Eviation Alice (Electric Regional Airliner)

[alberchico]

Regardless about how one feels about the prospects of this project, you have to admit that is one gorgeous looking aircraft.

Edit: Flight testing was originally supposed to take place in Arizona to take advantage of the year round near perfect weather but after an investment firm acquired a large stake in the company they moved flight testing up to the Pacific Northwest so they could be closer to the engine maker to be able to resolve problems quicker. Apparently now the winter weather has wrecked havoc on their flight testing schedules. Should have just stuck to the original plan of doing all the test flights in the South.

Also it looks like the head of both Eviation and the engine maker they are using has stepped down just before the first flight. Odd timing.

I'm also surprised the prototype doesn't have the company name or logo painted on it.

Electric aviation executive Roei Ganzarski steps down from leadership roles at MagniX and Eviation

Roei Ganzarski, the former Boeing manager who went on to give a boost to all-electric aviation, is leaving his executive posts at MagniX and Eviation Aircraft.

www.geekwire.com

 

[Grey Havoc]

https://www.reddit.com/r/WeirdWings/comments/s1a4e6

View: https://www.reddit.com/r/WeirdWings/comments/s1a4e6/eviations_electric_commuter_plane_alice_doing/

 

[alberchico]

I found some interesting comments on the design of this aircraft posted on another aviation forum so I'll briefly quote some of it here:


"The configuration has a number of questionable design issues—
1) deep stall characteristics due to interaction between engine pylon and t-tail
2) susceptibility and fail-safety of thrown prop blade
3) vertical stabilizer appears undersize
4) vertical stabilizer may be flutter sensitive due to small torque cell and t-tail configuration.
NOTE: this was an issue for Honda’s first effort to design a jet aircraft.
https://en.m.wikipedia.org/wiki/Honda_MH02

It could be that the airplane is not certifiable."


This project heavily utilized the Dassault Systèmes’ 3DEXPERIENCE cloud based digital design and engineering software to fast track development. I imagine that the design was extensively tested using CATIA software to make sure that there were no glaring aerodynamic defects. So I'm not sure what to think of these potential problems. If there are any serious issues with the design I guess we'll know soon enough.

Eviation Aircraft

Eviation Aircraft wanted to design and build an all electric airplane for mid-range distances that is cost-effective and environmentally friendly on an aggressive time schedule by using the 3DEXPERIENCE platform on the cloud.

www.3ds.com

3DEXPERIENCE Enables Faster Collaboration for Eviation Aircraft - TriMech Store

This week's Product Story showcases Eviation Aircraft and their use of 3DEXPERIENCE for faster collaboration in the Cloud.

blog.trimech.com

 

[TomcatViP]

Small rudder and vertical stabilizer: the extra fuselage length might simply do the trick (think Me109).
Deep stall?!! Seriously?! I am not sure that 20+deg of alpha is the goal here. And then, what happen to a classic Aircraft that loose lift on the tail plane... It nose down.
Torque box: the engines are close to the rudders/tail assembly. The problem with the torque box is then reversed and any suspicion should be targeted in the other direction. Given the generous sizing of the tail/fuselage assembly, I would be surprised of that.
They might even play with active damping via a software trick that controls both engine's regimes (I would!).

On the contrary, rigidity b/w nose and tail should have leveraged more critics logically.

It's a beautiful plane by the way.

 

[yasotay]

It is indeed a wonderful looking aircraft. I wonder if it will make it. Customer acceptance may be a factor. The "OMG! Propellers and what!?! batteries!" crowd may be a factor. Now if the reduced cost per ticket pays out smaller routes - inter regional (St. Louis to Kansas City, Miami to Key West, Dallas to Austin) - might come back in vogue.

 

[Hydroman]

Is this aircraft EMA fly by wire? If yes, this may be the first passenger/small cargo carrying aircraft to certify an all EMA FBW type flight control actuation system, nothing certified so far by the FAA for EMA FBW.

