by dnst on 12/22/21, 4:31 PM with 184 comments
by Centmo on 12/22/21, 6:16 PM
The eVTOL space is currently seeing a Cambrian explosion of different design concepts, but the first to see economic viability I think will be the simpler ones.
by aidenn0 on 12/22/21, 5:03 PM
by SkyPuncher on 12/22/21, 5:19 PM
* Scroll jacking - looks pretty, impossible to use.
* Cookie consent - It's both too large and takes to long to find the right action.
by rikeanimer on 12/22/21, 10:47 PM
Lilium is vaporware. Ask anyone who has worked in the space. Or just look at it. Or their promotional materials.
Ducted fans huh... meh. I don't think they have an interest in people understand how fly-y/hover-y things actually work.
I do applaud the investors for their vigorous desire to increase the velocity of money throughout society, it is important econometrically. Somehow I doubt they'll be happy to see their currency shredded by 36 rc brushless motors struggling to thrust an anemic wing into the sky though (before its glorious ~250km/h cruise to destination [of course])--and then ~15s landing hover.
What exciting times to fly in.
by theYipster on 12/23/21, 12:27 AM
Right now everyone is in a race to certify. I guarantee that will be the easy part. The whole list of issues this community is not thinking through and addressing dwarfs those that they are. Energy density is just the start.
For instance: Power requirements for these business models at scale will require a sudden turnaround and mass embrace of nuclear. Infrastructure build will require government investment and widespread use of eminent domain. City laws and ordinances allowing for uam flight need to be rewritten. I could go on…
Btw I am in the industry.
by w0mbat on 12/22/21, 6:43 PM
I thought that required combusting fuel and using the flaming exhaust to propel something. This is propellors in tubes.
Also this vehicle is about a third of the speed of what most people think of as a "jet plane".
by kwhitefoot on 12/22/21, 6:41 PM
Here's a better one: https://www.youtube.com/watch?v=5ukmS9ZJm40
by AeZ1E on 12/22/21, 6:11 PM
by kensai on 12/22/21, 6:00 PM
Lilium is the only company going for this distributed propulsion system with so many rotors, adding the the safety of the whole thing. Safety should be paramount! A couple of deadly accidents can literally ground a fleet otherwise.
Volocopter also tries a similar approach, but the lack of eVTOL probably makes that bird much slower than the Lilium product.
by beaconstudios on 12/22/21, 5:22 PM
by rickreynoldssf on 12/22/21, 6:49 PM
by dmitrygr on 12/22/21, 6:47 PM
Their rosy projections of how they expect battery systems to magically materialize and double in density over the next few years to make this device actually work are also quite funny.
by PicassoCTs on 12/23/21, 7:08 AM
by djrogers on 12/22/21, 5:32 PM
The idea of a 2 hour drive from a small town to the big city being reduced to a 1hr flight (with no airport - yay helipads) is already a market where helicopters are making money. Doing that in even less time, in more comfort (ugh - choppers are loud), and at lower cost per hour/mile will change things dramatically.
by HPsquared on 12/22/21, 5:08 PM
If we ever do get flying cars, they will use distributed electric propulsion.
by willyt on 12/23/21, 8:41 AM
by samstave on 12/22/21, 7:15 PM
Why are designs with multiple wings no longer developed, not just bi/tri wing planes with wings stacked, but why aren’t their rows of smaller wings, or multiple wings? Do the vortices of the trail of a leading wing fuck up themlift potential on wings behind it?
—-
We simple golf balls for greater distance through the air, and Wales see an advantage to the barnacles that grow on the leading edge of their flippers which have shown to create eddys behind the tail edge of the flipper which aids in greater vortices and greater propulsion..
Why don’t we dimple wing surfaces? Or plane bodies?
Or helicopter blades?
What happens when we simulate the leading edge barnacle bumps on the leading edge of a wing, or more aptly, the leading edge of a blade on a helicopter?
What software is used to model the airflow over a wings surface, such as solid works…
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How much overlap is there between fluid hydro and aero dynamics? (Specifically the observation of the impact to flow/eddy creation over a surface?)
by louwhopley on 12/23/21, 8:10 AM
This means, even though more inefficient than cars, you can have more “lanes” to operate in.
On roads, you have to have traffic lights and stop streets, traffic itself, and cars driving inconsistent speeds or braking when turning.
In the air this can all fall away, so people can live further away from city centres, streets can be left for cycling, and less concrete/asphalt infrastructure is required.
by Timothycquinn on 12/22/21, 6:06 PM
Considering that their marketing is not to desperate, and their releases of footage is slow and stead, I predict that they are very confident in their designs.
If I had a few million to throw around, I would definitely be investing in this company.
by amelius on 12/23/21, 9:23 AM
You cannot "innovate such that ...", you can only "innovate and hope to achieve ..."
There is too much assertiveness in this post.
by mysterydip on 12/22/21, 5:57 PM
Will this cause issues during landing? I've seen helicopters land and it can be a bumpy/sketchy experience.
by blunte on 12/23/21, 1:09 AM
At least with a helicopter you can autorotate if you lose your engine. Unless this plane will get an airframe parachute, I would not fly in it.
by wiz21c on 12/23/21, 10:07 AM
Could it be clear to everybody that this thing will require energy and thus will, in a way or another, emit somthing (either CO2 from electricity production or CO2 from the construction of means of electricity production).
Besides, why not just invest in trains ? (or lighter alternative if any)
by karmicthreat on 12/22/21, 5:53 PM
by textcortex on 12/22/21, 10:35 PM
by aj7 on 12/22/21, 10:47 PM
•High seat capacity to achieve attractive unit economics and affordable pricing over time”
devolves to
“Yes, we are building a 7-Seater!”
by twp on 12/22/21, 7:59 PM
Where is the safety margin? i.e. what happens if something goes wrong? Can the aircraft make a safe landing if the motors fail? Do the limited control surfaces give it enough maneuverability to make an emergency landing in a tight field, especially in bad weather?
tl;dr great blog, thank you for the technical insight, it sounds like you've designed Lilium for a perfect world. Popular aviation needs to have basic safety margins and there are no safety margins evident here.
by akrymski on 12/22/21, 10:27 PM
Why not use jet engines instead of propellers?
by thescriptkiddie on 12/22/21, 7:38 PM
by mrfusion on 12/22/21, 9:54 PM
by dmitrybrant on 12/22/21, 5:15 PM
By the way, hijacking scrolling behavior often breaks other things, such as searching for text in a page. Go ahead, try it, search for a term in that article.
by ncmncm on 12/23/21, 10:06 AM
Most of the profitability of an air transport, when there is any, comes from quick turnaround. Having to wait to charge for an hour eliminates any possibility of that. An alternative is to have removable batteries, so when you land, you drop off dead batteries and slot in charged ones; and charge at the airport.
A better design would have an aft liquid-hydrogen tank and fuel cell, instead of batteries, for longer range and much lower mass. LH2 would be produced at the airfield during minimum energy spot prices, and stored underground.