United 328.....Holeeeeee Shit.

[MultiVerse]

Everything in aviation is covered by some form of regulation.

It explains why most general aviation planes look like they belong in a Cuban car show with designs dating back to the 1950s.

[old goat]

It explains why most general aviation planes look like they belong in the Reno Air Races with designs dating back to the 1940s.

Where they still race WWII fighters.

[Ted Striker]

It explains why most general aviation planes look like they belong in a Cuban car show with designs dating back to the 1950s.

I honesty don't know much about GA, but have been told that liability insurance has severely limited progress in bringing truly modern light singles to market - and theoretically, that's why homebuilt and "experimental" airplanes are lightyears ahead of the ubiquitous Cessnas at small airports.

[MultiVerse]

^ Insurance probably plays a big part too but an example of the regulatory hurdles a manufacture needs to overcome in order to bring new GA plane to market is the Epic E1000. The E1000 is a carbon fiber airframe single-engine, six-seat P&W PT6 turboprop that started out as an "experimental" plane back in 2004 with the intention of becoming fully certified shortly thereafter.

Epic was initially well funded only to go bust due to the cost of certification, get taken over, go bust again, until finally getting bailed out by the current ownership. In 2020, after nearly two decades, the E1000 finally became FAA type certified with planes rolling off the assembly line in Deschutes County Oregon:

Attachment 367231

[The AD]

Vaguely related question for Ted or anyone else. In the film the Great Santini Robert Duvall's F4 suffers failures of both engines. Duvall is about to eject when he sees he's over the town so he pilots the plane out to sea and dies. IRL would the pilot of an F4 with failure of both engines have any control over where the plane would crash? Those things aren't exactly gliders.

I think the airplane would still be controllable, but its descent will be dictated by its glide slope. I don't think the glide slope is going to be real great for an F-4. Still, if the airplane is at altitude it can probably fly a few miles.

And that Epic airplane ^ looks pretty cool. I had no idea there was an aerospace company in Bend. I see they've got an opening for a mechanical engineer, but I have a feeling they probably can't match my current salary.

[Ted Striker]

My 100% guess is that the F4 had a glide ratio in the neighborhood of 5 to 1 (based on what would be typical of the "man on a rocket" jet)

So about a mile distance per 1000 ft of altitude.

The bigger question in my mind would be how much control would he have? I'm pretty sure that airplane has a RAT but how limited would the hydraulics be?

[jono]

^ Insurance probably plays a big part too but an example of the regulatory hurdles a manufacture needs to overcome in order to bring new GA plane to market is the Epic E1000. The E1000 is a carbon fiber airframe single-engine, six-seat P&W PT6 turboprop that started out as an "experimental" plane back in 2004 with the intention of becoming fully certified shortly thereafter.

Epic was initially well funded only to go bust due to the cost of certification, get taken over, go bust again, until finally getting bailed out by the current ownership. In 2020, after nearly two decades, the E1000 finally became FAA type certified with planes rolling off the assembly line in Deschutes County Oregon:

Attachment 367231

The Epic grew out of Lancair, right? Cool airplanes. Maybe a little too performance-biased to make the leap to certified an easy one.

Lots of examples like that out there that used some minor shortcut along the way that could be made to work if everything was done right but wouldn't pass muster for certified. Which could be fine, but usually isn't because the investors think this beautiful airplane must already be perfect and don't plan for the redesign of some piece and run out of money. It's more a syndrome of emotional attraction to airplanes on the investors' parts than an issue of the FAA being too rigorous. The FARs should be known going in, but somehow there are a huge number of examples of undercapitalized GA efforts (many of which are borderline or actual fraud).

[Ted Striker]

Epic E1000 finally became FAA type certified with planes rolling off the assembly line in Deschutes County Oregon

That's one sexy single!

I'm guessing PT6, 280ish cruise, 25,000? The GPH has got to be a lot less than your typical VLJ, but what's the range?

Are you one of the engineers, or a future customer?

[old goat]

My 100% guess is that the F4 had a glide ratio in the neighborhood of 5 to 1 (based on what would be typical of the "man on a rocket" jet)

So about a mile distance per 1000 ft of altitude.

