Holy Yikes!

[aviatoreb]

2 hours ago, gsxrpilot said:

I run my 252 LOP regularly, but never at more than 65% power. Consequently I'm never running with TIT's in the 1600's. 

That's what I do. I rarely fly LOP because to go at a fun-fast setting takes a very high TiT and to keep the TiT cool requires a low setting, but I will sometimes fly LOP for extended range - at about 55% which I can do with TiT in the 1580-1590 range.  If I were try at 75% I need to go 1650 or so which I am unwilling to do.  But the engine is smooth.  But Im not doing it.  ROP I'm running 1500-1550 depending on the specifics of the power setting and atmospherics of the day.

Edited May 2, 2018 by aviatoreb

[Danb]

47 minutes ago, aviatoreb said:

Huh - its a mystery where all that oil went. Well the tail pipe is just coked in soot so it clearly burned in the exhaust system but I would have guessed a plume of trailing smoke.  But then again the belly of my plane is still clean - which is a nice time saver since its sporting a new paint job...that yay...is not scratched at all despite the excitement.

No worry in the least - I was plenty busy handling my problems and by descending through 12k maybe I had some (minor) smoke in the cockpit and smell of burning, oil as it turned out but I was not sure what it was during flight, so I was handling it as if I had an inflight fire no matter if I knew if I was trailing smoke or not. 

I am still just really touched and pleased to know you stayed up late that night looking for my outcome and I am tickled to tell you outcome was great!

it's awesome how the flying community stay's together, concerned with one another's well being and some sort of real brotherhood. Now we need to get more young folks into flying. I was at the airport for a few hours the other day and saw no-one, years ago we had dozens of pilots hanging, rapping and just generally having a great time. If it weren't for Mooneyspace I would have almost no contact with other's with the passion for flight.

Erik if you need a ride to or from Postdam give me a yell, semi-retired has it's benefits.

[aviatoreb]

1 hour ago, Danb said:

it's awesome how the flying community stay's together, concerned with one another's well being and some sort of real brotherhood. Now we need to get more young folks into flying. I was at the airport for a few hours the other day and saw no-one, years ago we had dozens of pilots hanging, rapping and just generally having a great time. If it weren't for Mooneyspace I would have almost no contact with other's with the passion for flight.

Erik if you need a ride to or from Postdam give me a yell, semi-retired has it's benefits.

Hi Dan,  That is extremely generous of you! (And everyone else who has offered help, support, and wishes!!!).  Dan I'm sending you a PM.  Thank you!

[DonMuncy]

11 hours ago, Warren said:

@DonMuncy Do you run ROP or LOP?  I run LOP and am almost always limited by TIT.  Generally cylinder temps are 330-360 but EGT is approx. 1550 and TIT gets to 1650 as I approach 75%.  I usually have to back off a little to keep TIT 1630 or lower with a minimal speed impact.  Note:  I do have a JPI as the primary, and only TIT.  In the discussions it seems they indicate higher temps than the factory gage.

I generally run ROP. I am a LOP believer, but whenever I go over to the lean side, my wife says "what was that". She would rather spend the money and keep the engine sounding like it is going fast. You know ... if momma ain't happy ....

[Seth]

34 minutes ago, DonMuncy said:

I generally run ROP. I am a LOP believer, but whenever I go over to the lean side, my wife says "what was that". She would rather spend the money and keep the engine sounding like it is going fast. You know ... if momma ain't happy ....

My wife is same.  She can feel the engine is not quite as smooth LOP.

-Seth

[thinwing]

The turbo failures I read about or friends have shared with me present a common symptom when at altitude.The engine loses boost and than try's to run in an extreme rich condition.Engine quits but frequently will restart at lower altitude when mixture reaches a nonrich condition.Rough running is experienced during the restart due to fouled plugs.Turbo bearings start to get real noisy when starting to fail...people on the ground comment on this while taxing by.The oil loss went out the bearing space into the exhaust stream.If the flow is big enough ,you would see an oil pressure reduction...once you have pumped all oil overboard and reach zero pressure,main bearing damage is almost immediate.Sounds like you experienced the same restart that others have reported.Im assuming the prop was windmilling on your descent out of 16.5 k.Hopefully I am mistaken,but due to the zero oil pressure ,I think an overhaul is in your near future.

