Interesting reading all the speculation and expert commentry on the tailboom problem and with the AW139 in general. Seems to me the predecessors of the Bell 412, had major problems with the fin spar cracking at one time also which was not truly eliminated until the advent of cold expansion of fastener holes. Bell recognized a potentially damaging problem and worked long and hard to find a fix. This may be news to all those doomsayers finding fault with the AW139, who I suspect are people not involved with the operation of this heli. I agree that Agusta may have truly miscalculated the forces involved in taxying this large helicopter around using primarily the tail rotor, by not extending the 6 attachment longerons the full length of the forward panels. This large arm coupled with localised heat from exhaust nozzles likely to be affecting/weakening the area immediately behind and below them during taxying and extended hovering. Hang on a minute......didn't the 212 have problems with the baggage bay forward panels delaminating on long line and rescue helicopters!? Yes, and the problem was solved by finding a new and improved bonding procedure to create new 'hot bonded' panels which minimized the problem. Agusta has shifted to new aluminium core composite panels and offers this as a retrofit through BT139-159, but at the customers option/expense. This to me looks as though it will not be the end fix. I think until they go to a full length longeron, the problem cannot be solved through repair or panel replacement. You can bet they are well down the road to finding the end fix as we speak in conjunction with their tailboom supplier. A fix must be found or future sales of this machine are in serious jeopardy. It is interesting to read about the complexities of composite panels from people who have been involved in the repair business for some time, but the problem here is pretty obvious. Every helicopter has had to deal with it at some point during the design stage. The adhesives and processes used on these panels are not new. What seems strange to me is that when I first saw a presentation on the (AB)139 back in I think 2003/4, Agusta suggested there would be no new technology used in the design of the fuselage and tailboom. This ended up being a fully composite aircraft! Only the boffins can explain that one. This aircraft also began it's life as a joint Bell/Agusta product it should be mentioned.
Agusta have some tough decisions to make and fast, no doubt about it. I must say that during the last four years working on this machine, I have found it a breath of fresh air not to have to worry about the next servo change in an oily smelly hell-hole, or the next power section or c-box change with a million AN3C bolts to move, sometimes just to get to a delaminated engine deck, or the next track and balance of the 'greaseless' head and rotor with more rubber and bearings to fail than you can poke a stick at, etc etc. The AW139 is not leaps ahead of the 412 and S76 (Who dreamed up that mess on the roof by the way?!) as an offshore helicopter, it is widely favoured by customers and crews in not only oil support but other roles such as Rescue and VIP. It is a very fast, very powerful and stable platform and is maintenance friendly, with designers for the most part considering the engineers lot as well as the pilot for a change. Once all the hysterical reaction to the tailboom thing goes away, the AW139 will still be out there doing what it does, outperforming the opposition. Good luck with the EC175, Eurocopter.......same aircraft, only 5 years late.
There, I've said my bit. WC
