BeechTalk - BT

Username Protected · **Posted:** 30 Dec 2024, 19:00

I put together some material on building and flying the Evo for a presentation to my airport pilots club that some might find interesting. Here's a link:

https://drive.google.com/drive/folders/ ... sp=sharing

Username Protected · **Posted:** 02 Jan 2025, 22:05

Even after the build is finished, the tweaking goes on. The latest improvement was to the PT6's intake plenum. We weren't happy with the original, it's just bolted together out of sheet aluminum, with square corners in the internal flowpath and leaky seams.

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Sceet hose.jpg

It took a while, and a couple of prototypes, but we made a molded carbon fiber plenum with much better sealing and internal airflow.

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IMG_5500.jpg

The difference is most noticeable on leveling off from a climb, watching the torque tick up as the speed builds. More airflow allows more fuel before temping out, so more power and more speed. GPS testing this week confirmed 306 KTAS @ 17,500', about 5 kts. faster than before in the last top speed test at that altitude. I won't be doing that often, it burns 6% more fuel for a 2% airspeed gain, and it's well into the yellow arc, but it's nice to measure the payoff for the work we put into it.

Plus, it looks way cooler!

Username Protected · **Posted:** 03 Jan 2025, 06:32

That’s really cool! I saw someone fitting a Dash 10 at advance, I wish they’d post more so we could follow that. Has anyone seen anything from JMB yet? Really curious on the final cabin and avionics designs.

Username Protected · **Posted:** 03 Jan 2025, 13:25

Username Protected wrote:

I saw someone fitting a Dash 10 at advance, I wish they’d post more so we could follow that.

That's a new build that's been on the down low for years, the owner just recently posted pictures on the EVOPO FB page.

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Has anyone seen anything from JMB yet? Really curious on the final cabin and avionics designs.

Jean-Marie, CEO of JMB, spoke at our Evo fly-in this year. They've had my plane in the booth at OSH because it's the most similar to what they're planning, especially the panel and avionics. Interior will be similar to their VL3.

Username Protected · **Posted:** 13 Jan 2025, 22:06

JMB expect to deliver their first Czech-built Evo this April. So maybe in the booth at OSH? The second is on track for July/August.

Username Protected · **Posted:** 13 Jan 2025, 22:22

Dave,
How well does the heat and A/C work? I’m sorry to ask, while I’ve read the whole thread it’s been awhile, perhaps you’ve told us whether you're using bleed air like the TBM for heat/AC. Does the heat keep up when it is -35-45C in high 20’s to 310? TBM gets cold up there particularly in back when below OVC or at night. Blanket takes care of it but……

Are you limited below 180’ currently? If not how has flight testing gone in the FL’s? Speeds, outside air temps and FF? My TBM 850 was not capable of 300KTAS at 17 like you did.

Username Protected · **Posted:** 14 Jan 2025, 01:23

Username Protected wrote:

How well does the heat and A/C work?

Works well on my plane, but I can't speak for all Evos, there's a lot of variation. And I haven't yet had it in Death Valley or the Arctic, nor have I sat in the back seat, but I haven't had any complaints since we got the bugs worked out. It does use bleed air for heat, and engine-driven A/C, like the TBM. We've hardly ever used the electric seat heat.

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Are you limited below 180’ currently?

Ha! No, I just did the speed test at 17,500 because I was at that altitude anyway for some top-of-the-IAS-range testing. Most Evos hit their best speed around FL 250.

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How has flight testing gone in the FL’s? Speeds, outside air temps and FF?

Good question. I pulled up the log from my most recent flight at FL 270 and FlySto.net says at FL 270, ISA +4C, at 55% torque -- ITT wasn't recorded but it would have been around 770C -- and 33.9 gph I averaged 287 KTAS, 8.4 nmpg. Evo IAS always reads 5-7 kts low at the top end, and GPS testing has confirmed mine is no exception, so TAS was actually somewhere in the 290s, but it doesn't matter. We just kid ourselves that we get fewer headwinds than everybody else. How does that compare with your TBM 850?

Username Protected · **Posted:** 27 Jan 2025, 00:59

I got a good tailwind Friday, but it wasn't 181 knots! What's wrong with this picture?

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IMG_20250124_143347232_HDR.jpg

Username Protected · **Posted:** 27 Jan 2025, 01:06

Username Protected wrote:

I got a good tailwind Friday, but it wasn't 181 knots! What's wrong with this picture?

Static leak maybe? Or maybe pitot tube blockage somehow? Pretty slow IAS…

I would most strongly suspect static leak from inside the cabin. Did the TAS/GS split get worse as you climbed?

Username Protected · **Posted:** 27 Jan 2025, 01:23

Username Protected wrote:

I would most strongly suspect static leak from inside the cabin.

Good thought, but I checked the copilot's instruments, on a totally separate static system, and they showed the same.

Username Protected · **Posted:** 27 Jan 2025, 07:43

Username Protected wrote:

I would most strongly suspect static leak from inside the cabin.

Good thought, but I checked the copilot's instruments, on a totally separate static system, and they showed the same.

Username Protected · **Posted:** 27 Jan 2025, 10:46

Username Protected wrote:

I got a good tailwind Friday, but it wasn't 181 knots! What's wrong with this picture?

Static leak maybe? Or maybe pitot tube blockage somehow? Pretty slow IAS…

I would most strongly suspect static leak from inside the cabin. Did the TAS/GS split get worse as you climbed?

Username Protected · **Posted:** 27 Jan 2025, 11:46

Username Protected wrote:

I got a good tailwind Friday, but it wasn't 181 knots! What's wrong with this picture?

Static leak maybe? Or maybe pitot tube blockage somehow? Pretty slow IAS…

I would most strongly suspect static leak from inside the cabin. Did the TAS/GS split get worse as you climbed?