First time to fly a turbo . . . tips and tricks

[weloveseaplanes]

Gidday Gidday all,

Will soon be flying a 2005 turbo T206H with a TIO-540. Oxygen equipped. Have never flown a turbo before or used oxygen.

Can anyone with experience on T206Hs/turbos/oxygen in general offer any tips and tricks on :

a) not breaking anything
b) using them efficiently?

Cheers

[Aeromuz]

1. Before you release the brakeson your take off roll ensure you are getting boost ie. More than 30' MAP, if not then abort the take off.

2. On descent (for the circuit) reduce MAP by 1' per minute to gently cool the turbo (no shock cooling, they dont handle that well). Back to about 20' - 22' MAP usually for the circuit depending on weight. This requires a bit of forward planning in flight so think ahead of the aircraft.

3. Upon landing ensure a minimum of 3 minutes (5 preferably) to futher cool the turbo.

Beyond that its business as usual, all the same engine management points that you would normally use still apply.

I hope this helps mate, good luck.

Muz

[beat ups are fun]

The decent planning is the most important thing. you need to understand the amount of heat that the turbo is producing to realize why it's so important. on C402 at night you can often see the turbo glowing orange. hence take extra caution on decent.

don't forget to always park into wind after landing to take advantage of the extra airflow through the cowl.

On long taxis keep an eye on your temps, if you have to hold for a long period, turn into wind on the taxiway.

High oil temps cause the waste gate to not operate properly on some engines, usually you will notice full throttle being 1-2 inches off where it should be.

Lastly have a chat to your LAME about your particular engine and understand how the turbo system works. It could make a big difference one day when the donk starts making silly noises.

As for efficiency, you only get the extra value out of a turbo aircraft at higher altitude. try to cruise at 8000+ where you can.

[Mr. Hat]

In my time the turbos I flew tended to be a bit sluggish in the circuit particularly on a hot heavy day. What I learned after some time on type was to manage the descent to arrive in the circuit higher than normal so as to avoid disrupting the 12 inch/minute cooling process. It was a satisfying engine to manage and made you more aware overall.

It could be a handful to start when already hot on a hot day. Needed a lot of priming (throttles open mixtures off pumps on). Anyway that was our procedure see what your company wants for yours.

[CirrusSR22T]

Hey Seaplanes, if your using a nasal cannula, ensure that your oxy lines don't get crimped by you or your pax accidently sitting or resting on them ! :ouch:

Also get yourself a Oxymeter, you stick it on the end of your finger every 10-15 mins and it will give you your percentage oxy sat levels and resting heart rate. if your % oxy levels get low, a quick big inhale should get them back up to over 90%. (you can get the oxymeters for around $100 USD on line).

lastly, enjoy the great view up in the flight levels :ok:

[TSIO540]

On cold mornings it can take quite a while to get warm oil into the waste-gate mechanism so sometimes that can make it a bit sluggish to close and therefore slow to bring on the boost. Expect some lag, pause on increasing the throttle position once you get just over 30" to allow the turbo to spool up then feed in the remainder smoothly.

If you're sticking to 500fpm RoD, then 6nm/1000ft may work out well for descent planning; especially if you have to advise ATC as they will typically only allow for 3nm/1000ft.

For any given fixed manifold pressure, boost will be higher as you climb, lower as you descend... so that 25" at 10,000ft boost should be around 6"; at 1000ft 25" should be producing no boost at all (therefore a coolish turbo).

Sea level manifold pressure is around 30" less 1.5" for engine inefficiencies (e.g. air filter, throttle turbulence) so its typically around 28.5".

Then, you will need about 1" of boost per 1000ft on climb to maintain the same manifold pressure.

Be mindful that traffic in the flight levels will typically be TAS'ing around 240kts+

Watch out for the EGT, keep it within limits, especially on descent.

Don't slam the mixture full rich at ToD, or shock cooling can result.

If you're on the Oxy be mindful that it is at zero (or close to it) humidity, so STAY HYDRATED! Hypoxia is induced earlier when dehydrated. Get familiar with the symptoms of hypoxia and don't muck around with it. If more than one pilot/pax is using oxy, make sure you use an antiseptic wipe on the nasal cannular tubes so that you don't catch anyone else's cold.

Descending from flight levels with a cold might leave you with barotrauma so don't try it.

Have a look through the performance section of the manual and run a few basic calculations to compare time, fuel & distance to climb vs TAS and Groundspeed so that you end up at select the most efficient level you can.. i.e. not at FL220 for a 30nm sector and not at 3000 for a 120nm sector.

