Turbo for flatlanders

[weilke]

Regardless, can you ballpark quantify the added maintenance/shortened TBO?

In his particular case, it means going from a Lycoming with a 2000hr TBO to a Conti with 16-1700hrs.

In other installations, e.g. the 182T and T182T there is no difference in nominal TBO.

Most turbo owners seem to require either a turbo overhaul or some work on the wastegates/controllers somewhere at halftime. As one put it to me: 'a buck fifty an hour in extra overhaul reserve to get above the bumps'.

The Lycoming turbos have some sinfully expensive parts in the exhaust. Based on the price for the part called 'transition', I have decided that it must be hand-carved from a block of solid rhodium by unionized swiss watchmakers.

 

[denverpilot]

Max climb speed for both airplanes (on which climb rates are published) is ~identical. The biggest factor in time will be the spread between cruise speed and climb speed for the extra few minutes of climb. While in climb and cruise, however, the T version will burn ~20% more fuel than the N/A.

Fair enough. 'Round here the T's get off the ground a bit better. But we've already handled that with 10,000' GA runways, so it doesn't matter much for that either.

 

[wabower]

True, but even though your flat land only extends in threee directions, it's ~4,500' higher than the same flat land here in the sauna.

Back in the day, I played in LTV's pro-celeb in Steamboat every year during July 4 holiday, and always flew with the family to Stapleton before driving the final leg into the hills. We would usually play a final early morning post-tourney round before driving down to Denver for the flight home, and find ourselves departing mid-afternoon. Even though the N/A 210 was capable of doing so, the the takeoff rolls were long and fast. The turbo was a welcome addition for those trips, and for my use it was probably the single best reason for the T vs the N/A.

Fair enough. 'Round here the T's get off the ground a bit better. But we've already handled that with 10,000' GA runways, so it doesn't matter much for that either.

 

[Alexb2000]

Do you have many of those linked picture attachements in your posts, the kind where you upload it onto the site rather than hotlinking it from a different site like flickr ?

OK I figured it out. I have flown some really fast Bonanzas all light weight NA, but this blows any of them away. Check this out:

 

[wabower]

What is the altitude-corrected TAS for the IAS indicated in the picture?

OK I figured it out. I have flown some really fast Bonanzas all light weight NA, but this blows any of them away. Check this out:

 

[wsuffa]

The Lycoming turbos have some sinfully expensive parts in the exhaust. Based on the price for the part called 'transition', I have decided that it must be hand-carved from a block of solid rhodium by unionized swiss watchmakers.

More than just the exhaust.... the wastegate cable on mine is $700+ (teflon lined) and the wastegate cable end is $1000+/-. Those typically don't go bad unless you've got a mechanic that sprays the wrong stuff on in the cable or cable end & gums them up (or destroys the teflon coating). The exhaust system parts can be "rebuilt" ore "overhauled" by a good exhaust shop.

The turbo adds a bit of maintenance, probably a couple of bucks an hour, and a bit of weight. You do have to pay extra attention to the possibility of exhaust leaks prior to the wastegate lest you get the equivalent of a flamethrower in the engine compartment.

 

[Alexb2000]

What is the altitude-corrected TAS for the IAS indicated in the picture?

KTAS bottom of the left vertical tape in the small window reading 195.

 

[Ted]

It counts for a lot, but is only part of the equation, as you should know.

Performance is far more than engine design or operation.

And Wayne has pointed that out quite well.

So those posting that feel so conclusively that a piston turbo isn't worth it in any flight profile, then why do you suppose they are selling so well?

Cirrus SR22T, SR22TN
Beech G36 (announced a factory turbo version) TAT conversion is very popular
Beech G58 (announced a factory turbo version)
Cessna 400, T182T, T206H
Etc.

Any answer works for me except the world is full of stupid people with $500K-2M to spend on a piston aircraft.

I think there are a few factors here, with marketing being the biggest one.

"The turbo version is turbocharged! You can fly higher and faster!"

