Yet it was accomplished in 1936 by a 500hp 9-cylinder radial, twin supercharged engine in a plywood and fabric airplane.

Could redundant electrically powered back-up pressurization ease this issue?

Could redundant electrically powered back-up pressurization ease this issue?

in my view until an independent journalist is taken for a ride in it and verifies the actual performance it is still very questionable about its practicability.

this appears to be an aircraft where the computers predict great performance but when actually built and the various systems interact the performance is far from predicted.

as a comparison, the Avanti is a fully certified known ice etc aircraft with excellent numbers and it has had great difficulty selling and it is aiming at the same niche.

As my father said until you build and actual conforming prototype and test it you really do not know what you have.

If you look at the RED engine, it is essentially 2x 6-cylinder engines sharing a common crankshaft. The cylinder banks can be run independently. It's not the same as having two redundant power plants, but it isn't just a single lump as you might imagine.

Sure, I agree, be skeptical. Aviation is fully of promises and short of delivery.

But nothing in this bird is magical or crazy, and it has flown quite a few test flights. The RED engine has been around a while and it seems to be well engineered by people who - engineer and manufacture engines. Sealand is putting one in a DHC-2 Beaver right now.

So be skeptical, but also, be open-minded. The technology progresses.

A bigger enabler will be smart autopilots like Garmin's Automoni. Epic demonstrated that in case of engine failure they could get the plane down to breathable altitude before the pilot loses "useful consciousness". When the autopilot can do that on its own the pilot no longer has to stay awake during that descent to demonstrate an equivalent level of safety.

At 50,000 feet I think the idea is to avoid death, rather than wake back up. Assuming it descended immediately upon loss of pressurization and descended at 6,000fpm (unlikely), it would take almost 6 minutes to get down to 15,000 ft, at which point I would think many people would not wake back up.

Smithsonian AIR & SPACE Magazine did a neat little article on the aircraft called Good Egg starting on Page 42. It's not the independent journalist verification that you wanted but, it was a very nicely written article.
https://www.airspacemag.com/airspacemag ... 180978683/

interesting article I hope they can make it work reliably..

Laminar flow is notorisly hard to make happen reliably.

dealing with ice could be an interesting problem. perhaps heated wings.

Gliders have wipers that run the length of the wings to remove bugs as they disrupt the laminar flow.

I would guess that would be possible but it too would have to pass certification. Assuming the source of pressurization (engine) is lost, you'd have to supply power to that system via backup battery which would be quite the load, I would guess. That battery power would have to have capacity above and beyond that which is required for critical power to systems needed. For example, the SRXX already has (2) batteries and (2) busses for redundancy. With the added requirement of power an electrical pressurization system it would likely need a 3rd power source or a massive secondary source.

Don't forget the aforementioned "high cabin differential [and] low cabin leak rate" that Epic has already demonstrated with similar construction (plus windows, so more chance of leaks). They won't be spending 6 minutes at 50K, they'll be spending that time in a cabin climbing gradually from ~8K. At your 6K fpm a descent from 50K adds less than 3 minutes to Epic's descent from 34K. Epic kept everyone not just conscious but usefully conscious for however long it took for their descent and I highly doubt that the margin is so thin that in 3 more minutes they'd have gone all the way from useful consciousness to death. But whatever the number, the point is that today's autopilot can provide more time for what is already a proven solution. Additional systems like an electric or RAT pump, or an O2 bottle, inflating the cabin for the required few minutes are certainly doable but may not be necessary.

I don't see this ultimately being used as a manned aircraft. Most likely will end up as a military drone or commercial cargo hauler when commercial unmanned flight becomes a real thing.

Don't forget the aforementioned "high cabin differential [and] low cabin leak rate" that Epic has already demonstrated with similar construction (plus windows, so more chance of leaks). They won't be spending 6 minutes at 50K, they'll be spending that time in a cabin climbing gradually from ~8K. At your 6K fpm a descent from 50K adds less than 3 minutes to Epic's descent from 34K. Epic kept everyone not just conscious but usefully conscious for however long it took for their descent and I highly doubt that the margin is so thin that in 3 more minutes they'd have gone all the way from useful consciousness to death. But whatever the number, the point is that today's autopilot can provide more time for what is already a proven solution. Additional systems like an electric or RAT pump, or an O2 bottle, inflating the cabin for the required few minutes are certainly doable but may not be necessary.

Making an engine run at 50,000 feet is not the same as building an aircraft to fly at 50,000 feet.

It is a logical step in making a vehicle that can fly in the upper flight levels.

Or possibly a long range, high-altitude military drone.