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Fatal Crash Broome 4th July 2020

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Fatal Crash Broome 4th July 2020

Old 8th Sep 2020, 18:20
  #101 (permalink)  
 
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Have you ever flown a piston helicopter? On both the Robinson and the Cabri, there are limits associated with manifold pressure, outside air temperature, time and available throttle.
Yes I have - thank you for asking. It didn’t have a governor either. I also learned to fly in variable pitch propellor FW, that also had MAP limits. But that was in an era where I was taught to set RPM by aural cues (then glance at gauge to confirm) and could set pitch and bank angles by looking out of the window (see other thread about how you don’t do this in an AW139 it seems).

Hey - I have seen the YouTube video explaining how the MLI works, and the cockpit displays look great (no dispute) and will reduce workload, but there is no getting away from the fact that the MAP is the FLI.
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Old 8th Sep 2020, 19:45
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A real thread drift going here, so in an effort to continue the direction, having a bunch of hours on the R22 and Cabri, aa777888 has it bang on and I am amazed at the level of (incorrect) vitriol coming his way. Just because a manual MAP lookup can be done (tricky in flight when conditions change), and has worked (most of the time) over the years, does not mean a simple, clear and dynamic display isn’t a better idea for everyone regardless of experience level. I have also flown in conditions (not even particularly unusual) where fuel flow was the limiting factor before MAP - not that I hit the limit, that would be poor form indeed.

Thinking about it, with Nav, I am sure everyone here can use a map, but isn’t a modern moving map display easier all round? Doesn’t mean someone isn’t worthy to fly - that would only be case if they couldn’t fly without a moving map.
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Old 8th Sep 2020, 19:50
  #103 (permalink)  
 
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I think the word ‘ridiculous’ may have got people’s attention. Got mine.
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Old 8th Sep 2020, 19:58
  #104 (permalink)  
 
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So for the number of landings and take offs you are likely to do in a sortie, working out the MAP limits is too difficult and demanding and requires a digital display? How many of you are taking off and landing at vastly differing density altitudes on a regular basis in a Robbie?

Proper Pre flight Planning Prevents Piss Poor Performance - 7 Ps of aviation.

Cabri are obviously superior to Robbies if the MLI is so good.

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Old 8th Sep 2020, 20:40
  #105 (permalink)  
 
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Quite often in California actually, where I take off at 400', may eventually climb to 6000' en route due to mountains, and land at perhaps 2500' (Las Vegas) while temperatures are all over the place, cooler near the coast and very hot over the desert.
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Old 8th Sep 2020, 21:09
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I see lots of temperature variations when operating between sea level and 3 or 4 thousand feet (rarely get above that around here), or on a cross country that starts in the cool early morning then you start to see the heat of the day, or from inland to the shore or vice versa, etc., etc. Nobody said it was hard to manage, or do, or whatever, just that it would be easier and possibly safer if a machine did it for you. Just like it is on a turbine. And don't forget the throttle limit factor, hence an MP gauge cannot be an FLI, it does not account for that, even if you are willing to give it a pass as an FLI because you looked up the exact MP limits vs. temperature for that particular moment in time. And being able to understand your available throttle is a nice safety improvement.

Obvious troll, crab, no bite...
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Old 9th Sep 2020, 06:38
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aa777888 - as others point out, MAP limits are only a real issue when taking off and landing - are you doing that at varying alts and temps or just cruising through?

The throttle limit is pretty obvious because if you keep pulling the Nr goes down.

Didn't think you'd want to admit to Cabri superiority

CCGame - If you don't know what the likely conditions are at your intended LS (you only need a phone to find out) what pre-flight planning are you doing? The conditions in Vegas are very predictable so not much thinking required.

You could have a copy of the MAP placard on your kneepad or even on the ubiquitous I-pad so why crane your neck?

How many owners would pay the extra on a Robbie for an MLI? And are they pestering Robinson to provide one?