[N201MKTurbo]

Turbos don't have absolute seals, they depend on the pressure in the compressor and turbine side being higher than the drain line pressure. If the turbo stops spinning than the pressure on the compressor side will drop below the drain pressure and oil will flow through the compressor seal and the engine will have oil in the intake stream. This oil can foul the plugs. Another problem is the Continental fuel injection system does not sense manifold pressure or airflow like the Bendix servo. When the turbo quits it forms a significant restriction in the intake yet the fuel flow is still the same therefore the mixture will be extremely rich. 

If you were to pull the mixture way out you may have been able to get it to run again.

 

The only problem with this theory is it requires the turbo to quite before the loss in oil pressure. You would have sensed a big drop in manifold pressure. Another thing that could have caused it would have been a plug or restriction in the drain line. This would raise the drain line pressure to the system oil pressure and force the oil out both the compressor and turbine seals.

I believe your system does not have a scavenger pump and gravity drains into the crankcase, therefore a plugged crankcase vent could cause a rise in crankcase pressure and force the turbo to dump oil out its seals.

Edited May 2, 2018 by N201MKTurbo

[aviatoreb]

1 hour ago, thinwing said:

The turbo failures I read about or friends have shared with me present a common symptom when at altitude.The engine loses boost and than try's to run in an extreme rich condition.Engine quits but frequently will restart at lower altitude when mixture reaches a nonrich condition.Rough running is experienced during the restart due to fouled plugs.Turbo bearings start to get real noisy when starting to fail...people on the ground comment on this while taxing by.The oil loss went out the bearing space into the exhaust stream.If the flow is big enough ,you would see an oil pressure reduction...once you have pumped all oil overboard and reach zero pressure,main bearing damage is almost immediate.Sounds like you experienced the same restart that others have reported.Im assuming the prop was windmilling on your descent out of 16.5 k.Hopefully I am mistaken,but due to the zero oil pressure ,I think an overhaul is in your near future.

I hope you are mistaken too - but if I need an overhaul - so be it.  But reviewing the data from the flight I see that I did have oil pressure throughout, in the yellow arc.  And also the cylinders never got at all hot which I would think would happen if they had gotten starved of oil.  But yes well aware to be aware of this. Thanks.

So to all of us who have had turbo failures....yes - better awarenes ahead of time?  Better ongoing inspections?  We need to start a thread about prevention, inspection, and also what is the correct action at high altitude if there is a failure.  Also - I am curious - how often are turbos failing?  

[Marauder]

41 minutes ago, aviatoreb said:

I hope you are mistaken too - but if I need an overhaul - so be it.  But reviewing the data from the flight I see that I did have oil pressure throughout, in the yellow arc.  And also the cylinders never got at all hot which I would think would happen if they had gotten starved of oil.  But yes well aware to be aware of this. Thanks.

So to all of us who have had turbo failures....yes - better awarenes ahead of time?  Better ongoing inspections?  We need to start a thread about prevention, inspection, and also what is the correct action at high altitude if there is a failure.  Also - I am curious - how often are turbos failing?  

Based on thinwing’s post, I think if the turbo failed and you went rich resulting in the engine shutting down, you probably would see a decrease in temperature as the fuel would be flooding the cylinders. As well, in an emergency descent with the prop spinning, I suspect the CHT/EGT temps would be low.

If the oil completely left the engine, I wonder how much damage could be done to the crank in a windmilling situation. I think you also said there was some oil remaining in the engine. That would be enough to keep parts lubricated. Especially since this entire events was fairly short in duration.

I would certainly be interested in seeing your engine data. 

[aviatoreb]

1 hour ago, Marauder said:

Based on thinwing’s post, I think if the turbo failed and you went rich resulting in the engine shutting down, you probably would see a decrease in temperature as the fuel would be flooding the cylinders. As well, in an emergency descent with the prop spinning, I suspect the CHT/EGT temps would be low.

If the oil completely left the engine, I wonder how much damage could be done to the crank in a windmilling situation. I think you also said there was some oil remaining in the engine. That would be enough to keep parts lubricated. Especially since this entire events was fairly short in duration.

Yeah - and furthermore apparently my first reaction was to add a bit of fuel flow - which rose to 20gph...and for a bit then I leaned to maybe 15 (but this was while directing to the airport so it was just approximated) and anyway not only is the engine getting fuel but it is not running.  So the cylinders get quite cool.  The danger is shock cooling not overheating, if there is still oil.  I believe there is still about 5 qts in the case, since there is still a bit showing on the stick, but that will be confirmed shortly.  It had been a nice 10qts just 1.5 hrs previously.

