BBC News - Safety checks ordered for air ambulances across England (http://www.bbc.co.uk/news/uk-england-17661797)

unless you want to spend a long time grounded due to cracks in the rotorhead.

I don't think any (besides the cracked) 135 was grounded. Its just an inspection until they find the cause.

Just to throw a bone back... What are you gonna fly? Bells virtual devices or Agustas fibers? All manufacturers have their own issues to resolve.

Really? I only see safety information notice at T.i.p.i. no grounding.

After an incident of a cracked main rotor hub-shaft (see figure 1) which is still under investigation, Eurocopter has published the Alert Service Bulletin EC135-62A-029 to inspect the upper and lower hub-shaft flange of the main rotor hub-shaft for cracks.
After accomplishment of Alert Service Bulletin EC135-62A-029 a second crack has been detected during a preflight check (see figure 2 and 3).
In order to be able to detect possible cracking, Eurocopter will introduce a visual check for possible cracking at the preflight check. The Alert Service Bulletin EC135-62A-029 will be revised. The Flight Manual (FLM) is in process of revision and will be distributed by a temporary revision:

The phone call about grounding or that it is a possibility for grounding the aircraft?

that story is only a month old. well spotted!

Ironcheffy, maybe its happened again :ok:

Twice............

or Thrice.....................................?

Just to stop the rumours and to highlight the matter to those operators here (private?) that may not already know, another cracked flange was found yesterday and pre-each flight checks are now taking place.

Whether or not any operators have actually grounded their aircraft is a company matter on which I cannot comment.

Very diplomatic for you Sid!

News link (http://www.bbc.co.uk/news/uk-17993232):(

Air ambulance services grounded over safety fears

Large parts of the UK are without any air ambulance cover after the main helicopter operator grounded services over safety fears.

Bond Air Services has withdrawn all 22 of its Eurocopter EC 135 helicopters over concerns about possible cracks in the rotor blades.

The model is used by air ambulance services in Scotland, Wales, the North West, Hampshire and other counties.

A spokesman for Bond said safety had to come first.

Bond said a safety notice had been issued by Eurocopter on Sunday morning, urging operators to increase the frequency of checks on the EC 135 after cracks were found in several helicopters.

Eurocopter has not ordered that the fleet be grounded, but Bond said it felt compelled to take that decision.

"We take the view that this has been going on long enough.

"Eurocopter need to give a definitive statement about the problem and the solution to it.

"Until that happens we've taken the view that safety comes first and have suspended the service."

Tim Macmahon, director of government and public affairs at Eurocopter UK, said the advice was to step up checks while the company awaited further advice from its own airworthiness investigators and the European Aviation Safety Agency.

"That work is urgently going on, but it is always the final decision of the pilot or the operator whether to fly or not," he said.

Grounded ...... As Bond have just done in UK (Air Ambulance)?

Scotland's only two air ambulance helicopters grounded because of safety fears - The Daily Record (http://www.dailyrecord.co.uk/news/scottish-news/2012/05/08/scotland-s-only-two-air-ambulance-helicopters-grounded-because-of-safety-fears-86908-23852540/)

22 machines?

Funny how the seem to not be mentioning the Police also being grounded. :O

Should this be on the EC135 thread?

Based on the information and the current suggested method of dealing with the issue by ECD.......................a very sound decision.

BBC News - Air ambulance services grounded over safety fears (http://www.bbc.co.uk/news/uk-17993232)

They could always borrow XMII :ok:

Any info about two choppers with cracks? I mean SN and TT.

They could always borrow XMII

They could while it is still here, heard a rumour it had been sold. G INFO has it as "an Export C of A applied for" due for process tomorrow!

are the police ships having the same problems

All inaer group Ec-135 have been ground not just bond. In Spain all ec-135 are on ground waiting news from eurocoter.

Three EC-135 used by police in Wales are grounded- along with 2 of the 3 air ambulances covering the Principality!!

not saying i told you so... but i told you.

I flew past a police operated EC135 today, and what's more, it was airborne.

:ok:UK Emergency Aviation - Latest Updates (http://www.ukemergencyaviation.co.uk/Updates.htm)

Frozenpitot;
not saying i told you so... but i told you.

