PT6

[boofhead]

New to the PT6-28 (in a Kingair). Would appreciate advice.
How do I determine if the battery is ready for the second engine start? Do I use the generator when starting the second engine? How do I check the auto feather? Is there any problem setting the auto ignition to Auto for all flights (not just icing or high alt)? Do I pull the props to feather before or after shutting off the Condition levers? Is auto feather a no-go item? How hot would you let the engine ITT go on start? Can you modulate the ITT using the Condition lever?

[Ejector]

Hate to say it, but everything you asked is part of the initial ratting. Look up your manual.

:ok:

[Cardinal]

How do I determine if the battery is ready for the second engine start?
- Check the load on the operating generator. If below X% (50?) start the next one.

Do I use the generator when starting the second engine?
- I believe that is serial number specific on the 200, some can, some can't.

How do I check the auto feather?
- AF switch to Test, props in taxi, advance power on both engines until both side are armed, bring a power lever back, the prop will feather, then cycle in and out as torque fluctuates. Recover, and try the next one.

Is there any problem setting the auto ignition to Auto for all flights (not just icing or high alt)?
- Increased igniter wear during low power descents/taxiing, but no "problem" per se.

Do I pull the props to feather before or after shutting off the Condition levers?
- After. Easier on the hubs, blows less FOD around.

Is auto feather a no-go item?
- Yes.

How hot would you let the engine ITT go on start?
- Check the limitations. If that is out of the question (?!?) keep it in the green arc and you won't torch the engine.

Can you modulate the ITT using the Condition lever?
- Yes, but it is a rather advanced technique. A "get me out of this frozen hellhole" move of desperation when dealing with a weak battery or cold temps. Let N1 peak, advance the CL, when it nears limits go back to cutoff, and you'll be at a higher N1 than when you started. Repeat as necessary. I've used it, but I recommend one avoid this technique until very familiar with expected PT6 starting behavior. Screwup and it gets very expensive.

[toolowtoofast]

Scary to think that you need to ask these questions on here - they should all have been part of your T/R. I am staggered. I sincerely hope you are not single piloting.

[hoggsnortrupert]

I hope you are not who I think you are?:uhoh::uhoh::uhoh:
Former DHC-6 chappie: (F/o):ugh::ugh::ugh::ugh:
This is all very very basic T/R stuff:
Chr's
H/Snort.

[Cardinal]

The questions are a bit interesting, but not necessarily damning. He could be a required second-in-command, and at many operations the training for those guys is scanty at best. (Been there, done that.) Further, the B200 does not require a type rating in the U.S., and other locales. If he's multi-engine current he can legally grab the keys and go fly. Frightening, but legal.

[boofhead]

Cardinal is right. Scary, yes...
I am getting some time before going to the formal training, only flying with a line pilot due to insurance. Don't have access to good manuals or training materials and the other guy is not clear on the questions above. In particular, the auto feather check has been explained to me three different ways, and did not seem to be effective. This makes sense though, thanks a lot.
Of course I have the limitations on the airplane; my question, if I was not clear enough, is what limits do the operators use. The ITT limit for start is 1090 for example, but I would use 1000 myself. I am Dart trained, and "milked" the HP cock to keep temps under the limit when the battery was weak, but it was a lot easier to do than with a gated Condition Lever, hence my question. The shut down is shown with the props in feather both before and after the condition levers are pulled back, depending on the source of the document (the POH shows before) and I would like to know the reasoning. The procedure for checking the battery involves turning the master switch off momentarily and checking the subsequent charge rates, a procedure that seems unnecessarily complex. There must be a simpler way? So if anyone who has experience on the airplane can give me practical advice, especially stuff that will help me get through the sim check, I would appreciate it. Keep the criticism coming though, I enjoy it. In the US I enjoy being able to just hop in a new airplane and fly it. The first time I see some airplanes is when I am training someone else, and even if I say so myself, I am pretty good at it. 14,000 hours jet and 7,000 hours turbine must count for something...