 

[alberchico]

It is indeed a wonderful looking aircraft. I wonder if it will make it. Customer acceptance may be a factor. The "OMG! Propellers and what!?! batteries!" crowd may be a factor. Now if the reduced cost per ticket pays out smaller routes - inter regional (St. Louis to Kansas City, Miami to Key West, Dallas to Austin) - might come back in vogue.

I have to wonder of all these electric aircraft startups are ultimately hoping for government assistance or incentives to help get this industry off the ground similar to the helping hand that is given to the electric vehicle industry. Whether or not taxpayers would support that is the big question.

 

[robby.main]

I found some interesting comments on the design of this aircraft posted on another aviation forum so I'll briefly quote some of it here:


"The configuration has a number of questionable design issues—
1) deep stall characteristics due to interaction between engine pylon and t-tail
2) susceptibility and fail-safety of thrown prop blade
3) vertical stabilizer appears undersize
4) vertical stabilizer may be flutter sensitive due to small torque cell and t-tail configuration.
NOTE: this was an issue for Honda’s first effort to design a jet aircraft.
https://en.m.wikipedia.org/wiki/Honda_MH02

It could be that the airplane is not certifiable."


This project heavily utilized the Dassault Systèmes’ 3DEXPERIENCE cloud based digital design and engineering software to fast track development. I imagine that the design was extensively tested using CATIA software to make sure that there were no glaring aerodynamic defects. So I'm not sure what to think of these potential problems. If there are any serious issues with the design I guess we'll know soon enough.

Eviation Aircraft

Eviation Aircraft wanted to design and build an all electric airplane for mid-range distances that is cost-effective and environmentally friendly on an aggressive time schedule by using the 3DEXPERIENCE platform on the cloud.

www.3ds.com

3DEXPERIENCE Enables Faster Collaboration for Eviation Aircraft - TriMech Store

This week's Product Story showcases Eviation Aircraft and their use of 3DEXPERIENCE for faster collaboration in the Cloud.

blog.trimech.com

Powerful as it is, CATIA isn't used for aerodynamic studies. Of course, the appropriate 3d models developed in CATIA are used as an input for the CFD simulations that provide confirmation or otherwise of aerodynamic performance.

 

[TomcatViP]

Yes. But it's more complicated.
Fluent software (Ansys) is embedded with Catia V5. I don't know any better software for the task that was available then.
Simulation Flows is native to the Solidworks suite (but at a tremendous price). At the time, the solver was even better than what Catia had (new name from the old Cosmos brand)...
Simulia is today the integrated CFD solution for CatiaV6. Although being a generic denomination (like Cosmos was), englobing various applications, it offers leading edge capabilities in CFD:

Computational Fluid Dynamics Simulation

Steady-State and Transient Internal and External Flow Around and Through Solids and Structures

www.3ds.com

 

[Richard N]

Does anyone feel the aircraft's unusually long wingspan might present a headache for small operators like Cape Air ?

It’s a glider/sailplane wing, very high LD but only if it’s kept very clean (no dead bug/ice/ scratches/etc). What’ll be a real problem for the operators is successfully arriving at the destination or even the alternative, will depend on how clean they can keep the wing.

A normal wing doesn’t degrade much performance if dirty, maybe 2-3% whereas this one could see -20-30% which is a big impact on range.

Modern sailplanes use bug wipers to clean their wings in flight.

View: https://www.youtube.com/watch?v=xPyEDeD3Dxw

 

[alberchico]

Sorry if its a bit off topic but there is also another electric 9 seater under development that would compete with Eviation for orders. This design is much more simpler and practical for a small commuter airline. And they've started working on an amphibian version. But the fact that it has 10 engines worries me. I wonder which configuration is better, two large twin engines or many smaller lighter engines ?

First amphibious seaplane with electric propulsion to be developed

Airflow and Tailwind Air will work together to develop an electric-powered amphibious seaplane to offer a clean, safe and efficient alternative for the regional

www.aviacionline.com

Airflow is now part of Electra

www.airflow.aero

 

[Zoo Tycoon]

Modern sailplanes use bug wipers to clean their wings in flight.

