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French Lighthouse Ops incident, 6 July 2022

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French Lighthouse Ops incident, 6 July 2022

Old 11th Jul 2022, 07:28
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Megan - I'm not saying some oil doesn't get to the exhaust, the vent is designed to push excess oil vapour out into it to be burnt off - but that amount of smoke would need a huge amount of oil (not just vapour) to be pushed out and the amount of negative g required to do that just doesn't seem evident from that video.
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Old 11th Jul 2022, 08:59
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Originally Posted by Nubian View Post
Edit
Missed your reference to the Wikipedia of accident reporting. I read a lot of those listings, but as whoever can contribute their more or less accurate information, I take the info with a slight pinch of salt. In this case, a rather large one…..reading the rest on ASN. This info might come from this very thread in the first place, like the media has been collecting “facts” before…
Quite - not always recognised. I have contributed to one entry directly, and seen narrative in the same incident that came from a post I made on PPRuNe!

Revision history:
Date/time Contributor Updates 06-Jul-2022 22:13 Iceman 29
Added 06-Jul-2022 22:15 Iceman 29
Updated [Embed code] 06-Jul-2022 22:24 Iceman 29
Updated [Narrative] 07-Jul-2022 06:42 SMue Updated
[Narrative] 07-Jul-2022 06:55 harro
Updated [Category] 07-Jul-2022 07:49 RobertMB
Updated [Time, Damage, Narrative] 07-Jul-2022 14:43 Iceman 29
Updated [Source, Embed code, Narrative] 07-Jul-2022 21:00 Iceman 29
Updated [Source, Narrative] 07-Jul-2022 22:21 Aerossurance Updated [Nature]
Corrections or additions? ... Edit this accident description
The video of the AS350 ditching into the East River in 2018, does not show the same evidence of 'chalk' after float deployment.

Last edited by 212man; 11th Jul 2022 at 09:10.
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Old 11th Jul 2022, 09:59
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It would take sackfulls of chalk to make a cloud as big as that, apart from which it is plain to see that it is streaming from the exhaust, not just appeared in one big puff from underneath the fuselage.
How much white smoke do you get in a flameout relit by the auto-igniter? Airflow into the intake must have been pretty chaotic at the start of that manoeuvre. I'd guess there would be some?
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Old 11th Jul 2022, 10:03
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Do we have a new pope?
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Old 11th Jul 2022, 10:06
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^ ^ ^ ^ ^ ^ ^ ^ ^
+1 to the above (meleagertoo). And to all the others who realised it was engine related and emitted from the exhaust.

It couldn't possibly have originated at the floats then magically be jetted directly out of the exhaust!
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Old 11th Jul 2022, 10:14
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Originally Posted by [email protected] View Post
So explain exactly how so much oil - that is a lot of smoke - gets from the reservoir to the exhaust, it is only a breather pipe after all.
Just the typical reply from you when your bias is questioned.

As you ask this way, I’ll ask you to explain exactly how much powder needed for this cloud to form, or how much nitrogen would be needed? And more importantly how it can escape the system and yet fill the floats normally?

As to how much oil needed, I know that a very small amount of oil in/on the exhaust produce lots of smoke. I lost about 4 quarts of oil when a oil cooler blew in my early days in a R22. Only a few ml’s in the landing phase, but as it was dripping onto the exhaust pipe it produced quite an impressive amount of smoke, we are talking about drops.

But hey, you’re the expert…..!
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Old 11th Jul 2022, 10:21
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Originally Posted by meleagertoo View Post
How much white smoke do you get in a flameout relit by the auto-igniter? Airflow into the intake must have been pretty chaotic at the start of that manoeuvre. I'd guess there would be some?
In order to have auto-relight in the B3, you need to recycle the startswitch and even the newest model require 1000ft Agl to do it safely, the old models 2000ft. And looking at the video, I’d like to shake the pilots hand, capable to recycle that switch during this manoeuvre….. let me know where I can find him, maybe in the UK?!🤔
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Old 11th Jul 2022, 11:48
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Looks like a labyrinth seal failure - briefly - had one on another aircraft and it's produces a massive white cloud. I can imagine the abrupt change in power could reduce the engine internal pressure and defeat the labyrinth seal briefly allow pressurised oil straight into the exhaust.
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Old 11th Jul 2022, 12:35
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A lot of debate over the source of the smoke (or whatever), but I join the crowd who consider it to be from the exhaust (for whatever reason). The floats inflate a fair bit afterwards, first starboard side and then (still later) port side. I remember some footage on YouTube years back of a US media helicopter making an emergency landing in a carpark while being filmed by another helo. It also released a hell of a lot of smoke, but not just for such a short time, rather all the way to the ground and after safe touchdown. The motion of the helicopter as it descends in this case looks somewhat irregular almost as if it is being acted on by a sling line under tension at some stages?? I have seen RC helicopters 'thrown around" like this, but never realised a full sized helicopter could also react this swiftly.
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Old 11th Jul 2022, 17:05
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But hey, you’re the expert…..!
rather a snarky reply but if most think it is oil in the exhaust then I'll just agree to disagree until someone can explain how a lot of oil gets there and for only a short period before returning to 'normal' running..