[Agaricus bisporus]

I enjoy being able to just hop in a new airplane and fly it. The first time I see some airplanes is when I am training someone else, and even if I say so myself, I am pretty good at it. 14,000 hours jet and 7,000 hours turbine must count for something...


That is truly terrifying, on several different levels, from personal, professional (with a small "p") to legal and cultural.


Heaven spare us all!

Or...is this a PPRuNe windup? Tell me it is...puhleese!

[boofhead]

I started in Aus, have a UK ATPL (and others), have flown most places and on various airplanes from homebuilts to B744, and maybe just maybe I might know a bit more than you do about what is safe. The Kingair is a nice, pleasant airplane with few if any vices. It uses conventional procedures and numbers; where is the terror? Have I missed something?
My first questions were what I would have asked the group or the instructor if I had had the opportunity to do a TR, but it is not required nor available so I asked here. I am surprised at some of the replies given; I had forgotten how repressed aviation is in some parts of the world.
Cardinal; thanks for the answers, much appreciated.

[Ejector]

SImple, Tell the operator to buy a new readible manual.

[boofhead]

To all practical purposes, I am the operator. I have the POH and some training materials but each airplane is different. For example some have generator restrictions and each has a different model of engine.
I am pretty sure I have enough information now, and can face the guys at the simulator with confidence. If only the boss will pony up the money for the airfare...
Again, thanks. 8 replies and two of them from Cardinal actually had useful information. Not bad I suppose. I promise to report back about the training even if it is not successful..

[Dream Land]

If I remember right the -28 can get a bit warm when selecting feather at low idle, say for reducing your taxi speed, be aware of temperature limitation, the KA90 is real easy machine to operate.

[boofhead]

So far it has not been hot enough outside to have any temp problem. On start I usually see 500 ITT and at idle less than 400. Only above 16,000 do I see the ITT approaching the limit, although I only use 1200 Torque for climb. Does anyone start the engine in feather? Would it give higher temps? Very versatile engine.
On the airplane, if you would be so kind to answer another question:
At 16,000, oat of -22C, in cloud and picking up a little airframe ice (mainly on the spinners), the windscreens suddenly iced up, the heated section as well as the top and bottom areas where the heater coils are not present. I guess I could have used the wipers to help clear it, but did not try. When we left the cloud the ice fell off. I fly to places where the ground temps are down to -25C, and wonder if I would be able to clear the screens under IMC on approach? Bit hard to see out front otherwise.
The load meter showed that the windscreen heat was working, the screens felt room temperature (not hot), the windscreen demister was on full and both windscreens were affected. My Mechanic was at a loss to explain it.
Has anyone else seen this? Is there a fix? Rainex? Ice Away? Pledge?

[Cardinal]

Our windshields were usually lousy, and retained ice in cruise, but never in 3000 hours did I have to land with an iced windscreen. If the temp is actually -25C on the ground it's highly unlikely that one could find enough moisture in the air to thoroughly ice the windscreen.

As for starting in feather, see above reference shutting down the engine. The engine, of course, can't help but start in feather, but transitions gently and at very low power to ground idle. Starting with the prop levers in taxi avoids a large torque transient and FOD threat when they're brought out of feather later. Also note that with the props feather there is a very real risk of "cabin heating" as Beech puts it - melting the windows with exhaust gases. Our lot had a 3 min limitation in feather.

[411A]

Having flown PT6 and RR Dart powered aeroplanes before it is not all that easy to 'milk' the start lever with the PT6 as it is with the Dart.

As for starting, be sure the battery is charged sufficiently after the first engine is started, before starting the second,
If generator assist is used during starting the second engine be aware that this sometimes is rather hard on the starter-generator shaft, due to the large amp draw...better to start the second engine just with the ships battery, or expernal power, if available.
Starter-generators are not exactly cheap.:ooh:

[Dream Land]

My advice is do what you can to change levels when ice is collecting, this is typical and I don't think any windshield treatments will change it.

