Leicester City Helicopter Crash

Any RW pilots here: How often during maintenance schedules are bearings in critical components checked?
Is this likely something that has developed over time and should have been 'picked up' or- just sh1t luck?
Pilots perform a fairly rudimentary pre-flight check - looking at oil levels, obvious leaks and generally giving everything a bloody good shake.
Hidden insipient faults such as this one are completely invisible to pilots, and engineers who do a far more thorough 'Check A'.
This fault would have only been detected following a strip down of the tail rotor controls at the gearbox end, which is not a day-to-day occurence.
 
Any RW pilots here: How often during maintenance schedules are bearings in critical components checked?
Is this likely something that has developed over time and should have been 'picked up' or- just sh1t luck?
I worked for an EASA Approved Part 145 MRO maintaining both parapublic and offshore helos. We performed C and G inspections ....to give you an indication

C took 3/4 weeks or several hundred to 1000

G or Heavy took 3/4 months or 5/6000 hours as in complete and utter strip to the bone ...I saw one G insepection of an AS365N3 Dauphin up in Aberdeen ...believe me when I say it was in bits and pieces on the hangar floor. If the company doing inspection does not have the caps in house according to the relevant authorities or OEM approvals, the likes of engines and blades off to those that are approved to. 6/7 times out of 10 the engines will go back to their OeMs either in-country with their facility / reps or back to the home country.

Of note it was mainly for then Eurocopter AS350/AS355/AS365/AS332/SA330 and Sikorsky.S-61N, and S-76A and C models.
In the summer of 2003, Eurocopter issued a new mandate w.r.t full strip down G inspection of the AS365 Dauphin to operators and MROs alike. new mandate suggested continuous inspection rather than have an operators / owners a/c down for AOG fro few months where they be losing money..just spread out the inspection.

You could also measure insepction by year not just how many hours

With the fateful AW169....I doubt , until the accident warranted anything close to equivalent of G or Heavy Inspection as probably would not have flown anything like a few 1000 hours since it left the factory at Verigiate.
Magic question, is when they did they opened up the panels for insepction and was anything found

Also it’s a MUST, a legal requirement to have a Licensed engineer to sign off the maintenance paperwork / release ..preferably one whose licensEd on the type they are inspcting.

Specialist Aviation Services (formerly Police Aviation Services and Medical Aviation Services) In Staverton Airport are the biggest user of AW169 in UK if not Europe. They supply the 169 and pilots plus maintenance to the air ambulance / EMS operators. Recently delivery was to The Children’s Air Ambulance ..I was there at Farnborough ( photo below)
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For reference here’s my photos of the first German reg AW169 .being operated by Wiking Helikotper GmbH at Helitech 2018 in Amsterdam 2 months ago.

Cheers
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Moped wheel bearings have shields on them, but helicopter tail rotor bearings don't?
Aircraft bearings that are exposed to the weather are protected against it, or are designed to withstand it.
The bearing in question was not exposed. If it had been, the deteriorating condition would/should have been picked up.
 

Cutaway

LE
Kit Reviewer
If they were castellated nuts they should have had a cotter pin or similar holding them on.
Wouldn't have been a Cotter.
More likely wired and/or a split pin.
 
Question from an aerodynamics ignoramus, having lost the tail rotor, is an uncontrolled descent inevitable or is just highly likely given the effect of the spin on the pilot's ability to remain orientated and in control?
 
Any RW pilots here: How often during maintenance schedules are bearings in critical components checked?
Is this likely something that has developed over time and should have been 'picked up' or- just sh1t luck?
The bearing is inside the t/r spider assembly so you can’t visually inspect it without a lot of dismantling. If it doesn’t have it’s own service life, it might be replaced/ inspected when the servo jack is removed for service, or when the t/r hub is replaced. The bearing itself looks to be sealed so no maintenance. Might just been a duff bearing or it was damaged when fitted, either way it’s going to be top of someone’s ‘things to do today’ list...
 
Question from an aerodynamics ignoramus, having lost the tail rotor, is an uncontrolled descent inevitable or is just highly likely given the effect of the spin on the pilot's ability to remain orientated and in control?
I'm not RW pilot but, main rotor induces yaw which is countered by tail rotor. My understanding is, without command of tail rotor, only option would be to reduce power to main rotor- slow the spin but increase descent...

I'm sure I'll be corrected by some of the helo pilots on here.
@beefer @BareGrills
 
Wouldn't have been a Cotter.
More likely wired and/or a split pin.
Cotter pin is an American term for what we call a split pin.

I'm not RW pilot but, main rotor induces yaw which is countered by tail rotor. My understanding is, without command of tail rotor, only option would be to reduce power to main rotor- slow the spin but increase descent...

I'm sure I'll be corrected by some of the helo pilots on here.
@beefer @BareGrills
This accident was caused by the tail rotor control driving the blades to maximum pitch. Even with both engines shut down, and in full autorotation, with the tail rotor providing max thrust the end result would have been the same.
 
Cotter pin is an American term for what we call a split pin.



This accident was caused by the tail rotor control driving the blades to maximum pitch. Even with both engines shut down, and in full autorotation, with the tail rotor providing max thrust the end result would have been the same.
Thanks
 
Question from an aerodynamics ignoramus, having lost the tail rotor, is an uncontrolled descent inevitable or is just highly likely given the effect of the spin on the pilot's ability to remain orientated and in control?
Never a RW driver but spoken to a few about this problem. With speed the helo can be basically kept going in a straight line but it will require a "conventional" landing as it cannot be hovered. A notorious example of this was a RAAF HU-1 on a UN peace keeping detachment in Sinai which lost its tail rotor at night with a full load of senior officers from the various detachments. The driver (one should always call them the "driver" - it drives them insane) was able to skid it back on the ground at their base without further damaging machine or occupants. It was reported that several of the passengers refused to fly with anyone other than the RAAF.

There is another option where the machine has sufficient height. The driver immediately (and I mean immediately) dumps the collective pitch and makes like a lead balloon towards the ground. This causes sufficient air flow through the main rotors to spin them up so that at a certain height above ground the driver hauls on the collective lever bring the machine to a near stop and is then able to put it on the ground, normally without too much drama.

With this particular crash, I understand that it was just after liftoff and with the tail rotor driving them at maximum pitch and power then it will overcome any corrective action so consequently the machine had no forward speed when it lost its tail rotor and not enough height for an auto-rotation landing. Game over and lights out is the result.
 
With this particular crash, I understand that it was just after liftoff and consequently the machine had no forward speed when it lost its tail rotor and not enough height for an auto-rotation landing. Game over and lights out is the result.
In this case, dumping the lever wouldn't have affected the outcome. It was a horrible situation that was totally irrecoverable.
 
Totally. We need to stamp reports we agree with our seal of approval.
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But...isn't Arrse Air basically just a FART or are you suggesting that the Arrseratti should be investigating Botty Coughs?
 
The driver (one should always call them the "driver" - it drives them insane)


There is another option where the machine has sufficient height. The driver immediately (and I mean immediately) dumps the collective pitch and makes like a lead balloon towards the ground. This causes sufficient air flow through the main rotors to spin them up so that at a certain height above ground the driver hauls on the collective lever bring the machine to a near stop and is then able to put it on the ground, normally without too much drama.
The procedure above relates to engine failure not tail rotor failure. However the pilot may elect to shut the engine/s down and autorotate to a landing. However this has to be very finely judged and I’ve never seen anyone pull it off in the simulator.

And I was very proud to be called a “driver”
 

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