Good luck, enjoy it!

TSIO540

[Plow King]

And read articles 31-36 here (http://www.avweb.com/news/pelican/182146-1.html) (and all the other engine management ones for that matter, it's all good!)

PK

[Peter Fanelli]

1. Before you release the brakeson your take off roll ensure you are getting boost ie. More than 30' MAP, if not then abort the take off.


Clearly you've never operated off anything other than a nice wide black sealed runway.

[Aeromuz]

Yes Peter I have, however he was asking for tips on operating a turbo charged engine not operating on a gravel strip. Im sure hes a big boy and can make up his own mind as to when he should follow that advice or not.

Rather than trying to criticize, how about you contribute something positive to the discussion, as the other have.

[Xcel]

I'm not familiar with the t206h if it is fixed or automatic wastegate...

Main thing is be smooth... If it's automatic then easy as - smooth on applying power - remembering as it makes boost after passing the n/a map limits it increases at a faster rate. Check map at full throttle during roll.

If fixed you can't apply full throttle and must set your required map without overboosting - just take some t/o's to get a feel for it and scan agin being mindful of the overboost light and map.

On decent you need to plan your power reductions remembering it may not coincide with your todpt. Inch a minute is a good rule of thumb... I used an inch every 2 minutes on some gear just depended on the Cp and sop's.

For the oxy as others have said - know the limits of the gear - chances are you'll spend moat of your time with it off but if it's on probably only upto 14000" unless your punters have oxy as well. Understand your limits as well as the system hypoxia can creep up on even the most seasoned guys. Always check the bottle ... Keep a stopwatch or a time for using it if you want. Include lines and flow bars as part of your scan. Hard to not have an escape route in Oz as we got no terrain but just be mindful - if in doubt descend no problems there.

Have fun you will enjoy it - no more advancing throttles in climb...

Cheers
r

[an3_bolt]

Might find some additional information from the Lycoming Flyer:
http://www.lycoming.textron.com/support/tips-advice/key-reprints/pdfs/Key%20Operations.pdf

[Capt Fathom]

I thought he wanted tips for a T206? You guys are making it sound like the Space Shuttle!:E

[Joker 10]

Peter F you are right on the money, no prop damage means bring up boost on the run, the turbo will come into play at about 30 knots indicated then go for full power ( max boost for density ) props actually cost more than Turbo's.

[AerobaticArcher]

Bringing the boost up slowly on the run is a good idea, if the dirt runway is 2k long. Most POHs state takeoff distances calculated are from full power application, so, why not ride the brakes until full power is applied. If you keep the aircraft moving at a speed greater than walking pace, you won't damage the propellers.

[Peter Fanelli]

I thought he wanted tips for a T206? You guys are making it sound like the Space Shuttle!
:ok:

The message you have entered is too short.

yeah yeah.

[18-Wheeler]

2. On descent (for the circuit) reduce MAP by 1' per minute to gently cool the turbo

I've heard this a lot and am not convinced about it at all.
True enough I'm more familiar with car turbos and not aviation ones but the car ones are very robust and can take huge temperature changes without any trouble at all, even the older oil-cooled (and lubricated of course) bearing types.
I suspect the real cooling with turbo piston aviation engines is more the manifolding (with regard to expansion & contraction from the heat & temperature changes) and the engine itself with the usual rapid temperature changes.
I'm quite prepared to be wrong - any ground engineers have any good information on this. And apologies for the thread hijack.

[VH-XXX]

so, why not ride the brakes until full power is applied. If you keep the aircraft moving at a speed greater than walking pace, you won't damage the propellers.

You would never get to fly an aircraft that I own with operating procedures like that!!! or any operator that I know for that matter!!!

[Chimbu chuckles]

Reading Deakin's articles is excellent advice from a general knowledge point of view but unless this particular engine also has Gamijectors/engine monitor some of the specific techniques won't be available to you. Having said that who, in their right mind, wouldn't have them fitted to a latish model T206?

If this aircraft is so fitted operate it exactly as John suggests as long as that is in accordance with the owner's wishes (I suppose). If not then reducing MP an inch/minute on descent won't hurt a thing but be aware than once you're down around 5000'/20 in MP then the turbo is not doing much and hasn't been for a little while. Its cooling nicely and you can leave it at 20 in until joining downwind and then bring it straight back to whatever setting is appropriate for speed reduction to Vfe and then leave it there - merely adding drag (flaps) as you curve around base and final - one last reduction to idle as you round out. I haven't flown a T206 since 1987 but if memory serves 12-15in MP on downwind.

