EH101 emergency landing

[Sikorsky]

Local news "Viborg Folkeblad", near Karup Air Base (EKKA), reports that a danish Merlin EH101 Wednesday made an precautionary terrain landing. A military spokesman says that all danish EH101 are grounded, except lifesaving flights.

Sources within the military reports that all three engines stopped within few seconds and subsequent autorotation performed to an open field.

Karup-helikoptere sat ud af spillet - Viborg | viborg-folkeblad.dk (http://viborg-folkeblad.dk/viborg/karup-helikoptere-sat-ud-af-spillet)

[whoknows idont]

Calling AR after triple engine failure a precautionary landing...?

[The SAR RC]

Is this a first in helicopter aviation? A triple engine failure.

[GipsyMagpie]

Are the British ones grounded too?

[Self loading bear]

Or a double pilot failure
Or a single fuel failure

[GipsyMagpie]

Sources within the military reports that all three engines stopped within few seconds and subsequent autorotation performed to an open field.

Karup-helikoptere sat ud af spillet - Viborg | viborg-folkeblad.dk (http://viborg-folkeblad.dk/viborg/karup-helikoptere-sat-ud-af-spillet)
It doesn't say that anywhere! Where are you getting this from? It says clutch problem which is probably something like the main/accessory drive not being in the engaged state. Not a triple engine failure!

[Sikorsky]

That's one of the issues, that military gives one explanation to the press, but fact is probably different...

[Mustapha Cuppa]

but fact is probably different...

So tell us. What are the facts in this case?

[dangermouse]

so we are probably not getting anything like the full story. No doubt FH are on top of it, the appropriate specialists (none of whom are on this forum) will have the full picture

UK are still flying and I don't believe that any other EH101/AW101 are grounded so this suggests not a fleetwide/design problem

At some point all will be made clear I am sure

anyway congrats to the pilot for getting safely down

DM

[airsound]

Well.... the excellent Flt Lt Ben Wallis (for it was he, in charge) has finally, 31 months later, been handed his well-deserved Air Force Cross by a fellow helo pilot, the Duke of Cambridge, aka Prince William.
https://www.forces.net/services/raf/raf-pilot-awarded-air-forces-highest-honour-outside-combat?utm_source=Forces+Network+Newsletter&utm_campaign=5b0641c034-EMAIL_CAMPAIGN_2018_11_01_06_01&utm_medium=email&utm_term=0_25712c5f6f-5b0641c034-440992797

But, Flt Lt Ben's undoubted courage and expertise aside, what bothers me is how a three-engined helo can suddenly run out of power. To say nothing of the fact that it was at night, and over forest. Anyone care to say what actually went wrong - or, better still, point me towards the Service Inquiry?

airsound

[212man]

or, better still, point me towards the Service Inquiry?

Why would there be an SI into a foreign air force's incident? However, I agree it would be nice to know what happened!

[tottigol]

Danish Merlins were originally RAF owned, there perhaps is the reason why.

[Evalu8ter]

Totti,
Think it was the other way round. We bought 6 Merlins of the Danes in an attempt to respond to the "lack of helicopters" criticism in Afghanistan. We bought the Danes 6 replacement aircraft.

Airsound,
The Merlin is an underpowered / undertransmissioned beast - a circa 11000kg empty aircraft with a max TOW of just 15600kg. At high weights and low airspeed it can be poorly placed…..

None of which detracts from the fact that the lad done good….

[Misformonkey]

Broad spectrum but software problem or fuel to cause a triple ECU failure?

[airsound]

Evalu8ter - I get that At high weights and low airspeed it can be poorly placed….. but surely this event was much worse than that? Something like Misformonkey's "triple ECU failure"?

I imagine current Merliners must be familiar with the story behind this, happily uneventful, event.

airsound

[212man]

I believe it is as caused by freewheel units slipping leading to two engines shutting down through over speed and the third going to an idle power setting due to some FADEC logic.

[SASless]

Some logic... two enigines shutdown and the FADEC puts the last Engine to Idle!

That sounds just a bit odd.

[212man]

Some logic... two enigines shutdown and the FADEC puts the last Engine to Idle!

That sounds just a bit odd.
I don’t disagree!

[Cows getting bigger]

How to make a twin turbine helicopter even more complex. Add a third engine. :)

[dClbydalpha]

I believe it is as caused by freewheel units slipping leading to two engines shutting down through over speed and the third going to an idle power setting due to some FADEC logic.

In my opinion, the FADECs would be responsible for all the engines' behaviour. In this case one of the engines encountered different conditions and so the FADEC responded differently. It shouldn't be inferred that one FADEC behaved in that way due to the other engines.

[212man]

It shouldn't be inferred that one FADEC behaved in that way due to the other engines.