I don't think so :rolleyes:

that's because you missed last nights post


You have deleted four posts so far in this thread. Common practice is to refer to what you have online, not what you think others should know by osmosis :rolleyes:

Splot

Further to Blind Bob's link: Air ambulances ungrounded (http://www.scotsman.com/news/transport/scotland-s-air-ambulances-back-in-air-after-cracked-rotor-fears-1-2281553)

Good morning from the Sunny North of England,

The problems will lie with some manufacturing process allied to the possible wrong spec of steel or alloy used to produce the shaft and flange, it could be as simple as a wrong or incorrect annealing process right back when the original bloom of steel/alloy was produced.

Whatever the cause when cracks develop in such a high spec piece's of Steel/Alloy, it can lead very quickly to a total and destructive failure, on the ground that would be dangerous, it the Air....?

Its time to stop waiting for a result and sitting on hands, for this could even be inherrant in any "New Spares" that are brought of a shelf somewhere.

It is quite unbelievable that anyone should even consider flying any sort of machine with a crack in such a serious and critical part of the spinning machinery. irrespective of such good advice as to add to the pre-flight.

Peter R-B
Lancashire

that's because you missed last nights post

Oh, OK. Perhaps an alteration to or deletion of your post would have been nice.

Good morning from the Sunny North of England,

The problems will lie with some manufacturing process allied to the possible wrong spec of steel or alloy used to produce the shaft and flange, it could be as simple as a wrong or incorrect annealing process right back when the original bloom of steel/alloy was produced.

Whatever the cause when cracks develop in such a high spec piece's of Steel/Alloy, it can lead very quickly to a total and destructive failure, on the ground that would be dangerous, it the Air....?

Its time to stop waiting for a result and sitting on hands, for this could even be inherrant in any "New Spares" that are brought of a shelf somewhere.

It is quite unbelievable that anyone should even consider flying any sort of machine with a crack in such a serious and critical part of the spinning machinery. irrespective of such good advice as to add to the pre-flight.

Peter R-B
Lancashire

And just how would you qualify that opening paragraph Peter?
Referring to your last paragraph, may I remind you of your profile...Current a/c Type R22, R44, B206, flirted with Gazelle :eek:

About turboshafts link;

Scotland (http://www.scotsman.com/news/transport/scotland-s-air-ambulances-back-in-air-after-cracked-rotor-fears-1-2281553)

The Scottish Ambulance Service had suspended flights of two air ambulances over safety concerns

Cracks found on the two helicopters have prompted fears over the EC135 model

Lots of media speak around, but can someone with more than a hanful of posts confirm whether 2 of the 3 aircraft found with the cracks are actually these 2?
If so, where was the third, and if not where were the 3?

Technical translations are so tricky, aren't they? :}

BBC News - Scottish air ambulances fly again after safety checks (http://www.bbc.co.uk/news/uk-scotland-highlands-islands-18000313)

No issues with police cabs. Pre flt checks now incorporate this inspection. It seems that currently, it's only the air ambulance cabs (UK) suffering.
It's not a show stopper, the head won't come off if the crack migrates!
It may even be (allegedly) a servicing issue where these rotor heads are torqued (or over torqued) differently dependent on the maintenance provider(s).
All in all - a little bit of over cooked media hype.:=

TC,

I have to admire your optimism!

Consider the following -

The jury is still out on this one.

The way the bulletin is worded you have until the 30th of this month to inspect the aircraft. The AD actually has a compliance date of 12th of June (go figure)

After inspection there is no need to contact or establish with the manufacturer that there are no cracks. Just make an entry in the historical records and the component log card.

That being the case and at least 2 cracks have been found how big do you think the data sample is and how many of the total in service have actually been inspected to date?

2 out of 200 inspected so far would be a concern.

Bulletins of lesser importance have included a feedback form to establish the quantity and serial number of aircraft that comply or are not affected.

In this case the problem is to date ECD have absolutely no way of knowing how many aircraft are affected unless a crack is found and therefore how big the problem is until the end of the compliance period. (i.e. the end of this month)

Possibly they are aware of the issue and are not concerned, who knows.

Definitely not me and definitely not you I would guess.

Don't count your chickens just yet........................................

The PR with the customer could definitely have been better considering the severity of the problem.

