Aer Arran Incident - Manchester

[1station]

Aer Arran ATR has had a brake failure on stand 7 this morning. No injuries however a good deal of damage caused as propellers hit stop mirror!!!

http://i881.photobucket.com/albums/ac19/pauldownham/Image0005.jpg

[Captain Planet]

Ouch!

Must have been winding down to H mode with that little damage, but still it will be on the ground for a long time! Lucky the prop didn't shatter in to the fuselage!

CP.

[Jetgate]

Were these folks taxiing on one engine...?

The reason why I'm asking is that coincidently only a couple of days ago talking with a line trainer on the merits of why we should/shouldn't single engine taxi at my company after watching an Arann ATR taxi on one engine to the R'wy at BHX, he told me about a similar incident on an ATR when the crew experienced a Hyd problem whilst single engine taxiing and thus parked themselves inside a building..? Just a question, probably no connection......

Hope all involved are well.

[FlyboyUK]

See the fire crews are putting down sand in the phot, was there a fuel/hydraulic leak caused by the incident?

[jerboy]

See the fire crews are putting down sand in the phot, was there a fuel/hydraulic leak caused by the incident?

You can see some fluid on the center line, difficult to tell what it is though!

Looks like they totalled that GPU pretty nicely, bet it was a bit of a shock to the pax in the windows next to the props...

[powdermonkey]

The long trail of fluid is the cause of the incident....:-)

[Papa2Charlie]

In word...expenisve....new blades and an probably an engine change. Wouldn't have thought it would take too long to accomplish the change.....assuming they have a spare engine.

Looks like the brakes just failed rather than a hotel mode problem given the position of the ground services. I'm assuming the hydraulics are routed through that area?

[powdermonkey]

Hydraulic bay located left hand gear fairing.
As for the taxi on one engine, as long as the ACW BTC is made, you will not lose hydraulics when taxing on one engine. Besides the fact that you have emergency braking available should the pumps fail. Problem seems to be loss of fluid ( a lot of it) and so no pressure in the system, no brakes!

[flatliner]

with either prop spinning there should be no hydraulic redundancy.
I don't think a single engine taxi would be an issue unless when shutting down the no:1 the ACW BTC didn't close for crossfeed and they may have lost the use of the parking brake .

[Rampmole]

http://photos-c.ak.fbcdn.net/hphotos-ak-snc1/hs217.snc1/8427_1189023737511_1585886263_30479829_3646351_n.jpg (http://www.facebook.com/photo.php?pid=30479829&id=1585886263)
http://photos-f.ak.fbcdn.net/hphotos-ak-snc1/hs275.snc1/10223_1189013817263_1585886263_30479827_2538902_n.jpg (http://www.facebook.com/photo.php?pid=30479829&id=1585886263)

[Papa2Charlie]

Thanks for the info Powdermonkey.

The last pics show some blades which are probably of more value on Ebay following this event. :{

Does anyone know if they have to change the engine also? I'd imagine the impact has put a faily sizeable shock through the reduction gearbox but would this necessitate an engine change? Out of curiosity, does anyone know how they managed to stop the aircraft? I don't think the post/mirror they hit would be 'sturdy' enough to stop the aircraft.

[adverse-bump]

Take a closer look at the pics.

Its more obvious when you go take a real look at it, but the number 2 has been pulled of the engine mount and is hanging down at quite an angle! i think engine change is the least of the worries, how about a new spare...

[quazz]

as long as the ACW BTC is made, you will not lose hydraulics when taxing on one engine

You will if one or both systems are leaking and judging by the trail of fluid following the aircraft it looks like at least the Green system has gone over the side.

Papa2charlie
even if the green hydraulic system (supplying the landing gear and brakes) is gone there are still the emergency brakes which will give a very limited 5 applications on the parking brake detent

[Jetgate]

http://www.aaib.gov.uk/cms_resources.cfm?file=/ATR%2042-300,%20G-BUEB%2008-94.pdf

[Papa2Charlie]

I'd be stunned if the engine has been pulled from it's mounts. I know from larger engine types that the cert criteria are very stringent when it comes to mounts and a simple collosion like this should not pull the engine from its mounts. The metallic band around the nacelle is a standard feature of the PW120 series and I'm guessing is to cater for thermal expansion in the nacelle?

Thaks for the info quazz.

[powdermonkey]

Quazz As I stated this is due to loss of hydraulics, blue and green systems are fed from same tank. I was explaining that single engine taxi isnot an issue as long as your Np is generating ACW on one side, PROVIDED no leaks or fluid loss! The fact the emergency or parking brake accumulator did not seem available indicates complete hydraulic fluid loss, as indicated by the long wet trail down the center line! Engine mountings are fine btw! New prop yes, reduction gearbox....... mmmmmm As for the last post by "non iron" how does your statement help anyone????? Do u know the full circumstances?