The bigger question in my mind would be how much control would he have? I'm pretty sure that airplane has a RAT but how limited would the hydraulics be?

See, my thought would be it would wind up in the same place whether he ejected or not , although I suppose with the canopy gone the aerodynamics would deteriorate and the ejection process might cost it altitude. But if he ejected it would have been a shitty movie, instead of one of my all time favorites (robt Duvall).

[MultiVerse]

The Epic grew out of Lancair, right? Cool airplanes. Maybe a little too performance-biased to make the leap to certified an easy one.

Lots of examples like that out there that used some minor shortcut along the way that could be made to work if everything was done right but wouldn't pass muster for certified. Which could be fine, but usually isn't because the investors think this beautiful airplane must already be perfect and don't plan for the redesign of some piece and run out of money. It's more a syndrome of emotional attraction to airplanes on the investors' parts than an issue of the FAA being too rigorous. The FARs should be known going in, but somehow there are a huge number of examples of undercapitalized GA efforts (many of which are borderline or actual fraud).

Yeah, Lancair brought composite manufacturing expertise to Bend. Even though there's a rich history of emotion clouding judgment when it comes to investing in new airplanes, those with feet firmly planted on the ground risk going broke too waiting for the FAA to approve a design.

That's one sexy single!

I'm guessing PT6, 280ish cruise, 25,000? The GPH has got to be a lot less than your typical VLJ, but what's the range?

Are you one of the engineers, or a future customer?

333 KTAS cruise (305 mph cruise, 374 mph top speed), 34,000, climb 4,000 ft/min, 1900 mi range.

I once dreamed of a TBM, now it's an Epic....

[Ted Striker]

See, my thought would be it would wind up in the same place whether he ejected or not , although I suppose with the canopy gone the aerodynamics would deteriorate and the ejection process might cost it altitude. But if he ejected it would have been a shitty movie, instead of one of my all time favorites (robt Duvall).

Yeah, the plot takes precedence over the trivia.

But in the trivia dept, it wouldn't glide on its own. It'd end up going straight down. Someone has to fly it.

[Ted Striker]

333 KTAS cruise

So it's built in a trailer?

Yeah, it's a better looking TBM or smaller PC12. I'm thinking it could be a Cessna Mustang killer if your typical stage lengths aren't too long.

[old goat]

Yeah, the plot takes precedence over the trivia.

But in the trivia dept, it wouldn't glide on its own. It'd end up going straight down. Someone has to fly it.

got it. I'm heartened to learn that there is some credibility to the plot. IRL the book's author's father, who the pilot in the movie was based on, was not pleased with the book or with his son for writing it.

[MultiVerse]

So it's built in a trailer?

Not any more! Back in the day when it was an experimental or 'kit' plane I think owners came to factory to complete final assembly of just the FAA minimum allowable percentage of parts. I'm not sure how involved the owners actually were in assembling the plane but regardless I remember reading the process was closely supervised.

[jono]

Yeah, Lancair brought composite manufacturing expertise to Bend. Even though there's a rich history of emotion clouding judgment when it comes to investing in new airplanes, those with feet firmly planted on the ground risk going broke too waiting for the FAA to approve a design.

Don't get me wrong, there's a lot of frictional losses in that process, but the availability of "weak hands" (as the BTC folks would put it) tends to pressure the planners toward optimism. Particularly, experimental composite airframes have a lot of design and construction stuff that follows the traditions Rutan laid down: basically, thumb your nose at the FAA for as long as possible in every way possible. (Huge respect for the man, but anyone who pronounces NASA "nay-say" isn't always going to make the choice that makes life with regulators easier.)

This reminds me that I designed a few weird little parts for Lancair as they were getting going on the certified project. Most memorably the key, of all things. Allegedly, a customer paid his money and was instantly pissed when they handed him a bare Medeco: "$400k and they give me a key to a warehouse--this should look like the key to my fucking Lexus!" Such weird ego games.

[stuckathuntermtn]

Not any more! Back in the day when it was an experimental or 'kit' plane I think owners came to factory to complete final assembly of just the FAA minimum allowable percentage of parts. I'm not sure how involved the owners actually were in assembling the plane but regardless I remember reading the process was closely supervised.

