Why is my mechanic so against a turbo?

StraightnLevel said:
Can you expand on this a bit?
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I should of been more explicit. Dan Thomas explained it well. Just to add:

What I saw and dealt with was pilots yanking the throttle around too much. Over boosting on take offs and yanking the throttles back 10 inches to start descending. Company standard procedure at companies I worked at was when reducing power, starting off with reducing MP 3 inches 5 minutes before starting the descent, then 1 inch a minute. We would get new hires that never flew turbo charged engines then treat them like they were in a 152 and go from cruise throttle setting to idle to descend. Improper procedures will cause cracks in cylinders. I might have done a couple in myself...

I never flew a manual wastegate, everything I was in had an automatic wastegate, but I can see that improper procedures with that would cause damage as well.
 
If you need to fly above 14000 on a regular basis, get the turbo.

If you’re only going to fly there occasionally, don’t bother, a normally aspirated plane can fly up to the flight level and beyond, it’s just going to take a while to get there.
 
RyanB said:
People often forget the difference of 130ktas to a 160ktas is a matter of a few minutes. A piston single vs another piston single will hardly ever gain an hour, much less a couple. I agree.
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I'm having trouble with this statement.

If I'm flight planning from, say, Houston to Charlotte, are you suggesting that a M20M or SR22T will only be a few minutes faster than a C150? Maybe there's something I'm not getting, as I'm new to this process, but.....?
 
StraightnLevel said:
I'm having trouble with this statement.

If I'm flight planning from, say, Houston to Charlotte, are you suggesting that a M20M or SR22T will only be a few minutes faster than a C150? Maybe there's something I'm not getting, as I'm new to this process, but.....?
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If I may speak for him...he is saying a NA M20M/SR22 will only be a few minutes slower than a turbo version of the same aircraft.
 
robin ardoin said:
If I may speak for him...he is saying a NA M20M/SR22 will only be a few minutes slower than a turbo version of the same aircraft.
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It's mostly bragging rights to go +200 mph....but yes the time difference isn't huge. The real advantage is to "top" weather. Some of the smaller weather systems can be topped at 18,000 feet and the turbo is nice for that.
 
As for weather, especially convective, the absolute worst altitudes are those which most turbo planes operate which is mid teens through mid twenties. Just something to consider.
 
robin ardoin said:
If I may speak for him...he is saying a NA M20M/SR22 will only be a few minutes slower than a turbo version of the same aircraft.
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I get that, and aside from the ability to manage differing wind at different altitudes, this makes sense. However, what I was responding to was:
RyanB said:
... the difference of 130ktas to a 160ktas is a matter of a few minutes. A piston single vs another piston single will hardly ever gain an hour
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How does that math work? 30 ktas over 800 nm makes only a few minutes' difference?

Hence, my question.
 
StraightnLevel said:
I get that, and aside from the ability to manage differing wind at different altitudes, this makes sense. However, what I was responding to was:

How does that math work? 30 ktas over 800 nm makes only a few minutes' difference?

Hence, my question.
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When these kind of numbers are discussed, it's a perfect example of how math can be used to justify pretty much whatever argument someone wants to make. Plus, there's a lot of subjectivity too.

If a faster airplane saves 30 minutes, is that basically irrelevant, or is it significant? How much is that worth?Depends on you.

If a faster aircraft also has more range and lets you skip a fuel stop, that's an easy hour faster just based on the stop alone.

A faster airplane will be affected less by headwinds than a slower one. (And also, percentage-wise, less by tailwinds too).

So, anybody can spin the numbers any way they want to support their side.
 
RussR said:
When these kind of numbers are discussed, it's a perfect example of how math can be used to justify pretty much whatever argument someone wants to make. Plus, there's a lot of subjectivity too.

If a faster airplane saves 30 minutes, is that basically irrelevant, or is it significant? How much is that worth?Depends on you.

If a faster aircraft also has more range and lets you skip a fuel stop, that's an easy hour faster just based on the stop alone.