[FloridaMan]

I’m very curious about all of this as well. First thing I’m doing after my Rocket gets out of PPI and I get it home is installing an EDM900. 

[Rumblestrip]

On 5/1/2018 at 9:16 AM, steingar said:

The only thing I can think of more dangerous than an engine out emergency in a single is eating Sushi in rural Pennsylvania.

CLOSE!

Sushi at the Pittsburg Airport.

Sincerely,

Tony Reali

(If you watch Around The Horn, you'll get the joke)

[tomgo2]

22 hours ago, carusoam said:

Look up turbo OH...  There has been a discussion around here before...

The last one I recall was our Turbo guy out in CO?  He bought into TN’d Cirrus...  (See if @peevee has some insight)

The oil seals have a tendency to wear out.  Not catastrophically as in this case...

quarts of oil leaving through the hot exhaust...  that could leave a smoke show. Depending on how much free O2 was available in the exhaust, it could have burned up quite a bit...  were you LOP at the time?  Excess O2 in the exhaust stream would be normal...

It would be interesting to review the engine drawing for the oil system... is there a provision for a turbo failure to protect the engine from running out of oil completely? (Probably wishful thinking on my part)

It will be interesting to see how damaged the turbo really is... If it got bogged down in its own crusting oil, or it ran out of oil and ceased...

 

i had difficulty searching for both words... turbo + failure...  I got thousands of turbo and thousands of failure...

 

I did come across one thread recently...

 

The other reference I had was when reman of a turbo engine... the turbo gets OHd as well... if desired...

An interesting resource we can invite to the discussion... @tomgo2 a new MSer with a turbo business supporting Mooney TNs...

Best regards,

-a-

 

Overhaul of the turbocharger is recommended at 1000 hours but not required for the RAJAY Systems.

RAJAY can offer factory remans to new specs with a 1000 hour / 2 year warranty. We are considered an OEM and can offer very competitive pricing.

Glad to hear everything turned out okay! Was this a RAJAY System or a factory install?

[carusoam]

@tomgo2

This would be similar to factory install...  The engine and its turbocharger, for the Rocket, is derived from a different Twin engine plane...

Best regards,

-a-

[Mooney in Oz]

On 5/1/2018 at 10:06 AM, aviatoreb said:

Holly Beggezuzzz!  I'm still shaking....

I will fill in later...but I just had a full loss of power at 16500...and made an immediate emergency landing - luckily on a nice smooth runway.

Sorry to come in late on this Erik, but I have only just noticed the thread after a couple of days away.  A big congratulations and very well done from the other side of the world!

Even though you had daylight, plenty of altitude and a relatively short distance to a suitable runway on your side, under immense pressure being able to achieve a successful deadstick landing at the end after a series of spirals is another matter that had to involve a highly competent degree of timing and skill.

I hope you will be invited to speak of your experience for the benefit of others at safety seminars.

Again, very will done sir!!

[aviatoreb]

9 hours ago, Mooney in Oz said:

Sorry to come in late on this Erik, but I have only just noticed the thread after a couple of days away.  A big congratulations and very well done from the other side of the world!

Even though you had daylight, plenty of altitude and a relatively short distance to a suitable runway on your side, under immense pressure being able to achieve a successful deadstick landing at the end after a series of spirals is another matter that had to involve a highly competent degree of timing and skill.

I hope you will be invited to speak of your experience for the benefit of others at safety seminars.

Again, very will done sir!!

Thank you Mooney in Oz,  The day light and plenty of altitude are both by design....having had the understanding that this sort of thing was always possible.  It would have been dramatically more challenging in low ifr, somewhat more challenging in night flight - assuming I could find a runway but if too low off field landings are tough indeed in the dark, and of course altitude gives options.

Someone asked me if I will quit now.  I sort of find that to be a funny question because I understood there is risk since many years and I came to terms with it in the sense that this event has not shocked me that it could happen. I already knew it could happen.  Thank goodness it worked out ok.  I also ride bicycles, for exercise, and statistically (unfortunately) that activity is more dangerous than flying small airplanes.  I would have to quit bicycles first which I won't do.  I am reading this thread on preventative maint. for turbos very carefully, and I have learned ALOT more about turbos in recent days.

Edited May 3, 2018 by aviatoreb

[aviatoreb]

A bit of GOOD news - there was still about 5 qts of oil in the crank case.  I had started the flight with 10...but 5 is A LOT more than zero.  SO that and the fact that the pressure did not drop below the yellow, and that cylinders stayed cool, and seems the engine itself will survive.

