Oh Continental, what have you done now?

PaulS

Touchdown! Greaser!
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PaulS
Rumors are out there that Continental IO-550 NA and turbos have a potential defect that may ground certain engines. Supposedly the problem affects all IO-550s made since June of 2021. SB in the works. This sucks.
 
Wonder if that’s why I’ve seen an uptick in late model SR22s hit the market.
 
Are you talking about the intake valve AD that came out a week or so ago????

And BTW involves part from Superior Air Parts, NOT Continental????

"Airworthiness Directives; Continental Aerospace Technologies, Inc. Reciprocating Engines With a Certain Superior Air Parts, Inc. Intake Valve Installed"
 
Are you talking about the intake valve AD that came out a week or so ago????

And BTW involves part from Superior Air Parts, NOT Continental????

"Airworthiness Directives; Continental Aerospace Technologies, Inc. Reciprocating Engines With a Certain Superior Air Parts, Inc. Intake Valve Installed"


Negative, supposedly this one involves a circlip that holds a pin in place, which in turn holds a weight on the crankshaft. People are grounding planes with these engines until more info comes out. Not a good situation. If you have an IO-550 built in June 2021 or after, you need to get this figured out.
 
It'd be nice if we enjoyed the consumer protection largesse automotive customers enjoy. Heck, my sonata has a transferrable lifetime warranty on the craptastic theta II engine, as long as the code that pops is the bearing knock trigger as modified by the software update. Free engine and rental costs. Getting Lyco or Contii to honor 1/10th of that? Fat chance.
Joke of a "market".
 
Cirrus has grounded all planes they control as a response to the information provided by CMI.
Prelim information is a pin was installed backwards which keeps the counter weights in place.

Tim
 
Cirrus has grounded all planes they control as a response to the information provided by CMI.
Prelim information is a pin was installed backwards which keeps the counter weights in place.

Tim
A retainer clip that hold the counterweight pins in place was installed backwards in some builds is what I understand.
 
well....always good to wait for a while....before you dip your toe in. :D
 
June of 2021, whew, just made it. I think I bought mine in 2019.
 
Built by Continental I assume? (so a new or reman from them?)
Brand spanking new from Continental. Against my better judgement, but I didn't have a whole lot of options.
 
If Cirrus has taken action on it, there must be some official publication.
Link to SB or other?
(newly oh'd tsio-550 owner)
 
If Cirrus has taken action on it, there must be some official publication.
Link to SB or other?
(newly oh'd tsio-550 owner)

It's coming from Continental. I heard an SB that will probably become an AD. It's not out yet. Cirrus is being proactive.
 
So how big of a fix is this?? Admittedly my knowledge regarding engines can be displayed with crayons.
 
So how big of a fix is this?? Admittedly my knowledge regarding engines can be displayed with crayons.

If it’s a retaining ring for a crank damper some cylinders are going to be coming off at a minimum.
 
Inspection of the clip will require removing two cylinders. So that much can be done without removing the engine.

Don’t know about repair, if it turns out that the clip was installed wrong. I’m sure Continental’s service bulletin will tell.
 
Inspection of the clip will require removing two cylinders. So that much can be done without removing the engine.

Don’t know about repair, if it turns out that the clip was installed wrong. I’m sure Continental’s service bulletin will tell.

There's a lot of speculation as to what the problem is, it could be as simple is spinning the clip to the proper orientation, or it may need to be flipped. Hopefully it is not anything more.
 
Perhaps?
16-41 #10
 

Attachments

  • M-18 2017 1264p Maintenance & Overhaul Manual.pdf
    259.4 KB · Views: 68
Uh oh, this is getting worse and worse.....

"In an emailed statement on Thursday morning, a Continental representative told AVweb that “Continental is taking an abundance of caution regarding a potential flight safety issue. While we are currently working directly with the FAA regarding the affected aircraft, we are proactively making the decision to encourage all flights powered by a Continental 360, 470, 520, 550 engine manufactured between June 1, 2021 through February 7, 2023 to pause flight until further information is available.”"

Cirrus Grounds Its Own Planes, Warns Operators Of Engine Issues With Some SR22s (Updated) - AVweb
 
Basically Continental had an improperly trained employee or vendor assembling counter weights on the IO550 crank shafts for the last 19 months with no quality control.
 
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Oh boy. My hangar neighbor put 3 new io-550's on 3 bonanzas this summer. I bet he's ****ed off.
 
