Engine overhaul time extension?

[av8tr1]

Anyone ever heard of a company operating under 135 getting an extension for time to perform an engine overhaul for multiple aircraft or even just one?

This came up in a conversation where a company didn't have the money to do the required overhaul and wanted to keep flying past the TBO. I'd never heard of this. I thought TBO was a hard deck. NO going over.

 

[Roger Roger]

The only thing that's mandatory is what's written in your ops spec (unless there's an AD limiting it). Doesn't matter if the manufacturer has 2000 hours written in their service information, if you can get your Feds to put 4000 hours in the D101 you're good to go. That said any fed is going to need pretty solid data (like extensive operational experience, teardown results, etc) to write in anything more that about 200 hours over the manufacturers recommended number. You can also do case by case one-time extensions.

All that said, if a 135 doesn't have the money to do a scheduled engine overhaul, then IMHO they don't have the money to be operating that airplane and I doubt they're taking good care of it. I've gotten extensions for timing of engine changes relative to our busy season but always when we already had an engine on the floor or on order.

 

[JeppUpdater]

The place I was CP at had extended their Pratt overhaul times from the factory 3600 hours to 8500 hours, but this was with a lot of experience, data, and regular borescope inspections and oil analysis at every 200 hour inspection. It took years for them to hit that point, and the 8500 was a rock solid limit with zero flexibility (I saw them yank an engine with 8400 on it because it wasn't going to make it though the holiday season). We also had the limit lowered to 8000 while I was there after a couple of blade separation incidents.

But as Roger said, a company without the money for an engine overhaul has no business operating that plane at all and I can't see any PMI worth his or her salt letting them use finances as an excuse.

 

[Roger Roger]

The place I was CP at had extended their Pratt overhaul times from the factory 3600 hours to 8500 hours, but this was with a lot of experience, data, and regular borescope inspections and oil analysis at every 200 hour inspection. It took years for them to hit that point, and the 8500 was a rock solid limit with zero flexibility (I saw them yank an engine with 8400 on it because it wasn't going to make it though the holiday season). We also had the limit lowered to 8000 while I was there after a couple of blade separation incidents.

But as Roger said, a company without the money for an engine overhaul has no business operating that plane at all and I can't see any PMI worth his or her salt letting them use finances as an excuse.

I should have also said that turbines are a whole different animal than recips. Usually turbine manufacturers have very specific procedures in place for getting TBO extensions and somewhere have a rock-solid limit.

 

[av8tr1]

Yeah it's a PT6. Company has been fined for failing to perform inspections in the past.

Not a company I work for or would want to. Finances are specificly the issue in this case. But was shocked to hear that an extention was an option the FAA would even consider.

 

[Roger Roger]

Yeah it's a PT6. Company has been fined for failing to perform inspections in the past.

Not a company I work for or would want to. Finances are specificly the issue in this case. But was shocked to hear that an extention was an option the FAA would even consider.

Pratt has very specific procedures for extending engine TBO 500 hours at a time. With MORE and others you can get those 8000+ hour intervals that jeppupdater mentioned. But like I said with a turbine there's a way it has to be done.

 

[trafficinsight]

Lycoming has a service bulleting outlining TBO extension for the IO-540-AB and AC series in frequent use, but in my experience you had cylinder problems well before then anyway.

Sent from my XT1254 using Tapatalk

 

[knot4u]

I've never had to deal with the FAA regarding extending TBO or getting an extension for an engine, but we have gotten time limit extensions or deferrals from the manufacturer before for some inspections and life limited parts. All of the Ops Specs I've dealt with state that we'll maintain the aircraft according to the manufacturers recommendations, if we get a disposition for a certain item from the manufacturer we're good to go. Normally these dispositions would be given due to parts/resources being unavailable, not because we couldn't afford to comply. In order to get an MEL extension the local FSDO wanted some kind of proof that parts had been ordered and were not going to get to us before the MEL was going to run out before they would grant the extension. When I worked mobile support for TFE-731 engines I came across some very shady operators, if their MSP account wasn't in good standing we wouldn't even open a work order, or we would require a deposit before we'd start, the company had been burned too many times in the past. For an industry that supposedly requires impecable integrity it sure seems like aviation, 135 charter in particular, attracts an inordinate amount of scoundrels.

 

[av8tr1]

For an industry that supposedly requires impecable integrity it sure seems like aviation, 135 charter in particular, attracts an inordinate amount of scoundrels.

Truer words have never been spoken.