View: https://www.youtube.com/watch?v=xPyEDeD3Dxw

Bug wipers were first used on sailplanes in the nineties. If you walk down the flight line of any International or National competition you won’t see many and they’re not widely used by weekend soaring pilots. Whilst they work they’re also a bunch of trouble;- turbulence can cause them to detach from the wing, conversely they can get stuck in one position on the wing resulting in a large drag penalty, and when being sent down the wing they’ve quite a limited flight speed range.

Any solution for a commercial aircraft needs to be robust and dependable particularly if it’s connected to flight safety….. which is definitely the case on being able to make your destination.

 

[alberchico]

Quick update: the aircraft is still conducting taxi tests with a planned 80 knot high speed run scheduled for today cancelled. The Pacific Northwest weather is slowing down their flight test program.

Approaching first flight, Eviation's Alice readies to test FAA

Eviation’s progress as the first all-new passenger commercial airplane exclusively powered by batteries is being closely watched as a technical, economic and regulatory pathfinder for the wider adoption of electric flight.

theaircurrent.com

 

[totoro]

Why this semi circular fuselage cross section? Does the plane perhaps still somehow feature a circular inner construction?

And if not, how does this shape affect the weight of the fuselage, considering the requirement to upkeep the material strength needed to cope with the outside/inside pressure difference during cruise?

 

[TomcatViP]

@totoro :

It must come from converging structural benefits:
- idealized single aisle cabin is triangular (head height at the center and lower height on the side where you find seats).
- no underfloor cargo compartment
- body lift
- optimized wing/fuselage attachment point with the larger dimensions of the fuselage and underfloor continuous spar.
- battery packs are large and flat (although I do remember that their intend was to have wing borne batteries) and would fit ideally with that geometry
- ground height is considerably reduced compared to a circular cross-section, easing loading/unloading operations (see post #89).

 

[Nicknick]

The last time DHL ordered an electic transport vehicle went terrible wrong... (see "Street Scooter")

 

[GTX]

The last time DHL ordered an electic transport vehicle went terrible wrong... (see "Street Scooter")

And the relevance here is??

 

[alberchico]

I do wonder how quiet this aircraft will be due to its electric motors and whether DHL will be able to operate into noise restricted airfields past curfew hours. For example the Pipistrel Velis Electro is substantially quieter than a typical Cessna, but then again it's a much smaller aircraft.

Electric planes: a quiet revolution in the Swiss skies

We take a ride on the Pipistrel Velis Electro - the world's first certified electric aircraft.

www.swissinfo.ch

These two videos show what the noise levels of a Magnix electric engine are:

View: https://www.youtube.com/watch?v=X_dnAD5TD-E&ab_channel=JonathanHemmerdinger

View: https://www.youtube.com/watch?v=poHcig9MXbs&ab_channel=AirInsight

 

[alberchico]

More images of the aircraft's taxi tests have been posted on Twitter. I highly recommend following this persons Twitter page for updates.

https://twitter.com/x/status/1484728195291041795

View: https://twitter.com/photoJDL/status/1484728195291041795

 

[Nicknick]

The last time DHL ordered an electic transport vehicle went terrible wrong... (see "Street Scooter")

And the relevance here is??

it means, DHL doesnt know what thes are doing. The Elice is a nice looking aircraft with a sleek fuselage, and I doubt that it is a good basis for a freighter. Maybe DHL will make it to a square looking ugly box like the street scooter....

 

[GTX]

it means, DHL doesnt know what thes are doing. T

I am sure you will find that they do.

 

[Nicknick]

We’ll see, in the past it was definitely not the case…

I still don’t see, how this airplane can become a freighter, with little load and internal space, small doors, triangle shaped fuselage etc.. It can’t carry more parcels than any small delivery van, despite all other drawbacks.

 

[alberchico]

View: https://www.youtube.com/watch?v=FMT6koTSOY0&ab_channel=EviationAircraftInc
.

