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

[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.

[cncpc]

What is your point? What does any of this have to do with the subject of this thread? This was a landing accident at low power.

[hoptwoit]

Thanks Magic Wand

I don`t really want to talk about the other system like the Senica as it is the one most understood. It is not the system used on the Navajo. I found another interesting except. This one comes from:
DATE: November 22, 2004 Service Bulletin No. 369J
(Supersedes Service Bulletin No. 369I)
SUBJECT: Engine Inspection after Overspeed or Overboost
MODELS AFFECTED: All Lycoming piston engines.
TIME OF COMPLIANCE: As required by the subject bulletin

PART II – OVERBOOST
The maximum manifold pressure of turbocharged engines is controlled by various means:
1. Throttle controlled by the pilot. Here maximum rated manifold pressure is red-line and is normally
reached somewhere before full-open throttle, depending upon density altitude.
2. Preset density controller. This controller senses compressor discharge density and varies the manifold
pressure to ensure the engine develops rated power, up to critical altitude, regardless of the density
altitude. Here take-off is at full throttle. However, the red line on the manifold pressure gage is the
maximum permissible for a hot day at high field elevation. See the airframe or engine operator’s manual
for standard day manifold pressure, realizing that full rated power will require a lower manifold pressure
on a below standard temperature day and higher on an above standard day. This further indicates that
should the density controller be improperly adjusted or malfunction, it is possible to have an overboost
without exceeding red-line manifold pressure.

[cncpc]

A thread about a tragic 703 crash while working for a controversial operator interrupted and disrupted by two individuals who think their arcane and totally unrelated mutual reacharounds are more important than the discussion about why four people are dead.

Start a thread titled "Whee, Look At Us and How Much We Know About Turbochargers" and leave the adults alone. Use all the red type you want.

You'd almost think these guys were planted by Keystone.

[hoptwoit]

What is your point? What does any of this have to do with the subject of this thread? This was a landing accident at low power.

my point is I don`t know why I even bother posting here. A theory was floated about the prop looking feathered how much power would like the remaining engine to develop 100% or 80%. Read.

I am not saying that was the cause of the crash but there are alot of people reading this many are possibly Navajo drivers. I thought it was important to understand the aircraft you are flying. Since

This was a landing accident at low power.

you already know why the crash occurred. you could call Transport and save us some money and time.

[hoptwoit]

A thread about a tragic 703 crash while working for a controversial operator interrupted and disrupted by two individuals who think their arcane and totally unrelated mutual reacharounds are more important than the discussion about why four people are dead.

Start a thread titled "Whee, Look At Us and How Much We Know About Turbochargers" and leave the adults alone. Use all the red type you want.

You'd almost think these guys were planted by Keystone.

wee look ant me I fly an airplane and I dont care how it works or why my engine just quit.`

Ìm not posting for my benifit.

[spaner]

Hoptwoit, up untill then, I was going to say, wow man you have a great demeanor, and I'd be glad to know ya. Cu'z this is how discussions should go, and then everyone can maybe learn something, which is why we're all here. Maybe a link would have saficed though...he's mad cu'z he had to read through all that, and your right, he doesent care. They can go back to the grim, after we're done.

BTW, those numbers are for the A2C...

Even the Service Letter 550B, shows it at 46.5" in the type table for the J2BD.
310 VS 350

http://www.aeromanagement.com.au/navajo/SL%20550B.PDF

And, the Super Chieftain 1 STC, is predicated on the fact of engine production of 49" of boost, in order to upgrade to the "7368" NEW TO weight.

http://rgl.faa.gov/Regulatory_and_Guida ... 0192SE.pdf

But, we agree right? More MP + more power...

You like how I did that ah, I waited until they committed to a specific setting, and then buried them...
Even "flyinthebug" commits to the fact that he sets his 310s and 350s the same, @ 42"...ah, ya,..OK..
Sometimes I think that it is not intentional, just that these operators are oblivious, because of the erroneous information that has permeated the industry. Check the gage in the panel for red-line power, if it don't get there, don't fly it.

You're ass is safe, or you don't fly, PERIOD.

You want me to attach the performance charts? For TO @ 7368 short field and the SC1 requirements for the FAA STC?

[Doc]

C'MON guys. Back on track. Okay? Oh, and spaner, there's 2 "N"'s in spanner. Thinking you meant the wrench.
hoptwoit, we do appreciate your obvious wealth of knowledge. Not being a wise ass here, we do. Just probably, not now.
cncpc man, you're just being down right rude. The "plant" comment was in particularly poor taste.
Richard Cranium, we're happy you seem to have left the building.

Back on track now....play nice. These threads have a nasty habit of either getting locked or going away altogether when they go astray. This one is headed astray.

Okay, and lets drop the puck.....