Since the Turbo has been cooling and spinning down for the last part of the descent, the circuit and approach/landing, the coolest it will be is on touchdown. Every minute you spend sitting at idle on the ramp is just heating it back up again - and your pax.

[flywatcher]

Capt Fathom
I know a lady quite well who has flown the space shuttle three times, in fact she is visiting in a couple of weeks, and she would tend to disagree with you, having been one of the very few people to fly both.

[Old Akro]

The Deakins articles are quite good. But the oracle is the engine operators manual. Hardly anyone uses them anymore, but the two I bought for engines I fly are excellent. At the end of the day, the guys that wrote them (on manual typewriters) almost certainly have more engine dyne time than anyone else. The 2 engines for which I have manuals have a lot less discrepancy between the Deakins / GAMI leaning procedure than Deakins would have you believe.

[RadioSaigon]

Since the Turbo has been cooling and spinning down for the last part of the descent, the circuit and approach/landing, the coolest it will be is on touchdown. Every minute you spend sitting at idle on the ramp is just heating it back up again - and your pax...

Exactly. Worth the repetition for clarity. This OWT of sitting there "idling a turbo down" is the worst kind of nonsense -as anyone that has flown a C402 can attest, after watching the glow in the cowls from TOD. It is pointless and potentially damaging to go stacking heat back into an already cool engine.

[Mr. Hat]

Sounds logical but the owner of the aircraft wanted the three minute cool down. Would be interesting what to hear what Engineers think of it. Mettalurgists even better.

[RadioSaigon]

Fair enough.

Perhaps another slightly relevant example... I have a twin-turbocharged car. She's quick, and I work her. When I get home, I simply turn her off, as would anyone with a normally aspirated car; no run-down, no idling, no bull****. I know when I hit the town limits that she's off the turbo's -all they're doing for the final drive home is spinning down and cooling. Perfect.

Now, a few years ago a young neighbour had a Godzilla, that from the time the engine fired in the morning was valve-bouncing up the road at the red-line. When he got home, it'd sit outside idling for anywhere between 15-30 minutes most nights.

One day he came to me when I was washing mine to enquire how many turbo's I'd gone through. Of course she was (and still is) on the originals. He'd gone through 3 in 6 months. I asked him if the difference in our engine-management strategies might provide the answer... :}

I'm pretty anal about running her up, 1st start of the day and of course allow a minimal run-down if stopping from a quick run. Other than that, I pretty much treat her like any other car. She's still as quick as ever she was and will show a clean pair of heels to damn near anything else on the road. I've owned her for 14 years now, turbo's are still the originals with no signs of damage or distress, my engineer tells me.

Can't be all bad, I reckon.

[ForkTailedDrKiller]

She's still as quick as ever she was and will show a clean pair of heels to damn near anything else on the road.

Except a big bore V8 that eats hair dryers for breakfast! :E

Dr :8

[Chadzat]

RadioSaigon- I would hazard a guess that you have water-cooled but oil lubricated turbo's. Most automotive turbo's since the early 1990's are cooled by coolant from the engine cooling system. You may already know this, but the coolant inlet and outlet fittings are installed to the turbo to allow convection cooling. Basically even with the engine turned off (and hence no water pump to flow coolant through the system) the warming of the coolant in the core of the turbo will keep enough coolant flowing to cool the bearings and avoid turbo damage. Older cars with older tech turbo's used to need turbo-timers to be installed so that you could park and get out of your car while the engine was still running to circulate oil through the turbocharger to cool it. Funnily enough the "fully sick" brigade that have these installed in newer cars dont actually need them.

Aircraft turbo's obviously have no coolant and are oil lubricated and cooled. As a few posters have already said, the coldest a turbocharger (note- NOT the engine) will ever be is on touchdown. The previous few minutes of descent before landing requires minimal engine power and hence the wastegate is normally fully open, meaning the turbo has already had its 'run-down' time. If you sit on the ground for 3-5 mins you are more than likely going to heating up your engine oil, and hence the turbocharger core. Its probably not going to damage it any further, but its really not required! :ok:

[RadioSaigon]

Except a big bore V8 that eats hair dryers for breakfast!

ROFPML Wondered how long it would take! Nah, Ford & Holden are yet to produce anything that can touch me -in the straights or especially the corners :E

I would hazard a guess...

Sorry bro, guess again ;) She wasn't new when I bought her and she recently qualifies as a "veteran"! My point was that a properly cared-for turbo neither requires nor benefits from turbo-timers or extended run-downs. WRT your comments re aircraft turbo's, I know -I've spent a little time driving them- and concur! Really I think your comments just illustrate the point I was making, although I was probably less eloquent!