A faster airplane will be affected less by headwinds than a slower one. (And also, percentage-wise, less by tailwinds too).
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Well said - and that matches what my thinking is coming up with.

I guess if your average flight distance is 150 nm, your time spent on pre-flight, planning, and taxiing is more relevant than cruise speed. If you're doing long distance XC, it matters.
 
weilke said:
- The difference in speeds was not transformational. You can burm more fuel to fly faster at altitude, but there is no magic to it
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I burn the same fuel for the same IAS down low or up high. But at 17,000, my TAS is about 40 knots higher than my IAS.
 
Checkout_my_Six said:
Turbo's don't burn up cylinders. Poor fuel flow (mixture) management burns up cylinders. It happens with or without a turbo.
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Yeah. Yes. (Yeah sounded a little ****ty in retrospect and wasn’t intended) And pilots generally have control of the fuel flow. That’s why I said pilots burn up cylinders.

I think we are in agreement.
 
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Timbeck2 said:
I could buy 4 of my airplanes based on original price in 1970 for the cost of just the engine today.
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In another few years the cost of a tank of gas might be what it costs you for the engine today.
 
RussR said:
If a faster airplane saves 30 minutes, is that basically irrelevant, or is it significant? How much is that worth? Depends on you.

If a faster aircraft also has more range and lets you skip a fuel stop, that's an easy hour faster just based on the stop alone.

A faster airplane will be affected less by headwinds than a slower one. (And also, percentage-wise, less by tailwinds too).
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If a faster airplane costs twice as much per mile, overall, including increased fuel burn, maintenance, engine and prop reserves, and insurance, is it worth it to you?

Far too many people take the money they have available and spend it all on buying the airplane. Then they can't afford to feed it or fix it. So it sits and rots, or is sold at a loss.

Buy something that fits your budget, and take seriously the warnings here about costs. Wishful thinking gets too many folks into trouble. Buying the airplane is only the first little bite out of your bank account.
 
Grum.Man said:
You’d have to do a lot of serious cross
Country trips to justify a turbo. What type
Of plane are you looking at? Maybe there is a different model that provides the same capability as the turbo model you are looking at. For example a 550 powered Mooney probably provides similar or better performance than a turbo 231. In my opinion if you are doing enough cross country work to justify a turbo you’d probably be best served by something pressurized. A turbo certainly makes sense though if you routinely fly in the Rockies.
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I’m looking at a twin comanche, comparing the NA vs turbo PA30s.

For example on my previous xc trip, I was flying from Chicago to NYC in the Arrow. She flies about 130kts. Weather was crappy en route up to 8-10k so I was able to fly above the weather at 11.5k. Maybe this was an isolated circumstance, I don’t usually aim to fly high, just depends on the factors.

At higher altitudes the tailwinds were even higher. Winter days.
 
Lance F said:
Then fly lower. That’s the advantage of the turbo. Pilot can fly low or high.
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That’s what I did on the way back, low altitudes were winds calm. Was getting 130-135kts GS on the way home at I believe 4.5k.

On the way there at 11.5k was getting 180kts GS.

I would say Chicago to NYC is 5 hours there and 6 hours back. It’s a long day for me. If we saved an hour, might do it more often and might be more bearable. Not looking at a turbo for altitude per se but more so for the increased speeds. I’m guessing 20% faster?
 
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mandm said:
I’m looking at a twin comanche, comparing the NA vs turbo PA30s.

For example on my previous xc trip, I was flying from Chicago to NYC in the Arrow. She flies about 130kts. Weather was crappy en route up to 8-10k so I was able to fly above the weather at 11.5k. Maybe this was an isolated circumstance, I don’t usually aim to fly high, just depends on the factors.

At higher altitudes the tailwinds were even higher. Winter days.
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I’d wager an early 310 or 55 Baron would out perform a turbo PA30 for about the same operating cost.
 
3000 or so hours with turbos. From a reliability standpoint never really had an issue.

The dislike from a maintenance perspective is the limited space under the cowl to stuff a turbo system compared to the NA equivalent. So access is tight and may find removing parts of the turbo system to get at other things.

