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Sheer Bad Luck

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Sheer Bad Luck

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Old 8th Jun 2018, 12:21
  #41 (permalink)  
 
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Chop ... I would stop digging !!!
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Old 8th Jun 2018, 15:08
  #42 (permalink)  
 
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Stop digging? Hellfire Man....he done went out and bought himself a Mechanical Excavator to speed up the process!
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Old 9th Jun 2018, 21:29
  #43 (permalink)  
 
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Chop - you sad f•Äer. I've told you before haven't i?
If you want to play in here with the pro's then act like one.
You're setting a bad example to newbie's and abbo's listening in.
stop showing your ignorance in public!

Excess weight causes excess strain on the drive train.
Excess weight stresses the airframe.
Excess weight affects your RoC and your RoD.
Excess weight affects your stall speed and Vmax
Excess weight alters your C of G.

ALL of the above Exceed that aircrafts limits for optimum performance which is why THERE IS A FUC**ING LIMIT TO THE MTOM.

Please behave in future..........
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Old 9th Jun 2018, 22:07
  #44 (permalink)  
 
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TC
Excess weight causes excess strain on the drive train.
Not if you don't pull the torque / tot out of the green arcs.
Excess weight stresses the airframe.
Not if you don't pull the torque / tot out of the green arcs.
Excess weight affects your RoC and your RoD.
Obviously, like I've been saying all along, but if you stay in the green arcs and trade ROC for the extra weight all is well.
Excess weight affects your stall speed and Vmax
Stall speed? But if you stay in the green arcs and trade performance for the extra weight all is well.
Excess weight alters your C of G.
That depends where you put it, so if you do a weight and balance calculation and remain within the moment limits...
Please behave in future..........
Of course, LOL.

You can also over stress everything at less than MTOM by pulling too much pitch... (If you have the power!).

Last edited by chopjock; 9th Jun 2018 at 23:00.
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Old 9th Jun 2018, 22:30
  #45 (permalink)  
 
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🙈......I hate to be on the same side as TC .... but really ???? Overload a car and you f**k it up eventually and the same goes for a Helicoper but the consequences can be much worse and probably with someone else flying !! We ALL know you can fly perfectly well , with deft handling , well over max weight . I did it on occasions crop spraying but it comes at a cost and should not be encouraged or condoned . If you want to carry more .... put your hand in your pocket and buy a more powerful Helicopter .... donít endanger the lives of future passengers !!
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Old 10th Jun 2018, 00:42
  #46 (permalink)  
 
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Chopjock,

Explain to us all here what excessive weight does for Coning Angle, Angle of Attack, and Stress Loading on the Blades, and attached bits right down to the Transmission mounts will you?


In support of TC in this....I would never fly an aircraft after ChopJock did....ever!

Your attitude and knowledge or lack of....is very dangerous to others.
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Old 10th Jun 2018, 03:23
  #47 (permalink)  
 
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Chopjock, your profile says you are a PPL(H) and an engineer with over 2000 hours. Please post a picture of you PPL, engineers lic and last page of your log book. Because from the stupid things you say I cannot believe that you are any of these.

If you are an engineer, then you would know, that by hanging more weight under the rotor system you would increase the stress on the rotor shaft and the bearings that stop this shaft from being pulled out of the gearbox. Plus the gearbox mounts and a whole lot of other stuff that I wont go into, just trying to keep it simple for you!

I don't know you so I am trying to give you the benefit of doubt but as you are getting on a bit perhaps you should get a check up for dementia because it is either that or you are a troll. No one that is sane and with the qualifications that you profess, could possibly say the things that you do. Some of the things you say would be funny, except that there are inexperienced people that come on here to learn.

I look forward to seeing your doc's.
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Old 10th Jun 2018, 07:06
  #48 (permalink)  
 
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So Choppy - you overload the aircraft and manage to stagger to the hover (at the very top of the green arcs as you love to insist) - what spare performance have you got to transition?

You may have a 5 min takeoff rating but you are extremely likely to be eating in to that just hovering.

Suppose you do stagger into forward flight and need to climb - have you accounted for your large decrease in climb performance, your reduced VNE (which graph are you going to use for that since you are above MTOM?)

If you have an engine failure, have you thought about how the remianing donkey is going to cope with that excess weight?

If you don't think that just hovering at above MTOM is stressing the aircraft - high torque/T4,more TR thrust and strain on the transmission - then you aren't an engineer.

Your assertion that there is no difference between MTOM and above MTOM ignores the fact that you are very unlikely to be able to do this 'in the green arcs'.
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Old 10th Jun 2018, 08:54
  #49 (permalink)  
 
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"That depends where you put it, so if you do a weight and balance calculation and remain within the moment limits..."

Chop
Assuming you are familiar with weight & balance calculations... the moment limits are defined in the weight & balance part of the RFM imitations. They can change depending on the AUM, but above the max AUM and below the min AUM, there are no moment limits defined !