It may be my interpretation of your comments, but you are surely not suggesting that the behaviour was unrelated and coincidental to the other engines' responses to their FWU slippages?

[dClbydalpha]

Some logic... two enigines shutdown and the FADEC puts the last Engine to Idle!

That sounds just a bit odd.

212man, the implication to me of the above, with the subsequent questioning of logic, is that the suggestion is that the last engine was commanded to idle as a result of the other two being shutdown.

My suggestion is that the FADECs responded to what they were seeing at their own engines, and would do so in isolation not as a joint "logic" with the other engines.

[SASless]

So....any idea why in a three engine aircraft....two independent FWU's and an independent FADEC all decide to go Tits Up at the same time?

Inquiring minds wish to know!

[dClbydalpha]

There are 3 engines, "3" FADECs and 3 freewheel units. They are of course linked mechanically. I can see why a FADEC would shut down an engine, or back it to IDLE, as a consequence of a freewheel failure. That is the point I was trying to make, the behaviour of the engines could be consistent with what they were seeing mechanically.

[SASless]

I agree on the two engines that had the Free Wheel failures....seems odd that two would fail at the same time.

The third FADEC should have gone to max power it would seem as its engine was the sole source of power as the other two had gone to idle due to the Free Wheel Units failing.

Why would the last good engine's FADEC go to idle is my question.....along with wondering about the odds of three such "failures" that put the aircraft on the ground with no useable engine power despite having three engines.

[dClbydalpha]

I've assumed that the third engine was at idle deliberately and therefore was also part of the failure events. Rather than it being at idle as a result of the other two engines being shutdown. To me personally that hints at there being a problem with it too.

[SASless]

Or....as it was a training sortie....had the Instructor pulled the one engine back to idle to simulate an engine failure....then the other two engine FWU decide to start slipping and thus begat a real emergency?

The full account is going to make for interesting reading when it is available for consideration.

[Thomas coupling]

Can a merlin driver please confirm the rumour that a EH101 cannot fly on 1 engine

[airsound]

The full account is going to make for interesting reading when it is available for consideration. I do so agree, SASless. Problem is, this incident was two years and eight months ago. I rather suspect that, if we were ever going to hear anything, we would have heard by now.

But I definitely hope that, whatever the problem was, someone knows about it who could do something to make sure it doesn't happen again - and has done just that!

airsound

[pants on fire...]

If ever there was a reason for designing a four-engined helicopter...

[dClbydalpha]

If ever there was a reason for designing a four-engined helicopter...
... possibly resulting in three engines shutdown and one at idle.

[212man]

If ever there was a reason for designing a four-engined helicopter...
Sshhh - AnFi might be watching!

[SASless]

AnFi is probably in a Rest Home having had a nervous breakdown upon reading the post that even mentioned a four engine helicopter.:eek:

[tottigol]

Any count over one probably gives him seizures!:eek:

[Blade Slap]

Can a merlin driver please confirm the rumour that a EH101 cannot fly on 1 engine

It can fly, just with a ROD.

The down-ness depends on PA, OAT, PPI, AUM, IAS and engine rating applied.

[Helicodger Pilot]

It can fly, just with a ROD.

.

The same could be said for virtually anything :}

[TESTburdain]

A Merlin can definitely fly in a 40ft hover with one ECU shut down (because of FOD), one at fly and one increasingly destroying itself due to ice ingestion.
Makes a sound a bit like a Gazelle though.....

[Lonewolf_50]

How to make a twin turbine helicopter even more complex. Add a third engine. :) CH-53E seems to make it work OK. Glad to see the good job recognized. :D

[Thomas coupling]

Amazing white elephant then, as it is now - A £40 million three engined aircraft that only has duplex redundancy.
Which bright spark signed this off?
An aircraft that can't go front line for fear of being shot at because of the cost of trying to repair carbon fibre holes in the field.

[dClbydalpha]

... three engined aircraft that only has duplex redundancy.


Where in the thread or report are you inferring that from?

[Xmit]

Amazing white elephant then, as it is now - A £40 million three engined aircraft that only has duplex redundancy.
Which bright spark signed this off?
An aircraft that can't go front line for fear of being shot at because of the cost of trying to repair carbon fibre holes in the field.

Merlins served operationally in Iraq (UK) and Afghanistan (UK, Italy and Denmark). An RAF Merlin pilot was awarded an DFC while serving in Iraq. That sounds like front line service to me.

[llamaman]

Having flown it, and various other types, in a variety of demanding Operational environments I feel qualified to comment. Yes, it's not going to win a straight 'lift' competition; however, in terms of crash-worthiness it's right up there as well as being the most pilot-friendly helicopter in extremely poor weather that I've had the privilege of being in the cockpit of. For a fast, almost vibration-free poor weather rotary platform with a seriously capable FMS and auto-pilot I rate it extremely highly.