I just realized we have not heard anything about where full scale production will occur. So far they have just leased 3 small hangars at the airfield where they are conducting flight testing to build and support the fleet of prototypes. But there has been no news of a larger final assembly plant under construction. I remember an article back in 2019 that stated that they would need another 500 million in funding to build a production line from scratch for an aircraft like this. Maybe they're hoping that once this aircraft begins a successful flight test campaign more investors will come on board.

Edit: I've found a video of the taxi tests filmed by spotters where you can hear what the aircraft sounds like, it's not quite as silent as one would think.

Aviation Event – Eviation Alice Taxi Trials

The Eviation Alice development team continue their progress towards first flight. Taxi trials have been underway and Rob Edgcumbe was there for GAR to see the latest progress.

www.globalaviationresource.com

View: https://www.youtube.com/watch?v=zUDcR9XIdH0&t=29s&ab_channel=EdgcumbePhoto

 

[Zoo Tycoon]

Edit: I've found a video of the taxi tests filmed by spotters where you can hear what the aircraft sounds like, it's not quite as silent as one would think.

Not really surprising;- Hi cruise speed needs high airspeed through the prop which on a limited prop diameter, means a high tip speed. A high speed prop tip will normally exceed an IC engine noise by quite a margin.

The relatively small prop diameter is a disadvantage of the low running overall AC architecture.

As said many times it’s all a bit of a compromise.

 

[alberchico]

Still no first flight, due to delays in taxi tests.

https://spectrum.ieee.org/eviations-maiden-flight-to-usher-in-era-of-electric-aviation

" The company has also done away with the bulky mechanical systems used to adjust control surfaces on the wings, and replaced them with a much lighter fly-by-wire system that uses electronic actuators controlled via electrical wires."

I wonder if this design incorporates any mechanical backup flight controls or did Eviation opt to go fully fly by wire ?

Not to get too off topic but it is interesting that they claim that the unusual shape of this aircraft was required to get the best possible performance but the rival design from Bye Aerospace claims to achieve the same range and payload with a more traditional layout. I guess we'll soon see who got it right.

 

[Zoo Tycoon]

" The company has also done away with the bulky mechanical systems used to adjust control surfaces on the wings, and replaced them with a much lighter fly-by-wire system that uses electronic actuators controlled via electrical wires."

I wonder if this design incorporates any mechanical backup flight controls or did Eviation opt to go fully fly by wire ?

Not to get too off topic but it is interesting that they claim that the unusual shape of this aircraft was required to get the best possible performance but the rival design from Bye Aerospace claims to achieve the same range and payload with a more traditional layout. I guess we'll soon see who got it right.

They only tell you the good news and what they want you to hear;- traditional mechanical flying controls are not overly bulky, but they’re well proven, simple, have easily managed failure modes, can be reasonably light weight and not dependent on having electricity available.

As for Alice vs Bye;- their published, Oh Wow!, performance figures are both based on battery technology which doesn’t really exist in a practical form. Alice are qualifying the battery pack separately to the airframe so as scientists discover new battery chemistries it’s an easy peasy introduction….. and if the scientist don’t then these will make a lovely pieces of sculpture.

The vast majority of an aircraft aero performance is a function of the aircraft mass, wing architecture and tail volume coefficients. Other bits of design such as the sexy looking windshield, flat bottom fuselage are gimmicks really;- it’s no where fast enough for significant body lift. The engine positioning on the airframe is largely about tolerance to failures with an equal number of advantages and disadvantages in each location.

 

[torginus]

I'm not sure how they are planning on making it economical - it only seats 9, which is way less than the 70-20 people a typical regional airliner would. But it apparently does so in opulent luxury - I can't imagine this being a cheap way to fly, and it's range prohibits it from being used as a private business jet. I'm just not seeing the market.

 

[VTOLicious]

Most likely the wide fuselage isn't for aerodynamic purpose only ( If at all?) I suspect battery containers are located in the side pockets of the cabin.

 

[alberchico]

Most likely the wide fuselage isn't for aerodynamic purpose only ( If at all?) I suspect battery containers are located in the side pockets of the cabin.

