- No additional draggy/heavy structures for the VTOL components, they reuse the existing wings
- No large exposed props, which have noise and hazard concerns
- Propulsors are synergistically combined with the wing upper surface, enhancing lift during cruise
- VTOL mode actuators are synergistically combined with ailerons/elevators, reducing part count
- They have wings for efficient long-distance flight (surprisingly some don't!)
- Contingency ability for runway landing if the battery is too depleted
- The aforementioned canard advantage
What makes you think it's a "total scam"?
https://news.ycombinator.com/item?id=29651504
What I was looking for is someone to say it can’t work because of the math XYZ and for a person to say back that math XYZ is wrong because of ABC and that second part never happens.
The stuff they talk about is window dressing and doesn’t answer questions like, where are your 500wh/kg batteries?
I remember when Ballon Boy happened and I took one look at that Ballon and it was instantly obvious it wasn’t carrying a kid, but apparently others were still expecting to see a kid when the balloon landed.
>My prior for VTOL these days is scam
_Why_ is your a priori expectation for all VTOL to be a scam? And does that generalized reasoning in fact apply to the specific case of Lilium?
>where are your 500wh/kg batteries
My prior is that batteries will continue on the same curve.
I gave a link in which others listed their rationale for why they don’t think it will work.
Their availability estimates for battery capacity is double the long term rate of improvement - which seems unrealistic. But yah know with enough wh/kg just about anything will fly.
> I gave a link
> my engineering mind recoils at the complexity of the design. The variable pitch blades, the adjustable exhaust nozzles, the tilt-wing vectored thrust system, etc. With complexity comes...
Hopefully this can help clear up these (hastily-Googled) concerns.
>Their availability estimates for battery capacity is double the long term rate of improvement
I do expect in the nominal case that Lilium will take perhaps twice as long to come to market, so in the end the delays may roughly cancel out. Time will tell.
Note that battery density will effect all eVTOL startups equally, so it's not really a competitive disadvantage for Lilium per se, but rather an overall industry challenge. And I agree, there are many challenges facing the industry!
Good deep discussion, thank you. Cheers mate
[1] https://lilium.com/newsroom-detail/technology-behind-the-lil...
[2] https://lilium.com/newsroom-detail/youve-never-seen-anything...
No doubt a lot of amazing things can happen with an large increase of wh/kg which is why I think it's incredibly weird that so much effort was put into things that are not that, Lilium has special investments in battery tech with Ionblox, the only interesting question to me is 'is that paying off?'. Not how much % of efficiency can be saved with a canard design - that's window dressing. Also, if they have this amazing battery tech then isn't that the most valuable thing they have and is eVTOL really the best application for it, why not double the range of electric cars instead. Even if they think eVTOL is the best use case then why not run on a skeleton crew until the battery tech arrives, or at least properly test their designs with onboard generators.
Waiting for battery tech is like waiting for engine tech and since so many engines end up vaporware so do all the nice aircraft designs dependent on them.
But sometimes new engines do deliver. The RED Aircraft V12 engines are amazing and should enabled the Otto Celera 500L to work really well. The DeltaHawk engine but they might actually end up delivering a really nice reliable engine. Part of that is a combination of long term stagnant general aviation engine technology and reduced tooling costs for manufacturing with CNCs. So there was a lot of low hanging fruit waiting to be picked.
Obviously Lilium Jets initial claims were wildly unrealistic, I think their current claims remain unrealistic, perhaps by the time they 'deliver' they've scoped it down to small hops. If they plan on selling something that can carry 7 people (they've already sold 20?) then perhaps I would believe it more if they demonstrated something working with 1 person and a whole lot of performance to spare.
That reminds me of the "V/STOL Wheel of Misfortune", a diagram of 45 different V/STOL designs, of which four made it into service.
https://www.cmlx.co.uk/hawkerassociation/hamain/wheelmisfort...
https://aamrealityindex.com/aam-reality-index
(Lilium is in the upper middle of this, FWIW)
The weight/power ratio of electrical motors is so different from combustion engines that it's a qualitative difference already. Just because nobody has ever been able to solve that problem, it doesn't mean that a lot of people won't easily solve it now.
Joby has completed many test flights that mimic its real-world route distances and energy-altitude flight regeimes.
Its flight avionics package (essential for VTOL fly-by-wire) has received FAA certification.
Related to Lilium and noise, Joby has a lower overall emitted dB energy and, specifically, a much lower dB signature in the human hearing range.
In short, they fly just fine. What makes you think things are a scam?
But mostly these things are starting to look like they are getting there.
And one could call it a scam, when tuh product you sell has nothing to do with the product you show (and no, mock-ups at airshows don't count at all), and the product you sell has, so far, no clear timeline until certification. The aerospace version of vaporware. Whether or not it amounts to an actual scam woupd be for courts to decide. Right now it looks a lot like Nikola, without the option to use a hill to fake the product demo.
As a sidenote regarding test flights: last time I checked, those were unmanned, with a demonstrator and not a prototype and no longer than 6 minutes. Which is as far from what serious people in the field call a test flight of it could be. Good for PR and investors so, it looks cool.
Also, one can make everything fly, if you put enough thrust to it. Doesn't mean you have product that can sustain a business.
scam would also involve disgruntled investors trying to sue and getting their money back. There have been a few such cases about investors wanting their money back. But the headline is that Lilium is continuing to raise lots of money and making steady progress to getting their products launched. And those court cases seem to be going nowhere so far. The nature of VC funding is of course that things don't always go to plan.
Just because this company isn't satisfying your need for instant success and instead is following an entirely reasonable path to certification, which is slow for any airplane, doesn't mean it's a scam. By that logic anything is a scam until it emerges fully designed and manufactured on the market. That's not how things work in the real world.
This thing has investors, prospective customers with letters of intent, and flying prototypes.
Nikola is actually shipping trucks at this point too. Yes, they got caught with a non driving prototype running downhill and they got punished for that and the CEO might do some jail time for that. But the thing works now and they are selling lots of trucks that actually move cargo around. A scam would have been if the thing proved to be vapor ware. As it turns out, it wasn't. It was just running a bit late.
There's a fine line between a scam and a business plan which bakes in assumptions that are unrealistic.
The big question is: have they demonstrate a loaded plane flying through a useful distance while keeping enough reserve energy for satisfying the safety requirements?
Their videos are very well produced explanations about everything but this. There's some stuff about a few changes that reduce the reserve requirements, but still, I couldn't find anything about range.