In my experience Mooneys are really tight, Bonanzas a tiny bit less so, and Cessna and Piper singles a little better for access. Cessna twin turbos are easiest as the nacelles are big.

From the front range west a turbo is really really useful. East of there it’s still a nice to have.

Make friends with mouse milk if you get a turbo.
 
Grum.Man said:
I’d wager an early 310 or 55 Baron would out perform a turbo PA30 for about the same operating cost.
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I looked at 310s on TAP and they look well uncared for and not updated. Just my initial thoughts. Haven’t looked at the 55 Baron yet.

Should I consider a Cirrus?
SR22 185kts
SR22-G2 is saying 169kts? Did it get slower?
SR22T 213kts
 
mandm said:
I looked at 310s on TAP and they look well uncared for and not updated. Just my initial thoughts. Haven’t looked at the 55 Baron yet.

Should I consider a Cirrus?
SR22 185kts
SR22-G2 is saying 169kts? Did it get slower?
SR22T 213kts
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It’s hard to find a good 310 for sale because a good 310 is hard to let go of. The same is probably true of Barons. You have to be patient and a little lucky but, if it works out, you can be the next guy who doesn’t ever want to sell the plane.

I think everyone should consider a Cirrus. They do their thing very well and make a good reference point to decide how well another plane would fit your mission.
 
mandm said:
That’s what I did on the way back, low altitudes were winds calm. Was getting 130-135kts GS on the way home at I believe 4.5k.

On the way there at 11.5k was getting 180kts GS.

I would say Chicago to NYC is 5 hours there and 6 hours back. It’s a long day for me. If we saved an hour, might do it more often and might be more bearable. Not looking at a turbo for altitude per se but more so for the increased speeds. I’m guessing 20% faster?
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This morning JFK to ORD would take me 5:11 and 4:09 coming back, no turbo and I get about 17 mpg. That would be at 10000’, but of course that would change with amount of wind.
Some people don’t like wearing oxygen masks or cannulas.
 
mandm said:
I looked at 310s on TAP and they look well uncared for and not updated. Just my initial thoughts. Haven’t looked at the 55 Baron yet.

Should I consider a Cirrus?
SR22 185kts
SR22-G2 is saying 169kts? Did it get slower?
SR22T 213kts
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A few 310s out there are in great shape. Most are not. The cheap ones out there will take buckets of money to fix, with a limited pool of qualified pilots that might buy the aircraft should you choose to change mounts. Turbos versions are available in the Q and the R models but they are a lot of airplane for many.

If a Cirus is in the budget, probably can't be beat. They seem to be very fast and efficient. Demo'd one once and at 12,500' was doing 188 KTAS on 17.5 gph LOP. Can be had with deice, which seems mandatory to make the most use of the turbo since you'll be climbing on top often and then descending through potential ice in winter.

The 213 KTAS number for the SR22T is undoubtedly at its max altitude somewhere in the FL200s. But and honest 180-195 KTAS seems quite plausible.
 
MooneyDriver78 said:
This morning JFK to ORD would take me 5:11 and 4:09 coming back, no turbo and I get about 17 mpg. That would be at 10000’, but of course that would change with amount of wind.
Some people don’t like wearing oxygen masks or cannulas.
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4:09 out, 3:22 back in a Bravo at 13,500 if I left both directions now. Run at 75% don’t really care about gas mileage, but estimate about 10.5 nmpg.
 
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So, ah, random question. When did the conversation about fuel consumption in the aviation world go from GPH to MPG?
Seen a couple of posts by different people making reference to this new (in the aviation world) unit of measure.
 
guest user said:
So, ah, random question. When did the conversation about fuel consumption in the aviation world go from GPH to MPG?
Seen a couple of posts by different people making reference to this new (in the aviation world) unit of measure.
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The POH for the last three aircraft I've owned, manufactured between 1960 and 2001 all had Nm/gallon in the performance tables. Usually 12-15 for a singles and 4-7 for the piston twin. POH is no wind value of course.
 
