Ah, that would be the dreaded 35 motor approach. Even scarier: two motors out on the same wing, so now down to 34 motors.

QUOTE]Auto....Auto......wanna see an AUTO[/QUOTE]

Er its called ballistic recovery parachute system as fitted to many LSA and larger aircraft. Cirrus C 172 C 150 etc etc.

Been around since the 80's and so far used successfully about 250 times.

Even works when the wings drop off obviously.



You blokes need to get out more often.:O:O

Not without something in the video to scale it, no. The dynamics of the lift of were all wrong - something weighing over a ton wouldn't wobble in that way. Also I can't see how ~2000lbs or more of vertical thrust could be achieved with so little noise and so little evident jet-sheeting over the surrounding grass.

It looked and sounded like a model weighing perhaps 10-15kg with an array of standard electric ducted-fan units totalling somewhere in the region of 3-4kW. If it WAS bigger and capable of carrying a couple of hundred kilos of self-installing flight control system then show me the paperwork that would be needed to test fly that under remote piloting (because that's not a trivial thing in an EASA country). Then perhaps I might be less sceptical.

PDR

When viewed full-screen, you can see lots of little wobbles in the pitch and yaw plane - a machine of real size and weight (with the subsequent inertia in pitch and roll) could not wobble that fast without some serious stresses.

Check video at 1:24 for weight indication
 

Mick,

If you know or have access to the actual flight vehicle dimensions, just provide them. It may be capable of fitting two passengers, but it appears smaller than he non flying mockup shown earlier in the video.

Regarding the flying aircrafts actual weight. Stop the video at 1:24 and look at the landing gear being used. The three thin curved hoops of either composite or metal could not support a realistic weight of a two passenger aircraft.

And why no wheels? I know it's supposed to be a VTOL aeroplane, but those silly little skids will make it a right pain to move around on the ground (like helis with skids).

Sorry, but no one would get that far with a project with that kind of schoolboy error. It's making the F313 look credible...

PDR

OK, I relooked at the video and a number of questions came to my mind.

1. why did it take off from a taxiway and not from either the runway or a helicopter landing pad?

2. for a first flight why was there no flight data probes? surely you would want to know the environment that the aircraft was flying in?

3. Why did they not list the airport that they took off from, every other first flight video tells you the time and date and where the first flight occurred? Was this flight legal?

4. When it took off it had aGoProo mounted at each wing tip let later on in the video there was one missing, did it loose a GoPro if not was it the second flight that we saw later on in the video?

To be honest there are too many questions and not enough data to make those questions disappear.

Fats

Re the previous posts, sensible questions from Ppruners, which have been put to the company on social media.
They have replied directly, saying the video was edited from more than one flight during their test program and the craft was their full size two seater.

This conversation raises the question of the definition of a "prototype".


Mickjoebill

Weight and dimensions please
 

Mick,

Weight and dimensions please. Then the truth is clear.

You mean an 11,000 lbs with 1,100 SHP engines helicopter compared to a 23,000 lbs gross weight aircraft and rated jet engine?
Yeah, the noise may be different.

ESA are involved. I doubt they'd put up with fake videos.
ESA website

The ESA web site so helpfully referenced says the concept has been 'validated ...with several scaled prototypes weighing 25 kg'.
It goes on to say that Lilium is now developing its first product, a two seater ultra light...
I think that settles the matter, the video is of one of the prototypes.

A Manager at Lilium HQ have said it was their full scale 2 seater used on the maiden flight video and that the video contains pictures from multiple flights.

You could estimate the craft dimensions from the drone shot with the tech laying underneath.

I'll ask about weight but don't hold your breath:)
One assumes their plan for world domination has factored in the prospect of evolving battery efficiencies.

Pity they didn't show an unedited flight from takeoff to landing. I've suggested they release an unedited shot from the camera drone that was also airborne.


Mickjoebill

That's what also caught my eye. It's unfortunate that this start-up felt compelled to release video of a vehicle that clearly does not conform to a production configuration, making a very brief flight that demonstrated some potential stability/control issues.

Thanks Mick
 

Thanks Mick,

I agree. I won't hold my breath waiting for an aircraft weight.

Did they claim that it was a production model? I don't think so.

Similarly, the flying bedstead wasn't a production model Harrier.

"A Manager" - why no name? Despite the claims that there are tens of people working ion this project you only ever see two or three. Hardly a hive of development activity.

Ah, but lying under what? That looks like the mock-up, because no one puts that much fit & finish effort into a flight-test sample. Also if it's a flight-test aircraft where are the datum marks, instrumentation probes etc etc?

Current [sorry!] batteries are very efficient - what they need is much higher energy density (especially with respect to mass), not efficiency.

So straight questions:

1. Did this (these?) flight(s) take place in Germany?
2. If so where are the notams for the area concerned that would be needed to operate a remotely piloted vehicle with in AUW in the thousands of pounds region?
3. In Germany an RC model weighing more than (IIRC) 5kg needs various approvals both during construction and to fly. Alternatively a "commercial" remotely piloted vehicle would need certification to something akin to CS22 with a certified design organisation and an operating organisation holding approvals to something akin to the UK's Part 8(a)1. Who holds these approvals, who undertook the certifications or were they flown illegally?

