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Hydraulics failure- helicopters

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Hydraulics failure- helicopters

Old 12th Oct 2018, 09:00
  #21 (permalink)  
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Thanks for the replies and details. Interesting to hear
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Old 12th Oct 2018, 11:35
  #22 (permalink)  
 
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Many years ago, a 206B on short finals to land on a dock-side when suddenly cyclic and collective go stiff. Pilot managed a decent landing and all was well. Investigation revealed that one (I don't remember which) of the hydraulic system quick-disconnect fittings had not been connected properly and became completely undone, probably through vibration. Simply reconnected properly and all as well..
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Old 12th Oct 2018, 16:20
  #23 (permalink)  
 
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The investigation is still on-going---will post more when I can.
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Old 12th Oct 2018, 17:50
  #24 (permalink)  
 
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Wires are very hard to see no matter how careful you are.

While Cherry Drying in Washington State....I would always do a Recon (Recce) of the field before I flew in it blowing the water off the Cherry Trees.

Despite that....one afternoon with the Sun in the wrong direction....I came scary close to cutting down a set of wires going to a water pump house.

A few days later....two other aircraft hit wires....one being a Fatality.

If you have done utility or ag work with a Helicopter for any length of time.....you probably have had a close call or two with wires.
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Old 12th Oct 2018, 19:51
  #25 (permalink)  
 
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Had a Hyd failure in a 206. Leak which made it much harder to fly vs a pump fail. (pull the hyd CB to make sure it is not just a switch failure...pulling the CB will restore pressure if it is an electrical problem.)

Had 2 in a Astar. First order of business.. turn off that +*^% horn so you can think.
205...,remember that you should never lower the collective below 35 PSI because it will be a bitch to pull it back up.
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Old 12th Oct 2018, 20:18
  #26 (permalink)  

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Failure of the collective pitch boost system on a Blackhawk can result in a very heavy collective. IIRC, it can push up with the equivalent force of 80lbs of weight. It was certainly enough to lift me out of my seat, even with the leg straps done as tight as I could bear them, it's really a two pilot job to fly it in that condition.
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Old 12th Oct 2018, 20:24
  #27 (permalink)  
 
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105's and 117's are a delight when it comes to Hydraulic Failures!

Even Cook Book pilots can handle hydraulic failures in them.
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Old 13th Oct 2018, 00:00
  #28 (permalink)  
 
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Angry

Had a Hydraulic Failure in a JetBox.......scary on take-off from a pinnacle, but quiet manageable Also in a B2 Squirrel.......F.F.F.F damn serious when You only have fuel to go back to the marginal confined H & Your heavy
Practise, practise, practise & have a plan is the secret to success
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Old 13th Oct 2018, 08:55
  #29 (permalink)  
 
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Last year we had a creeping failure on our 206. You could feel it starting to fail. If you moved the controls fast you would feel resistance. If you moved them slowly you maintained pressure. The problem was that after we had changed various components we thought we had fixed it. But no. It would come out of nowhere. Nothing quite like a hydraulic failure coming off or landing on our mix truck for ag work. We finally ended up changing out the quick release couplings and that cured the problem.

None of the above is written in the flight manual either......

As for wires. Had a few close calls, but so far have not hit any.
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Old 13th Oct 2018, 10:20
  #30 (permalink)  
 
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Canít think of many people I would rather be in an emergency than Tim Price ... he probably has more experience in real flying than most here so ignore him at your peril ! ( I am sure there are exceptions to the rule book on special operations but the pilots doing those generally know what they are doing . Most here are just Sunday vfr flyers and donít need to be told to ignore their flight manual )
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Old 13th Oct 2018, 13:22
  #31 (permalink)  
 
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Nigel, You do understand most RFM's are written by Lawyers with some input from Engineers and Test Piots?

RFM's by necessity are a one size fits all approach with its main focus being relieving the Manufacturer from liability.

As most Regulations and RFM's are not etched in Stone....Training has to fit reality and there is not a RFM out there that can accomplish that.

Mr. Price may be very experienced and perhaps meant something different than the way his post came across.

That being said.... training must take into consideration what the RFM has to say about Emergency Procedures but if those procedures do not fit your operation then what do you do?
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Old 13th Oct 2018, 14:18
  #32 (permalink)  

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I was flying in echelon starboard formation with another Puma when the sky a few metres ahead of us suddenly turned bright red!
When hydraulic fluid mist sprayed all over our windscreen I realised what was happening and called on the radio: "Two to Lead, Looks like you've got a major hydraulic failure!"