How can one person honestly say that a clip is used backwards? Can you even define a clip? Maybe we need more backwards clips in this world for diversity.
 
There's a lot of speculation as to what the problem is, it could be as simple is spinning the clip to the proper orientation, or it may need to be flipped.
Given there's no emergency AD out, my bet based on the info so far is they are determining if this can wait until overhaul. If it is the circlip/retainer ring noted above there is a sharp side and "round" side to the these type clips due to mfr'g similar to washers. The key will be the depth of engagement of the clip in its groove whether the rounded end could be an issue. Usually if there is a requirement on clip position there is a note where to install the sharp side but not all require a specific orientation.
 
Given there's no emergency AD out, my bet based on the info so far is they are determining if this can wait until overhaul. If it is the circlip/retainer ring noted above there is a sharp side and "round" side to the these type clips due to mfr'g similar to washers. The key will be the depth of engagement of the clip in its groove whether the rounded end could be an issue. Usually if there is a requirement on clip position there is a note where to install the sharp side but not all require a specific orientation.

Continental has sent a notice out asking airplanes with affected engines voluntarily ground. This is definitely becoming an AD and it will be a fiasco. The overwhelming majority of speculation is that some of the circlips in the engines were installed backward (radiused edge in the wrong direction) and they fail to hold the counterweights in place resulting in catastrophic failure. It's apparently happened 3 times now, once being in the air. No deaths, yet.

Sucks for me as I was going to fly one of the affected aircraft from the Northeast to Florida next week. That's on hold for now, hopefully I find the plane is ok or another can be found.

I don't understand why someone like continental would use a part like this if it's so critical. I proposed on another forum that continental have the clip made oversized (thicker) then grind the radius off, then orientation wouldn't matter. Seems like a simple solution to me.
 
Continental has sent a notice out asking airplanes with affected engines voluntarily ground.
Do you have a copy of this notice? Not finding anything in public domain or TCM my subscription levels.
This is definitely becoming an AD and it will be a fiasco.
If it was a flight safety issue there would have already been an AD given you said there were 3 previous incidents. Do you have any references to these incidents and their timeframe?
I don't understand why someone like continental would use a part like this if it's so critical.
Define critical. Circlips are a proven means of securing things for ages in many different areas on aircraft. There have been other instances of improper circlip installs that didn't lead to an AD.
I proposed on another forum that continental have the clip made oversized (thicker) then grind the radius off, then orientation wouldn't matter. Seems like a simple solution to me.
The simple solution is to make sure the clip is installed correctly as have happened for ages. However, the human element always gets in the way on occasion.
 
Do you have a copy of this notice? Not finding anything in public domain or TCM my subscription levels.

If it was a flight safety issue there would have already been an AD given you said there were 3 previous incidents. Do you have any references to these incidents and their timeframe?

Define critical. Circlips are a proven means of securing things for ages in many different areas on aircraft. There have been other instances of improper circlip installs that didn't lead to an AD.

The simple solution is to make sure the clip is installed correctly as have happened for ages. However, the human element always gets in the way on occasion.

Be patient grasshopper, apparently Cirrus was notified of this on Monday, Rome wasn't built in a day, this is apparently a very big deal, I'm sure Continental trying to get it right. I haven't seen the notice, just passing on what I was told by the place I rent Cirrus from and other info from other forums. Crankshaft weights freeing themselves is a critical issue. The SB is being worked on by Continental now, they hope to have it out early next week. The consensus by speculators is it will become an AD quickly. If you have a Continental engine made after June 1, 2021, I would be paying attention to this.

Your simple solution about the clips obviously didn't work, as an engineer, I look at stuff like this and just wonder how many "but its' always been done that" way disasters waiting to happen are out there.
 