The local SR22 turbo pilot asked me what's the point in having a turbo if you only fly it at 65% power? Of course, at 1200 SMOH he's on his second top overhaul of his TSIO-550 running 86% power cruise, but he's making his turbos work and earn their keep. Marketing these days is saying that's ok to do, and if you like buying cylinders, then that's fine.

Those of us who understand what makes engines last a long time realize that 86% power is a terrible cruise point won't see as much speed benefit as those who are ignorant (or apathetic) on this point.

I'd also point out that modern turbo installations have a number of benefits over older ones. Wayne's T210 was basically a turbo bolted onto an engine. No intercooling. Most modern turbo installations have intercoolers, which make a significant improvement in altitude performance in most cases. The add-on or upgraded intercoolers available for the Navajo, 340, 414, Duke, etc. happen to be one of the few upgrades out there that provide exactly the benefits stated.

Turbos also are very nice to have in any form once you get used to them. Wayne is being very practical with his points, but also has pointed out that he liked having his T210, just the point that it wasn't faster on the whole. I think the buyers of modern piston aircraft are buying them as tools more than as toys, and as such if they can afford to spend $700k on a Cirrus, what's the extra $50k or so for the turbo version? The cost increase is comparatively small, and if you can afford to spend that much money on that plane, then the added MX is probably irrelevant. You can buy a King Air 200 for that price.

To me, the key to a turbo plane is one that is properly implemented and utilized.

The exhaust system parts can be "rebuilt" ore "overhauled" by a good exhaust shop.

Turbo engines are probably one of the best examples of when to not cheap out on the overhaul. Get a factory overhaul, or else insist on a new exhaust - not rebuilt. I have seen more problems with people who cheap out on the turbo exhausts than anywhere else.

If your exhaust needs to be repaired, just buy a new piece or a whole new exhaust system. It will end up saving you money in the long run most of the time.

 

[denverpilot]

Even though the N/A 210 was capable of doing so, the the takeoff rolls were long and fast. The turbo was a welcome addition for those trips, and for my use it was probably the single best reason for the T vs the N/A.

Yup. Folks get antsy and pull the airplanes off the ground before they're ready in the summertime here. Wheel bearings are cheap if maintained properly. Maybe a touch harder on tires.

It does feel better to launch in "normal" distances versus long takeoff runs, but it's mostly an emotional thing. Max Gross at 85F+ in the NA Skylane feels like it takes forever. Also usually ends up less than 500 FPM.

A rejected TO probably means new brake pads.

 

[Clark1961]

Turbo engines are probably one of the best examples of when to not cheap out on the overhaul. Get a factory overhaul, or else insist on a new exhaust - not rebuilt. I have seen more problems with people who cheap out on the turbo exhausts than anywhere else.

If your exhaust needs to be repaired, just buy a new piece or a whole new exhaust system. It will end up saving you money in the long run most of the time.

The Frankenkota had about 700 SFRM when I bought it. The exhaust had been repaired by Wall Colmonoy (SP?) within the past 200 hrs. It's been doing fine since. I believe they may be one rebuild shop that's okay to use since they basically zero time the part they're working on. Of course they may be the exception that "proves" the rule of your advise.

 

[wsuffa]

Turbo engines are probably one of the best examples of when to not cheap out on the overhaul. Get a factory overhaul, or else insist on a new exhaust - not rebuilt. I have seen more problems with people who cheap out on the turbo exhausts than anywhere else.

If your exhaust needs to be repaired, just buy a new piece or a whole new exhaust system. It will end up saving you money in the long run most of the time.

So the "quotes" in my post were that certain exhaust overhaul shops will call it an "overhaul" but deliver what is essentially a "new", zero-time exhaust. It's more than providing just a piece of pipe, it's delivering something that's indistinguishable from "new".

In other words, I agree with your assessment. The exhaust on a turbo engine requires extra care.

 

[Ted]

The Frankenkota had about 700 SFRM when I bought it. The exhaust had been repaired by Wall Colmonoy (SP?) within the past 200 hrs. It's been doing fine since. I believe they may be one rebuild shop that's okay to use since they basically zero time the part they're working on. Of course they may be the exception that "proves" the rule of your advise.

