First off, I appreciate everyone that chimes in and shares their knowledge.

I was hesitant about starting another thread so soon after my last but couldn't find much on this topic on BCP or even online. I've been trying to do some due-diligence on an STC that is a turbo system for the IO520... (Just kicking it around).... I really like the tornado alley, but it's $$$$ -- Looking into another STC that is a little more cost-effective, however it has the technology that is a wee-bit dated. It calls for a manual turbo waste-gate.

My question is, how is this on the Pro's and Con's scale? (Hazards, Procedure, Safety ...etc)

Thanks again everyone! I enjoy tossing around these ideas and gathering as much info as possible to make informed decisions.

First, why do you feel you NEED a turbo system on this airplane? It would have to be a REALLY compelling reason for me to even consider.....and even then, I'd probably not do it.

Turbos are way more hassles and maintenance and fire risk than they're worth in an airplane like the 185 in my opinion. And, cobbling a system up raises all those risks considerably.

I've known one 185 turbo conversion that I thought was well done.....massively expensive, heavy and did I say massively expensive?

Sell that 185 and buy a turbo 206, IF you REALLY need a turbo.

MTV

Agreed

I used to fly a Twin Commander that used manual waste gates.

Keep your attention on how much allowable manifold pressure is being generated. Do not over boost, for example in a descent start bleeding off turbo pressure early if manifold pressure is an issue. The STC should have guidance.

Basically there are two throttles. One for atmospheric pressure and one for the waste gate.

And of course any turbo is expensive to operate. TBO is less predictable. Unless you need it for DA, I would pass.

After being part owner of 2 turbo'd airplanes (TR182 and T210) and having regular access for a couple of years to a Mooney 231, I have to echo: if you don't NEED a turbo, do without.

So when do you NEED a turbo? Here are some examples:

If you're regularly flying in the upper mid-levels for some reason, i.e., oxygen needed, just below flight levels, and you want to be able to fly in the flight levels (18,000' on up) fairly regularly. But to justify flying that high, you have to be flying long legs, due to the time-to-climb issue. And you have to want to be on oxygen, something that is less onerous with a cannula (limited to 18,000' or lower) and clumsy with even a good mask (18,000' on up), but it's still annoying. But a normally aspirated 520 in a 180 or 185 can handle the lower mid-levels pretty easily, up to about 15,500', where anemia sets in and it runs out of breath.

If you're regularly climbing out of very high density altitude airstrips (like 10,000' DA) with a full load and need the sea level climb capability to clear all the terrain surrounding those airstrips.

But if your apparent "need" is only sporadic, it just isn't worth it. The cost is really prohibitive, the maintenance costs usually go up, and the life of the engine is usually shortened. Fuel use goes up dramatically, too, because who has more power and doesn't use it?

Even those "turbo-normalized" installations, which claim to only add enough boost to bring the engine back up to sea level power, add significant extra stress to the engine--even operating out of sea level airports, full sea level power of a normally aspirated engine is only used for a short time, on the take off roll. But a typical turbo-normalized engine is used at sea level power all the way to cruise altitude and typically at a pretty high power setting while cruising.

The result is higher CHTs, which equates to shorter engine life, and certainly the good possibility of cylinder problems along the way to TBO.

On the other hand, I do know many turbo owners who are satisfied, but their engines came that way from the factory, and they still have had extra maintenance issues.

Cary

I miss the turbo I had in the 210, and have mixed feelings about whether I'd put one in the 185. I was pretty sure I'd do it when oil price were high, business was good, and I was kidding myself about the total cost.

Now, I don't have the money and I'm talking myself out of it. The TAT option is too expensive unless you're a glacier sight seeing operator on Denali that can make it pay. It's heavy. It's hard to work on and clutters a nice simple engine cowl. Is cooling going to be an issue? The cooling wasn't designed for a turbo. Honestly, I liked flying high in the turbo, and the climb rates heading to 16-17K were amazing, but low and slow on floats is fine too. I've been to 11,500 on floats, and it was a while getting there. Once there, the MP was a bit discouraging, but I'm just not in that much of a hurry anymore. The lakes I've been to have been 4K or lower.

