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As350 Problems?


Hoss

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Excellent posting Skullcap.

 

Something is happening in these HYD failures. It just shouldn't be a big issue to fly an Astar with HYD off, we have all trained with the system off in the past, with favorable results.

The question is why does an highly experienced OMNR pilot loose control and go in inverted?

Why does a Native air Pilot loose control and wreck a B3 on the Mesa AZ airport?

Why did this latest pilot have difficulties? If it was CHC, their recurrent training is second to none.

 

What is going on? What in this HYD system is causing experienced pilots to loose control ?????

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Here here 407...I ask the same question as a new 350 driver. Why after 25 odd years is a system on this ship killing people? Is it the same ol' system on the same airframe with more powerful plants? Something stupid is causing this and it is time France answers to the call. And Maggie....stop taking offence by'...I don't think anyone is pointing the finger at you. Oh, by the way, when I show up in March for the equipment install, get your ar$e front and center so we can meet and greet!! :D

 

LR

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Skullcap, you obviously have access to the CHL incident report, given the quotes you've made. That being the case, you must also know the history of these occurrences. What, exactly, would you propose the Minister to do? We have four dead folks from a year ago, with eye-witness and electronic proof that they went in the 'wrong way', two more ground incidents, and now another flight incident of uncontrollable cyclic forces during hydraulics off flight. I don't know what is going on any more than you do, but there is obviously a failure mode in this aircraft that results in control forces that are unmanageable by the pilot. That is not acceptable.

 

Remember, it is TC's mandate to protect the public, and that's what they are doing in light of an unexplained phenomenon.

 

I have to be very careful what I say here for obvious reasons, but I have very dear friends flying this aircarft right now, and I don't like it.

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Being an Astar pilot I've been thinking about this allot. It seems to me that this may not a hydraulic problem. All of the real problems have come about once the hydraulics has been shut off.

Could it be that the initial indication of hydraulic difficulty is transparency, caused by excessive aerodynamic forces? Then the hydraulic system that is already to its max is cut out of the picture. Now you have a pilot truly with his hands full.

This last incident has the hydraulic system cut off at the collective, I assume. The forces, now only aerodynamic, are the issue.

Am I wrong?

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I wonder if a slipping belt could be the culprit. If you look at a how far down, rpm wise,a pilot can move the controls with hydraulic assist,down to probably 20 rpm on run down. it would seem pressure is sufficient. there is no tension check mentioned on inspections,ie,2 mm deflection at 2 kg load.The 500 cooler belt uses such a check.The astar check usually consists of listening to the twang the belt makes. I saw a peice on TV,with the gates belt rep saying how the company hated seeing people not using a tension tool to put belts on,especially timing belts, if they came out with a weight on an arm tool and a torque check to see if the belt slips, then we can eliminate belt slippage.then look at the fluid, is any other A/C having problems with 5606?I haven't heard of any..

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I have had to fix hydraulic problems on Eurocopter and Bell helicopters.

Instead of fixating on the A-star's hydraulic systems engineering maybe the incidents were caused by other factors like poor overhauls, maintenance errors, or poor snag communication between pilots and engineers. Leaky servos, dirty pilot valves, improper flight control rigging, moisture in the hydraulic fluid, mixing of hydraulic fluids, weak/discharged accumilators, worn rod ends, poorly routed hoses (causing binding), induced collective bounce, improper cyclic/collective friction, improper servo shimming, faulty hydraulic manifolds/switches, broken wires, poor grounding, lack of caution light indication when malfunction arises, and numerous other problems affect the hydaulic sytems of all helicopters. I think Transport Canada's reaction to the hydraulic issue on the A-Star is unfortunate and I think they should have had a definite cause pin-pointed before issueing such a vague AD. If Transport Canada is setting a precedent and reacting to all accidents/incidents this way it will negatively affect our industry as a whole. I believe thorough investigation of all incidents/accidents is the answer and jumping to unfounded conclusions is not.

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well this is a very dear topic to a lot of us. like 4961, both myself and the other pilot in the office think that it may be something other then the hyd sys. the fact that it rolls left and not to the right and back seems to be a key point. also have done some checking with sources, and the other thing that keeps showing up here in canada is the fact that all 4 have been in cold weather. as 407 states that was not the case down south. astars having been flying for lots of years and now just in the past two, things are showing up. wonder if there has been some mods, or change in who building the parts that could be causing the problems to show. we are down at this time for a 500 and are doing the mod on the belt drive. maybe the new ad will be the ec-130 mod, two syss, one run off the new belt sys and one off the gear driven pump. could cost alot of money. last thing, i think that if we are still allowed to keep them flying then we should also be allowed to do the hyd training. if the belt breaks this will be a good thing to have, slow down 40-60 kts and get ready for a nice run on landing. if it is something else with the hyd or rotor sys, its not going to make any differance. lets hope that eurcopter and tranport can have a good look at the last aircraft and see if something shows up in the system or how it was rigged.

have a great night and a safe week flying.

longranger, i did not see you add that you wanted your 206L back....

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