If you have a shop you're happy with, then obviously that's what matters the most, and it's good to know if you found a good one. I would never tell someone to abandon a shop they are happy with.

What I see happen most of the time on turbocharged engines with low-buck overhauls is that the turbochargers and exhaust systems are reused. This works fine and saves some money in the short-term, no doubt. They then send exhaust parts out for "overhaul", with the affected area repaired. Then at the next annual/100-hour, they discover another exhaust problem. Then the turbo starts acting up and gives out. A high-dollar/FRM doesn't guarantee that it will go to TBO without problems (as your plane indicates), but in my experience it certainly helps.

The local Aerostar owner likes to buy his engines from a low-buck overhaul shop that is pretty well known for doing poor quality work. He also opts to buy the cheapest new cylinders he can.

Right now, his right engine is getting replaced. It's timed out and has factory Lycoming cylinders. Those old Lycoming cylinders have better compression than his 300 SMOH left engine that was done by the same shop with aftermarket cylinders.

 

[Ted]

So the "quotes" in my post were that certain exhaust overhaul shops will call it an "overhaul" but deliver what is essentially a "new", zero-time exhaust. It's more than providing just a piece of pipe, it's delivering something that's indistinguishable from "new".

In other words, I agree with your assessment. The exhaust on a turbo engine requires extra care.

I figured we'd be in agreement.

 

[wsuffa]

What I see happen most of the time on turbocharged engines with low-buck overhauls is that the turbochargers and exhaust systems are reused.

If I'm not mistaken, the Lyc overhaul manual on my plane calls for replacement of the exhaust and TC. That said, those are two things that I'd replace as part of an OH, even if they "look" good.

 

[Alexb2000]

I think there are a few factors here, with marketing being the biggest one.

"The turbo version is turbocharged! You can fly higher and faster!"

The local SR22 turbo pilot asked me what's the point in having a turbo if you only fly it at 65% power? Of course, at 1200 SMOH he's on his second top overhaul of his TSIO-550 running 86% power cruise, but he's making his turbos work and earn their keep. Marketing these days is saying that's ok to do, and if you like buying cylinders, then that's fine.

Those of us who understand what makes engines last a long time realize that 86% power is a terrible cruise point won't see as much speed benefit as those who are ignorant (or apathetic) on this point.
.

Could we be throwing the baby out with the bath water on this one?

Maybe it's not the turbo itself, but all aspects of the aircraft that comes with it. In the Cessna 400 I started dialing it down slowly 75 miles out. Descend with speed brakes. Idle for a few minutes after touchdown, etc. Basically carefully managing the motor because it's so tightly cowled and temperature sensitive. If you want a Ferrari, be prepared to baby it a little, or pay.

Contrast that to the modern "tin" Cessna turbos, they don't take a lot of work to keep in line at all. CHT's stay very consistent and are easy to manage. Generally make TBO without issue.

King Air 200, come on now, why not a Lear? They can be had for $300K

 

[weilke]

So the "quotes" in my post were that certain exhaust overhaul shops will call it an "overhaul" but deliver what is essentially a "new", zero-time exhaust. It's more than providing just a piece of pipe, it's delivering something that's indistinguishable from "new".

Just replaced an exhaust. They dont call it 'overhaul' as there is no 'overhaul manual' for exhaust parts. They actually call it 'repaired'. If you look closely, you can find a little tab from an old exhaust they received as a core welded to one of the internal baffles, one molecule is enough to make it a repair. If they called it 'new', they need a PMA, if they call it 'overhauled' they need a manual to follow. They call it a 'repair', all they have to do is adhere to some generic rules about workmanship.

 

[Ted]

If I'm not mistaken, the Lyc overhaul manual on my plane calls for replacement of the exhaust and TC. That said, those are two things that I'd replace as part of an OH, even if they "look" good.

I haven't looked at the overhaul manual, but that sounds accurate, and a good idea.

Could we be throwing the baby out with the bath water on this one?

