Especially nowadays, with national CAAs becoming little more than EASA field offices, the level of technical expertise in the CAAs is low and sinking lower every day.
Yet another reason for keeping the authorities out of the details of the condition of the engine.
With a condition based system, it is no longer enough to verify the log book of the engine, the log book does not say anything meaningful about the condition. You have to report the condition to the authorities to verify airworthiness. It will be like these car controls we have, only 100 times more bureaucratic and detailed. I don’t think you understand the consequences of what you are asking for.
I don’t understand where that idea comes from. Most of the aircraft and its components are maintained “on condition”. There is a (more or less detailed) schedule of inspections that have to be performed, typically as part of flight-time (50/100/etc. hrs) and time-based (annual) maintenance. Fixed life / TBO for components is the exception, not the rule.
All “on condition” maintenance requires is that there is a sensible schedule of inspections, somebody competent making these inspections, and a signature by the competent individual (or supervisor) that the inspections were performed with no discrepancy found. Exactly as every other bit of the annual or maintenance check. One signature on the RTS is all that counts and is ever checked by the authority (checks of the maintenance organisation are separate from airworthiness of an individual aircraft).
Another example – topping up and changing the engine oil is essential for continuing airworthiness of the engine – if that does not happen, it will die quite quickly. And yet, no authority feels the need to monitor that in detail. The most you get is a tech log with oil level information, but I have yet to see the requirement to report that to the authority, and it is only mandatory for commercial ops.
I was talking with my maintenance organisation yesterday. There is a worldwide shortage of a particular battery for a well known airframe. This is recommended to be changed after a certain number of years. They spoke to the manufacturer who can’t give an update on availability but said of course it doesn’t matter it is only a recommendation. They couldn’t believe that this maintenance organisation will have to start grounding G-reg versions of this aircraft if the part isn’t available soon. They all agree it is silly but the UK maintenance organisation has no discretion.
All “on condition” maintenance requires is that there is a sensible schedule of inspections, somebody competent making these inspections, and a signature by the competent individual (or supervisor) that the inspections were performed with no discrepancy found. Exactly as every other bit of the annual or maintenance check. One signature on the RTS is all that counts and is ever checked by the authority (checks of the maintenance organisation are separate from airworthiness of an individual aircraft).
What is a sensible schedule of inspection of an engine that has run 4000 hours since new and that has gone through no overhaul ? Nobody knows. Nobody knows what to inspect, nobody knows how to inspect. To know this, you would have to at least know the condition of all previous inspections, because some engines live good lives, other live terrible lives. An engine is not just a component where you can simply clean off the dirt and take a measure. Modern car engines, modern jet engines, modern marine engines, modern train engines, modern anything – engine has made condition based maintenance possible, effective and accurate because they are full of sensors that take measurements, they log these measurements, and tell you when something is wrong and exactly what is wrong. Data is collected and sent to the manufacturers for analysis. Software controlling these engines are updated based on the collected data. A Lycoming is not a modern design, it is a design from the 40-50s. It has nothing of the basic technology needed for effective condition based maintenance. A Lycoming is designed for quick and easy overhaul, in the field if necessary. A Rotax 912i has what it takes. If BRP wants to take full advantage of this, still remains to be seen.
I just don’t see the point of this on ancient technology, a fully mechanical device like a Lycoming. It doesn’t even have computer controlled engine management. It makes no sense to me.
Nobody knows
I guess people like Mike Busch disagree with you
it is a design from the 40-50s. It has nothing of the basic technology needed for effective condition based maintenance
I may be wrong but things like an EDM700 were certified slightly after the 50ies.
But then again, filter cutters probably were.
LeSving, I am very happy that you do not work for any CAA because what you say goes even beyond the worst I’ve heard from that corner. On-condition maintenance of piston engines has been done for decades with very good results. You think you are smart enough to build your own experimental which will be “airworthy” but you do not accept that trained maintenance personnel can reliably determine the airworthiness of an engine.
Statistics do not show any significant accident rate due to post-TBO piston engines. Examples like the famous crash in Switzerland were so obviously unairworthy that they only show that the paperwork focused Part 145 supervision in EASA land is defunct. No person I know in aircraft maintenance would have signed off that Piper in Switzerland and the most amazing thing about it is how long this airplane actually flew.
If you take a TIO-540 or TSIO-520 in a typical installation, you can render that engine unairworthy very easily within a couple of hundred hours. Actually in most installations you are guaranteed to do that (e.g. Cessna P210 and Piper PA46 Malibu).
I was talking with my maintenance organisation yesterday. There is a worldwide shortage of a particular battery for a well known airframe. This is recommended to be changed after a certain number of years. They spoke to the manufacturer who can’t give an update on availability but said of course it doesn’t matter it is only a recommendation. They couldn’t believe that this maintenance organisation will have to start grounding G-reg versions of this aircraft if the part isn’t available soon. They all agree it is silly but the UK maintenance organisation has no discretion.
What aircraft is this and what is the battery?
It can’t be a trade secret if it is a “worldwide shortage”.
One of the Cirrus. It is the second battery I believe.
In the absence of useful information, my guess is that the battery is likely to be a Gill, which everybody and their dog is changing for a Concorde because they are much better in every way.
On the N-reg, on a “simple” plane like a Cirrus, you just change it. Only the most anally retarded FSDO will say otherwise, and a number of US pilots got a written FSDO opinion that they can be changed as a Minor mod (A&P signoff because it’s outside pilot privileges). I got mine done years ago (signed by an IA, twice in fact because it was replaced after about 6 years). There are plenty of A&Ps who can’t read and write (the US has an even bigger adult literacy problem than the UK) so Concorde have loads of “marketing” STCs to keep these people happy. I had a chat with them about this recently and educating installers about regs which the installer should know is their biggest issue.
On a G-reg, you do it off the books and if the CAMO disagrees, take the plane somewhere where they just quietly swap it over.
The CAA doesn’t prosecute companies which have done things which have killed somebody, so they aren’t likely do go after somebody who changed a battery for a better model.
Of course the issue could be something much more complicated in which case the original story is different………
Peter, were you trying to be offensive in that post?