PaulS said:
4:09 out, 3:22 back in a Bravo at 13,500 if a left both directions now. Run at 75% don’t really care about gas mileage, but estimate about 10.5 nmpg.
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4:10 and 3:30 at 9,000 in the 310 using my numbers. 105 plus 88 gallons for a trip average of about 155,000 rods to the hogshead (6.7 nm/gal).
 
guest user said:
So, ah, random question. When did the conversation about fuel consumption in the aviation world go from GPH to MPG?
Seen a couple of posts by different people making reference to this new (in the aviation world) unit of measure.
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About the only time I mention MPG is if the wind is really howling. I was going from Dallas to Chicago at 8,500' one day and was seeing 23MPG. Of course if I was going the other way, it would have only been about 11MPG. But I was always burning 13GPH.
 
guest user said:
So, ah, random question. When did the conversation about fuel consumption in the aviation world go from GPH to MPG?
Seen a couple of posts by different people making reference to this new (in the aviation world) unit of measure.
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Because people fly trips as a distance, not time. And that indicates how efficient your airplane is.

Burning 18 GPH can be great at 200+ knots, but pretty bad at 130 knots.

But I really like my 17+ MPG (175 KTAS at 10.1 GPH).
 
I spent a couple thousand hours operating the Aztec and 310 before I moved to the 414. Flew Navajos (turbocharged) in there as well. Spent some time flying a RAM IV T310R (a real hot rod) and have had some others in there.

Basically, a turbocharged plane works its engine(s) harder. You've got more heat, which will tend to lead to lower service life, more issues. You've got more parts to fail in the turbo and the associated controllers. The exhaust is under more pressure (literally, since exhaust pressure feeds the turbo) and are something you need to be more concerned about. Not sure about support or parts on the Twin Comanche as I believe those turbos were all aftermarket, so that might be a consideration. Most of the time turbocharged engines have a more complicated fuel system since the fuel nozzles are pressure balanced and you have more expensive fuel pumps.

After spending a couple thousand hours flying the Aztec and 310 around the country without turbos, I was pretty used to flying in the lower altitudes, in the soup, etc. that you get. In a non-pressurized turbo aircraft you're wearing cannulas or a mask at the altitudes where the turbos really do you any good, neither of which are particularly comfortable and the novelty wears off. Lycoming engines I find generally hold up better to turbochargers than Continentals, but that's not to say they're trouble-free. You will sometimes get some really great tailwinds up high that are worthy of Facebook/Instagram posts, but the reality is that most of the time you'll notice the headwinds more. Yes, you can get above a lot of the weather a lot of the time and get some smoother air, but even my wife up at FL450 in her Challenger has to deviate around storms.

Personally, I'm not interested in owning a turbocharged plane again and generally advise people against buying them. More maintenance headaches, and generally fewer benefits than you'd imagine. The exception to that is if I flew over the Rockies regularly where the extra altitude is beneficial to avoid cumulogranite. However, I've crossed the country coast to coast (including over some tall rocky sections) with the 310 and the Aztec, naturally aspirated, just fine. You just have to do a bit more careful planning which, frankly, you probably should be doing anyway in a piston aircraft.

The one exception would be if I got offered that RAM IV T310R at the right price. That, I would buy. But that plane is just awesome.
 
Ted said:
Personally, I'm not interested in owning a turbocharged plane again and generally advise people against buying them. More maintenance headaches, and generally fewer benefits than you'd imagine. The exception to that is if I flew over the Rockies regularly where the extra altitude is beneficial to avoid cumulogranite.

The one exception would be if I got offered that RAM IV T310R at the right price. That, I would buy. But that plane is just awesome.
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Have felt the peace of being at FL190 over the Rockies at 2am in a Turbo 310. Not the same in an NA airplane - you will descend below 14,500' on one engine. Out west I really like turbos and generally had few issues with them or the engines. Probably a little more expensive overall, but for that mission, worth it. But 310s are long in the tooth and many have already foundered.
 
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