If they could just provide some pretty simple and non-confidential answers they would blow our scepticism out of the water...

PDR

PDR,
It was, apparently real person with a real job title in marketing who responded to me by email.

So both head of marketing and the co-founder are saying the same thing, that the video was of their full size 2 seater.


Mickjoebill

Both Nigel Farrage and Boris Johnson said that we would save paying £350m a week by leaving the EU. Both of them saying the same thing didn't make it any truer.

I'm not accusing anyone of mendacity - I just find it strange that the identified inconsistencies could be easily and simply resolved with almost no effort, but they have chosen not to do so.

Look, I don't know if you've ever tried to integrate "remote piloting systems" into a full-size airframe with a view to legally flying it (even in very restricted tests) European airspace, but I have been involved in it. It's non-trivial. In my view (others may have different views and I may even be wrong) doing the initial tests "unmanned" makes it harder rather than easier, and I simply don't see any of what I would expect to see as the minimum prerequisites in any of the information and claims they've shown to date.

Never mind the picky little detail of how the aerodynamics of that configuration are supposed to work in wing-borne flight.

I'm cutting them some slack - I have assumed that things like the variable nozzle systems needed to allow the same fans to work efficiently for both hover lift and 200mph flight are something they'll add at a later date. But there are just too many details that simply don't add up.

Want one more? Why the deeply-tinted windscreen glass? How's that going to work in marginal viz? Why bother having it on a flight-test specimen...

PDR

The flight took place at the Grob Airfield im Mindelheim.

Jo

Indeed, the slow speed flight dynamics certainly do indicate that this scaled prototype in the video was 25 kg

Some great pictures of it in a British newspaper site about a year ago.

And apparently it will be on sale in 2018

Lilium the world's first electric vertical take-off and landing jet | Daily Mail Online

One thing occurs to me - are those front pods or whatever they are called retractable into the front fuselage sides, as one photo implies?

If so, where are your legs?

Yeah, been asked before - when the "pods" retract;

1. Front seaters' legs get crushed;
2. Retractable front wheel assembly gets mangled; and
3. Machine pitches nose down due to the whole structure c.g. being in front of the lifting surface.

Well you don't get all that innovation without some downsides...

PDR

So in summary what we are seeing is a "scaled prototype" (ie not full size) weighing 25kg (not something with a 200kg payload or a 300 mile range).

So it's an RC model aeroplane, as we said. Its power system, energy storage and structure will not be representative in any way. Its control system might employ similar general principles, but won't use the same hardware. As such it matters not whether it's a model of the 2-seater or the 4-seater; it's still just an RC model.

And more to the point it's only shown in jet-borne flight; there is no video of it in wing-borne flight (whether with the front fan units deployed or retracted) so it does nothing to address the fundamental questions we have been asking about how it is to work aerodynamically.

I believe our scepticism is growing rather than receding.

PDR

Reminds me of the old Tucker automobile, where he originally planned for front wheel fairings to turn with the wheels and thus have the headlights mounted on them follow the direction of travel, but had to settle for a single headlight in the centre of the bonnet that turned with the steering wheel.

That seems like a reasonable number, which should be quite achievable using the foam (either sheet or carved from a solid block) construction used for millions of RC planes. If you wanted to do a mock-up to show to potential investors, as well as having the ability to do demo flights, that would be a good way to start.

Stick a couple of big-ish (110 - 130mm) electric ducted fans in there (up to around 8kg thrust each at 6kW; 5kg would be more common in the cheaper models) and you should be able to fly that around very nicely - at least when there's no wind.

So who is digging a deep hole for themselves, Ppruners or Lilium?


Lilium Facebook post from co-founder Patrick Nathen,
"As a founder, I can guarantee on behalf of our amazing investors and all you people out there, we did NOT use CGI or a size scaled model. This is the original size of our previous two-seated concept."

Email from Marketing manager in response to edited video.
"I can confirm that it is the full scale 2-seater.
We are running a test flight program, which means, we are testing it more than once.
We can start and land anywhere, doesn´t have to be exact the same spot, right?
Best, Mareike

Mareike Mutzberg
communications manager"

A remote test flight, apparently not above 100 feet, on "private" property of a fly-by-wire craft, backed by ESA and funded by the founder of Skype is not far fetched. Especially since they were test flying several scale models throughout 2016, videos of which are on u tube.

The thing is just a drone on steroids so remote control is embedded in its DNA.
They plan for it to be autonomous, so there is less to be converted.

Sure, they have shot themselves in the foot by labelling the video a "maiden flight" when it is a glossy compilation of several flights. They seem reluctant to release a continuous unedited shot of a flight which would adress the scepticism that scale models were used.

But it would be very silly of lillium to further mislead the public by making the statements quoted above if they were not true.

Has anyone found a report from a journalist who eye-witnessed the test flights?