I think you might be right. Take a look at these pictures of the prototype under construction. The only thing that large space on the sides could accommodate would be the battery packs. I wonder if the wings carry any substantial amount of batteries. The second pic is noteworthy because for the first time you get a good look at the flaps and the rear cargo door. Very interesting that they are beginning flight testing in February where temps tend to be on the low side but the aircraft doesn't seem to have any anti-ice system installed on the wings. Granted Tecnam didn't install any anti-ice system on their first P2012 prototype for its maiden flight but they were flying it over southern Italy during the summer.

 

[masimaes]

well actually, eviation alice is very close to flying. its made taxi test close to 80 knots and engine run-ups. https://www.thedrive.com/the-war-zo...-for-its-first-flight-in-these-awesome-images

 

[Silencer1]

Most likely the wide fuselage isn't for aerodynamic purpose only ( If at all?) I suspect battery containers are located in the side pockets of the cabin.

When I see this aircraft earlier, my first impression was that flat fuselage bottom has been chosen as large storage for batteries. In this case the spacious side "pockets" are unnesessary, just occupies uncomfortable volumes between passenger's seats and lower fuselage corners (in cross section).

Now, after reading your opionion, I think, that such batteries' arrangement allows their easier checking and replacement inside the cabin, where volume isn't limited like in relatively small wing. If such, it's clever decision.

However, I read somewhere, that some batteries are very dangerous, if they comes to fire, due to short circuit and overheat. Does anyone knew more?

 

[alberchico]

Most likely the wide fuselage isn't for aerodynamic purpose only ( If at all?) I suspect battery containers are located in the side pockets of the cabin.

When I see this aircraft earlier, my first impression was that flat fuselage bottom has been chosen as large storage for batteries. In this case the spacious side "pockets" are unnesessary, just occupies uncomfortable volumes between passenger's seats and lower fuselage corners (in cross section).

Now, after reading your opionion, I think, that such batteries' arrangement allows their easier checking and replacement inside the cabin, where volume isn't limited like in relatively small wing. If such, it's clever decision.

However, I read somewhere, that some batteries are very dangerous, if they comes to fire, due to short circuit and overheat. Does anyone knew more?

Battery safety issues are very complex but they basically come down to two main areas: one is making sure that the battery enclosure is strong enough that any problem that comes up is isolated and doesn't spread to nearby batteries. Having electrical and thermal insulation will keep the heat from one faulty cell from impacting the other. For example, stainless steel can be used to shield the battery enclosure from other equipment.That is what Boeing did with their 787 after the JAL fire. The materials around the batteries also have to be able to withstand high temperatures.

Making sure that there is a venting mechanism to mitigate a thermal runway event is the big second issue. It is important that even in the event of a thermal runaway event the aircraft can still safely land on its remaining batteries. The FAA will not budge on this issue and rightfully so. I don't know how the certification process for electric aircraft will work, but I assume at some point they are going to have to build a mockup of the fuselage with the battery packs incorporated and trigger a thermal runaway event under controlled conditions to prove to regulators that their safety measures work as intended. Now granted I am not engineer and am greatly over simplifying things, but there are many members here that can go into further details.

That also brings up another potential issue. This aircraft carries a whopping 8,000 pounds of batteries. What if the FAA is not happy with the safeguards that are in place to protect the batteries and demands modifications that add so much extra weight that it wrecks the range and payload of this aircraft and destroys its commercial viability ? They're out of luck at that point.

This article is a bit technical but it is a fascinating read if you want know more about battery safety in electric aircraft.

A review of safety considerations for batteries in aircraft with electric propulsion - MRS Bulletin

Modern aircraft designs for “more electric” and “fully electric” aircraft have large battery packs ranging from tens of kWh for urban aviation to hundreds or thousands of kWh for commercial aviation. Such large battery packs require careful consideration of the safety concerns unique to...

link.springer.com

 

[TomcatViP]

Batteries are dangerous during crashes: any breaches of their cells can induce most of the time a dangerous self sustained fire and an horrendously deadly gaseous leak.
The best battery is the one you can drop away in case of a serious emergency (not something FAA has been looking at).