Also not mentioned earlier on the thread - the undercarriage can also be a limiting factor for AUM. Too heavy, and your gear/skids may collapse if and when required!
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Old 10th Jun 2018, 08:56
  #50 (permalink)  
 
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Lovely response chaps...
SAS
Explain to us all here what excessive weight does for Coning Angle, Angle of Attack, and Stress Loading on the Blades, and attached bits right down to the Transmission mounts will you?
If you stay in the green arcs, excessive weight will do the same as normal weight. (The rotors are only pulling up at the same allowable rate, so coning angle etc is the same but with a much lower ROC if any).
In support of TC in this....I would never fly an aircraft after ChopJock did....ever!
That's ok, but I never take off over weight and always remain within the green arcs...

bront
If you are an engineer, then you would know, that by hanging more weight under the rotor system you would increase the stress on the rotor shaft and the bearings that stop this shaft from being pulled out of the gearbox. Plus the gearbox mounts and a whole lot of other stuff that I wont go into, just trying to keep it simple for you!
If you are a pilot, you should know that adding more weight under the rotor system is balanced by the amount of thrust produced by that rotor system. If you only produce up to max allowable thrust (remain in the green) then there is NO MORE added stress! Your statement would be true if I added excess weight then tried to climb at the same ROC achieved with the lighter weight.
Some of the things you say would be funny, except that there are inexperienced people that come on here to learn.
I'm sure inexperienced people will read all the posts and make up their own mind, I am sometimes just giving a different point of view for the sake of discussion and it's working!
crab
you overload the aircraft and manage to stagger to the hover (at the very top of the green arcs as you love to insist) - what spare performance have you got to transition?
Probably none so if you can't do it within the yellow arcs and within the time limits, put it back down.
Suppose you do stagger into forward flight and need to climb - have you accounted for your large decrease in climb performance, your reduced VNE (which graph are you going to use for that since you are above MTOM?)
Yes, not sure a reduced VNE would be relevant as if you are over weight you would be using up to MCP and being a pilot, one would expect to fly gently within the normal cruise at all times anyway!
If you have an engine failure, have you thought about how the remianing donkey is going to cope with that excess weight?
No, you've got me there, I am assuming no mechanical failures during the over weight part of the flight. (After all, are you likely to have a failure if you remain in the green?)
Your assertion that there is no difference between MTOM and above MTOM ignores the fact that you are very unlikely to be able to do this 'in the green arcs'.
Yes absolutely correct. But, if it's a cold morning at sea level...

Last edited by chopjock; 10th Jun 2018 at 09:25.
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Old 10th Jun 2018, 09:33
  #51 (permalink)  
 
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Truly extraordinary ignorance being repeatedly displayed by chopjock.

Being totally ignorant of such fundamental principles of weight and lift is quite something by itself, when claiming to be a helicopter pilot.

Worse, flying helicopters when clearly of the mind that exceeding absolute limits by being overweight is 'OK' provided you keep within certain power limits is reckless, and displays a shockingly dangerous attitude to flying.

But worst of all, coming on here - REPEATEDLY - to justify such arrogant, cavalier, blatant disregard for limits based on with such ridiculously flawed and utterly fictitious mumbo jumbo made up myths and nonsense is way beyond stupid.

chopjock, the really frightening thing about you, is that you are SO ignorant, that you really don't have any idea just how wrong and stupid you actually are.

PLEASE, do yourself and everyone a very big favour by grounding yourself until you have undertaken a course of study to learn the very basics of physics as applicable to flight. You also need a fundament change in attitude to appreciate that EVEN if you are too stupid to understand why limits are applied to all aspects of flight, at the very least to realise that they are there to protect ignorant fools such as you from your own stupidity.
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Old 10th Jun 2018, 09:36
  #52 (permalink)  
 
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Ok Chop I'm going to try one more time.

Lets assume that you are hovering on your cold day, at sea level, at design max gross weight and it is only taking you 95% of your max TQ. Lets make this a hypothetical helicopter with a max gross of 2000kg. Your conning angle is, lets say 5 degrees and there is now 2000kg, less the weight of the rotor (lets make that 100kgs), hanging from that rotor i.e. the mast will have a pull of 1900kgs on it. The bearings that hold the mast in will have an upwards pull of 1900kgs on them. You now put 200kgs onto the back floor, right at the C of G, so no effect on C of G. To stay in the hover you have to add pitch, which increases the TQ and will increase the conning angle. Now there will be 2100kgs pulling on the mast and an upwards pull of 2100kgs on the gearbox bearings. There will be 200kgs more trying to tear the gearbox off the roof of the helicopter and there will be 200kgs more load on the frame of the helicopter that holds the floor on, all of this is 200kgs more than it was designed for. Lets say you take off and do a 2G turn, now you will have an extra 400kg load on all those components.

I think your confusion comes from the fact that you think the stress on the engine and rotational components is the same as the stress on the structural components and that is where you are wrong and as an engineer you should know this. You are correct that the engine and the gears in the gearbox won't be able to tell what the weight is and only feel the effects of TQ but as I have shown you above, this is not correct for the structural component's. Excess weight also has effects on other things like auto rotational performance but then you are a pilot and you knew that, right?

