scenario is when maintenance turns down the dentity controller. Now the power available at the throttle stop will always be less than 350. The types of fields that navajos are capable of operating from can demand all 350 hp from both engines. Worse still in an engine out situation the reaming engine will need to be able to develop all the power it is supposed to. Piper Lycoming and Transport Canada have recommend against these practices but I still see the question here in the forums about part power take offs. If your company recommends part power take offs think again If maintenance has turned down the controllers get them set properly. As an AME I have always tried to give pilots all the tools they need to do the job. It is the pilots job to mange the engines, it is the AMEs job to make sure they get 350 hp to manage.

Fly safe

Thank you for this insight from an AME perspective. All our PA31-310 or PA31-350 were set for 42" @2575 rpm. I think perhaps the poster was referring to the P-Navajo (pressurized PA31P) which has very delicate engines TIGO-541 that produce 425 HP. I know an operator in Sask that has one in his fleet, and he has the boost turned down...derated to 350 HP. I am unsure of the exact MP setting. I do know he says he has to baby his engines, and even then he goes through alot of jugs.

Great info on the PA31-350! The facts you stated above are bang on the way we ran ours.

Fly safe all!

PS... Partial power take offs are dangerous period. The HP is there for a reason. As hoptwoit pointed out...use every tool at your disposal as a pilot...that includes Max Power take offs! Those IO540s are great and reliable engines (and also my favorite piston twin by leaps and bounds)

[Just another canuck]

Isn't it normal practice in the charter business to charge the client for the entire journey even if you do a missed approach and return home again? I'm not familiar with the industry myself, but a friend of mine who has flown about a thousand hours as a passenger in Manitoba says that the charter companies love it when the weather is crappy because it means they get to charge the customer TWICE. This would seem to be good for business and for safety - no pressure on the pilot to push the weather.

You tell them it is possible the flight can't be completed due to weather. It's on their nickel if they ask you to give it a try.

This isn't necessarily true... every company/flight/contract/etc./etc. can be different.

[spaner]

And...there you go.
No, let me explain it so that no one is confused.
When the shit hits the fan, and I go to "full power" (the stops).
I want to see one of two things. The gage reads 49 (red line on the gage) or the engine blows off the mounts. Saved TBO does nothing for me.

The point was that the industry "degrades" available power and a normal maintanance practice, and then does not provide the proper charts for traning....no LSTC duh

[hoptwoit]

From what I understand all the performance charts are predicated on 49 inches of manifold pressure, which is max boost. In the POH there is a paragraph that explains that it is common practice to set the manifold pressure to 43 inches. This is done by adjusting the density controller. All Chieftains I have flown were regularly set at 43".

Performance charts are based on 350 HP. not 49" MP that is an ultimate red line. The density controller will ensure the ensure the engine develops 350 HP. On a standard day 29.92 15c and 70% humidity (manual not in front of me) I believe that number is 42". The density controller makes adjustments for air density if the controller needs more MP for 350HP then you will see it if not then it will be less. The only way to check your engine (as a pilot) is find day that you can run the engine on stops on a standard day. Mp should read 42" if density controller is correct. At altitude you may see the 49" redine that is the differential pressure controller. The density controller is in charge for take offs and lower altitudes.
My point is for take offs and lower altitudes the density controller will boost as much or as little as is needed to make 350 HP without the charts and temp readings for the OAT, and DA and a few other things you dont know where that MP gauge will read to make 350 HP but if the controller is properly set you will always have 350 HP for take off.

[Northern Flyer]

Great info hoptwoit.

[Conquest Driver]

Question for Navajo drivers: I really should know but how good is the aircraft for keeping the windscreen clear in the event of substantial freezing drizzle?

There are 3 types of Navajo configurations I'm familiar with.

Firstly, no windshield de-ice.

Secondly, a small vertical rectangular heated glass plate. That's supposed to give you a small clear area to see out of. In a whiteout I can see that could be almost worse than nothing.

Neither of these configurations are approved for flight in known icing conditions.

Thirdly, a full electrically heated windshield on the Captains side of the aircraft. That; with prop and surface de-ice is approved for flight into know icing.

I don't know which configuration the accident aircraft had.

[spaner]

No, I see the confusion, have for a long time...