Woosh!

[Gepeto]

couldn't think of a better place to put this:

The Disrupter
https://simpleflying.com/aurora-d8-double-bubble/

There is a misstatement in the writeup covered in the comments:

"The article states "The natural laminar flow on the bottom of the wing and lifting body shape would reduce Boundary Layer Ingestion (BLI), meaning it could successfully fly with smaller and lighter engines." This is not correct. The laminar flow would reduce skin friction drag, a real benefit, but would not "reduce Boundary Layer Ingestion. " BLI is an intended function of this airplane design, wherein the engines would "ingest" the boundary layer. That supposedly would reduce drag and improve the propulsive efficiency of the engines."


Shorthaul jockey delight?

[jono]

That looks cool. It needs moon roofs for the P&W's though, apparently.

[MontuckyFried]

couldn't think of a better place to put this:

The Disrupter
https://simpleflying.com/aurora-d8-double-bubble/

Very cool! That said, do we already have an aircraft stoke thread? I saw a wild looking little private plane yesterday I wanted to post up but didn't wanna derail this one too much.

[Gepeto]

oh, this thread already barrel rolled a few times

[Ted Striker]

Interesting project. I doubt it will come to fruition for a number of reasons, but if some of the ideas trickle-up, that might make it worthwhile.

Though, this part is off in a few ways

the Boeing 737-800, but would essentially be a double width fuselage. It would fly 180 passengers to a range of 3,000 nautical miles; not bad for a short-haul aircraft. With its widebody configuration, turnaround at airports could be faster than current single-aisle aircraft too.
...
As with many concept aircraft, the D8 was designed to tackle the problem of carbon emissions and noise. By flying at Mach 0.74, developers believed fuel burn would be reduced by as much as 70% and noise by 71 dB compared to a standard Boeing 737-800. However, changes to the design and a desire to fly just as fast as a standard jet, at around Mach 0.82, has driven this down to a 49% fuel burn 40 dB reduction.

.82 is MMO on the 73/8 but nobody is flying around that fast. Even cruising at .80 is a little unnerving in that airplane because if you get into even light bumps, there's a good chance you're going to overspeed. .77-.79 would be typical, and even slower if the leg is long enough and/or lacks close alternates.

It's like saying a Prius will burn less at 74 mph than a Camry will at 82. Ok, but what if everyone is doing 60?

The faster airport turnarounds is pure fantasy for so many reasons. The reality is that anything non-standard would have the opposite effect.

I find the noise thing curious as well. The only times anyone cares about airplane noise is when they're close to the ground. Noise mitigation over sensitive areas is more about operation than equipment. Like the burbling exhaust everyone puts on their Japanese cars these days. You can be light-footed or wake up the whole neighborhood.

[Gepeto]

great insight...

I was piqued by the immediate future improved engine (fan) design and placement possibilities. Big potential for reductions in burn rate.

Efficiently using disturbed air?
Game Changer

eta; worked the manufacturing floor for a fan fabricator 4decades ago. Intense and astonishingly (for the times) finite processing on a larger scale. Learned a lot - really fast

[Ted Striker]

I was piqued by the immediate future improved engine (fan) design and placement possibilities. Big potential for reductions in burn rate.

Efficiently using disturbed air?

eta; worked the manufacturing floor for a fan fabricator 4decades ago. Intense and astonishingly (for the times) finite processing on a larger scale. Learned a lot - really fast

Currently all of the advances in efficiency are coming from fan/engine and wing/winglet design. And the idea of an airplane that eats its own drag is cool.

When I look at concept aircraft my first thought is always 'can it really fly?' i.e. does it exhibit at least neutral stability in all three axes without having to rely on computers or a bunch of extra shit hanging off of it? If the answer is no, then its chance of success just shrank dramatically.

It's interesting that the D8 is theoretically going after the 190ish passenger market. There have been fairly recent clean sheet designs in the wide body long haul segment (787, A350) and in regional jets, but nobody has had much interest in building a new 'big medium' (think 757), so instead we have the 321 "Neo" and 737 "Max".