Go Back  PPRuNe Forums > Aircrew Forums > Rotorheads
Reload this Page >

CHC AW 189s

Rotorheads A haven for helicopter professionals to discuss the things that affect them

CHC AW 189s

Old 9th Dec 2018, 21:04
  #21 (permalink)  
 
Join Date: Sep 2004
Location: daworld
Posts: 642
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by driftwood1

I understood what the post meant but thank you for clearing that up. I will make my question more clear...... Exactly when did CHC Australia stuff up a weight and balance on its AW139 fleet and do you know or understand the processes required to carry out a weight and balance in Australia.....
It was quite a while ago now. I believe I was still a Crew Chief at CHC Global when it happened but can't be 100%sure. Might have been just after I left. It was certainly before the 7000kg upgrade came out. I either heard about it through SQID reports or company email. Just not sure which company

And yes, as a Licenced Aircraft Maintenance Engineer I am very familiar with weight and balance and I also know that when you had a crap load of loose equipment/survival equipment to the aircraft, it needs to be recorded.
noooby is offline  
Old 10th Dec 2018, 04:24
  #22 (permalink)  
 
Join Date: Apr 2000
Location: EGDC
Posts: 10,289
Received 608 Likes on 266 Posts
Perhaps they did not know....thus why would their "Ticket" be in jeopardy?
If you sign for the aircraft and spank it in following a performance chart that the mass of the aircraft exceeds - whether it is an engineering snafu or just not checking the C of G and Mass properly - it's still going to be the pilots fault.

Fortunately - and it seems so in this case, the error was noticed (sometime later) and the only red faces are the engineers who got their sums wrong. I have challenged weight and balance sheets before when thing didn't look quite right as I am sure many here have.
crab@SAAvn.co.uk is offline  
Old 10th Dec 2018, 06:06
  #23 (permalink)  
 
Join Date: Sep 2002
Location: Great South East, tired and retired
Posts: 4,349
Likes: 0
Received 193 Likes on 89 Posts
If it was overweight, was it also way outside C of G?
Perhaps the pilots may have noticed if it was outside cg? Like, unable to control the attitude on pickup, rapidly put it down again?
Ascend Charlie is offline  
Old 10th Dec 2018, 06:27
  #24 (permalink)  
 
Join Date: Nov 2001
Location: Norfolk
Age: 84
Posts: 298
Likes: 0
Received 0 Likes on 0 Posts
Depressingly, over the years I found that there were lies,damned lies and weight and balance sheets. In the process of working from the as weighed figure to the notional basic weight, and then the aircrew working forwards to the role equipped weight, the opportunities for error were huge because the numbers were so large. Instances like fixed ballast added when role mods were incorporated, but not removed when when the mod was removed, role equipment weights incorrect (invariably heavier). In one case the manufacturer’s figures for an aircraft submitted for test were in error, resulting in a hasty correction when challenged. And so on!
rotorfossil is offline  
Old 10th Dec 2018, 07:35
  #25 (permalink)  
 
Join Date: Aug 2000
Location: Asia/Oz
Posts: 219
Received 0 Likes on 0 Posts
This issue (overweight CHC 139's) was discovered about 6 years ago. It wasn't the whole CHC 139 fleet in Australia as someone has suggested, but just 2 aircraft in Karratha (the only ones on contract) in the offshore role. Weight and balance was calculated in good faith before each flight, with operations planned within PC1 limits, and the aircraft were never knowingly operated overweight. This went on for nearly 2 years from memory. Two new aircraft then arrived on contract and the RFM empty weight of both was around 200 kg heavier than each of the "old" aircraft, for no apparent reason. The original aircraft were then re-weighed, and subsequently found to be approx. 200kg heavier than the aircraft empty weight recorded in their respective RFM's. Nothing to do with incorrect sums or equipment not being counted, so no matter how diligent you might be in checking your paperwork before flight you would not have detected the error. I don't recall exactly how the original incorrect empty weights in the W & B section of the RFM occurred, but I believe they were there when CHC Oz took delivery.
Mark Six is offline  
Old 10th Dec 2018, 13:11
  #26 (permalink)  
 
Join Date: May 2002
Location: Downeast
Age: 75
Posts: 18,267
Received 467 Likes on 191 Posts
Crab stated this......