I could get fairly excited about installing a TSIO-550 F like Vitatoe is putting in the P210s, but until something like that comes along, I think I'll hold.

A manual waste gate? Yeah, I'd overboost it inadvertently for sure.

I don't have much to offer regarding manual waste gates, other than they seem like a very good way to make an already expensive and maintenance-intensive mechanism even more so, if mishandled.

I only have a couple dozen hours in a turbo...a 182 RG, and I didn't drive it in the flight levels. What I remember most of all about that airplane is that you could easily bust right through the $500 mark filling the tanks, and the performance wasn't even remotely close to justifying the fuel burn. If you really need turbo performance, seriously consider ditching the 185 and get something with retractable gear and a more streamlined profile.

It's nice to think that a turbo will give you sea level take-off performance at high DA's, but it really doesn't work that way. Ya...you get the horse power (which is GOOD), but the thin air still compromises your wing and propeller, so it's not the cure-all some think it is for backcountry operations. Reference the turbo 210 driver that killed himself and three passengers taking off from Upper Loon a couple years ago.

And FWIW, I worked with a guy who was a welder at a nationally known aviation exhaust company, and his opinion of aftermarket turbo systems was slightly worse than his opinion of gonorrhea, hemorrhoids, and taxes...combined. What amazed him the most was that enough people survived flying behind them to send them in for repair.

At this point, Im just kicking around the ideas on how to maximize the safety / performance on flying in and out of a ranch in MT that can see those high DA's. I'd like to stack the deck in my favor for those summer days and heavy load fall hunts. I've been in those situations where you'd pay a million dollars for ___X___ at that moment just to save your ass. The boost in cruise performance if just an added benefit and I'm not too worried about burning some dead dinosaurs.

I think I'll just stick with the normally aspirated and just tell the wife we're leaving early, under gross and to move the dinner reservations back an hour.

Thanks for your input everyone!

When it comes to turbocharging, my experience comes from the auto world. I have built a lot of turbo setups for gas and diesel stuff. What exactly are we talking about when we say "manual wastegate" ? To me this could mean a couple different things....

Turbocharging definitely adds an extra layer of complexity/weight and possible maintenance and hassle. But where I live (ground 6600ft) it can be extremely helpful.

I'd just like to know what is mean't by manual. In the car world, that would mostly likely mean, the wastegate is set to a base boost pressure, and can be controlled by either a manual valve or electric valve that would hold the wastegate shut until a higher boost output is achieved by interrupting the boost source driving the wastegate open along with the higher drive pressure in the exhaust before the turbo which is also trying to open the wastegate. In the case of altitude change this would allow the turbo to maintain the same overall manifold pressure at higher altitudes (up to the point where the turbo runs out of steam/is producing too much hot air and out of it's efficiency range etc.)The rotax 914 automatically adjusts this to maintain manifold pressure and output up to ~10,000ft from what I understand and therefore wouldn't be considered 'manual'

Anyway, if this is the case.. this of course would require the pilot to pay close attention to manifold pressure and make adjustments depending on altitude/conditions etc. Not out of the question of course.. and probably the way I personally would prefer it.. but more workload for sure....

Goose wrote:
I think I'll just ... just tell the wife we're leaving early, under gross ...

Even if you have a Twin Otter, that's the only way I know of to stay alive while flying in the mountains.

Goose wrote:At this point, Im just kicking around the ideas on how to maximize the safety / performance on flying in and out of a ranch in MT that can see those high DA's. I'd like to stack the deck in my favor for those summer days and heavy load fall hunts.

Get some mountain flying instruction in an underpowered airplane and turn that money into skill. That combined with a 300 hp machine and you're set.