Hello,

When I saw the pics for the first time, The first thing what came to my mind was; look at that corrosion and rusty color not only on the hub it self also on the pitch links eye-end they where also corroded.
Probably these ships have been flying in a salty environment and in addition to this they have not been maintained in a controlled environment.

I just can't believe any ground engineer/pilot who sees the beginning of corrosion and the brownish slush coming out of the bolt hole bushing during his DI will not scratch his head and will investigate this.

Dragstay

Dragstay,

The pic with the "brownish slush" is actually the teflon material from the bushing liner.

Agreed the second pic does not look real good.

I seem to remember many moons ago that DC10.s were having cracks in their engine pylons, one even crashed. All were grounded!

As I recall that turned out to be down to a maintenance issue when one particular airline did it slightly differently to the shedule.

whitehead 06

Spanish to English translations (technically) can be terribly difficult!

not saying i told you so... but i told you.

frozenpitot - in your original posts you seem to have indicated that you have a lot of technical expertise and knowledge of the EC135 series, and have more of an insight into this issue than the manufacturer and the major operators? Care to enlighten us all on how you know so much?

BC

The pic with the "brownish slush" is actually the teflon material from the bushing liner.


Are the pictures online anywhere?

C'mon Frozenpitot you were very critical about the EC135 earlier. What now? you've gone very quiet!

whitehead06

Good morning Silo,

Earlier life in the Steel industry, tells you many things when dealing with special steels and Alloys, many things in pre production shapes can be affected by only +/- a few degrees of heat when forging or annealing after and when normalising the steel, like any other trade problems only show up when the finished product is pressed into use,
Like all the rest this is just my two penorth!

Peter R-B
Lancashire

Thanks Petr and good morning to you.

I wonder if EC will be looking at that :rolleyes:

Silsoe: Peter means well. He's making observations based on his background, which does have some correlation to what the problem may be - perhaps?
Cut him some slack mucker.......:)

Good morning TC,

I have broad shoulders, but thank you for springing wraith like to my defence, I hope you are well.

Peter R-B
Lancashire :D

I wonder if anyone's observations go as far to notice the bent locking pin in the 'dirty photograph' and thought ' how much anti clockwise force has to be applied to the bolt in order to bend the pin that much.
Normal vibration?!

Nigel321, the Safety Information Notice 2450-S-62 is online at www.eurocopter.com/techpub, but you need a login.

By the way everyone, are the pics titled correctly? :confused:

By the way everyone, are the pics titled correctly?If you are referring to the words Main rotor Hub-shaft flanges - Condition, no cracks over the first picture, I think thats no title. Its the upcoming entry for the FLM.

skadi

This reminds me of the detached Lynx blade debacle in the early 90's (I think). The commercial reaction from Westlands was "everything is fine" and next to no info. The outcome was very different with most of the tie-bars being found to be U/S on inspection. The lesson from that is a rapid investigation and honesty from manufacturers is what is required.

Skadi, you are probably correct.


F4F, I think this PPRuNe thread follows up on your post http://www.pprune.org/rotorheads/19120-gazelle-crash.html

More specifically about the Lynx in Sept 1994;
Westland plans to replace Lynx blade-assembly part (http://www.flightglobal.com/news/articles/westland-plans-to-replace-lynx-blade-assembly-part-21518/)

Westland plans to replace Lynx blade-assembly part

A CRITICAL PART of the Westland Lynx main-rotor- blade assembly is being replaced on a precautionary basis, with the UK manufacturer admitting to being "confused" over the underlying cause of a fatal Lynx accident in September 1994.

The loss of a British Army Air Corps Lynx in Germany was attributed to a catastrophic tie-bar failure. The tie-bar is situated between the rotor head and blade, and absorbs centrifugal and torsional blade stress.

Although the tie-bar was originally intended to be stressed for the airframe life of the helicopter, Westland is now replacing the part every 1,500 flight hours. Inspections are also being carried out every 200h.

Westland says that it has so far been unable to find a " definitive cause" for the failure. The tie-bar was originally stressed to a 90,000kg breaking tension, although, during its life, this could reduce to 55,000kg. Westland says that the maximum tension it would expect on any tie-bar during flight is 41,000kg.

Westland is being particularly cautious in not writing the incident down as a one-off. It has also found " unexpected wear characteristics" in a "minority" of the Lynx tie-bars it has inspected.