If you sign for the aircraft and spank it in following a performance chart that the mass of the aircraft exceeds - whether it is an engineering snafu or just not checking the C of G and Mass properly - it's still going to be the pilots fault.

Mark Six told us this.....

​​​​​​​ The original aircraft were then re-weighed, and subsequently found to be approx. 200kg heavier than the aircraft empty weight recorded in their respective RFM's. Nothing to do with incorrect sums or equipment not being counted, so no matter how diligent you might be in checking your paperwork before flight you would not have detected the error. I don't recall exactly how the original incorrect empty weights in the W & B section of the RFM occurred, but I believe they were there when CHC Oz took delivery.

Crab also told us he has challenged "questionable" W and B Data in the past.


So, Crab young Lad, please do explain exactly why you would "blame" a pilot for a 200 kg error in the W&B data used when it comes directly from the RFM for that particular aircraft he is flying that day and had done what Mark Six points out?

We are talking about a two and a half percent error....that is not very much.

The only two aircraft on the Operation had similar errors and similar weights per their RFM's.

You really think it was the Pilot's fault do you?

Explain please....just how was a Pilot on that Operation supposed to determine there was a problem?

Please do not try to tell me they should have known from the performance (or lack of.....) felt each time they flew the machines....as that Dog won't hunt!
SASless is offline  
Old 10th Dec 2018, 14:18
  #27 (permalink)  
 
Join Date: Apr 2000
Location: EGDC
Posts: 10,289
Received 608 Likes on 266 Posts
Sas - you are like the proverbial dog - not a hunting one but one with a bone

My only point was that an investigation into an accident that was caused by operating overweight would inevitably focus on the pilot who would then need a very staunch defence to prove it was manufacturers/weighing/role equipment discrepancies et al to blame.

Fundamentally you sign for it you are saying you checked it.
crab@SAAvn.co.uk is offline  
Old 10th Dec 2018, 15:13
  #28 (permalink)  
 
Join Date: May 2002
Location: Downeast
Age: 75
Posts: 18,267
Received 467 Likes on 191 Posts
My point is simple....you do your job properly....and carry out the preflight planning and related procedures and you cannot be found at fault.

The Pilot has to rely upon the data he is provided being accurate re Weight and Balance and Engineering actions that lead to the Aircraft being presented as "Serviceable" and safe for flight.

Absolutely the Pilot's actions will be examined but it would be an absolute defense against civil, criminal, or administrative action if he can demonstrate he took the proper actions.

Likewise....as in this case.....it is the Engineers who signed on the dotted line that would wind up carrying the bucket (or should).

As part of the Certificate of Airworthiness....the aircraft should have been inventoried, weighed, and a CG calculated per the Authority's Regulations.

Once that is done....that data is entered into the Aircraft Documentation.

The Pilot's calculation should have confirmed the Mission Equipment and other items were accounted for when he did his own W and B calculations prior to flight.

I cannot remember ANY time a Line Pilot has queried the basic weight and balance data for the RFM/Aircraft Records as part of his daily preflight preparation.

I have as you have said....challenged a weight and balance report AFTER discovering unlisted items on the Inventory (four sets of Speakers in the cabin overhead behind the sound proofing and some other items)....and was very dismayed by the Company's reaction.

But then.....knowing the Company in question that really did not surprise me.

