I'm not talking about covering your ass. Making an unplanned, rapid emergency landing in a populated area can very well result in an accident itself. Not wanting to do that, and weighing it against the risk of flying a mile back to an airport prioritizes saving your ass just as much.

If I had assumed I was about to have a structural failure last time I had a fire light, I would have had to land in tall trees. In my case that would've been the entirely wrong call and I could've killed or hurt myself and my passengers doing so.
In this case here it was different. The failure also happened rather quickly, even though it looks like an eternity when you watch it from the comfort of home on video.
But we don't know what indications the pilot had. Hindsight, that's all.

I'm wondering the same, as it also wasn't in the distress call it seems.

I find it hard to believe that anyone, who knows that they have an uncontained fire on board, would not elect to land immediately.

I've had 1 baggage bay and 3 engine fire warnings in my time, all of them proved to be false indications. All of them had no secondary indications, and had we continued to follow the checklist, three would have resulted in a ditching. The "confirm the fire" part of the checklist is perhaps not given the consideration it deserves, and usually offers no guidance as to what to do if you cannot confirm the fire at that time.

But if it was a school day, those fields may well have been full of kids, we probably will never know.

I have no doubt that he was unaware of the fire - my point was that he may well have followed his training and delayed shutting down a failed engine until he had time to refer to the check list.

In this case that could well turn out to have been a mistake but that is with 20/20 hindsight.

The initial FAA notice lists the accident as due to unknown circumstances.

Company policy overrides the RFM procedure? Unless there is an approved supplement?


Below would be following the RFM.

Note the reference to memory items and the requirement to "perform immediately" with the grey background when it arises.

https://cimg4.ibsrv.net/gimg/pprune....205a3c199e.png
https://cimg7.ibsrv.net/gimg/pprune....e282fcd1c9.png
OEI Flight condition - Establish - means - a condition where you can operate effectively with the "normal" engine within OEI limits

Affected Engine - Identify - means - all the Captions which will be numerous in addition to instrumentation.

Single Engine Emergency Shutdown - Perform - means ENG MAIN sw - IDLE, Check indications (confirm), then OFF.


Fire in flight only has one additional item - EMER OFF switch - which closes the fuel supply valve. IF you have Engine Fire Extinguisher fitted it will automatically fire when FIRE is active, fuel valve is closed and N1 < 55% - there is no way to activate it manually.

https://cimg0.ibsrv.net/gimg/pprune....596c30a251.png
The extracts are from a CPDS type RFM which this particular aircraft may not have been but the items are the same.

It does not appear to be a report, merely a notice related to the accident occurrence.

I'm lucky enough to only be a pax with other talented and well-trained people. But - excuse me, a fire causing terminal structural damage in 3 minutes?

Until we know the actual cause of the fire and the actions taken, it may well be within the limits of the certification.

A lot of people are criticizing this EC135 pilot for not landing sooner. We know the pilot had an engine failure - he reported that to the Tower as his reason for returning. Once the engine quit, he had a couple of things to do (e.g. secure the engine, set OEI power, attain best OEI speed, start a turn back to the airport). A lot going on and a lot going through his mind. Sure, these things don't take forever, but they eat up seconds. And in his case, he only had seconds. (And honestly, who among us - actual pilots, that is - thinks that if we get a fire, our helicopter will come apart so quickly? That's some pretty scary !!!!!) A lot of people assume that he also knew that he was on fire. We do not know this...yet. But we will. Maybe it was not a catastrophic engine failure. Maybe the fire was aft of the detectors and did not set them off (which is what it looks like to me).

At PHI, when I checked out in the BO-105, we were anecdotally told of an incident in which an in-flight fire occurred, but the tail boom fell off before the guy could get it on the ground (or perhaps it was just after he landed on the water - I forget). The point was to take EVERY fire light seriously. Perform a tight turn to see if you were leaving a smoke trail, or look at your shadow on the water if you could see it...or have a pax slide the rear door open and look. Those things were all well and good, but in the summer, I'd often climb that Bolkow up to 4,500 or 5,500 feet where the air was cool, the viz was better and there was less traffic. And it would take at least a minute or two to get down, even in a screaming descent. Which brings me to my point: What if the EC135 pilot had been higher...higher to the point that he could not get it on the ground quickly enough even if he had decided to LAND IMMEDIATELY? I cannot say for sure what I would do in this very specific case, but with an engine out and that big airport right behind me, with the field boundary nearly within gliding distance, I might have just turned around and gone back too. Until we hear what this EC135 guy has to say, I'm going to give him a huge benefit of the doubt.

Tending to think the same, if engine shrapnel had punctured the the engine deck could have allowed oil/fuel from busted lines to drain into the compartment, no engine fire indications perhaps in that case. We had a Turbomeca in a 76 disintegrate and cause oil lines to burst, caused a fire, authorities considered the design of oil lines not an airworthy installation, didn't see that idea get up though.

There has been a fair bit of discussion on that topic, but I haven't read it as criticism.
They did the best they could, under the circumstances. Hindsight is perfect vision, we will have to wait for the detail to become public knowledge before drawing conclusions, but discussing the could-have, would-have and should-haves shouldn't be considered a negative.
It can be a very fine line between success and failure, one that may be outside of anyones control.

But you have to put it into context. The process to repair a 135 tailboom requires hot bond temperatures of about 125 C. The T1 fire detectors actuate at 210 C - 270 C. Composite structural strength becomes compromised starting around 300 C. And any fuel/oil fire will burn at a much higher temperature. Given the use of heat resistant composites (800+ C) is regulated to areas that may see high heat or fire like an engine bay, the rest of the structures use various standard methods. For reference, most aluminum structures begin to structurally degrade at 600+C.

One minor inaccuracy is the N1 has to be < 50% for the fire bottle to go off.

Interesting side discussion. I wonder if this was a Public Use ops and who was overseeing the "piece-mealing" of parts and maintenance?

There's no reason you can't keep a 24 year old helicopter flying safely for many more years unless you fail to invest in maintenance and parts at the right time - it rather looks like that is where the investigation may have to do some digging.

They have sadly just learned the reason for the old saying 'If you think safety is expensive, try having a crash'.

Because the fire is at the rear, & the aircraft is flying towards the airport, perhaps? At that distance, chances are a human will see a small back dot getting closer, perhaps trailing smoke. That's discounting any buildings obstructing the view.

The farthest distance from the tower was 1,3 nautical miles, thats pretty close

skadi

Given the short flight time, fire trailing and persistent and the pilot reporting and engine failure.....maybe a turbine burst (looking like engine failure with zero Tq/Nf), That savages the tail boom flange area with shrapnel. Meanwhile the Gas Generator is still working and the FADEC response to Zero NF is to open the fuel to max chat. The fire escaping from the compromised combustion chamber finishes the job. I have no idea why the pilot did not have a fire warning or if he missed this in the mix of confusing indications.

With an engine fully failed (ie all parts stop rotating) the fuel pressure becomes zero everywhere in that firewall box and the chances of a persistent fire almost zero. Maybe!

DB

Unfortunately it's very easy to miss the fire indication on the EC135. All you get is one gong and the light on the guarded switch, that's it.

https://cimg1.ibsrv.net/gimg/pprune....8db4742561.png