GravityKnight wrote:When it comes to turbocharging, my experience comes from the auto world. I have built a lot of turbo setups for gas and diesel stuff. What exactly are we talking about when we say "manual wastegate" ? To me this could mean a couple different things....

Turbocharging definitely adds an extra layer of complexity/weight and possible maintenance and hassle. But where I live (ground 6600ft) it can be extremely helpful.

I'd just like to know what is mean't by manual. In the car world, that would mostly likely mean, the wastegate is set to a base boost pressure, and can be controlled by either a manual valve or electric valve that would hold the wastegate shut until a higher boost output is achieved by interrupting the boost source driving the wastegate open along with the higher drive pressure in the exhaust before the turbo which is also trying to open the wastegate. In the case of altitude change this would allow the turbo to maintain the same overall manifold pressure at higher altitudes (up to the point where the turbo runs out of steam/is producing too much hot air and out of it's efficiency range etc.)The rotax 914 automatically adjusts this to maintain manifold pressure and output up to ~10,000ft from what I understand and therefore wouldn't be considered 'manual'

Anyway, if this is the case.. this of course would require the pilot to pay close attention to manifold pressure and make adjustments depending on altitude/conditions etc. Not out of the question of course.. and probably the way I personally would prefer it.. but more workload for sure....

In all the airplane applications with a manual wastegate I've seen it is simply a vernier type pushpull control tied to the wastegate. Pilots "manually" set the manifold pressure using this control, there is no blow off valve.

It doesn't take much to get distracted and overboost the engine, that is the inherent danger of these setups.


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Halestorm wrote:

GravityKnight wrote:When it comes to turbocharging, my experience comes from the auto world. I have built a lot of turbo setups for gas and diesel stuff. What exactly are we talking about when we say "manual wastegate" ? To me this could mean a couple different things....

Turbocharging definitely adds an extra layer of complexity/weight and possible maintenance and hassle. But where I live (ground 6600ft) it can be extremely helpful.

I'd just like to know what is mean't by manual. In the car world, that would mostly likely mean, the wastegate is set to a base boost pressure, and can be controlled by either a manual valve or electric valve that would hold the wastegate shut until a higher boost output is achieved by interrupting the boost source driving the wastegate open along with the higher drive pressure in the exhaust before the turbo which is also trying to open the wastegate. In the case of altitude change this would allow the turbo to maintain the same overall manifold pressure at higher altitudes (up to the point where the turbo runs out of steam/is producing too much hot air and out of it's efficiency range etc.)The rotax 914 automatically adjusts this to maintain manifold pressure and output up to ~10,000ft from what I understand and therefore wouldn't be considered 'manual'

Anyway, if this is the case.. this of course would require the pilot to pay close attention to manifold pressure and make adjustments depending on altitude/conditions etc. Not out of the question of course.. and probably the way I personally would prefer it.. but more workload for sure....

In all the airplane applications with a manual wastegate I've seen it is simply a vernier type pushpull control tied to the wastegate. Pilots "manually" set the manifold pressure using this control, there is no blow off valve.

It doesn't take much to get distracted and overboost the engine, that is the inherent danger of these setups.


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yea there wouldn't be need for a BOV.... how does the push pull control interface with the wastegate exactly?

GravityKnight wrote:

Halestorm wrote:

GravityKnight wrote:When it comes to turbocharging, my experience comes from the auto world. I have built a lot of turbo setups for gas and diesel stuff. What exactly are we talking about when we say "manual wastegate" ? To me this could mean a couple different things....

Turbocharging definitely adds an extra layer of complexity/weight and possible maintenance and hassle. But where I live (ground 6600ft) it can be extremely helpful.

