Sort of.

The PT6 has the intake at the rear, exhaust at the front, so the OVERALL flow is reverse of plane direction (except in pusher configuration like the Piaggio). Ironically, the reverse flow combustor in the PT6 actually has the air moving front to rear.

The only part of the TPE331 that is reverse flow is the annular combustor. Outside of that, the air generally moves front to back (except in pusher configurations like the MQ9 Reaper).

So it is correct to say they both have reverse flow COMBUSTORS, the PT6 is generally mounted so that it is overall reverse low and the TPE331 is generally forward flow.

Mike C.

What terminology distinguishes the general flow through a PT6 versus a TPE331?

The flow is radically different, the PT6 is back to front, the TPE331 is front to back.

What is the term you would use for that?

I'd call it a "reverse flow engine". This will allow you to diligently maintain the terminology purity of "reverse flow combustor", which is just one part of the engine, not the overall engine itself.

Mike C.

My plane came with Aerox masks and they are quite comfortable. The key is that you can inflate or deflate the harness to get just the right tension. Highly recommend.
https://www.aerox.com/4110-725-quick-do ... -headgear/

My plane came with a fully redone interior. The seat backs are lower than others I've seen. It really opens up the cabin. Here's a picture I took when I replaced the overhead lights with LEDs so that was there I was focusing the shot.

That upgrade also modernized the interior by having much brighter and cooler (both thermally and color-wise) interior lights.

What terminology distinguishes the general flow through a PT6 versus a TPE331?

The flow is radically different, the PT6 is back to front, the TPE331 is front to back.

What is the term you would use for that?

I'd call it a "reverse flow engine". This will allow you to diligently maintain the terminology purity of "reverse flow combustor", which is just one part of the engine, not the overall engine itself.

Mike C.

Hey Chris, anyway you can publish your LED bulb part numbers as a service to humanity.

Mike

just say the engine is installed backwards.

Beechtalk is the only place people can get offended on behalf of an engine.

Hi Mike!

Happy to help. I bought them from here: https://aircraftlighting.com/products/l ... ing-light/

It's the L1309W (W is for warm). I believe they also have a cooler color option but my wife likes her lights on the warm side (decries pure white or blue tinged as being too "Battlestar Galactica"). I replaced all of the cabin lights plus the two that shine on the instrument panel from above and just behind the flight deck seats. I never figured out how to open the two at the front of the flight deck ceiling next to the air vents but have never used those lights anyway so stopped trying.

She must be cool if she knows Battlestar Galactica.

CJP reached out to Williams and the answers they got are concerning. They foretell a pretty sizable increase in 2025.

Williams had the usual litany of excuses. Labor, materials, vendors increasing. Oddly, they mentioned carbon steel going up in price (that's under $1/lb, can't be more than $300 of it in an engine). Raw materials is a red herring.

Williams said they had hoped the increase in 2023 would have been sufficient to avoid a big increase in 2024, but obviously that wasn't true. They said in hindsight they should have increased prices more in the past so this year wouldn't be so large. Basically, they apologized for not raising prices earlier. Gee, thanks.

Williams said the increase for 2024 was going to be larger but Textron pressured them to make it lower. Can you guess what that means for 2025? Yup, another large increase if Williams thinks they are already being generous in 2024. Textron views the TAP program price as a potential negative factor in sales, and they should.

They also said there is nothing they can do, they have to remain profitable. This is incongruent with the fact Textron got them to moderate somewhat, so there is something they did do. The "nothing we can do" excuse falls flat and is posturing in the discussion.

I would expect all FADEC FJ44 engines to be over $500 in 2025. Maybe the smallest non FADEC ones will be just under, but only barely. My prediction is a 14% increase. That would make the rates:

CJ: $477
CJ2: $529
CJ2+: $524
CJ3+: $536
CJ4: $559

I would also budget out increases at about 3X inflation for the foreseeable future. 2024 was 5X inflation.

The Williams contract used to have a CPI escalator clause, that payment increases would be limited to CPI-W. As you might expect, that went bye bye very quickly after Williams enticed the OEMs to use their engines. Every 5 years, Williams can change your contract terms. They never move in your favor. If you don't like them, your only option is to stop payments and "lose" all the "value" you paid into the program.

The Williams program was never structured as a balance unlike some programs (ProParts at Textron, or even some engine programs). It is money that instantly vaporizes relative to your account.

CJ3+ engine pair over a full overhaul period (5000 hours) at 2025 rates will be about $2.7M. That's a lot to pay for two HSI and two OH.

Mike C.

Why doesn't Pratt make a similar engine and sell it as an STC for 525's?

Because they can’t build enough engines as it is, we have a client with a new Phenom 300E with an engine problem, it’s been down for months, they just got the loaner last week and we were lucky to get it.

Meanwhile, back in JT15D land, we're not having those kind of problems.

The Mustang fleet is having loaner shortages as well.

Mike C.

CJP reached out to Williams and the answers they got are concerning. They foretell a pretty sizable increase in 2025.

Williams had the usual litany of excuses. Labor, materials, vendors increasing. Oddly, they mentioned carbon steel going up in price (that's under $1/lb, can't be more than $300 of it in an engine). Raw materials is a red herring.

Williams said they had hoped the increase in 2023 would have been sufficient to avoid a big increase in 2024, but obviously that wasn't true. They said in hindsight they should have increased prices more in the past so this year wouldn't be so large. Basically, they apologized for not raising prices earlier. Gee, thanks.

Williams said the increase for 2024 was going to be larger but Textron pressured them to make it lower. Can you guess what that means for 2025? Yup, another large increase if Williams thinks they are already being generous in 2024. Textron views the TAP program price as a potential negative factor in sales, and they should.

They also said there is nothing they can do, they have to remain profitable. This is incongruent with the fact Textron got them to moderate somewhat, so there is something they did do. The "nothing we can do" excuse falls flat and is posturing in the discussion.

I would expect all FADEC FJ44 engines to be over $500 in 2025. Maybe the smallest non FADEC ones will be just under, but only barely. My prediction is a 14% increase. That would make the rates:

CJ: $477
CJ2: $529
CJ2+: $524
CJ3+: $536
CJ4: $559

I would also budget out increases at about 3X inflation for the foreseeable future. 2024 was 5X inflation.

The Williams contract used to have a CPI escalator clause, that payment increases would be limited to CPI-W. As you might expect, that went bye bye very quickly after Williams enticed the OEMs to use their engines. Every 5 years, Williams can change your contract terms. They never move in your favor. If you don't like them, your only option is to stop payments and "lose" all the "value" you paid into the program.

The Williams program was never structured as a balance unlike some programs (ProParts at Textron, or even some engine programs). It is money that instantly vaporizes relative to your account.

CJ3+ engine pair over a full overhaul period (5000 hours) at 2025 rates will be about $2.7M. That's a lot to pay for two HSI and two OH.

Mike C.