Maybe it's not the turbo itself, but all aspects of the aircraft that comes with it. In the Cessna 400 I started dialing it down slowly 75 miles out. Descend with speed brakes. Idle for a few minutes after touchdown, etc. Basically carefully managing the motor because it's so tightly cowled and temperature sensitive. If you want a Ferrari, be prepared to baby it a little, or pay.

The "I didn't buy this plane to go slow" mentality isn't new, nor are marketing departments that recommend abusing engines to make the numbers they want to show their customers. So I'd agree. Beechcraft put underpowered engines in the Duke (it really should have had the 450 HP TIGO-541s rather than the 380 HP TIO-541s), and that certainly didn't help the reputation of the TIO-541s.

If you want to go fast, then you should run at your high power setting. It's your plane and you pay the bills. Typically, what we found is that people would do this for a while until they got sick of paying high maintenance bills, and then would dial it back a little and cut their costs significantly. Or else they'd buy a turbine.

Contrast that to the modern "tin" Cessna turbos, they don't take a lot of work to keep in line at all. CHT's stay very consistent and are easy to manage. Generally make TBO without issue.

There's nothing new about a piston airplane that benefits from careful engine management for longevity purposes. I think the difference is that the legacy aircraft no longer have a marketing department pushing highly inefficient speeds, and today's owners might be more concerned with longevity. Or maybe they aren't, I see enough people with legacy planes who fly the pants off of them. Of course, most of them also need frequent top overhauls and have engines that don't make TBO.

King Air 200, come on now, why not a Lear? They can be had for $300K

Good point!

 

[wsuffa]

issue.

King Air 200, come on now, why not a Lear? They can be had for $300K

If you're going that far, take it a step further and get a Saberliner. Or maybe pick up Hef's DC-9 on the cheap...

 

[Ted]

If you're going that far, take it a step further and get a Saberliner. Or maybe pick up Hef's DC-9 on the cheap...

I'd go for the Lear 24. Ultimate in excessive speed and noise.

 

[Everskyward]

Interesting, I would never have thought of buying a turbo in order to get more speed. In our case it was either because we operated out of a high DA area and/or the turbo was needed for the work operation we were engaged in. I didn't feel that the fact that the airplanes were turbocharged made them touchy to operate and maintain but then I really have nothing to compare it to.

 

[Ted]

Interesting, I would never have thought of buying a turbo in order to get more speed. In our case it was either because we operated out of a high DA area and/or the turbo was needed for the work operation we were engaged in. I didn't feel that the fact that the airplanes were turbocharged made them touchy to operate and maintain but then I really have nothing to compare it to.

You were also working to get a job done rather than for personal transport. I've noticed that the companies that operate airplanes will tend to have more reasonable operating policies, since high maintenance costs reduce their bottom line.

 

[Everskyward]

You were also working to get a job done rather than for personal transport. I've noticed that the companies that operate airplanes will tend to have more reasonable operating policies, since high maintenance costs reduce their bottom line.

That is true. We didn't operate at much more than about 65% at cruise but since there was a lot of maneuvering involved speed was not important and could be a detriment. We did have those long climbs up into the flight levels, however.

 

[Sac Arrow]

You can make the argument that you can fly a turbo for more speed on long trips. I got a turbo for two reasons - flying in and out of high DA airports, and for more speed for trips 200+ NM when it's worth it to get above 12K. I never pushed it over 65% cruise, but being able to maintain 65% power at above 12K is huge.

I don't fly one anymore. The added speed wasn't worth the maintenance costs, and these days most of my flying is below 5,000 feet.

 

[Ted]

That is true. We didn't operate at much more than about 65% at cruise but since there was a lot of maneuvering involved speed was not important and could be a detriment. We did have those long climbs up into the flight levels, however.

I was figuring that since most of what you were doing was mapping you were probably running at an economy cruise. In the Navajo we run a 75% power cruise since our passengers are in a hurry. Of course, there are Navajo pilots that, when I try to pull the levers back from 40"/2400 RPM say "What're you doing that for?"