I'll take a good bet there will never be a 300kt PC12 or Denali. These planes are flying barn doors and unless they can get well up into RSVM space, there's just no way they can get to those speeds even with a significant power increase. You want a big comfy cabin? Pay the price in drag.

For a PC12/Denali to go from 275kts to 320kts to compete with the TBM, that's a 15% speed increase and a 30% drag increase with 30% more engine power needed. You'd need to take the engines from 1200shp to 1600hp at least. None of that in the cards as of now.

You wanna go fast on PT6? Your only option is a P180.

Yup I guess we’ll see. Next couple of years should be interesting.

Then why do they bother building new, higher HP turboprop motors?

I'm not so sure they are. What's the highest rated PT6 there is?

I'm not so sure they are. What's the highest rated PT6 there is?

The Pilatus PC21 uses the 68B at 1600 hp. Some of the helicopter engines push 1800hp.

That's thermodynamic power, not the flat rated, which is what counts when you need to overcome drag at altitude. For a PC12 to have 1600shp at it's ceiling, you're looking at having around 2400hp of thermodynamic power at SL, maybe even more.

They should just stick the Dash 8 engine, the PW100, in it and call it a day!

Basic physics of flight stuff:
- Drag is proportional to speed squared.
- Power required is proportional to speed cubed.

So:
- Speed increase = 320kts/275kts = 1.16 (16% increase)
- Drag increase = 1.16 ^ 2 = 1.35 (35% increase)
- Power required = 1.16 ^ 3 = 1.58 (58% increase)

So to make a PC12 go 320 kts without changing the drag coefficient significantly would require an engine/prop combo to make 58% more power than now. That's a pretty big bump! Range would go to hell since for a turbine fuel flow is proportional to power, too.

As stated before.... I don't think they're gonna add horsepower to the current design.

I don't think the Denali is going to be a carbon copy of the Pilatus either.

There' more to the equation than more HP. I think it's a big opportunity to build a faster SETP to compete with the jet market.

Yes, speed generally comes from significant drag reduction.

The physics of propellers is such that the SETP is pretty close to as fast as they're going to get. To make them faster requires more thrust, but as the aircraft speed goes up the blade angles also go up, and then the angles get to the point where they're not pushing the air backwards (thrust) so much as horizontally (which does nothing).

To get much beyond where prop planes are now (300-320 kts) pretty much requires moving to jet propulsion. They may still eke out a little more from turboprops, but it won't be a lot.

How does the Piaggio do it then?

I’d be happy for the rest of my life with a legit 300+ knot Pilatus.

JC,
Buy a new 930 for the majority of your flights. A used 700 with a pilot for the times you want to move 8. Won't be anymore money than a single Pilatus or close.

the 930 is 320+ KTS and the 700 without radar, flying in formation with your 930, could probably keep up...

I know I'm just silly stupid.

flying fuselage.

It's as ugly as it is mainly because the fuselage has an airfoil profile, it adds substantial amount of lift and allows them to get by with much smaller wing.

If you can't get rig of the fuselage's drag, use it to your advantage.

I doubt though Pilatus or Cessna has balls big enough to build something as ugly as Piaggio.

Disclaimer: I personally like Piaggio's look, I'd be happy to own one if I could afford it.

Buy a TBM 910/930 for you and 3-4 close friends and put the rest on an airliner.

Thats what I do.



The next TBM will be faster, bigger and more fuel efficient. Pick 1 or 2 of the 3.

Thats at sea level.
I got told by Daher the -66D in the TBM 910/930 as the highest hp @850 at FL280. On the TBM 850 its FL260.