You see, I know turbo chargers and super chargers inside and out, I build my own.
There is also a confusion between gauge pressure and absolute.

On a standard day, like you say,
49" is about 9PSI of boost, 43" is about 6PSI of boost. Setting 43 will get you a loss of about 33% boost and turn a 350 HP engine into a 300HP engine. (rounded off)

Taking into account atmospheric changes, justifying a 43" setting is equivalent to 23.92...
Yea? Really? The opposit is also true, setting 43" gage, and justifying a "maximum-sometimes" 49" absolute...would get you to 35.92....OK, sure. Take a day when a H pressure system is sitting right over the airport and set the system. BTW, look at the engine power charts in the teck manual, for HP production under boost.
The dencity controler dynamically operates the wast-gate valve with a change in altitude, ie climbing to altitude. The adjustable pre-set is for setting the max boost level, for a standard day, in a static condition. (connection rod of waste-gate)
Again, another misconception, you do not adjust the dencity controler, it adjusts the waste-gate. Absolute pressure decreses with a climb in altitude and in order to maintain a specific manifold pressure AND HP, the waste gate is closed in proportion to the gain in altitude; untill it is completly closed. At which point the MP will START to drop. NOT rise

I know, I hijacked the thread.

Added link, cuz I don't BS

http://www.youtube.com/watch?v=yhKU10qE_68

[DHCdriver]

My ass is safe, or I don't fly. PERIOD.

I like your way of thinking. I hope all new drivers would read this. DHC

[Lloyd YWG FIC]

I'm not a pilot so my opinion is based solely on gut feeling and intuition.

I always give the benefit of the doubt to the pilots. Always. When I look at aircraft accidents I always try to figure out if something or somethings somehow let the pilots down or led them astray. Whether it be the aircraft that did not perform to expectations, a weather forecast that was not accurate, information that did not get to the crew in a timely manner, or something that the crew was not aware of, etc etc etc. I don't know what happened, but my gut says this pilot was faced with several situations that all came together at an inopportune time. Even when faced with multiple issues it seems to me that no pilot ever gives up or stops looking for a way out. Regrettably, sometimes it doesn't work out and all that is left is for the rest of us in aviation to learn something, anything, to help us all be safer in the future. We can all sit here in front of our keyboards and beat the "what ifs" to exhaustion, but in the end, we can't change the past. But hopefully we can learn something from it.

Be safe out there folks. Please.

[hoptwoit]

Sorry for this long winded post and I do not intend to hijack but this is important stuff. and I think those numbers may be a bit confusing so If this helps just one person Id be happy. As you will see below by the last reference accidents are a chain and I hope this can help shed some light on this link.
Density controller and differential pressure controller system:

engine at increased throttle for take-off.
When the throttle is opened for take-off, the pressure differential before and after the throttle valve is low. This small differential on the controller diaphragm is inadequate to force the controller valve completely off its seat. Thus the engine during climb at full power. When the throttle valve is wide open, there's no pressure differential between the two sides of the throttle valve. Therefore, the differential pressure controller remains in the normally closed position. Regulation of oil pressure, and by extension, regulation of turbocharger operation, is controlled by the density controller. This controller is designed to hold the air density constant at the injector entrance. The density controller is designed with a pressure and temperature sensing bellows that responds to changes of the temperature and pressure of the air between the compressor and the fuel injector inlet. As this temperature or pressure changes, the bellows expands or contracts, changing the position of the metering valve in the controller and the oil pressure in the exhaust bypass valve. Air temperature is significant because a higher manifold pressure is required as air temperature increases. Higher manifold pressure results in a greater temperature rise across the compressor. This is why wide open throttle manifold pressure increases with either altitude or outside air temperature. In a full throttle climb, there will usually be 3 to 4 inches between sea level and the point at which the exhaust bypass valve butterfly is closed to its design maximum.

Engine cruising at altitude.
During cruise at part throttle operation, the density controller does not control oil pressure. The valve in the density controller remains closed and the oil pressure is controlled by the differential pressure controller. When operating at part throttle, there's a significant air pressure differential across the throttle valve. The high pressure above the diaphragm keeps the metering valve in the differential pressure controller from fully closing, thus permitting a controlled amount of bleed oil to the crankcase. Thus, deck pressure cannot be too high.