It is also anxious to understand fully the cause of the failure because it plans to upgrade the Lynx airframe to allow it to stay in service until 2035 (Flight International, 21-27 June).

The company appears to have ruled out a manufacturing problem as the root cause of the failure, or as a cause of greater-than-projected wear on other tie-bars.

"If anything, the pattern is more akin to the type of use," says the company.

If memory serves me right, I think there was a 206 pilot that saw the Lynx incident :(


Flight International article 26 Oct - 1 Nov 1994;
dornier | westland | fokker | 1994 | 2587 | Flight Archive (http://www.flightglobal.com/pdfarchive/view/1994/1994%20-%202587.html)

Silsoe I did not post on the Gazelle crash thread at all so not sure what you mean.

F4F,
Oops! I didn't mean to say that you posted on that other thread, I guess I should have put in a comma.

Just highlighting that with the tie bar incidents, eventually the Gazelle AH1 ZA777 (http://aviation-safety.net/wikibase/wiki.php?id=65037) incident was considered a one off, where as the Westland Lynx AH7 XZ650 (http://aviation-safety.net/wikibase/wiki.php?id=64955) wasn't.

You are of course right Silsoe, my point I suppose is a willingness of companies to put possible commercial interests above safety, which is wrong, but in this [EC135] case I am sure that they are, and will continue, investigating and do not compromise safety. Their reputation is a very good one unlike some other manufacturers whose types I have flown.

Page 5 has two photos of the cracks, (sorry could not just link the photos):

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAD.nsf/0/81057104f9c9fc1d862579ff0070c3a3/$FILE/2012-10-51.pdf

SUBJECT: MAIN ROTOR SYSTEM -- Main Rotor Hub-Shaft Revision 1, 2012-05-16

Visual inspection of the upper and lower hub-shaft flange for cracks

EFFECTIVITY Main rotor hub-shafts with more than 400 fh TSN (Time Since New).

In addition to the implementation of a preflight visual inspection which should not exceed 6 hours between inspections -

(a) Accomplish the visual inspection in the area of the blade bolts i.a.w. Section 3.B. Part 3
within the next 10 fh after receipt of this Alert Service Bulletin and repeat every 10 fh.

Inspect the area of the blade bolts of the lower hub-shaft flange for cracks:
(1) Remove the safety pins (4, Figure 3) and the nut (3) from the blade bolt (5).

(2) Carefully remove the washer (3, Figure 4) from the lower hub-shaft flange (1), using e.g.
a sharpened spatula (see Figure 4)

(3) Inspect the area of the blade bolt attachment i.a.w. Figure 5, using e.g. a “micro camera”
or a flashlight and a mirror / magnifying glass (at least 10-fold magnification power).

1.G.MANPOWER
Mechanic
Time approx. 2.5 h -- (Each 10 hours of flight)

Yupp the first photo is of the Scottish Air Ambulance and it had 3200hrs.
This one had a two stage crack I was told by ECUK.

The second is also a Bond aircraft sadly no details about the hours. This one seems to be just one crack.

The third is a French 135 that is what I was told by and ECUK engineer.

Any update, or pictures, of the French occurrence?

I love the EC135, but right now I would not enjoy being one of the guys tasked with selling them. An inspection that takes 2 1/2 hours for a mechanic every ten hours of flight time. An inspection by the pilot every time the engines stop.

If I owned Eurocopter stock, I'd own less of it today.

Rubbish, a temporary solution to keep the fleet flying. All types have problems at one stage or another. 902s still sell after their blade bolt and gearbox problems. This will not be forever

Well, I see two possible fixes:
1) they build rotor masts with more material on the outside of those holes, supply them to everyone and take the hit;
2) they tell us, "hey, it's only three cracked rotor heads - your chances are actually very good!"

Or more like, after a period of no cracks found at 10 hour inspections the time limit moves to 25 hours, then 50, then 100 and there it will stay.

And (never start a sentence with the word 'and':ugh:), we'll never know what the cause was. Pilots will suspect a bit of heavy handed maintenance, engineers will suspect cack-handed pilots!

jayt

902's are actually being sold still?

TC

engineers will suspect cack-handed pilots!