[sms777]

I miss my supercharged Queenair.....:{. No lag, no cooldown, boost driven by crankshaft not by fart....:E

[ForkTailedDrKiller]

OK RS, time to show your cards, what manner of hair dryer are we talking about here and what is your 0-100 km time?

Dr :8

[Joker 10]

Audi A8 4.2 litre twin turbo oil burner saloon Quattro 5.6 seconds 0 to 100, torque makes it quick

[RadioSaigon]

OK RS, time to show your cards, what manner of hair dryer are we talking about here and what is your 0-100 km time?

OK, she's a 1990 Mitsubishi GTO, at standard spec developing 320HP at the wheels -all 4 of them. hmmm... the 0-100 time. To be honest, I've never dragged her. I like the whole drive-train in it's current state too much for that -it cost me a bloody fortune to get it right!!! Additionally, I've removed the catalytic converters which does significantly increase the turbo lag due lower back-pressure, so outright acceleration times are definitely below standard spec IMO -but at the other end, she does breathe more freely once they're spun-up & on song.

No, when I say Ford & Holden are yet to build anything that can touch me, I'm referring solely to real-world experience on-road. It's a pretty endless experience too BTW... every HSV, XRwhatever and other performance car on the road wants to have a go at you. Sometimes I play, often not. I just let them go... until I catch them in a corner a few minutes down the road, when all I do is pass them so I can watch another one dwindle in the mirror.... I'm usually in the pub with a jug & a pie consumed by the time they get to the end of the run :E

There's a cop that thought his XR8 was pretty quick, tried to show me over a mountain road one day. I passed him, he tried to keep up, but not for long. His mate pulled me up (at a very sedate 95kmh) right where I expected him to. I chatted the whole thing through with their boss about an hour and 130km further down the road at a meeting we both attended, just as I promised the one who pulled me up I would ;) We decided that XR8's really ain't that quick, really can't handle and the cop driving it was a (Richard Cranium).

I could give you his telephone number if you like ;)

[ForkTailedDrKiller]

OK, she's a 1990 Mitsubishi GTOHa, ha - RS, by the book figures I have we would be side-by-side going through 100 km/hr, and the Audi A8 would still be kidding himself that it could go a bit.

Dr :8

PS: .....and I would have nothing more to prove before we got to a corner!

[RadioSaigon]

She's a great car for a 1990... can't help but wonder what a new technology new-build would go like -if they were ever game to build one!

We'll have to get together for a pie & a jug at minimum sometime :ok:

[sms777]

This is becoming a serious thread drift but let me join in before it gets locked.
GTO is an iconic brand made famous by Ferrari back in the late '50's and early '60's then stolen by Pontiac of GM USA when they rebadged their Le Mans intermadiate sedans by fitting big block 389 ci engines thus creating the first factory built "hot rods" instantly creating a horsepower histeria right across the US. From there on engines grew in size and made their way into even smaller cars creating super cars like the Shelby Cobra's.
Japan has always been a leader in the world in copying super cars decided to steal this iconic badge and put it on the previously very seriously boring Mitsubishi buzz bucket but knowing that it will be a laugh with it's milk bottle size 2 liter engine so bolted a massive hair drier on to it to compensate and show some figures. It made impressive times alright.....
Which GTO would you own?

I do own one of them...and it is not the Jap one. ;)

[RadioSaigon]

hmmm... as far as I'm aware, the GTO marque doesn't owe loyalty to any particular brand, serving rather as an abbreviation for Gran Tourismo which is a spec the Mitsubishi GTO certainly fits.

The "milk bottle size 2 liter (sic) engine" to which you refer is, in fact a 3 Litre V6 -and a very appropriate fit, and a very capable and robust engine. I'm perfectly happy with the GTO I currently have, thank you. I certainly wouldn't thank you for a Yank Tank of any description. They still can't build a decent touring car. The Ferrari I may one day aspire to.

So what GTO do you have???

[sms777]

There is no royalty, the reason why Pontiac managed to steal the badge. it stands for Gran Tourismo Omologato.
Guess what... i own the Yank Tank version. A 1967 Royal Bobcat with a dealer optioned 421 engine which I have have restored and slightly modified to the extent to give you enough fright for you to give up worshipping Jap Crap and buy real muscle.
Remember... there is no substitute for cubic inches.

[18-Wheeler]

Remember... there is no substitute for cubic inches.