I'd just like to know what is mean't by manual. In the car world, that would mostly likely mean, the wastegate is set to a base boost pressure, and can be controlled by either a manual valve or electric valve that would hold the wastegate shut until a higher boost output is achieved by interrupting the boost source driving the wastegate open along with the higher drive pressure in the exhaust before the turbo which is also trying to open the wastegate. In the case of altitude change this would allow the turbo to maintain the same overall manifold pressure at higher altitudes (up to the point where the turbo runs out of steam/is producing too much hot air and out of it's efficiency range etc.)The rotax 914 automatically adjusts this to maintain manifold pressure and output up to ~10,000ft from what I understand and therefore wouldn't be considered 'manual'

Anyway, if this is the case.. this of course would require the pilot to pay close attention to manifold pressure and make adjustments depending on altitude/conditions etc. Not out of the question of course.. and probably the way I personally would prefer it.. but more workload for sure....

In all the airplane applications with a manual wastegate I've seen it is simply a vernier type pushpull control tied to the wastegate. Pilots "manually" set the manifold pressure using this control, there is no blow off valve.

It doesn't take much to get distracted and overboost the engine, that is the inherent danger of these setups.


Sent from my iPad using Tapatalk

yea there wouldn't be need for a BOV.... how does the push pull control interface with the wastegate exactly?

I dunno, never worked on one, never even had the cowling off one. In fact the only 2 airplanes I've encountered with such a system were one offs (I think).

I'm sure it was some of the best go-kart tech available in 1974...

I had a turbo normalized 185 on amphibs for a number of years . Really not that big of a deal to stay on it and not overboost it .You just need to pay attention . I thought it was great . Trying to get a floatplane off of an 8000ft high lake without a turbo isn't going to happen easily . After takeoff you can just dial it back so you are not using the turbo which is nice . That motor is still running right now past tbo from what I hear .

When you say turbo normalized, does that mean it was the Tornado Alley Turbo STC?

Anyone know who holds the manual wastegate STC?

Manual wastegates aren't a no go. They're just another thing to manage. Can they be forgotten in the descent and cause an overboost condition? Yes. Can the main landing gear be forgotten and configured wrong at touchdown? Yes. Can this risk be mitigated with good procedures, checklists, and pilot diligence? YES!

What are the details of the strip in MT that you'll be operating in and out of? With Sportsman, Wingex, 300 HP, and a modern propeller, you've already got a lot of performance stacked up.

Yup . Tornado alley . I thought it was a great setup . Turbo 185 on wheels is a kick ass machine .

I work on a commanche with twin Ray Jays on manual waste gates, mounted on an IO 540. Pilot does have to pay attention when decending for sure, but the thing sure like to climb.

On a manual waste gate controller, the vernier control in the cockpit manually controls the waste gate. So, at sea level DA, the waste gate would be fully open. Take off, and as you climb, the pilot gradually closes the waste gate, maintaining SL manifold pressure (or a boosted MP, depending on the system). Effectively, the pilot takes the place of the automatic waste gate controller.....and we all know about pilots.....

Goose, there are essentially two types of turbo charging systems in airplane's: Turbo Normalizing systems and true turbo chargers.

A Turbo Normalizing system only permits your engine to make sea level power at higher DA....NO boost above rated power. Those systems are RELATIVELY simple to install.

A true turbo system actually boosts rated HP. As such, many of the engine internals have to be changed....for example, supercharged engines typically use relatively low compression. Big $$$ in other words.

The manual waste gate is just more monkey motion in the cockpit, but start a descent from 14,000 DA some time to land at an 1200 ft DA airport, and neglect to constantly open that wastegate and you could make significantly higher pressures than your engine is designed for.

Use some common sense and I think you'll do just fine with normally aspirated engine for the mission you describe. And DAs out here USUALLY aren't that high during hunting seasons.

MTV

Pinecone wrote:
Anyone know who holds the manual wastegate STC?

http://metalinnovations.com/mii_repair/turbo-stc-185/

TAT is the holder for the STC with the automatic waste gate.

Well ya, turbos have some maintenance...but in 10 years if my 182Turbo normalized fixed gear, the 540 has run flawless...factory installed...and i wont put car gas in it....has been good everywhere...even short stuff..so lower loon off in 400'...if im lite....