[aviatoreb]

49 minutes ago, David Herman said:

Good job Erik. I’ve been reading, but had no words to express my thankfulness that you are ok. Been there done that ... except I landed on a grass strip used primarily by cropdusters. It was 31 years ago now. Etched in my memory forever. 

Thank you David.   The outpouring is amazing.  Amazing.

[jackn]

Dr. Bollt, I want to add my congratulations on a job well done. Also, I want to thank you for a thoughtful, in depth write up as well. I’ve been reading & thinking. I know a turbo failure can happen, I just wasn’t sure how it would manifest itself or how I could recognize it if it did happen. Your story will stay with me. I’ve been thinking of a way an engine instrument could alert you to the fact that the turbo failed, thus giving the pilot the opportunity to lean out and restart. 

I was also wondering if the turbo were to fail, would the intake part of the turbo block the ambient air from getting to the intake manifold. I guess it would all depend. 

Oh, as an aside, there never seems to be a boring moment with you. I hope Mrs Bollt is not getting too crazy. 

Edited May 4, 2018 by jackn

[aviatoreb]

3 hours ago, jackn said:

 

Oh, as an aside, there never seems to be a boring moment with you. I hope Mrs Bollt is not getting too crazy. 

Thank you Jack.  But let me say publicly, without a doubt, my wife is clearly a saint for putting up with me.

[Yooper Rocketman]

13 hours ago, aviatoreb said:

.  I am reading this thread on preventative maint. for turbos very carefully, and I have learned ALOT more about turbos in recent days.

At the end of my ordeal a few years ago, I posted my new procedure to hopefully detect a turbo issue before total failure (the last several posts of the thread).  I still think this procedure would find a turbo nearing it's end of useful life in most cases.  Ironically Erik, you were the one with the most questions on how to conduct this inspection at that time.  Not sure if you did but going forward, after this experience, I suspect you will be like me and check that turbo during every oil change. :>)

Tom

 

[bradp]

Erik lot of good lessons for other flyers on the right way to do it.  Maybe you and Dan should contact AOPA to do one of those safety videos?  

[aviatoreb]

27 minutes ago, Yooper Rocketman said:

At the end of my ordeal a few years ago, I posted my new procedure to hopefully detect a turbo issue before total failure (the last several posts of the thread).  I still think this procedure would find a turbo nearing it's end of useful life in most cases.  Ironically Erik, you were the one with the most questions on how to conduct this inspection at that time.  Not sure if you did but going forward, after this experience, I suspect you will be like me and check that turbo during every oil change. :>)

Tom

 

I know - I have been thinking and kicking myself this week for not having commenced that inspection procedure sooner.  Somehow at the time, I did not begin immediately as I had planned since at the time I didn't actually have my airplane as it was in repairs shortly there after and I mostly forgot about it before it became habit.  This is my fault!!!  :-(. At least this stupid error on my part was a learning experience that didn't kill me.  You can be sure I am learning from it and I should have learned from your experience instead of my own experience.

Ill tell you one thing - because of YOUR postings I had previously been unaware that turbos fail and their failure mode, and at least in flight as it was failing I was aware of what was probably going on.  That was very helpful.  It helped me be a lot more decisive in my decision making,

Thanks for posting!!!

[kortopates]

Erik, I finally had a chance to catch up and  read your thread. So glad you got down safely and that especially you are fine!! Of course its also great news as well, how successful your emergency landing was to get down without injury to the plane as well   That's very cool of you to share your experience here on MS and make it a learning experience for all that are interested. 