[boofhead]

Usually by the time it gets that cold there is no ice problem, even on the windscreen. I was surprised to see ice form. I have flown airplanes with heated windscreens previously and they usually ice up, if at all, slowly and from the edges. These ones both seemed to ice up all over, real fast, even though they had heat applied from takeoff. I guess I had better stay above 20,000. I have had to land twin Cessnas at night with iced up windscreens and it is not fun; I expected more from this airplane. Hopefully if I need it the wipers will scrape them clean.
I am enjoying the airplane, it is nice to fly.
Thanks again for the info, it is appreciated.

[Cardinal]

The worst King Air windshield is better than the best Twin Cessna windshield.

[Ian1]

Boofhead

Some answers to you questions from a LAME's point of view.

Battery is ready for the next start when the load meter drops below 40% and yes I would recomend cross generator starts but only switch on the generator once the starting engine has reached 12%Ng to reduced intial load on the running generator.
Auto feather test has been explained but you must ensure the condition levers are at low idle or the torque won't drop off sufficently to trigger the autofeather. Under the system we operate with auto feather is not a no go item. The KA does not come standard with autofeather so I don't see why it could be mandatory but that depends on the reg's you are operating under.
Never try to modulate the start with the condition lever. It is all preset at the F.C.U. Going to high idle during start will have no effect below idle speed as the F.C.U. is on the min flow stop. Going to cutoff and back to idle is a definet no no. depending on ones interpretation of the maint manual this could be taken as an inadvertant relight which requires the engine be removed and sent to an overhaul facilty.:{
Feathering after shutdown is easier on the engine but you must feather before shutdown if you want an accurate measurement of oil quantity as the oil from the prop takes time to be scavanged back to the tank.

Cheers

[boofhead]

Thanks for that; it will help me a lot to develop operating procedures and tips. I now have to teach the airplane, as well as fly it single pilot and I need this information to keep me honest.
I don't ever see the load meter over 40 percent, even just after a start. Maybe we have a good battery.
I cannot turn on the generator on the starting engine until the starter is off? Won't that drop the starter off line?
I put the first engine Condition Lever to High when using its generator to help start the second engine and put the generator on before moving the lever up. Was told that puts less load on the generator shaft?
A good point about feathering before shut down.
Appreciate the advice.

[Ian1]

Just to clarify the generator thing. I mean turning on the generator on the first engine after 12% has been reached on the second (start in progress) engine which it sounds like you are doing anyway. Like you said this reduces stress on the generator.

If you did turn on the generator on the second engine during start it should have no effect. The starter takes priority over the generator, ie the generator would drop off line not the starter. I do seem to remember this may vary if you have older generator control units, so don't quote me on that one.

Cheers

Ian

[Cardinal]

Condition Lever to high idle has nothing to do with the generator shaft, (which never break, by the way.) The objective is to turn the generato faster, so you can get more amps out of it. PT6A-67D required 65% N1 for generator loads below 50% (150 Amps.) To use 100% (300 Amps) required a minimum N1 of 72%.

Some models of the KA200 do not have cross-start current limiters. Their absence allows massive amperage to be pulled on the operating generator and dumped into the cranking starter. To avoid this one can bring the running engine's generator on after the starting engine is rotating well and the starter's draw has decreased significantly.

[boofhead]

My mechanic says the E90 (and a couple others) has the capability of starting with the generator on line. Also that it has a lead-acid battery which allows for a faster recovery. So far it has worked great for me. Apart from the climb rate (and I only use 1200 Tqe so that might be a factor) it flies well, and is very quiet. I checked the pressurization system by opening the bleeds and the dump valve (had a problem with a camera door) and the crew were much perturbed by the depressurization rate. Wooses all of them. Which brings to mind another non-PT6 question: Is it necessary to set the cabin alt control down before descent? If the alt flown has been around 15,000 the cabin is already close to sea level so a descent will simply hold that and the Diff will come back to zero even if the cabin alt selector is left at the cruise level? Can the cabin alt be flown through (negative pressure)? What would be a practical minimum Torque for descent? (I have been holding around 400 or when the gear horn sounds). Any particular emergency procedure that is popular with the sim training schools?