Seems like a problem that doesn't need a solution, just a bit of planning required.
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Old 9th Sep 2020, 07:48
  #108 (permalink)  
 
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Originally Posted by [email protected] View Post
Seems like a problem that doesn't need a solution, just a bit of planning required.
Indeed.
Who spends their time staring at a panel or waiting for a caution to light so you can work out you are near a limit.
In the 2 hours or so that these aircraft can manage to fly, density conditions can only change so much.
You plan performance and loading for the highest and warmest condition in flight.
After that, fly with some accuracy, preferably into wind and the aircraft will perform as expected.

When the lever meets the armpit, an exceedance approaches.


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Old 9th Sep 2020, 10:50
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Originally Posted by Robbo Jock View Post
Wonder if the TR flex coupling let go, that could have created an effective little circular saw inside the tailboom which would explain the fairly neat cut.
I would think they could do metallurgy tests on the pieces and get pretty close to finding out what gave way first. Not sure if they will do that though.
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Old 9th Sep 2020, 15:19
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Originally Posted by [email protected] View Post
aa777888 - as others point out, MAP limits are only a real issue when taking off and landing - are you doing that at varying alts and temps or just cruising through?
Most of my flights lately are cross country. Interestingly, those are the flights that have peaked my interest in having an MLI or FLI even though it's a piston single. The quick hops are, as you say, not an issue, just figure stuff out for takeoff and landing. But I find when I am trying to make time and run MCP the entire way I keep a critical eye on things. For me it's not unusual to see a OATs variation of 10-20 degrees during cruise on a cross country flight, and elevation changes of 3000 feet or so. It's not just flat, boring terrain around here, it's mountains and seashores and everything in between. Yeah, it's only a difference of an inch or so on the MP limit, but again, it's a want, not a need, and electronic engine instrumentation is less expensive than separate gauges so why not? Bruno liked the idea, obviously, and I know you are all fans of Bruno!

The throttle limit is pretty obvious because if you keep pulling the Nr goes down.
Now you are just being silly.



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Old 9th Sep 2020, 16:32
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Map limits don't change drastically in flight but they do change; in my last flight there were times during cruise when MCP was 23+" and other times when it was 21". More relevantly though, Vne changed dramatically, from 130 kts at departure down to 103 kts when going over a mountain at high temperatures. I would absolutely pay extra for something that makes this easier to manage. I may even write my own Android app to show the current map/Vne limits, though I don't know how to feed it OAT so that may have to be selected onscreen (simple slider).

The ideal solution would be for the Garmin PFD to be programmed to change its yellow/red IAS arc dynamically based on conditions, because it does know OAT and altitude. (Pilot would have to remember the 2200 lb thing.)
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Old 9th Sep 2020, 16:53
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And yet the green arc ends at 110kts IAS and the poh warns against anything above unless in smooth air..
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Old 9th Sep 2020, 18:43
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Now you are just being silly.
Why? Do you believe that doesn't happen?
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Old 9th Sep 2020, 21:18
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Originally Posted by [email protected] View Post
Why? Do you believe that doesn't happen?
Trying to avoid getting roped into this debate, but I believe he's implying it's nicer to have an EFIS tell you how are you are from full throttle (and when you've reached it) so that by the time your Nr is drooping, you're aware of it and making control actions based on that information. I think if the only thing alerting you to the loss of Nr is the warning horn, you're probably stuffed by then. As many have said before, the MAP gauge is sufficient for defining limits, but I'll agree with 'a(whatever the username is)' in saying that the MLI of the Cabri makes it much clearer to the pilot what your limit is and how far from it you are. My 2 cents worth; having a 0-100% gauge on a Robbie might just help the not-so-stellar pilots among us to realise when they're testing the limits of the aircraft and encourage them to calm down - especially the casual pilots who don't necessarily do all the pre-flight planning we all take for granted.

That being said, this is all a massive thread drift from the OP (a fatal crash presumably caused by TR anomalies), so I hope the 'proving people right on the internet' debate can subside to keep this thread relevant.

P.s. The Cabri is better.
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Old 9th Sep 2020, 23:21
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Shirley somebody would be smart enough to modify the MAP gauge to have a temperature and a pressure altitude input, which moves the outer scale (0 - 100%) so that with altitude / temp increase, the 100% part of the scale moves anti-clockwise towards the needle.