Still waiting to see your licences.
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Old 10th Jun 2018, 10:43
  #53 (permalink)  
 
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bront,
Thank you for your concern, obviously your hypothetical helicopter would not be safe to fly in your hypothetical scenario. (You would be over torquing as you know).
So your hypothetical helicopter is sat there in a ground effect hover, already at 95% torque with the max 1900kgs pull allowed on the main shaft. What happens to the amount of pull on the main shaft when you accelerate upwards? It increases, obviously. So there is a max safe limit of the amount of pull you can apply. I'm saying provided you do not exceed this limit, (measured on the torque /tot gauge) then from a stress point of view it's no different, obviously if you can't do it then don't. This max limit allows for a max all up mass aircraft to climb at a given performance. If you add a little more weight you will have to accept a little less performance in exchange, meaning the "max pull" on the main shaft is the same. I would obviously avoid 2g turns if I was over weight!
However there can equally be a scenario whereby you can be at max weight, on a cold morning at sea level and have enough power to climb out at say 800ft/min and measure the pull on the main shaft by observing the torque / tot gauges,(whilst staying in the green) say equivalent to 1500kgs pull on the main shaft.
If you then land and add weight putting you 150kgs over the limit, then take off pulling the same torque as previously noted and being equivalent to the same 1500kgs pull on the main shaft, you will have traded a lower ROC or none at all (perhaps only 250 ft/min) for the extra weight, but with the same pull. Surely?
Anyway, just my opinion every one, for which I am entitled to have... Newbies if you are reading this, when I say it's fine or OK I am referring to a stress point of view. I am not suggesting it's ok for general practice.

Last edited by chopjock; 10th Jun 2018 at 12:18.
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Old 10th Jun 2018, 11:13
  #54 (permalink)  
 
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Originally Posted by chopjock View Post
Anyway, just my opinion every one, for which I am entitled to have...
Actually, no.
This is about physics and physics has nothing to do with opinion. It is all scientifically proven concepts.
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Old 10th Jun 2018, 11:18
  #55 (permalink)  
 
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I am not the brightest in the bunch CJ but please stop!! this is not opinion based it is fact, @bront 's explanation is simple enough to grasp surely
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Old 10th Jun 2018, 13:31
  #56 (permalink)  
 
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Why, oh why, does everyone keeping on feeding the troll?

Even by his own admission:
Originally Posted by chopjock View Post
I am sometimes just giving a different point of view for the sake of discussion and it's working!
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Old 10th Jun 2018, 13:47
  #57 (permalink)  
 
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[QUOTE=Bravo73;10169702]
Why, oh why, does everyone keeping on feeding the troll?
Iím wondering if chopcock has ever had kids. If not heís a dead cert for a Darwin Award when his monumental arrogance and stupidity clears him from the gene pool. If he is a troll then heís in danger of killing others with his posted stupidity, if heís not a troll then whoever taught him to fly is obviously as big a C##t as our hero himself.

I do think a check should be made of N reg H500ís in the UK. If chopcock is real then his aircraft will be traceable and should be condemned, if heís not real then he needs a kicking for posting stuff that new PPLís could follow. And by following kill rhemselves or others.

SND
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Old 10th Jun 2018, 14:02
  #58 (permalink)  
 
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Old 10th Jun 2018, 15:03
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SND
If chopcock is real then his aircraft will be traceable and should be condemned
That's a bit harsh when I have stated
but I never take off over weight and always remain within the green arcs...
if he’s not real then he needs a kicking for posting stuff that new PPL’s could follow. And by following kill rhemselves or others.
I also stated
Newbies if you are reading this, when I say it's fine or OK I am referring to a stress point of view. I am not suggesting it's ok for general practice.
212 man
and so it goes on. CJ, I’d take TC and SND’s advice!
Cheers. Advice taken long ago by the way...
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Old 10th Jun 2018, 15:53
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Sadly chopcock I have met at least one PPL who was going to do something illegal due to one of your postings from a couple of years ago about landing in congested areas.

Youíre not funny, your theories on here could kill, and your theories are read by new PPLís, the media as well as the professionals the forum is aimed at.

Iím not laughing, I donít know anyone else who is, and letís rwmember that this thread started because a ďpilotĒ killed his passengers by behaving stupidly and a coroner thought it was ďbad luckĒ. It wasnít bad luck, that pilot might has well have used a gun on this passengers, the result is the same, the bad luck was a coroner too ill informed to tell the truth.

I donít care if you havenít flown your aircraft overweight, or flown the idiotic IMC let down from the other thread, I donít care of you do or donít fly into congested areas the way youíve described before, I do care that someone may think youíre right and fly an aircraft over weight, attempt your IIMC let down, ignore the law on congested areas and kill a few more people than the owner of G-OHCP managed.

Right now in the UK a review into on-shore helicopter safety is in process. I have no doubts more restrictions are heading our way. I earn my living as a UK based helicopter pilot and the stupidity of the owner of OHCP is one of the reasons for that review, I hope heís proud of himself wherever he is. People like you and him are just making the situation worse, troll or not, it really is time the mods banned you before you harm someone else.

SND
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