R44 Loss Of Engine Power

[milehigh]

I was flying an R44 yesterday with 3 passengers on board up onto a mountain side.

On approach to the LZ i checked my Ts & Ps and noticed the CHT was reading slightly lower than normal, I thought that is odd considering the resonable climb id just had, I took a mental note to keep an eye on it for the rest of the day and suspected guage failure as everything else looked fine.

As I flew past observing the LZ on the side of this very steep mountain at 4,500 ft my low RPM horn came on, I observed both rotor and engine rpm decay. From here everything happened very quickly and with the ledge now down wind and behind me as the only possible landing spot ( cliffs all around it ) I only had time to react. I turned down wind lowering collective a little with the throttle wound hard open, initiated the flare observing 80% rotor and Engine RPM before applying FULL collective, I overshot the little cleared square buy half a skid length and was perched awkwardly in the tundra. But over all and ironiclly I have had rougher landings.

I then lowered collective with throttle still open and the engine slowly wound back up to the green, it was running seriously rough so I performed a mag check as I've had numerous mag failures ( not nearly as dramatic as this was! ) they checked out fine temps and pressures were all ok except CHT reading nothing, again I suspected gauge failure as I've had that previously so I tried picking it up into an inground effect hover, perhaps shouldn't have but I really wanted to know what was going on and how I had ended up merely inches from meeting my creator!, 25 inches of manifold pressure and hardly light on the skids and once again low rpm horn.

So I shut it down, called for an engineer and another helicopter for my passengers.

 

I returned today with engineers and they discovered the front left cylinder which is the cylinder that the CHT probe is connected too had an injector that was completely blocked by a peice of thread tape ( thread tape is not allowed to be used on these engines! ) an investigation into our maintainence company will follow...

 

I do not wish to disclose my name, country, company or location.

I have been flying for 10 years, mainly Astars, this was only my third flight in the 44 after a year away from them as this machine was straight off a full overhaul.

Hopefully I don't get ripped to shreds for my story, there is a few people on here that appear to always know better and hind sight is always a usefull thing! When your *** is on the line you do what you have to, hopefully by instinct because there is not time for anything else!

 

I hope this story is useful to someone out there.

 

In the Robbies defence ( although I'm not their greatest fan, I have done a fair amount of flying in them ) had I been in an Astar in a comparable situation I think I would have fallen short and ended up in a tangled mess somewhere way down the mountain side.

 

Very greatfull to still be alive but am struggling with the idea of continuing forward with this career, our job is hard enough, sometimes feels like the world is against us but when your helicopter turns against you too what do you have left, maybe just the wife and kids at home worring about you!?????

[Freewheel]

Sounds like a crappy day for sure! Keep your chin up and remember you did a great job with a bad situation; although your aircraft let you down, it still got you back to planet earth (along with your training). My advice, don't overthink it. It's always tough to move on after something like that, but you can't be second guessing yourself (or your aircraft) on future flights if you chose to stick with this crazy career....

[Freewheel]

Don't forget to give yourself a pat on the back!

[R0T0R]

Well done! No judgement should be made unless you've been in a similar situation. In a situation like that, who cares about the machine, I'm glad you and your passengers are safe.

 

R

[Heliian]

The blockage may have been there for some time, now that you were at altitude and heavy and demanding max flow, the injector could not keep up. You say it just came from overhaul so I can guess they did the bladder fuel tank upgrade which is a whole pile of new fuel system parts, which could be the culprit.

 

Please don't compare these a/c with a turbine workhorse as they were never intended to be used commercially or for any longevity.

[Helilog56]

Milehigh....you did a good job in what was a bad situation that could have been way worse. Thanks for posting the story....it is always nice to learn something out of these situations.

What I take from this is a couple of things.....first never assume the gauge is wrong, and secondly check that power well before committing to the approach to land....during the climb is a stellar time to pull max power when you have achieved your density altitude....

[Helilog56]

Heliian.....I've seen and flown R44's long enough to disagree with your assessment.....there a literally thousands of them out there working in some of the harshest environments globally. They have accomplished thousands and thousands of flight hours, thousands of auto rotations and worked hard in a training environment, I have a huge respect for how they preform in the mountains with high DA numbers, I've done vertical reference work with them, flown in high and turbulent winds, etc, etc.

 

Very sound and reliable aircraft from what I've seen.....don't remember ever reading a limitation stating "not for commercial use or long term reliability"....???!?!?

[skullcap]

Sounds like you made out well! Good job!

 

You obviously now do not feel so good about trusting the aircraft or any for that matter, so to go forward what can you do? Stack the odds in your favour a little more as Helilog said. Also, to me it sounds like you were going into a cirque with your description of cliffs all around and then to make the 180 to lz. So, with cirques, I always try to make my first pass outbound out of the cirque, have had huge scares in functioning piston bangers let alone a sick one. Monitor that manifold pressure and ensure that with the power applied that the aircraft is resondiing, if not is downflow or bad power. Keep chin up and just take it one step at a time.

[milehigh]

Thanks for the encouragement folks.

 

This was the second flight with passengers after the aircraft had been on the ground for over a year being rebuilt, I did only 0.2 of the all the test flying that was done and then this was the second flight with passengers of which I had piloted both.

I do wonder if there had been a loss of power from the start but power checks had indicated normal.

 

For the conversations sake this LZ is a knoll or flat ledge if you like that juts out the side of a large range of mountains, three sides are not connected to the mountain and are vertical cliffs that drop down 50 - 200m depending which side. I could have autoed to the bottom, problem is there is nothing there other than really steep faces and then a lake with no shore.

 

As Helilog56 said I will never assume a gauge is reading wrong again even if I don't understand the reading it should be taken as serious gospel until proven otherwise!

Also agree with your comment re the R44, I have done a wide variety of work in a 44 and as I say not my favourite machine but in its defence I'm not the best pilot in the world and had I been in any of the other 9 helicopter types I have flown in a comparable situation I would not have made it to the safety of this small flat ledge and would have been down the mountainside somewhere!?

 

This LZ was the only suitable emergency landing spot regardless of what happened and my power check on and up until my pass by to ***** wind etc had indicated enough power for the job, and then it hit me right at a spot I would have said that I would not be able to make it onto the LZ. Thank God I did!

 

Everyone have a safe day

[milehigh]

Just to clarify the landing site a little more, not sure if my description was accurate enough, it is the opposite to a cirque its a piece of land that sticks out into thin air supported by substantial cliffs on three sides with a slope that continues upward on the uphill side so you can fly of three sides of it and have over 3000ft of air under you with limited or no places to auto to.

 

I passed it on the uphill side into a slight breeze for my reece with any option available to me, loss of power took place as the LZ was back over my right shoulder. Right pedal, lower collective while Driving back there with the Cyclic into what had to be a shallow hard flare with very limited RPM left at the bottom.

 

Clear skies & High rpm to you all Im heading off flying again, wish me luck!...