When one finds a tail rotor pitch change link dangling loose after a Tail Rotor change....and the Logbook signed off as Test Flown and Released for Service.....and neither the Engineer or Pilot involved got reprimanded....what's a bit of extra kit on the aircraft and not on the W and B Documents.
SASless is offline  
Old 10th Dec 2018, 19:30
  #29 (permalink)  
 
Join Date: Apr 2000
Location: EGDC
Posts: 10,289
Received 608 Likes on 266 Posts
Sas - you do need to get out more - you are spending so much time arguing every point on these threads you might be turning into he who must not be named on pprune

If you start arguing about numbers of engines then I'll know you have lost it
crab@SAAvn.co.uk is offline  
Old 10th Dec 2018, 21:33
  #30 (permalink)  

Avoid imitations
 
Join Date: Nov 2000
Location: Wandering the FIR and cyberspace often at highly unsociable times
Posts: 14,560
Received 402 Likes on 210 Posts
Not so long back I was tasked with checking the details of a used helicopter for a potential buyer. When it came to checking the empty weight of the aircraft I studied the factory weight and balance schedule (in the individual RFM) to calculate a few typical mission profiles. Whatever calculation I did, the C of G was well outside the envelope. Even the zero fuel figure, with one pilot up front, was 4" outside the fore/aft limit. I asked for the aircraft to be re-weighed and this showed that the original factory figures were nonsensical and were nowhere near reality. I used the new W & B schedule for my original calculations and found the aircraft fore/aft C of G to be as close to neutral as any could be.

Two worrying things:
1) The factory figures should have been absolutely correct in the first place and whoever did the weighing should have noticed what must have been large discrepancies from normal figures on that type of aircraft.
2) I was probably the first person to ever carry out a mission W & B calculation on that aircraft. If the original figures had been correct, it had been inadvertently operated for almost four years with a C of G approximately four inches outside limits!
ShyTorque is offline  
Old 10th Dec 2018, 22:11
  #31 (permalink)  
 
Join Date: May 2002
Location: Downeast
Age: 75
Posts: 18,267
Received 467 Likes on 191 Posts
Air Navigation Order Section 2-43 pertains to Weight and Balance.

The Air Navigation Order 2016

"Must be weighed", "Must be documented", and "Must be provided to the Pilot" stand out along with a requirement to retain the old W and B Document for a period of Six Months following a re-weigh.
SASless is offline  
Old 10th Dec 2018, 22:35
  #32 (permalink)  

Avoid imitations
 
Join Date: Nov 2000
Location: Wandering the FIR and cyberspace often at highly unsociable times
Posts: 14,560
Received 402 Likes on 210 Posts
SAS, I don't know who your post was aimed at - but the aircraft I refer to was on the N reg...

The old schedule was retained for posterity and amazement.
ShyTorque is offline  
Old 10th Dec 2018, 23:16
  #33 (permalink)  
 
Join Date: May 2002
Location: Downeast
Age: 75
Posts: 18,267
Received 467 Likes on 191 Posts
The post was generic.....not directed to any individual.

As this is a somewhat UK Centric Forum....I was trying to use the UK ANO as a reference.

I can add the FAA Regulation if you wish.

The basic premise is the aircraft has to have an equipment inventory done, be weighed, and a CG determined based upon that data.....and that be the starting point for the Crew to determine the Weight and Balance of the aircraft when prepared for their particular flight.

If the data provided to the Crew is in error then naturally their calculations are based upon a false premise but due to no error of their own.

You were sharp enough to smell a Rat when your calculations kept coming up out of tolerances and then do a followup to determine what that cause was.

I would assume if the prospective buyer went through with the purchase he had the aircraft properly weighed and its correct CG determined.

That discrepancy would have raised some other Red Flags I should think.


FAA Information....

https://www.faa.gov/documentLibrary/.../AC120-27E.pdf
SASless is offline  
Old 10th Dec 2018, 23:28
  #34 (permalink)  

Avoid imitations
 
Join Date: Nov 2000
Location: Wandering the FIR and cyberspace often at highly unsociable times
Posts: 14,560
Received 402 Likes on 210 Posts
I would assume if the prospective buyer went through with the purchase he had the aircraft properly weighed and its correct CG determined.
Yes, I did write that it was done ..
ShyTorque is offline  
Old 11th Dec 2018, 09:07
  #35 (permalink)  
 
Join Date: Mar 2016
Location: Underneath the Radar
Posts: 182
Received 4 Likes on 3 Posts
Back to the AW189s, I heard from one of the drivers at CHC that the issue was an incorrect weight from the factory. The machines were grounded on the Friday, inspected over the weekend and back in service Monday. No biggy.
rrekn is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.