I excerpted that from and explanation of the system. The part in blue is the important part. as altitude and temperature increases so will manifold pressure even though you didn`t move the throttle. The system is trying to maintain a full HP setting by compensating for altitude and temperature. The system will maintain a constant density of air for the engine thereby maintaining a constant HP. If the throttles are held on the stop in a climb you would eventually reach an altidude where the wastegate is fully closed and then the MPs would begin to drop off because the system could no longer keep up.

I will stop quoting numbers because I do not have them available and do not wish to mislead anyone.

Here is another excerpt from a Kelly Aerospace flyer about the system we are talking about.

Design differences
Lycoming engines utilize four basic styles of
controllers: the Differential, the Density, the
Variable Pressure and the Slope Controllers.
The density controller is the only controller
capable of sensing changes in temperature. It
relies on a bellows charged with dry nitrogen
to accomplish this purpose. Density controllers
are found in the Piper Navajo and Chieftain
and a handful of helicopter applications. In the
Piper, the density controller modulates the
wastegate movement at wide open throttle
while a differential controller keeps deck pressures from exceeding manifold pressures by
more than a specified amount at part throttle
settings. Density controllers are extremely sensitive to in-field adjustments. A 1/16th turn of
the adjustment screw will result in a 2-in.
change in manifold pressures. A thermocouple
probe referenced to deck temperature is
required when setting up these systems (see
Lycoming S.I. No. 1187J)


I do not believe this to be a Hijack and here is why.
As you can see from the kelly Aerospace write up the type of controller on the Navajo is used on only a handfull of aircraft.
The following is excerted from :

The Transportation Safety Board of Canada (TSB) investigated this occurrence for the purpose of advancing transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.

Aviation Investigation Report

Engine Power Loss - Forced Landing

Piper PA-31-350 Chieftain
Matheson Island, Manitoba
10 July 2007
Report Number A07C0119


Analysis
The AFM procedure for setting full engine power (throttles - full forward, check manifold pressure 43 inches) would have produced a higher engine power output on take-off than the operator's method of setting take-off power. The airport elevation and the higher-than-standard ambient temperatures would have increased induction temperatures and thereby reduced induction air density. This would have required increased manifold pressure during the take-off, which could have been produced automatically by the turbocharger controllers had the throttles been fully advanced. The engines were likely capable of greater than 42 inches manifold pressure; the left engine produced up to 49 inches manifold pressure during the return to Matheson Island. The operator's use of the procedures in the QRH had the effect of reducing manifold pressure and engine power during take-off.

Findings as to Causes and Contributing Factors
The operator used an unapproved power-setting procedure in its Piper PA-31-350 operation. This reduced engine power during take-off, and combined with the gravel runway and rolling take-off, resulted in an increased take-off distance.
The right-engine turbocharger differential pressure controller malfunctioned at a critical time in the take-off sequence, resulting in a loss of engine power.
The length of the take-off run and the timing of the engine power loss did not allow the aircraft to accelerate to its best single-engine rate of climb airspeed. As a result, the aircraft did not climb after the engine power loss.
There was insufficient altitude and airspeed to manoeuvre the aircraft to a successful landing at the Matheson Island aerodrome following the loss of engine power.

Safety Action Taken
On 27 September 2007, the TSB issued Aviation Safety Advisory A07C0119-D1-A1 (Use of Incorrect Power-Setting References) to Transport Canada (TC). The Advisory suggested that TC may wish to take action to ensure that operators are aware of the need to use approved flight operations reference material, and that they ensure that crews are using the correct flight operations references.

On 01 November 2007, TC responded to the above Advisory. TC indicated that it had reviewed the Advisory and had decided to publish it in an upcoming issue of its Aviation Safety Letter to ensure that operators are aware of the need to use approved flight operations reference material.

This report concludes the Transportation Safety Board's investigation into this occurrence. Consequently, the Board authorized the release of this report on 30 January 2008.

[magic wand]

Putting my money with hoptwoit in this discussion. Having said that if you think of a Seneca 2 with-out the density controller then I believe what spaner is saying is correct. Comparing apples to oranges..the only common item is the turbo-charger.