I suggested the float gear and the nitrogen as a possible explanation without analysing the video frame by frame - it is also possible it was neither that nor the oil in the exhaust.
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Old 11th Jul 2022, 18:18
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JOKE
“It should be obvious to all that what we are witnessing is the first known successful operational deployment of. the secret “Auto Smoke Crash Position Indicator” ASCPI. (TM protected, patent pending)
FROM the RFM ASCPI Supplement : “Anytime the system detects the following conditions : more than -1.5 G and a attitude of +75 Degree’s nose down and a VSI of -1000 FPM at less than 120 ft. Rad Alt, Engine oil is injected into the exhaust by the ASCPI system. This creates a large smoke cloud to indicate a Position Datum Point at which to initiate Recovery Operations.
If the float system is “Armed” for overwater operations activation of the ASCPI will also activate float deployment thus aiding in debris recovery.”
JOKE OVER.

I’m just glad nobody was killed or seriously injured during this event.
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Old 11th Jul 2022, 19:25
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I watched it a bit closer. The smoke starts while descending, the floats pop while climbing again. Quite a bit of time in between. The smoke stopped pretty quickly after regaining a normal attitude. The smoke looks like it is above the tail boom. If that much smoke would be produced by popping the floats, we would never have tested them inside the hangar. My bet is on the engine, not the floats. And one does not need a lot of oil to produce a lot of smoke.
In that situation I can see myself easily popping the floats, just in case.
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Old 11th Jul 2022, 21:21
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Here's the first frame when the smoke appears.



The smoke ending, looks like coming from the exhaust.


First frame of the floats inflating.


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Old 11th Jul 2022, 21:44
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Originally Posted by [email protected] View Post
rather a snarky reply but if most think it is oil in the exhaust then I'll just agree to disagree until someone can explain how a lot of oil gets there and for only a short period before returning to 'normal' running..

I suggested the float gear and the nitrogen as a possible explanation without analysing the video frame by frame - it is also possible it was neither that nor the oil in the exhaust.

Snarky or not, I'll try to explain.


There is always some pressure in the return oil to the tank, which is necessary to vent off from the reservoir to prevent pressure increase in the system which in turn would push the oil through the engine where it will be burned and empty your reservoir in a fairly short time (which a clogged breather line will do)

As you have air in the top part of the reservoir in normal conditions, only the vapours are being vented off. An abrupt uncontrolled manoeuvre like in the video (possible caused by a pull from the external load), the oil will end up in the top of the tank where the breather line is attached and the pressure in the return will push the oil out instead of the vapours.
As the manoeuvre is back to normal with positive G's, the oil stop being vented overboard and the smokes stops..... as I said earlier, it does not need to be a lot of oil to produce this amount of smoke.
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Old 11th Jul 2022, 23:30
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Solved!

The Chemtrails reservoir self-void function deployed as the computer only assessed a crash as 'likely'.
It's clear that it didn't assess the crash risk as 'imminent' or as we all know the pyro-charge would have fired to incinerate the agent which creates a spectacular fireball.

Phew! Got away with it agan!
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Old 12th Jul 2022, 03:12
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Originally Posted by meleagertoo View Post
Solved!

The Chemtrails reservoir self-void function deployed as the computer only assessed a crash as 'likely'.
It's clear that it didn't assess the crash risk as 'imminent' or as we all know the pyro-charge would have fired to incinerate the agent which creates a spectacular fireball.

Phew! Got away with it agan!
So Meleagertoo, your basicly suggesting that the helicopter sh** itself
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Old 12th Jul 2022, 06:36
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OK OK I give in..........
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Old 13th Jul 2022, 09:01
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I think you will find that the 'puff of smoke' is talcum powder used in packing the floats, just blew away when the floats were 'popped'
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Old 13th Jul 2022, 09:16
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Originally Posted by bluesafari View Post
I think you will find that the 'puff of smoke' is talcum powder used in packing the floats, just blew away when the floats were 'popped'
This has been discussed already, the smoke clearly comes from the exhaust
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Old 13th Jul 2022, 09:44
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Originally Posted by bluesafari View Post
I think you will find that the 'puff of smoke' is talcum powder used in packing the floats, just blew away when the floats were 'popped'
"I think you will find that...." sounds very patronising. However, that said.....

I think you'll find, if you look more carefully at the video, and take into account all the wise information from others who apparently understand the issue better than you, that it was from the engine / exhaust, not talcum powder. I am unaware of any engines that run on talcum powder.

Last edited by pilotmike; 13th Jul 2022 at 09:59.
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