And don't call me Shirley.
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Old 10th Sep 2020, 03:44
  #116 (permalink)  
 
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Originally Posted by Ascend Charlie View Post
Shirley somebody would be smart enough to modify the MAP gauge to have a temperature and a pressure altitude input, which moves the outer scale (0 - 100%) so that with altitude / temp increase, the 100% part of the scale moves anti-clockwise towards the needle.

And don't call me Shirley.
Sadly that would require technology available to us decades old to be put into production.
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Old 10th Sep 2020, 05:50
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ApolloHeli - I remember an important part of my R22 conversion was demonstrating the ability to recognise and recover from overpitching (ie rasing the lever past the point of max fuel available). You can't miss the sound of the Nr decaying even before the unfeasibly loud horn goes off.

This should be a basic skill for a SE piston heli pilot.
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Old 10th Sep 2020, 15:11
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I could add to the thread drift, or simply point out that lack of power, or the finer points of where the “flight manual limit” was on the day in question, almost certainly did not contribute to the crash in question.

Pax on a mtce test flight would seem to have contributed to the fatalities and serious injuries.
The failure seems to be atypical and as yet unexplained.
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Old 10th Sep 2020, 16:43
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Originally Posted by Twist & Shout View Post
I could add to the thread drift, or simply point out that lack of power, or the finer points of where the “flight manual limit” was on the day in question, almost certainly did not contribute to the crash in question.

Pax on a mtce test flight would seem to have contributed to the fatalities and serious injuries.
The failure seems to be atypical and as yet unexplained.
Thank you.

Cheers,
Grog
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Old 13th Nov 2020, 09:04
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I have been following this thread and other's for some time now. and I, like other's here are interested to see the final ATSB report into what happened in flight.

Let me 1st introduce myself as an A.M.E
Several members here have already mentioned drive shaft damper bearing failure, flex plates cracked RB's etc etc. I am not an accident investigator by any means, however after several R22 and R44 rebuilds and 100 hourly inspections on R22 and R44's being operated in desert country (red dirt, mustering environments) I have come across many times over the years that there has been excessive wear associated with the C121-17 push pull tube connecting to the A120-3 Bellcrank Assembly on the TRGB, has excessive wear from dirt build up between the C121-17 Push pull tube and nylon guides within the tail cone.

The aircraft in question was only operated out of the industrial estate where the incident occurred. Never from bitumen or asphalt helipad as per the ATSB investigation. The aircraft would have spent it's life cycle ingesting dust and dirt each time it left or returned to it's home base. No doubt dust and debris was ingested into the tail cone and associated empennage for some time and probably since aircraft in question was sold in this country. I have seen wear on the C121-17 on many R22 and R44's which are based on the many cattle properties through out this country where the dirt build up between the nylon bushes has worn deep into the push pull rod and required replacement or renewed paint to be applied to effected areas.

To me, it looks as though the push pull tube has worn through which would not have been detected with a ground run and TR balance. The push pull tube has given way causing the TR to swing at an angle which resulted in complete loss of control and the TR blade to cut through the tail cone assembly resulting in the fatal incident currently under investigation.

Anyone who works on R22's or R44's which spend their lives mustering or in dirt\dust would have encounted the wear produced on the C121-17 tube from dirt build up between the nylon bushing.

IN MOST CASES I HAVE EXPERIENCED, THE PUSH PULL TUBE HAS NEEDED TO BE REMOVED TO FULLY INSPECT FOR WEAR BETWEEN THE NYLON BUSHINGS.

My reference book is the R44 IPC found here: R44 IPC - Robinson site *unable to post links until I have reached 10 posts"
65.0 - Item 8
C041-1 Damper Assembly

65.6 - Number 19
C121-17

67.90
C121-17 Push pull tube.

Anyone else able to shed some light on their experiences when removing the C121-17 on mustering choppers?

Cheers

Winfield.

Last edited by Winfield83; 13th Nov 2020 at 19:18.
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