BTW, I know for SURE I've had more inflight engine shut downs than any five pilots on this board combined. If I even suspected the "company" had the boost turned down, I'd address the culprit with a "spanner"....a really big one!
I have also found (with the exception of a certain Apache on a muggy August afternoon in Chicago) that VERY rarely do you need to use max power on the good engine to bring it home....but it better be available. 'nuff on engine failures. There is NO proof one occurred in this accident.

[spaner]

I accept your cease and desist Sir,

No I'm not changing my name

[cncpc]

wee look ant me I fly an airplane and I dont care how it works or why my engine just quit.`

Ìm not posting for my benifit.

You aren't posting for mine either. I've had 11 or 12 failures, shutdowns, or serious power losses in 33 years of flying. Only one airplane was bent. I've flown straight Navajos and Chieftains. The Chieftain is fine if everything is working. It's not so fine when one quits. Good for Doc for getting one home over 100 miles. Others haven't been so lucky. Piper killed their own test pilots in one in Opa Locka during a test flight about 15 or 20 years ago. I think chances are a fair bit better in the straight Navajos.

I used to think that you could tell something about an accident by the appearance of the props, but I have a friend with many accident investigations under his belt, and the fact is you can't, according to him. This pilot was in radio communication with someone on the ground. He did not indicate that there was any problem with the aircraft. Could have been at the last minute, not enough time to talk, but for now, nothing to indicate an engine failure.

I do care how airplanes work. I know why every one of my engines quit or had to be shut down.

If people are dicking with the maximum power availability of an engine, and the single engine performance is predicated on a higher maximum power setting, that is a serious thing. It isn't an issue in this accident. But it does sound almost criminal to me.

[2.5milefinal]

...never mind
Second thoughts, my questions would put us off on another tangent.

['CauseTheCaravanCan]

Aviation Investigation Report

Engine Power Loss - Forced Landing

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

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.

I know it's unrelated, but man, I don't know how that was TC's findings.
The "operator" used an unapproved power-setting? The operator wasn't the one flying the machine.
That same operator trained me to never let the wheels leave the ground unless the engine (on any bird, turbine or piston) reached full power/red line.

Back to the Keystone crash,
the left engine banter I'd like to ask;
if the engine was in feather, and not turning on touchdown, how would the top blade be bent at all?
Engine running or not, I'm trying to wrap my head around the physics of this, and I think there's only three ways the top blade could be "slightly"bent. As opposed to the extreme curvature of the blades we see when CFIT occurs with engines at full power.

1. The Engine was functioning normally at the time of impact, at a reduced power setting for anticipated landing in a half a mile.
2.The engine was turning at impact but not producing power)ie: windmilling, wouldn't feather.
3. The Engine was not running or turning at all, and the aircraft slid in sideways in a couple feet of snow, possibly forcing the prop. blades through a couple revolutions as they caught rough edges in the ice below the snow.
(the last scenario seems unlikely only because it doesn't look at all like the airplane slid sideways.)

Things that make you go hmmmm.

[lilflyboy262]

Is windmilling that hard to believe?
If it happened low there's probably a good chance that he never got around to feathering it.

[fish4life]

Not totally familiar with the janitrol system but if and pure speculation IF it contributed to accelerating the post crash fire would it be beneficial to turn off the system with the gear going down on every approach? would this cause the a/c to cool down too quickly and fog up ? Is this something that is done as part of a pre-landing flow / checklist for emergency landings?

Just a thought as I was reading through it because if something so simple can greatly increase the chances of a post crash fire with the only con being a cooler cabin for the last 2 minutes of the flight it might be worth implementing sooner rather than later.

[RatherBeFlying]

It will be interesting to see what the altimeter read on contact. Unless the fire melted the instrument completely, it should be possible to obtain the indicated altitude and setting in use.

I remember a glider flight when I took off in a north wind and flew about until I got low enough to head home. I began downwind at an indicated 800' and began developing a concern as the hanger and ground objects looked quite a bit larger than usual. Then saw the windsock pointing directly west and very gratefully turned final on the crosswind runway.

In 43 minutes, we had a frontal passage and my altimeter was 300' short.

[cncpc]

Not totally familiar with the janitrol system but if and pure speculation IF it contributed to accelerating the post crash fire would it be beneficial to turn off the system with the gear going down on every approach? would this cause the a/c to cool down too quickly and fog up ? Is this something that is done as part of a pre-landing flow / checklist for emergency landings?

Just a thought as I was reading through it because if something so simple can greatly increase the chances of a post crash fire with the only con being a cooler cabin for the last 2 minutes of the flight it might be worth implementing sooner rather than later.

I don't remember if it is off for landing, which would imply that it would be for takeoff as well.

I do believe that if there is any loss of pressure or overtemping while it is on, there is a kind of instant shutoff valve upstream to stop fuel going where it shouldn't. The Janitrol is normally up on the nose behind the baggage compartment on the right side. There is often another one in the back.