There's a number of substitutes for the knuckle-dragging scene.
There's technology for one and another is simplistic elegance.
My fastest road car doesn't have a turbo, nor does it need one.
Two litres of Toyota that makes a good 220hp is enough.

http://www.billzilla.org/fraserprog9.jpg

I've never done a drag race in it either (I'm a circuit racer) but it should do the 1/4 mile in 11-something.

But back to the topic - What is the problem with fast cooling in a turbo piston aviation engine? I doubt the turbo unit itself is going to suffer from too-rapid cooling, so what is it? The barrels in the engine suffering from excessive temperature differential ... ?

[ForkTailedDrKiller]

I've never done a drag race in it either (I'm a circuit racer) but it should do the 1/4 mile in 11-something.

Now that car is a perfect illustration of how ugly women get laid! There is always someone with no taste willing to do the job. :E

Dr :8

[RadioSaigon]

Remember... there is no substitute for cubic inches...

On that we're going to have to agree to differ, I'm afraid.

Brute horsepower has it's place, no argument... but I believe the spirit of the GTO tradition lies in grace, agility and the ability to maintain speed in whatever the road brings you. I reiterate, the Yanks have dismally failed to ever build a car capable of handling a corner -or IMO embodying any of those underlying qualities, and quite frankly I find them unappealing... ugly even. They just don't do it for me, I'm afraid. I'll take ability and finesse against brute horsepower every time.

To the OP: my apologies for the severe thread-drift! I can only hope the discussion surrounding turbo's has been of some benefit!

[MakeItHappenCaptain]

Biggest tip for flying the T206H

Read the Pilot's Operating Handbook. You won't be asked to fly it sight unseen.

Not trying to be a smartarse, but you should find everything you need to know in there before having to resort to asking a chat forum, then if the owner/operator (who will want the aircraft flown their way) or an engineer can't answer any specific issues, ask away.:ok:

[Stationair8]

Wise words from MakeItHappenCaptain.

Also worth reading is Aircraft Engine Operating Guide by Kas Thomas.

So many variables in a turbo engine, a density controller not setup correctly, fuel controller not set correctly, EGT gauge not calibrated, EGT probe past it's best, leaks in the exhaust system, engine baffles, CHT probe, etc.


Now girls having a turbo on your four cylinder pox box may light your fire, and may get get your girlfriend's panties wet, but nothing beats the Australian legendary 1971 Ford XY GT HO Phase 3 for pure muscle car performance.

[ForkTailedDrKiller]

Ford Falcon XY GTHO Phase III = 0-60mph (0-100 km/h) in 6.4 secs !

That's about 1 sec slower than the current model Holden Commodore SS! :E

On the other hand, my 1979 V35B is as fast as the 2011 G36!

Not sure what that all means - but it is interesting none-the-less!

Dr :8

[Biggles78]

All this interesting info for the OP, I am going o have to dig out my old Kane Mk6b to work out the drift and get back on track. :eek:

[UBE]

The trouble with shutting down a turbo that has been working hard (or Hot maybe better) quick, apart from the rapid drop in the metal temps is that the oil will boil and be reduced to a carbon type crap in the bearings, reducing bearing and thus Turbo life. If you have a digital turbo and EGT temp gauge you can actualy see that the temps of the gases going through the turo do drop further at idle after the power required to taxi. We require below 600f or 3 min. Talk to an aircraft enginer.

[18-Wheeler]

but nothing beats the Australian legendary 1971 Ford XY GT HO Phase 3 for pure muscle car performance.

PMSL! That wasn't even true 40 years ago.
I've got a two litre Toyota that's nearly as fast and it doesn't have a turbo. My Fraser, pictured earlier, is so much faster it's not funny.



The trouble with shutting down a turbo that has been working hard (or Hot maybe better) quick, apart from the rapid drop in the metal temps is that the oil will boil and be reduced to a carbon type crap in the bearings, reducing bearing and thus Turbo life. If you have a digital turbo and EGT temp gauge you can actualy see that the temps of the gases going through the turo do drop further at idle after the power required to taxi. We require below 600f or 3 min. Talk to an aircraft enginer.

Good point - I was going to mention earlier that the oil is still cooling for quite some time even after the CHT's had stabilised.

[toolowtoofast]

the other 'problem' with the O520 is that it can be a little fragile, and does not respond to shock cooling, or more accurately, uneven cooling (front cylinders getting colder than the back ones) very nicely - cylinders develop cracks from the spark plug to the valve seat, reducing compression and degrading performance. your boss will not appreciate having to replace/repair multiple cylinders at every 100hr inspection.

There is a reason that the turbo O520 has a 1200hr TBO.