Or more likely, engineers will suspect cack handed engineers. Over torqued bolts anyone? Bueller? You at the back with the broken torque wrench, yes you. Stand up. :p

Some 135's are on their 5 or 6th 10 hour inpspection now, and we've found nothing (as far as I'm aware) I hope ECD get their data sorted and move this inspection to a more suitable time period (check A then 100hrs would do)

:p You know what I meant. VW and Audi cars got recalled for various things and they still sell well. Today is the 135, tomorrow it will be a different type.

I'm going with Handysnaks theory, it may happen again but they will sort an inspection regime.

Motorsykkelulykke på Tysnes - bt.no (http://www.bt.no/nyheter/lokalt/Motorsykkelulykke-pa-Tysnes-2711076.html#.T7_2gcX4LoA)

Inspection while waitng for the patient, maybe?

http://bt.mnocdn.no/incoming/article2711091.ece/ALTERNATES/w980c169/20120525_205613.jpg

SIN 2457-S-62 Main Rotor Hub-Shaft: Check of the upper and lower hub-shaft flange for cracks.

The latest information.

Details regarding the Three Main Rotor Hub Shafts:
• The flight times of the Main Rotor Hub Shafts were 857, 1428 and 3070 fh.
• The Rotor Hub Shafts were not from the same batch or serial number range.
• The affected operators were all European operators.
Note: Each operator with different flight operations including: Police/EMS, Harbour Pilot transfer and Off-shore.

Common Points with the Three Main Rotor Hub Shafts:
• Point of crack initiation. Cracks have initiated at the top side of the lower flange at borehole under the bushing
• Same crack propagation and evolution behavior (for the third Rotor Hub Shaft this is to be confirmed following the test bench activities)
• Crack is located at the leading edge of the lower hub shaft flange lug
• Fracture surface reveals constant propagation rate over the entire surface (to be confirmed on the third rotor hub shaft following test bench activities)
• There is no increase in the crack propagation rate prior to the point of static rupture
• All other lugs were found crack free
• The bushings have never been replaced on the lugs where the crack occurred
• Main rotor hub shafts were not subjected to / or reported
with overspeed, overtorque or excessive mast moment exceedance (mast moment indicator was functioning)
• No reported ‘special operations’ or exceedences of the published flight envelope
• No noticeable change in vibrations were reported prior to crack detection
• No corrosion pitting identified at point of crack initiation
Note: The operators did not have the same operational profile.

Ongoing Investigations:
• A multifunctional team has been created and is working on this subject with the highest priority
• Full scale component test of the 3rd cracked mast to determine the crack propagation
• Flight test will be performed to support the on-going investigation
• Common in-depth investigation with suppliers

ECD Top Priorities:
1. To understand the root cause of the failure in order to define a corrective measure.
2. To extend the inspection interval in the EASB EC135-62A-029.
As soon as further information is available it will be distributed by the appropriate means.

Is it correct that beside these 3 masts no other mast was found with cracks in the worldwide fleet of >1000 EC135s? There must have been a lot of the EASB EC135-62A-029 inspections in the meantime...

skadi

Some aircraft in the UK are on their 8th or 9th inspection. No cracks or serious corrosion found to date.

I hope ECD reach a reasonable conclusion soon.

Are the 3 aircraft P2/T2 + aircraft?

The part is the same regardless of P/T variant.

Curious if the extra gross weight could be a factor.

Inquiring minds on a slow weather day, combined with RVDT's post and little information from the local EC Rep left our mechanic scratching his head. He was happy we had a weekend of bad weather.

I doubt it. The Police/EMS and the O&G support helicopters might be flying near max gross sometimes, but the harbour pilot transport helicopter shouldn't have been.

Any updates so far?

skadi

None as yet.

Many thanks to RVDT

Unless miracle will happened we will have these 10hrs inspection forever.

Have some faith. That miracle may well come in the shape of the Eurocopter sales figures. In my area I've noticed a drop-off in our flight volume as our competitors (who don't fly EC135's) make sure that all the hospitals in our area know that they fly the helicopters with the blades that stay on.

I'm not saying that's fair, just saying that it might be the reason why we don't get as many calls as we used to. EC will fix the problem or sell a whole lot fewer helicopters in future and they know it. Telling every customer that they have to climb up in the rotor system every time it shuts down to see if it's broken yet is not the way to inspire confidence in the product.