Ppruner scepticism up to a point (!) is encouraged, given the radical design and the "forward looking" specification and performance of the craft and the unsatisfactory presentation of the test flights.

Mickjoebill

It's a bit of a worry that the design team did not notice that small problem right at the start.
I expect the next announcement will be something like
"Yeah, that one was just the concept. The production version will have extra wings... and wheels.... and a big engine... and...err, lots of other stuff" :E

The airfield in Tussenhausen Germany can be viewed on Google Earth.
According to google earth the taxiway the craft lifted from is around 6.5 meters in width.
Video from a few angles indicates the wingspan of the lilium craft is a similar width to the taxiway.

So an extraordinary achievement if the craft has a wingspan of over 6 meters yet weights only 25kg:)

Mickjoebill

I wonder how it taxied from the hangar to the runway?

But if it is an air vehicle of significant size and mass (larger than the germa large RC model rules would cover) it would still require the airfield and surrounding area to be notam'd - it should be easy enough to find that notam to add some substance to the claims.

Stunning! I must try that as a safety case argument:

"Certification, design standards compliance and range airspace sanitation/segregation not required because remote control has been embedded in the vehicle DNA".

Yep, I can see the airworthiness authorities signing off on that!

Making unsupported and expansive claims to attract inward investment is hardly a novel practice.

PDR

Indeed - that was one of the many as-yet un-answered questions asked in the preceding pages.

PDR

The whole "retractable forward lift motors" thing seems to be a feature of this "flight test model" only. The other concept picture show a large and blown foreplane, so I'm confused. Are they saying that this sample is ONLY for jet-borne flight, and the one that does wing-borne flight will have a foreplane? Why build two that are different?

The CG issue perplexes me. It is claimed that the final product is a 4-seater, with all the seats forward of the mainplane. That's a load which could be anything from (say) 100kg to 400kg. Now if there is a large foreplane it's conceivable that the CG lies somewhere in the cabin area and this variable load could be accommodated.

But if it is flown with no foreplane then the CG will need to be somewhere around 15% MAC (typical stability point for an unswept "plank" tail-less with a reflexed wing section to give the favourable pitching moments). That means that the occupants will all be ahead of the CG. Now if we assume there is a vast battery weighing more than a brace NFL quarterbacks which is mounted right at the "back end" (please stop me if this techie jargon is getting too complicated) that would balance the occupants. But how would it cope with the massive variations in occupant weight? This doesn't stack up.

The website talks about the final vehicle will charge overnight form a normal mains outlet, and then defines a mission profile of just over an hour's duration. So let's be generous and say a 12:1 charge/use ratio. In the UK/Europe the most you can take out of a mains socket is 13A, which gives you a smidge under 3kW. So if we ignore charging losses that tells us the average power consumption across the mission would be no more than 36kW - 47bhp.

Does it sound reasonable that a vehicle could carry 4 people and luggage at 180mph for 200 miles with vertical take off and landing on an AVERAGE of 47bhp - less than a typical VW conversion in a Turbulent?

There are other techie howlers on the website as well, but the man's down so I'm stopping the kicking.

PDR

Well, either it will fly or it won't. If the above sceptics are right, and nothing beyond a scale model ever flies, we won't hear much more about it. If, on the other hand and in the fullness of time, a full size airworthy aircraft surprises us all with new and astounding technology, the above pruners will all have to eat humble pie. Stranger things have happened and time will tell.

This one looks a bit more like it will ... ummm ... take off?

Aurora Unveils New eVTOL Aircraft at Uber Elevate Summit

I don't believe the Firefly ever flew. Sorry for the response to an old post, I'm behind here.

I will say that anything will fly if you get the disk loading low enough. Asking about size and weight are entirely appropriate.

So a year after their claimed date for a manned flight they have managed instead to fly a large drone that looks like the concept but cannot carry out the functions of the concept. Certification in 2018? :rolleyes:

Electric drones doing VTOL is decades old news. The concept was for this thing to carry people and also the wings to fold away so it could drive along the highway. This "first test flight" was actually an RC model aircraft that could do neither. Boring.

According to their new timeline, first manned flights will take place in 2019 now. Well, I do remember the old one you´re referring to ;-)
Additionally, the new pictures don´t show the slightest chance of retractable "wings". Maybe they came across some serious physical issues with CG? On of the founders being an (inactive) glider pilot, I would have expected this encounter a few years earlier ;-)
What remains, is an electrical driven VTOL aircraft.
A five seater Lilium will presumably be bigger (in terms of wing span) than a comparable 5 PAX classical Heli in rotor diameter. I wonder, how they will get their "Lilium Pads" in downtown Manhattan...


But hey, the´ve got their investors, they seem to have some App (or at least some true image manipulation geeks).
Isn´t that all you´ll ever need in modern business?
:E


Thracian

For those that can be bothered, there's a different video on Liliums Facebook page which shows a couple of different camera angles and some extra detail.

As certain posters seem to be utterly convinced the whole thing is a scam, I'll leave them to find it themselves...