The best sustainable way in case of an emergency inside an EV aircraft today is probably to have a fuel cells driven auxiliary generator for contingency (those do exists today, at least as a refined design).

 

[alberchico]

Eviation CEO details Alice’s battery safety system, first flight ‘days away’

Previous aerospace battery incidents helped engineers better understand and prevent such risks, leading to development of technologies that will ensure the safety of Eviation's in-development all-electric aircraft Alice, says Eviations' chief executive.

www.flightglobal.com

First flight still just a few days away. We finally get some more information about the battery system.

 

[masimaes]

i swear if eviation does not test fly by this year i'm going to kill myself.

 

[TomcatViP]

You know that they still can face another battery fire?
New technologies does sometimes take an unexpected amount of time to mature and deliver.

 

[Sundog]

Sorry if its a bit off topic but there is also another electric 9 seater under development that would compete with Eviation for orders. This design is much more simpler and practical for a small commuter airline. And they've started working on an amphibian version. But the fact that it has 10 engines worries me. I wonder which configuration is better, two large twin engines or many smaller lighter engines ?

First amphibious seaplane with electric propulsion to be developed

Airflow and Tailwind Air will work together to develop an electric-powered amphibious seaplane to offer a clean, safe and efficient alternative for the regional

www.aviacionline.com

Airflow is now part of Electra

www.airflow.aero

It's not about which configuration is good, it's about which configuration is better at what? It basically comes down to the mission profile. The Eviation design is made to operate like a standard aircraft. The aircraft referenced in your links are designed more for STOL operations. Having all of those distributed motors/thrust allows the wing to operate in higher energy flow at low speeds, giving it good STOL performance. Unfortunately, unless they shut some of those motors down, the wing is still operating in higher energy flow, which means more drag. So, for a relatively short range aircraft needing decent STOL performance, the distributed propulsion system is a great way to go. However, it's not that great for high speed cruise, which the Eviation design will have relative to those shown in your links. Also, having that many motors adds a good deal of redundancy, so if they lose a motor on take off, it's not that big of a deal. Whereas, on the Eviation design, it will definitely be noticed.

 

[alberchico]

And now we have the head of the company jumping ship just before the maiden flight. I wonder exactly what problems he had that prompted his departure ? Mabye the destruction of the first prototype as well as the massive redesign to correct all of it's glaring deficiencies played a role. All in all, not a good sign.

Edit: I found these 2 excellent articles on Leeham that shed some light on the prospects of this project. It's pretty damming. Mabye he stepped down in order to cash in his stock options before the reality of how viable this aircraft is sets in ?

Bjorn’s Corner: Sustainable Air Transport. Part 4. Reality checks. - Leeham News and Analysis

January 28, 2022, ©. Leeham News: Having discussed where investments would be the most efficient in alleviating our Greenhouse gas problems and identified the low-hanging fruit, we now look at new technology airplanes that can improve the situation.... Read More

leehamnews.com

Bjorn’s Corner: Sustainable Air Transport. Part 6. Energy consumption. - Leeham News and Analysis

February 11, 2022, ©. Leeham News: In a sister article, Part 6P. Energy consumption, the deeper discussion we use Leeham’s Aircraft Performance Model from our consulting practice to generate the aeronautical energy consumption for aircraft like Eviation’s Alice... Read More

leehamnews.com

https://twitter.com/x/status/1493327009451163648

View: https://mobile.twitter.com/YohayBar/status/1493327009451163648

 

[TomS]

Eviation says (claims?) the change was part of a "planned succession process." but if so, it sounds like maybe Bar-Yohay wasn't happy with that plan.

Gregory Davis becomes Eviation’s interim CEO with electric aircraft’s first flight coming up

Eviation says Gregory Davis has become interim CEO as part of a process reflecting the transition to the production phase of its all-electric Alice aircraft.

www.geekwire.com

 

[yasotay]

This bodes ill