Reply: "Negative, everything's normal here.....Oo - er! PAN PAN PAN!"

Twenty seconds later he was parked in a field.
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Old 13th Oct 2018, 15:52
  #33 (permalink)  
 
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Only he can say , but I think he was saying go with what it says in the manual .... donít try to wing it and come up with your own idea on the hoof !!!
obviously it is not a one size fits all but for over 90% of pilots and the flying they are doing it will be correct . Are you saying that all that flying by test pilots coming up with the correct actions are not correct and you know better ??? Again I have to repeat myself because many on here just like to show off their skills .....,I am not talking about mountain sites with no flat ground to land on ....Iím not talking about flying sling load over dense forestry . The pilots reading this do not need encouraging to ďtry out ď what worked for you 20 years ago flying drilling rigs !!! In those circumstances I can well see instructors / high time pilots making their own plan for an emergency.
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Old 13th Oct 2018, 16:20
  #34 (permalink)  
 
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Now you are being obtuse.

Everyone of us has said training must be done with actual tasks in mind and that the RFM does not always lend itself to those situations.

No one has said "ignore" the RFM.

What we have said is you have to tailor your procedures to fit the need.

If you think any RFM is sacrosanct then why are there Amendments and changes to them over time?

As you note in your own post....not every situation is the same.

If the RFM fits what you are doing....of course you can follow its procedures.

What do you do when there is no Emergency Procedure for the malfunction you are experiencing.....don't you have to come up with a way to cope with that?

Pick a topic....say Tail Rotor Malfunctions and layout all the possible situations.....how thick would the RFM Emergency Procedures Section be if they tried to address each variation of the range of failures possible?

That is why I endorse the notion that the RFM is the guide....not the law.

Are there variations within the RFM as approved by different Authorities?
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Old 13th Oct 2018, 16:58
  #35 (permalink)  
 
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It was this remark .....

I do so love "Cook Book " Pilots....who must lead a very sheltered existence.... that I objected to . Firstly you probably have no idea of what he does and what his experience is and lastly you just sound arrogant referring to most of the pilots here as ď Cook Book ď Pilots .
A tiny bit of humility wouldnít hurt .
of course I agree that the book doesnít cover everything......

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Old 13th Oct 2018, 18:04
  #36 (permalink)  
 
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Merely responding to his post.

I did not address my comment to him personally or to "most" the pilots attending this forum.

There are "Cook Book Pilots" out there.....not only in our Industry but throughout all aviation beginning shortly after Man began to fly.

The accident records are full of examples.
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Old 13th Oct 2018, 18:04
  #37 (permalink)  
 
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To tailor a response or reaction to something new, requires experience.
if you have no experience your best bet is to follow a procedure written by someone who had that experience. Hence why flight manuals were created.
they can become legally binding in situations. Dont believe me, go toe to toe with an ornery prosecutor who is holding your actions up to a published and approved procedure.
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Old 13th Oct 2018, 19:12
  #38 (permalink)  
 
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Ornery Lawyers is why RFM's are written the way there are to a great extent.

But bear in mind....the FAA understands why deviations from the FAR's (which incorporate the RFM) and for Commercial Operators, FAA OPSPECS), are up to the discretion of the Pilot-in-Command during emergencies.

https://www.law.cornell.edu/cfr/text/14/91.3
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Old 22nd Oct 2018, 14:49
  #39 (permalink)  
 
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re: hydraulic failures... I'm glad this was brought up. My question isn't about losing boost - I spend so much time teaching loss of boost that it really doesn't worry me (but I don't fly anything larger than a Bell L3 so I might think differently if I was flying bigger aircraft). [btw, Frank Robinson once told me that feedback forces go up as the cube of the blade chord. yikes!].

My question, that I've asked about 10,000 people is, does anyone know anyone who's had a hard-over, i.e. where one of the servos malfunctions and goes full stroke in one direction or the other? Nobody has ever responded in the positive, so either it just doesn't happen, or everybody it's happened to is dead. Anyone here have any input? I usually tell people (half jokingly) that if it happens, the first thing you do is turn of the hydraulics, and the second thing you do is recover from inverted flight.

Can anyone comment from first or second hand experience? I'm assuming nobody is strong enough to fight a servo and that the stick is simply going to go full deflection in some direction, depending on which servo has had the failure?
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Old 22nd Oct 2018, 15:07
  #40 (permalink)  

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Some helicopters simply can't be controlled without hydraulics, which is why larger helicopters have two separate hydraulic systems.
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