[SRTDub]

I couldnt imagine that the engine would have been pulled on its mounts, as ive seen larger turbine engines withstand far greater impacts and not budge, those atr 72 engines always look like they are hanging at an angle anyway, as for the shock factor engine will probably have to be removed and a shock loading inspection done. Mounts will probably under go NDT inspection aswell.
By the way the GPU looks fine to me, i think it was the parking mirror that took all the impact.
Anyway im glad nobody was hurt, looks like a serious hydraulic fluid leakage!!

[non iron]

l`m informed by a mate there that it was a genuine failure, so will apologise and shut up.

[remoak]

non iron

A big hunk chewed out of the leading edge is hardly a "nick".

I noticed that you were quick to bag the crew on the other thread as well. Assuming that the trail of fluid being attended to by the RFS is hydraulic fluid, they had a major hydraulic leak during the last part of their parking manouver. This is obviously the worst possible time, after they had checked the brakes and just before they were due to stop. Almost no time to take corrective action.

I know quite a few RE crews, there are a few 10,000 hour skippers there, and most of the rest have a lot of experience. your comments are way off base.

[Ian Brooks]

Remoak
Totally agree with your lasthttp://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/embarass.gif
If your are even only doing 3 to 4 miles an hour and you hit something you know
about, you don`t much time to react and think of another option when you have only 30 or so feet before you hit the pier

Ian B

[Riccardo]

Anybody know how fast was the prop spinning when she hit?? Looks to me as though three blades are damaged so I guess the prop stopped in 3/4 of a rotation.

I was on the repair team when a GPU ran into a Dash-8 prop (similar technology, same series engine) with the prop rotating at around 760rpm. Externally only appeared to be damaged blades but the anti torque crossmember at the rear engine mount (which is bolted to a centre bracket at the rear of the engine) sheared it's attachment bolts completely, the vertical strut impacted on the underside of the upper fuselage mount, twisted the nacelle and pulled some of the nacelle to spar fasteners. All of the nacelle fwd of the front wing spar had to be replaced.........

I'd imagine the engine will be pulled and sent for inspection which will probably reveal no damage but maybe the airframe suffered more......

[burgervan1]

Non iron

Glad to see you still have the same chip on your shoulder as you had before your contract ended/not renewed in Aer Arann some time ago. For a 'mature' person your posts are somewhat odd on both threads on this subject. But then it dosen't surprise me. Working these days? I along with many of your former colleagues who have now moved on to larger airlines enjoyed and gained good experience in an expanding airline at the time. Personally I'd like to see an official report on what happened before getting excited and placing blame. Time to move on non iron.

Anyway back to the subject..........

[Papa2Charlie]

Thanks for all the useful info on here. I can imagine the crew emerged from the aircraft wishing they had stayed in bed that morning. :} Now the messy business of repairing this begins....

[Flightrider]

What the pictures don't show you is that the aircraft actually stopped a very very short distance from the terminal - the nose is probably less than one metre from the stanchions supporting the pier.

Assuming what happened is very similar to the AAIB report listed earlier, you do wonder what has to happen before operators realise that taxying aircraft around on one engine can have inherent dangers which are all too quickly forgotten in the rush for fuel and engine maintenance cost savings.

[Papa2Charlie]

Hi Flightrider,

From a previous post, it appears the A/C had a total loss of hydaulic fluid and therefore the number of engines running wouldn't have an effect.

Not all airlines are convinced of the savings of single engine ground ops. In some cases it can cause more long term harm than good e.g. oil coking in scav or vent lines in the engine. However, issues such as this are very engine/oil specific.

Ultimately, most airlines need to rely on a) the OEM recs and b) their own engineering judgement. Anywho...I diverge from the event at hand.

Regards,

P2C.

[Airforce1]

To put all you single engine taxing critics to rest... heard today the aircraft was not taxing in on one engine. All you ground staff who were quick to put pics on the net, perhaps can take a trip to your airport security room and view the surveillance tapes. The aircraft had been parked, and than just rolled further slowly afterwards with complete hydraulic failure. Hence just some healthy nicks out of the props. If it was at a faster pace-more damaged would have done to them. Crew not to blame here it seems, just tech prob due to ATR...:zzz:

[non iron]

And what subject might that be Burgervan ?

Deleting the whole " Arann " thread prior to running for cover ?

l was harsh, l agree, and took my comments back because it couldn`t be constructive.

You attacked me personally, it seems for voicing concern over dwindling command experience.

Answer this then;

After audible and visual " low hydraulic fluid" warnings, closely followed by " low hydraulic pressure" warnings, would you, after your plainly extensive and all encompassing ( did you get to see an aircraft de-iced or even hear about it ?) apprenticeship with AA, would you actually point the f%cking airplane at a building ?

l`m sure your present captains enjoy your company as much as the last lot.