AS350/H125 Hydraulic related accident statistics
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AS350/H125 Hydraulic related accident statistics
Does anyone know if there is a database available that details AS350/H125 hydraulic-related accidents. I'm interested in training incidents as well as the real thing. In particular, if anyone has any knowledge of hydraulic servo runaway or seizure (slider valve seizure) on the AS350 series, that information would be very useful. I'm not interested in servo transparency/jackstall incidents (ie Colin McRae). Thanks. JJ
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In the UK, the AAIB search facility can be used with aircraft type and key-word search
Hi Jelly .... I would guess that almost all of the 350 Hydraulic accidents have been as a result of training !!
it would be so much easier , I would have thought , to just put two systems in there and stop all hyd off training ... then no more write offs !
it would be so much easier , I would have thought , to just put two systems in there and stop all hyd off training ... then no more write offs !
It is a very poor design in my opinion....far too many Pilot Traps in the way the system is controlled and operated.
But then....there's lots of "cheap" about that aircraft type.
But then....there's lots of "cheap" about that aircraft type.
Sas ....not sure I agree with that . The systems are pretty straight forward ( if you are talking about the sequence of cutting off hydraulics for training ) and if you can't get that right maybe you are in the wrong job !!
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From both an engineering point of view and piloting, the Hyd system is simple and robust, and from most of the reports I've managed to locate, a high proportion of the hyd related incidents are training related. I think the biggest "gotcha" has to be lack of knowledge as to "why" we drill the way we do, and the need to consider the yaw compensator. I know from personal experience how easy it is to get behind the aircraft and be tempted to flick the hyds back in, but quickly reminded that this is a bad idea!
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"I know from personal experience how easy it is to get behind the aircraft and be tempted to flick the hyds back in, but quickly reminded that this is a bad idea!"
I'd welcome an explanation of that too. I know the controls suddenly become lighter and can initiate a momentary left roll, but surely it's better to regain control than fight it to the scene of the accident?
I'd welcome an explanation of that too. I know the controls suddenly become lighter and can initiate a momentary left roll, but surely it's better to regain control than fight it to the scene of the accident?
Nigel, If the system on the 350 is so good....why so many accidents both operationally and in training??
Why are we even having this discussion?
How many buttons, switches, levers are involved in controlling system as compared to other aircraft?
The Chinook with two flight control systems had one three way switch.....System 1, Both, System 2 ..... which is typical of most dual system aircraft.
Why are we even having this discussion?
How many buttons, switches, levers are involved in controlling system as compared to other aircraft?
The Chinook with two flight control systems had one three way switch.....System 1, Both, System 2 ..... which is typical of most dual system aircraft.
Last edited by SASless; 14th Oct 2018 at 12:39. Reason: added a missing "we"
It’s all to do with the accumulators . You don’t want to have hyd assistance in one plane without it in the other therefore you have to have them all topped up before you re set to Hyd on ... that works both ways so you cut Hyd off before the are depleted when doing a training exercise . Others can explain better then me but that’s basically how it is . The accumulators give you about three stirs of the cyclic giving you time to come back to around 60-70 knots then they will run out ( but not necessarily at exactly the same time )
I find it difficult to call the hydraulics anything but a human factors nightmare.
sasless being sasless. Cannot take a chance off having a cheap slap on EC. How many of these accident pairs a failure with a pilot error during pre flight check?
And Jim, how many of those belt lost was ignorance during maintenance? Might as well install an anti gravity. Shouldn't we been trained into our muscle instead of read FM at the very moment?
And Jim, how many of those belt lost was ignorance during maintenance? Might as well install an anti gravity. Shouldn't we been trained into our muscle instead of read FM at the very moment?
Care to answer the question about the various controls, knobs, buttons, levers.....etc for the 350's hydraulic system....and say compare and contrast that to a Jet Ranger series or Bolkow/MBB machine?
