Guys,

Let's stop the name calling. It is pointless and demeaning. More so for the person doing the name calling then the recipient.

Tim

If you look at what happened to the two or three I've been briefed on, they lost FCUs or the prop governor control. Two wound up in the drink (ocean) with the engine still working; so, it's not just the engine. P&W doesn't count the engine shut downs for ancillary systems in their numbers. Still, reliability is very high, and even with two, as Jason has aptly pointed out, there are a lot of accidents with one working. Ted dropped his baron in the Gulf due to smoke/fire if I recall correctly.
So, a lot of this is personal preference and economics. As I said, I have time in each and see advantages and disadvantages. Currently, I really like having a twin. If Pilatus was a viable choice for me, I'd be tickled pink to own one.

Jay is an interesting fellow. Mystery. Magnificent. Envied.

He will make a claim as fact and with a straight face tell you it's gospel unless you prove him wrong. Never the other way around.

He's beyond rebuke. He's so brilliant he can't be expected to explain what he speaks.

Love you carney. Want to be like you. Who needs knowledge when you're always right.

I'll let these pages speak for themselves. Just scroll up folks, and behold

Just like dealing with my sister's English bulldog, there simply is no point in continuing on. Completely futile. No measure of kindness or conciliation is ever acknowledged. He'll do what he wants, when he wants, won't listen to anyone. In fact getting a raise out of people I think is the energy he lives on.

Carney must of humped your sisters bulldog or something, cause you sure are talking about him alot
PS. you do know he is gone now don't you?

Sorry Douglas, I just started a nickname for Jason Crandall as Jay Carney. Confusing. I was just frustrated because it felt like I was talking to the press secretary, who when caught in any type of contradiction or proven wrong has an amazing ability to dance around it. It's an art really, beyond most of our means.

But my sister's bulldog would deserve anything either carney or Crandall could give it, which I'm sure is a lot. He's hell on earth.

I was just giving you a hard time. Somebody has to do it....

IMO, you're confusing a couple different things here. To the point where you're wrong on the engineering content of your words, but still right in how things play out in the real world. That rightness on how things play out doesn't make you right on the underlying engineering.

Here's a few engineering facts:
Horsepower is torque times RPM times a constant.
Horsepower is a measure of power, which is the rate at which work is being done.
Horsepower is additive in vector fashion. Two units of X horsepower aligned are the same as a one unit of 2X horsepower.

If you look at a non-accelerated flight, the lift on an airplane equals its weight.
For any constant airspeed scenario, the horsepower from the prop equals the drag force times the airspeed. (This is the power version of the force balance. Force balance says that thrust equals drag. Power balance says that horsepower equals drag *power*, which is drag force times airspeed.)

A 1700 HP engine has the same power as 2 850 HP engines, when each is producing their rated power. If you and I are carrying a 100 pound couch together and equally, we're each carrying 50#. If two tow trucks are each pulling with 500#s of force on a car that's stuck, the total force is 1000#. Why would it be different with propellers?

So, why are twins so much slower in cruise than it seems they should be? Drag is the main factor, IMO.

Each prop disc has enormous drag. In a single, that drag is reduced (as compared to the twin props on a twin) but also that drag is partially blanketing the fuselage, making the effective drag of the fuselage lower by virtue of being in the shadow of the prop disc.

On a twin, not only do you have more prop area, none of that prop area is blanketing the fuselage, so you get the whole fuselage contributing to total drag as well.

Your PC-12 is faster on the same power primarily as a result of lower drag, not as a result of some kind of anomaly of physics related to thrust not being additive or any similar arguments.

Why does my 58P wildly outclimb my A36TN but then be just a few percent faster in cruise? Because the drag effect is lower at lower airspeeds. Climb uses lower airspeeds, so the 620 HP available (rated power) is more useful in carrying the much heavier airplane up in altitude. Once it's time to level off, the 58P has 438HP (LOP, 32 gph total times 13.7 factor for 7.5:1 engines) but is only a little faster than the 238HP (16gph times 14.9 for 8.5:1 engine) Bonanza because it's pushing the same sized fuselage through the air on a single prop disc and has way less total drag power. The 58P has a total drag of 1.85 times the Bo. 25% of the drag increase is accounted for by the ~7% higher speed, but the other 60% is accounted by the other factors.

In climb, you're using surplus horsepower to lift the airplane's mass. The original definition of a horsepower is the amount of power needed to lift 550 pounds 1 foot vertically in 1 second (or 33K pounds by 1 foot in 1 minute). The excess horsepower (that available beyond the drag power) can be divided by your gross weight and multiplied by 33K to get your airplane's climb rate.

The closest you come to being partially correct is if you were arguing that "net prop horsepower" (gross prop horsepower minus prop-induced drag force * speed) is less than half for each prop in an 850 HP/engine twin as compared to a 1700 HP single at cruise speed. I can't get to that argument from your words, even though you're coming to the obvious conclusion: that the single is wildly more efficient during high-speed cruise.

We made it 15 pages without it getting personal...

Look obviously Crandall and I disagree about PC12NG engine management, no matter what info I put in front of him, he will eventually do what he wants, perks of his situation. I encourage debates for the cause of education. Even if we disagree I'd still like to met him. This forum should be at the end of the day a bunch of friends talking airplanes. If ones thinks of Crandall negatively then fine but don't call him out on a forum. No one wants the Jeffs showing up...

After reading all of this I have come to a conclusion.

I want a Phenom 300. Wow. After Jason kept mentioning it I finally went to their website. Yep. My new lottery plane.

Do be so quick there Ken. Have you seen the new PC24? The Phenom 300 right now has no equal, however, this PC 24 is going to be very intersting aircraft and dam good looking.

They have orders for 84. It must be the bee's knee's. The PC24 could give the 350 a real run for it's money in Australia.

Single pilot a Phenom quite a handful......

Single pilot a Phenom quite a handful......

Jim,

Thank you for the detailed explanation. Where were you 5 pages ago? I still have one question using your scenario of tow trucks.

If the 2 500# tow trucks are exerting the same force on an object as 1 1000# tow truck and everything at this stage is equal,how come the 2 500# tow trucks will burn so much more fuel to accomplish the same end goal? This is the case in a twin turboprop as well as a twin jet.....

The new Cirrus Jet does 330 knots on 1 jet engine. No prop in this scenario. This is the same speed as a CJ with probably similar engines. It can't just be drag. Is an F16 just as fast as an F18?

I know you have a lot more experience with them than I do but I flew one, I have a couple thousand hours of G1000 time and I can't say it was a whole lot different than any other G1000 plane I've flown. Granted, nothing went wrong but It was pretty straight forward.

The future of aviation is 1 or zero pilots. I know several Phenom 300 owner operators that fly solo all the time.

The PC24 is gonna be awesome. But Phenom 300's have dropped a lot in price on the used market and the PC24 won't be here til 2017 so I think by the time I'm ready it'll be Phenom 300.

For all of you that think I'm just promoting my PC12...... I'm not. It has plenty of things I don't like. Withe TBM 900, Cirrus Jet, and all these new, efficient, single pilot Garmin jets coming on line (CJ3+), Pilatus is going to have it's hands full with the competition.