19 Nov 2025, 11:31 [ UTC - 5; DST ]
|
|
Username Protected
|
Post subject: Re: Upcoming PC-12 upgrades Posted: 05 Jun 2019, 15:01 |
|
 |

|
|
Joined: 07/19/18 Posts: 368 Post Likes: +159
Aircraft: On the hunt...
|
|
|
When did the Big Ass Fan company buy MT?
|
|
| Top |
|
|
Username Protected
|
Post subject: Re: Upcoming PC-12 upgrades Posted: 05 Jun 2019, 16:41 |
|
 |

|
|
Joined: 12/10/10 Posts: 53 Post Likes: +16 Location: KNQA
Aircraft: TBM910, PA18
|
|
|
What's up with 7 blades?!? Seems counter-intuitive to me. Does not a longer blade span mean higher efficiency? Lift to drag ratio should increase with aspect ratio. Obviously there are other factors at work such as prop diameter limits, noise, and max power that a blade can effectively dissipate. I wouldn't think power would be the limitation, though - there are plenty of large turbines driving few blades. Interesting, MT says on their website the 7 blade prop is designed for subsonic operation (duh), but at 400+knots! Somebody help my brain.
|
|
| Top |
|
|
Username Protected
|
Post subject: Re: Upcoming PC-12 upgrades Posted: 05 Jun 2019, 17:33 |
|
 |

|
|
Joined: 06/12/18 Posts: 15 Post Likes: +6
|
|
Username Protected wrote: What's up with 7 blades?!? Seems counter-intuitive to me. Does not a longer blade span mean higher efficiency? Lift to drag ratio should increase with aspect ratio. Obviously there are other factors at work such as prop diameter limits, noise, and max power that a blade can effectively dissipate. I wouldn't think power would be the limitation, though - there are plenty of large turbines driving few blades. Interesting, MT says on their website the 7 blade prop is designed for subsonic operation (duh), but at 400+knots! Somebody help my brain. I imagine their is greater efficiency in increase the number of blades. I believe the prop diameter went down when they switched from 4 to 5 blades so that probably decreased the noise as well since the tips of the blade weren't moving as fast?
|
|
| Top |
|
|
Username Protected
|
Post subject: Re: Upcoming PC-12 upgrades Posted: 06 Jun 2019, 07:06 |
|
 |

|
|
Joined: 05/23/08 Posts: 6063 Post Likes: +715 Location: CMB7, Ottawa, Canada
Aircraft: TBM - C185 - T206
|
|
That is ridiculous. Ground handlers screws up the 5 blades all the time on the TBMs, imagine 7. The MT 5 blade on the TBM is shorter and also slower. The 5 blade Hartzell is the same lenght as the 4 blade and the same speed or 1-2 knots faster. It does climb faster and a little bit quiter in the cabin. Those TPs are quiet with the existing 4 blades. It as nothing to do with sound. Username Protected wrote:
_________________ Former Baron 58 owner. Pistons engines are for tractors.
Marc Bourdon
|
|
| Top |
|
|
Username Protected
|
Post subject: Re: Upcoming PC-12 upgrades Posted: 06 Jun 2019, 17:59 |
|
 |

|

|
 |
Joined: 10/05/11 Posts: 10261 Post Likes: +7329 Company: Hausch LLC, rep. Power/mation Location: Milwaukee, WI (KMKE)
Aircraft: 1963 Debonair B33
|
|
Username Protected wrote: Maybe there's someone on here that understands the physics and can explain it to us A- students.
Take some time to review this graph. This sums it up well. The graph is used (in my world of factory automation) to show people how much money can be saved running centrifugal pumps or any type of fan using a variable frequency drive to adjust speed based on demand/requirements. Many systems are sized for worst case conditions. It's not unusual to have way more flow than needed when a system is new, demand is light, and/or filters are clean. Just a 20% drop in speed is nearly a 50% drop in the power required. Airplanes going thru the air are similar in behavior. There's also something to be said about prop blade angle, too, but that's a longer discussion about which I know even less.
Please login or Register for a free account via the link in the red bar above to download files.
_________________ Be Nice
|
|
| Top |
|
|
Username Protected
|
Post subject: Re: Upcoming PC-12 upgrades Posted: 06 Jun 2019, 21:59 |
|
 |