Although inspections of the turbo are really good to do, they're helpful but no guarantee to preventing these and very possibly wouldn't have prevented this common failure. And of all the many kinds of turbo system failures this is one of the better ones to have because it does come with warning signs from the dropping oil pressure. With a few thousand hours in type I've been through this same emergency and luckily for me because I was halfway through A&P school at the time, I was better equipped  in recognizing the symptoms. I was with my wife, she was the pilot flying and she noticed the oil pressure had been slowly dropping and getting closer to the yellow arc. it was 10:30pm at night over the middle of Texas. We were on our second leg headed from SOCAL to Bahama's and we're planning on heading to Austin area for the night. But as we're watching the oil pressure at first I was actually wondering if we might make it as far as SAT where I was familiar with a good MSC. Of course I was being overly optimistic, but I had no intention of letting oil pressure drop to the yellow arc in cruise. Its important for all of us turbo pilots to understand that the bottom of the green arc, 30psi, for TCM engines is the absolute low limit permissible oil pressure for cruise power RPM. The yellow arc is permissible only at IDLE power and merely a statement that the engine may not be able to maintain the required 30 psi at idle power which is okay as long as the engine is just idling power. But its inadequate of an oil pressure to support cruise RPM power and constitutes an emergency with any engine; especially a turbo. i.e. its time to pull the power back and find a place to land now. In our case we had one more symptom that immediately made up our mind we were diverting.  Fluctuations began to appear in the oil pressure which I recognized as the oil pump cavitating with air; albeit still above the yellow arc. But seeing that, I realized the oil pressure could radically drop any second if the oil volume level dropped much more and we immediately pulled power to idle. We had already gone through our diversion options, and had selected a nearby towered airport that was still open, San Angelo that was ~15 miles off our left wing if we needed to divert. So as the PNF, I told ATC we were diverting to San Angelo due to loosing oil pressure and loaded a GPS approach commencing on the opposite side of the airport. We were at approx 17K with a lot of altitude to loose and my plan was to glide past the airport just far enough to ensure we could get down without any power if we lost the engine. With dual 430W GPS at the time, the top one had the approach loaded and the bottom was set direct to the airport or runway threshold with the VSR required to make it. We turned inbound when were down to within a 6 degree slope to the runway (1000 FPM @ 90) which was good buffer for ~4.5 degree slope our 252 needs at best glide no wind. I had practiced this several times in a full motion simulator and luckily it worked out very well. Center contacted tower on our behalf, and cleared the airspace for us and provided ATIS info and everything else we needed. When we landed on the runway the emergency vehicles were lined up on the side of the runway. The FBO gave us a crew car for the evening and got us a room. (incidentally, you'll note all my numbers for emergency slope is based on multiple of the 3 degree GS for time, dist & rate, since it keeps the math simple enough to do quickly in my head)

The following morning I worked with an mechanic. Luckily although we were down too 2.5 quarts, there was no metal in the filter nor screen.  But we checked compression's and borescoped the cylinder to rebuild my confidence in the engine. At the time we were confident that all the oil was going out the exhaust but these days I would have pulled controller to look for any induction oil pooling since I have seen minimal signs of induction oil in the induction tube past the turbo or intercooler inlet but found significant pooling of induction oil at the controller where it pools up before entering the induction tubes. (the interesting reason here is the seals may be leaking only at high altitude when working hard with virtually no leakage at low altitude e.g., 6K and less till they get much worse).   I would have had a much harder decision to make if the engine had been operated in the yellow arc at cruise power for more than a couple minutes. Its hard to say what I would have decided on back then, but these days with all I have learned since then I would not want to risk a spun bearing and would be much more cautious about it these days. Besides I expect the insurance company would not disagree with the manufacturers advice to do a tear down inspection in such a situation. (although I don't have any direct knowledge of how the insurance companies would respond).  

So that's how we learned to respond to dropping oil pressure as a turbo operator. 

Edited May 4, 2018 by kortopates

[Yooper Rocketman]

4 hours ago, aviatoreb said:

I know - I have been thinking and kicking myself this week for not having commenced that inspection procedure sooner.  Somehow at the time, I did not begin immediately as I had planned since at the time I didn't actually have my airplane as it was in repairs shortly there after and I mostly forgot about it before it became habit.  This is my fault!!!  :-(. At least this stupid error on my part was a learning experience that didn't kill me.  You can be sure I am learning from it and I should have learned from your experience instead of my own experience.

Ill tell you one thing - because of YOUR postings I had previously been unaware that turbos fail and their failure mode, and at least in flight as it was failing I was aware of what was probably going on.  That was very helpful.  It helped me be a lot more decisive in my decision making,

Thanks for posting!!!

Erik,

ALL OF US THINK about doing something new or different things based on another person's experience.  If you DON'T KNOW, then you NEED TO KNOW, this wasn't a post intending to question you.  I have done the same thing a hundred times in my life, saw a good piece of advice requiring some work on my end to accomplish it, and life and 100 other things got in the way before I did it.  There's no better example than the CO Monitors.  I read and heard a ton of stories on CO dangers, yet never acted on it until we almost lost a Mooney friend just over a year ago.  Not because I didn't believe it was worth the cost or time to get one, but because it just didn't work it's way up my priority list.

My intention now is for OTHERS to consider taking several of our scary experiences and ACT upon procedures that could very well prevent them from posting in a couple years the same experience you and I have had.

Tom