Be patient grasshopper, apparently Cirrus was notified of this on Monday,
Exactly. You hear of a production level memo and assume the worse. Yet TCM or the FAA have not informed the general public. Hmm. TCM had a similar issue back in the late 90s when new cranks were failing in flight. End result was TCM paid for the fix. Maybe the same here? Also keep in mind non-VAR cranks were allowed to remain service until case split/overhaul even though there were known failures. So there's a wide latitude on how this issue might be resolved based on my experience and speculation aside. As I stated, if it was solid flight-safety issue an emergency AD would have been out and no aircraft would be flying.
Your simple solution about the clips obviously didn't work,
On the contrary, there's is decades of operational history the clips worked just fine. Unfortunately you can't engineer a part to be human-proof. That is provided the clip wasn't installed or QA checked by a computer controlled robot.:)
 
Exactly. You hear of a production level memo and assume the worse. Yet TCM or the FAA have not informed the general public. Hmm. TCM had a similar issue back in the late 90s when new cranks were failing in flight. End result was TCM paid for the fix. Maybe the same here? Also keep in mind non-VAR cranks were allowed to remain service until case split/overhaul even though there were known failures. So there's a wide latitude on how this issue might be resolved based on my experience and speculation aside. As I stated, if it was solid flight-safety issue an emergency AD would have been out and no aircraft would be flying.

On the contrary, there's is decades of operational history the clips worked just fine. Unfortunately you can't engineer a part to be human-proof. That is provided the clip wasn't installed or QA checked by a computer controlled robot.:)

Read my post above, #24, where there is a statement from Continental asking people not to fly suspected engines. I've been told that to inspect for proper installation the rear 2 jugs need to be removed. Apparently there are 16 of these clips for the counter weights. My understanding is that for Cirrus it will take about 20 to 25 hours to perform the inspection and it can be done on the aircraft. People have been guessing this will affect 700+ Cirrus, if true that's a lot of labor, someone calculated one man would take 8 and 1/2 year working 8 hour days.

The Circlip deal, I get it, there are millions if not billions of those in service across industries. I used to use them in products and we would buy hundreds of thousands of them. They are great. But most use is not potential life or death if it fails. I'm guessing for this particular application TCM probably uses about 20,000 or 30,000 per year, which in the scheme of things is nothing. I hope if they don't redesign, they consider a fix like I mention above to make the direction of the clip not critical. I'm still struggling as to why the pin can generate enough force to move the clip out of it's groove. I think more is going on here, either clips that are not hardened properly or incorrect grooves. Those internal grooves are difficult to machine consistently and difficult to inspect.

I also wonder why those counterweights aren't forged into the crankshaft. Lots of questions.
 
Because they're not counterweights. They're vibration dampers which need to "float" to tune out crankshaft ringing.

CRKSH DAMPER CWT, Crankshaft Damper Counterweight. Thanks for the explanation.
 
I've been told that to inspect for proper installation the rear 2 jugs need to be removed.
Seems to be same area of concern from the 1998 crank cracks I mentioned early. Per that SB it involves a similar type procedure and the same weight bushing install, i.e., circlips.
http://www.tcmlink.com/pdf2/msb99-3c.pdf
I think more is going on here
This. Especially if it is similar to the previous issue in 1998.
I'm still struggling as to why the pin can generate enough force to move the clip out of it's groove.
Page 17-18 shows a diagram complete with the note where to install the ring sharp edge. There is a bushing and retaining plate in addition to the circlip. Seems it would take quite a bit to get the pin especially under load. Maybe this is a FOD issue vs failure mode?
http://www.aeroelectric.com/Referen...ental_IO-550-abcgnpr_Overhaul_Manual_2000.pdf
 
A post on another forum seems to indicate that if the engine has lasted 200 hours, it is fine. It seems they are getting more information about the issue.

https://www.continental.aero/Potential-Safety-of-Flight-Issue.aspx

"Continental proactively recommends that all flights powered by the aforementioned engines with less than 200 operating hours be limited to 5 additional flight hours with the essential crew to position the aircraft at a maintenance facility. To further clarify, Continental engines with over 200 hours may continue normal flight operations. "
 
Potential Safety of Flight Issue
  • Continental has identified a potential safety of flight issue for aircraft equipped with Continental 360, 470, 520, 550 series engines and replacement crankshaft assemblies. Consequently, Continental is preemptively advising that an inspection should be performed to confirm that the crankshaft counterweight retaining ring was properly installed in new and rebuilt engines assembled between June 1, 2021, and February 7, 2023. This advice also applies to replacement crankshaft assemblies manufactured between June 1, 2021, through February 7, 2023. Continental proactively recommends that all flights powered by the aforementioned engines with less than 200 operating hours be limited to 5 additional flight hours with the essential crew to position the aircraft at a maintenance facility. To further clarify, Continental engines with over 200 hours may continue normal flight operations. A service bulletin with affected serial numbers will be forthcoming.
 
“To further clarify, Continental engines with over 200 hours may continue normal flight operations.”

I wonder why?
 
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