The PA46 and the TBM seem to be maintained very differently even though their systems are similar. For the PA46 I think most turbines are run on condition past TBO besides much other maintance on condition. You see more and more Meridians for sale over TBO etc. Also except some brand new M600 nobody seems to be on any engine programms etc.
On the other hand it seems to me that most TBM owners maintain them like a jet. I have no answer why that is the case but it seems to be a tradition, owners maintain planes in a certain way, they buy the engine programms, the used market expects the planes to be maintained in that way, the maintenance companies do it that way and the circle closes.
After all the main reason to buy a PA46 turbine is money. If it was no issue at all 90% of the ownera would probably get a TBM. But the PA46 forum is full of owner reports who did usually retire and then sold their TBM in exchange for a Meridian or similar as they could no longer justify the cost of the TBM.
ELA2 is not applicable to N-reg. A TBM could certainly be run on FAA Part 91. The advantage would be not so much on the engine maintenance (which I guess would not change) but on everything else which is pointlessly done on the Annual (see the link to the other thread).
in the case of TBM, it is way over 2000kg….
Antonio wrote:
Since ELA2 is max MTOW 2000kg, the associated alleviations do not apply.
well… in theory a 1999 kg Jetprop would be ELA2?
thank you all for the answers. I see that More company offers the following: “instructions for Continued Airworthiness” for pt6-64. Is not an STC but. according to them, it could potentially extend the TBO to. 8000 hrs. Anyone has any idea about that?
We did that e.g. here and the view seemed to be that, N-reg, you could do it, but almost nobody does due to the effect on resale value.
Also, and this is the biggest issue with GA maintenance in Europe which drives most owners to using a company, you would need your own facility i.e. a hangar and a freelance engineer to do the work. None of the turboprop maint companies would touch this with a bargepole (I did ask one I knew well about it).
Since ELA2 is max MTOW 2000kg, the associated alleviations do not apply. In theory you could still go around the OEM recommendations, but in practice it is very difficult, especially for a one- aircraft operation. For a fleet operator, using historical reliability data you could in theory and progressively extend the interval, but I do not know any fleet operators of these types.
The “fleet” concept is important since it ensures a controlled environment. When you have multiple individual operators with wildly different, and often very low use, operational profiles, it is more difficult to have benevolent one-size-fits-all intervals.
I wonder: in EASA land is it possible for private operators of the likes of TBM (with PT6-64 and a TBO of 3500 hrs) to operate “on condition” above TBO?
This is not meant to say the design is good: only that its safety impact is minor. Then the push for a fix is more a commercial matter.
Aveling wrote:
Considering we’ve just been discussing the very poor quality of software in electric aircraft, It’s re-assuring to see this kind of thing going on in ‘traditional’ aviation as well.
I for one do not think we are discussing the same thing:
The whole idea is not to have an unplanned flight termination which will be, in this context, the main safety-impacting event.
I don’t have the background on the PT-6, but definitely this particular incident is a problem detected during scheduled maintenance which is what scheduled maintenance is for. Inspections intervals have been planned precisely to avoid a safety impact. Perhaps there were a few in-flight shut-down events originally driving this required inspection?
Even if it would not stop an inflight gearbox damage it would surely show up in the chip detector driving further inspection in resulting on removal of the engine from service without a major safety event.
So by design logic (either inspections or chip detector functionality) , the problem is driven out of the safety realm , which is exactly what we want.
This was not the case in the A400M or Pipistrel Alpha-Electro.
What we are discussing here seems mainly a cost and reliability issue, not a major safety concern: whole different games.