|
|
 |
Joined: 03/03/11 Posts: 2061 Post Likes: +2141
Aircraft: Piaggio Avanti
|
|
Username Protected wrote: Maybe there's someone on here that understands the physics and can explain it to us A- students.
Drag is a square of speed. This tells you all you need to know. Even if they made the pc12 hit 300kts, that would be the ad number. They don’t cruise around at the speeds in the ads. I love the plane but was surprised by how slow it is when I flew it. Flight aware supports this too before anyone posts about their pc12 ripping around at 280kts all day long.
|
|
| Top |
|
|
Username Protected
|
Post subject: Re: Upcoming PC-12 upgrades Posted: 07 Jun 2019, 00:14 |
|
 |

|
|
Joined: 11/22/12 Posts: 2923 Post Likes: +2898 Company: Retired Location: Lynnwood, WA (KPAE)
Aircraft: Lancair Evolution
|
|
Username Protected wrote: Drag is a square of speed. True, but power required is a cube of speed. Pilatus claims 285 for the latest PC-12, with no airframe changes pushing that to 300, 5% faster, would require 16% more power. From the current 1,800 hp (thermodynamic) engine derated to 1,200 hp they'd need to go to a 2,100 thp engine derated to 1,400 hp. Big step.
|
|
| Top |
|
|
Username Protected
|
Post subject: Re: Upcoming PC-12 upgrades Posted: 07 Jun 2019, 05:12 |
|
 |

|
|
Joined: 06/12/18 Posts: 15 Post Likes: +6
|
|
|
Can one of the owners give some real world cruise speed numbers that you see on a regular basis?
|
|
| Top |
|
|
Username Protected
|
Post subject: Re: Upcoming PC-12 upgrades Posted: 07 Jun 2019, 05:58 |
|
 |

|
|
Joined: 03/09/13 Posts: 929 Post Likes: +472 Location: Byron Bay,NSW Australia
Aircraft: C525,C25A,C25C,CL604
|
|
Username Protected wrote: Textron will bring the Denali, but people are going to be very, very leery of the engine...... Yeah after getting the F%#$ around investing in new technology (Tamaracks) I’d be cautious too. Lesson learnt. Andrew
|
|
| Top |
|
|
Username Protected
|
Post subject: Re: Upcoming PC-12 upgrades Posted: 07 Jun 2019, 08:16 |
|
 |

|
|
 |
Joined: 01/29/08 Posts: 26338 Post Likes: +13085 Location: Walterboro, SC. KRBW
Aircraft: PC12NG
|
|
Username Protected wrote: and over 1,000 NM, that 15 kts saves you all of what... 13 minutes? It's more than 15 knots as I never see 285 in my Pilatus. I get 275 in the winter. 265 in the summer. I'm fine with 265 until I get myself into an 80 knot headwind. Getting 300+ TAS would really help the westbound in winter flying. All other missions 265-275 doesn't bother me at all.
|
|
| Top |
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot post attachments in this forum
|
Terms of Service | Forum FAQ | Contact Us
BeechTalk, LLC is the quintessential Beechcraft Owners & Pilots Group providing a
forum for the discussion of technical, practical, and entertaining issues relating to all Beech aircraft. These include
the Bonanza (both V-tail and straight-tail models), Baron, Debonair, Duke, Twin Bonanza, King Air, Sierra, Skipper, Sport, Sundowner,
Musketeer, Travel Air, Starship, Queen Air, BeechJet, and Premier lines of airplanes, turboprops, and turbojets.
BeechTalk, LLC is not affiliated or endorsed by the Beechcraft Corporation, its subsidiaries, or affiliates.
Beechcraft™, King Air™, and Travel Air™ are the registered trademarks of the Beechcraft Corporation.
Copyright© BeechTalk, LLC 2007-2025
|
|
|
|