Starting a PT-6

[MauleSkinner]

My understanding for the reason to start the King Air with the props forward is an electrical issue.

The oil pressure gauges in the King Air are AC powered. The static inverter is not brought on line until after both engines are started. Starting with the props forward will give you an indication of engine oil pressure, as the props move from feather to flat pitch.

FYI: The King Air info above is for the 1904 A90 I have flown. Your mileage may vary.

This is correct...for the 1904 A90, although I'm not sure they had static inverters until the 1906 models came out

Later versions went to DC gages, and this isn't an issue any longer.

I would eliminate this statement, though...

This of course assumes the engine was shut down in feather, which is what is called for on the checklist.

Regardless of propeller lever position, the propellers WILL go to feather upon shutdown, as they are spring-driven that direction, and the loss of oil pressure will allow the springs to do their things.

Fly safe!

David

 

[MauleSkinner]

Some of the guys you fly with want to read the POH in flight, and find "wow, I didn't know that" stuff buried in there. I am not in that crowd however. ...

The factory wrote the checklist....I stopped trying to be smarter than them a long time ago!

Not to hijack the thread, but there are a LOT of things in the POH that aren't in the checklist...f'rinstance...in Hawkers, the book tells you not to hold the nose off the ground for aerodynamic braking, lest you screw up the main gear something awful (and trust me...the shaking IS awful). Never heard it at school, and it's not in the checklist, but it IS in the book.

A couple of our guys were trying to troubleshoot an engine indication for a long time...DoM came up with a form to fill out that was largely engine parameters. I found out about this when I got in that particular airplane, having not been in it for over a year. Had the engine issue at cruise, pulled out the form, and thought "why am I filling this out? I just push this little button here, and the engine computer takes a picture of all this stuff for a fair amount of time on either side." Not in the checklist, as the computers were a mod and the checklist was never changed to reflect the fact that the vast majority of the airframes HAVE been modded...but it's in the AFM supplement. Care to guess how many people in the company HAD read that supplement?

Long story short, I strongly recommend reading ALL of your aircraft's manuals and supplements...whether you do it at cruise or on your own time is your business. I like to do it on company time

Fly safe!

David

 

[7777]

Noise and ice are the two reasons I start in feather. If I am close to a FBO and they don't want the noise, I start in feather. If I am on ice and think I might slide, I start in feather. Other than that, I start out of feather. Just my 2 cents.

 

[satpak77]

Not to hijack the thread, but there are a LOT of things in the POH that aren't in the checklist...f'rinstance...in Hawkers, the book tells you not to hold the nose off the ground for aerodynamic braking, lest you screw up the main gear something awful (and trust me...the shaking IS awful). Never heard it at school, and it's not in the checklist, but it IS in the book.

A couple of our guys were trying to troubleshoot an engine indication for a long time...DoM came up with a form to fill out that was largely engine parameters. I found out about this when I got in that particular airplane, having not been in it for over a year. Had the engine issue at cruise, pulled out the form, and thought "why am I filling this out? I just push this little button here, and the engine computer takes a picture of all this stuff for a fair amount of time on either side." Not in the checklist, as the computers were a mod and the checklist was never changed to reflect the fact that the vast majority of the airframes HAVE been modded...but it's in the AFM supplement. Care to guess how many people in the company HAD read that supplement?

Long story short, I strongly recommend reading ALL of your aircraft's manuals and supplements...whether you do it at cruise or on your own time is your business. I like to do it on company time

Fly safe!

David

good points...I kinda exagerrated (sp?) to make my point, I do read everything I can get my hands on, but I am not up at cruise working on my Riddle Phd thesis on airflow and stall speed changes when the ice boots are inflated either.

One thing we do (that is us, not necessarily everybody out there) is put windshiled heat "ON" at 10K in the King Air and 10K turn it off coming back down. Beech claims it will "be in the next edition" of the POH but they have said that for years now.

It is not "in the book" but is something we do.

However, in most all situations, we stick to the book and try not to outsmart it (not too much...)

FLY SAFE

good thread, keep it going

 

[Striptyler]

I may be mis-understanding this, but i was under the impression in the 1900D, that, the boosted oil will always flow into the prop, and that the govoner regulates blade angle by regulating how much oil leaves the hub... Thus, ensuring a fresh, warm supply of oil at all times, during all phases of flight.

That being said, during start it wouldn't the oil be circulating through the prop dome?

eh, could be our training materials

 

[Cstyle]

I would eliminate this statement, though...
Regardless of propeller lever position, the propellers WILL go to feather upon shutdown, as they are spring-driven that direction, and the loss of oil pressure will allow the springs to do their things.

Fly safe!

David

Very True. No oil = Feather...regardless of prop lever position.

The checklist does call for the prop levers to be placed below the feather detent on shutdown.

Again...this is true of the prehistoric A90 I've flown. King Air's manfactured post WWII may have other procedures

 

[bugchaser]

Hey Avbug, I got another good reason to always start in feather. At least in an Ag airplane. If you don't have the prop in feather, when you get out to get your coffee, map or whatever, the airplane might decide to come out of feather and wander off. Can be kind of humorous when it happens to the other guy. Seriously though, good explanations as usual.

 

[avbug]

Hey Avbug, I got another good reason to always start in feather. At least in an Ag airplane. If you don't have the prop in feather, when you get out to get your coffee, map or whatever, the airplane might decide to come out of feather and wander off.

True story. Having climbed out of piston ag airplanes to load, fuel clear a nozzle, take a leak...being able to do so in a featherable turbine airplane is like a guilty pleasure.

Being able to feather on the ramp when loading means less noise, less confusion, less blast in the face for the person at the loading valve; it's nice. Same when loading skydivers or passengers or freight on and off an airplane.

 

[shiznitobam]

Jeez, just put the PCL in the start range (when the start light comes on) and then move the starter switch to auto/reset. 30 seconds later you have a started PT-6.

 

[bugchaser]

Jeez, just put the PCL in the start range (when the start light comes on) and then move the starter switch to auto/reset. 30 seconds later you have a started PT-6.

What are these things you speak of? PCL? start light? Must have been in one of those fancy people airplanes. I just lean in and hit the starter, when it sounds about right I turn on the sparkers and go full rich on the mixture or whatever they call it and then wait a while till its runnin. Works almost every time.

 

[avbug]

Jeez, just put the PCL in the start range (when the start light comes on) and then move the starter switch to auto/reset. 30 seconds later you have a started PT-6.

Most PT6 installations aren't stared like that, of course...

 

[shiznitobam]

Yeah, I was just kidding around. That is how the start on the T-6 Texan II goes. It's all automatic and guards against the "start brothers": Hot, Hung, and No. The PCL is the power condition lever or something like that, kind of like a fadec.

 

[peter185]

I think that it is the PMU or Power Management Unit that controls the start in the T-6. It is what acts like a FADEC not the PCL.

 

[VNugget]

Blasphemy! Starting a T-6 involves a primer, mixture, throttle, wobble pump, and mags!

 

[Cardinal]

A lot less shaking if you start out of feather.