EC-135 ARIS Pots Question

[eurocopter beans]

Can anyone tell me the best way of visualy inspecting your pots if you suspect the bellows have cracked. Apart from the whole leaking fluid thing. I know the 'pendulum rod' disappears but where is this found on the pot assembly?? Do you include this inspection in your walkaround?I know its staring me in the face but any answers appreciated.

[Mr_G_Box]

ARIS

The rod is viewed from underneath. It is in the centre of the ARIS mount, however unless the cabin inspection ports are incorporated on your aircraft you will have to get an engineer to remove the cabin trim/soundproofing to check for sure that the unit has failed.

Mr G Box

[eurocopter beans]

Thanks,

Has one ever broken on you in-flight, is it immediately and definitely noticeable or is it possible to fly around without noticing one has gone u/s, i think my arse is insufficiently tuned to know for sure.

[NLJ]

Dear Mr Beans,

The easiest way to check your ARIS pots is to look for a gap between the collar at the top and the body of the pot. If there is no gap then your pot is u/s. And yes, I can from personal experience, confirm that they can go in flight. The change in noise and vibration is immediately obvious. Think riding down a cobbled street on a bike on just the wheel rims you'll get the idea.

NLJ

[QTG]

Depends which one goes as to how it feels. Last one that went on me I only discovered on the daily inspection at the end of the day's flying. Others have been immediately apparent.

[Revolutionary]

The gap NLJ is talking about is hard to discern, at least on two out of the four mounts. One of our mechanics measures the gap width in a tactile way by inserting his credit card into each gap, rather than trying to look at it. If it fits, you're good.

[Brilliant Stuff]

We use a small mirror to have a good look round each ARIS pod, in the past we went through a whole gaggle of the things but then they found a manufacturing error and the beefed the things up. We haven't had one go since.

Another test I was told was to fly at 60kts and pull up the nose which should give a pronounced cobble street feel.

[tecpilot]

Some good hints here still described.

Encountered an in-flight complete failure, the liquid sprayed out, the sight glass in the cabin and the airframe outside behind the vent full of liquid pearls after landing. Heavy vibrations above 100ktn suddenly within one second turned me to a safety landing. At first i thought about a heavy m/r damage

Be carefull, but EC allows 20h of operation with a damaged ARIS but with max speed 100kt. No problem, but not so good feeling i admit.

Took the ship back home at darkness with 90kt IAS and 30kt head wind I will never forget the trip.

[Mark Nine]

Having replaced around 20 ARIS pots, I feel qualified to comment on some of the posts on this thread.

• The Eurocopter prescribed airtest is 100Kts straight and level and then a sharpish nose up. A collapsed ARIS pot will give you a hammering effect.
• The credit card check during a check 'A' went out years ago. The minimum gap in the emergency stop ring is now a 4 point average of 0.1mm which is physically impossible to check with the eye and is smaller than a credit card.
• The pot bellows are filled with a water/glycol mix and the later dash numbers have the dye to aid identification, (this was put in because lots of reported collapsed ARIS pot turned out to be condensation collecting on the perspex bottom cover). You should not find any oil in the vicinity of a collapsed pot.
• Yes, the center plunger on the bottom of the pot, (with the crossed lockwire), will be 'sucked' up into the pot if the bellows are broken. This the most accurate check for a collapsed pot, but don't be fooled by the brown deposit which collects on the end of the plunger.
• The most likely to fail is the left rear followed by the front right.
• With a collapsed pot, you used to be able to carry on for another 10 flying hours, provided you checked the other 3 before flight and were limited to 100Kts. I'm not sure this is still the case.
• A good Engineer can change one in 3 hours or 2 if he has a hand!

Hope this helps

[Droopy]

To answer the original question, you either have to pull the ceiling or pay to have the transparent inspection panels fitted; it's the only way to be certain. It's a lot of downtime or money to address a poor design..

[swenap]

I must say that after replacing a similar number of ARIS pots to Mark Nine over the last 7 or so years I can't help but feeling that Eurocopter really need to sort their act out and fix the problem once an for all. From memory they are on design mk3 at the moment and still failing more frequently than ever. I've even know of at least 2 PAN calls from newby 135 pilots who thought the blades were going to fall off after a pot let go.

There is also a rumour that a UK based operator has designed a program that can pridict a failure of an aris pot to within 20hrs based on location and flight hours and pre-order a new one to minimise down time

Come on Eurocopter sort it out.

[eurocopter beans]

Thanks guys, great inputs. Especially like the 100kt pull up test, where did you get that? Makes sense. I did my training through ECD and never heard that. Its funny how these tricks of the trade get around, if anybody has any more 135 'tricks of the trade' please share! (flying in turbulent conditions etc). Again, thanks for the help.