Model X mules show signs of a new spoiler?

[AnxietyRanger]

Good guess, I hadn't thought of that. I think you may be right. The way the window abruptly ends (at ~90 degrees) near the rear "spoiler" doesn't seems likely, and the more rounded feature under the wrap is likely the true edge of the window.

There are abruptly ending rear windows in some cars, though, with automated spoilers - at least Panamera is very similar:

Why would they wrap a thin strip at the base of the rear window? What could they possibly want to hide there? AnxietyRanger?

Good discussion, thank you guys.

I think we need to remember, when we first saw this setup - it was on a black mule (may be the same we are seeing here but had different bumper) - an additional piece covering the rear part, the middle one here:

Also the white one had something there once:

That said, I think the answer is one of two:

1) Both versions (black and white) that show extraneous parts in the spoiler sector are merely camo to make the mule look like the original 2012-2013 prototype (which is topmost in the picture above) and hide this change (much like front roof is camoed to disguise the fact that there no longer is a central beam between A pillars on the mule). In this scenario the latest black mule would actually reveal the final or near-final version of the rear window.

2) None of these mules show the exact final version of the rear spoiler area, but may show some camoed or obsoleted development versions instead. Final might be something completely else.

I'm not fully convinced the white camo with depressions in the rear spoiler area is merely camo. It could be the underbelly of what is showing on the black mule above. Maybe they were testing an extending spoiler or a rear wiper at some point and this is related.

Of course, it all could be just camo or obsoleted parts - even the latest glass-looking one.

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There is still something showing through and the window bending a little weird where the camo used to be. Is it a full piece of glass for sure, or could it still be a sign of camo or something more dynamic than merely a big window?

Of course whatever showing through could merely be interior camo/tape or a trunk cover showing through.

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What if the rear glass is two-part, hiding either an automated spoiler and/or a rear wiper under the horizontal piece of glass on the lower end. That would explain why the edge of the glass looks like it is made from two pieces, although I must admit the central seam is almost seamless at least from this distance, if this theory is to hold water. A separate part on the lower end would also explain why the trees reflect so differently from that section (although being concave could explain it too).

 

[vandacca]

There is still something showing through and the window bending a little weird where the camo used to be. Is it a full piece of glass for sure, or could it still be a sign of camo or something more dynamic than merely a big window?

Of course whatever showing through could merely be interior camo/tape or a trunk cover showing through.

View attachment 80173

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What if the rear glass is two-part, hiding either an automated spoiler and/or a rear wiper under the horizontal piece of glass on the lower end. That would explain why the edge of the glass looks like it is made from two pieces, although I must admit the central seam is almost seamless at least from this distance, if this theory is to hold water. A separate part on the lower end would also explain why the trees reflect so differently from that section (although being concave could explain it too).

The latest photos of the Black "Mule/RC" definitely shows like the rear is one piece of glass, with a slight change in angle near the base of the window (the place where AnxietyRanger labelled, "Weird turn in window edge"). This change in the window angle may be there to simply allow the air flow to separate from the vehicle, so if there is a rear window wiper, the air flow will flow above the wiper without being disturbed (better aerodynamics). But, I can't see where they would mount this wiper.

Also in this latest Black "Mule/RC" photo, the "Horizontal line / edge" does appear to be coming from within the vehicle, which could simply be an interior security shelf.
In the older White Mule and Black Mule photos, it looks like there is a wrap at that location.

 

[AnxietyRanger]

The latest photos of the Black "Mule/RC" definitely shows like the rear is one piece of glass, with a slight change in angle near the base of the window (the place where AnxietyRanger labelled, "Weird turn in window edge"). This change in the window angle may be there to simply allow the air flow to separate from the vehicle, so if there is a rear window wiper, the air flow will flow above the wiper without being disturbed (better aerodynamics). But, I can't see where they would mount this wiper.

Also in this latest Black "Mule/RC" photo, the "Horizontal line / edge" does appear to be coming from within the vehicle, which could simply be an interior security shelf.
In the older White Mule and Black Mule photos, it looks like there is a wrap at that location.

It could simply be an interior shelf - and actually at first I thought that must be it.

But looking at it closely, there are three potential signs that still make me wonder if this lower part of rear window isn't "active" somehow, be it an extending spoiler like Porsche Panamera (only more elegantly disguised) and/or a rear wiper.

Elon, if you're reading and messing with us, just put a smiley on Twitter.

 

[AnxietyRanger]

Now, Tesla needs to implement this!

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The new mule also has a new rear window shape overall.

It is evident the old "spoiler ridge" actually now just pretty much sits level with the new rear window which is raised a lot in the corners. It used to be recessed, someone thought an old part perhaps.

It seems more likely to me now that the rear is still made up of two pieces (of glass?), although of course it is hard to say if that has any function beyond aesthetics.

In any case, it seems this particular mule may give us a bit newer hint of things to come than the previous one(s).

 

[vandacca]

But looking at it closely, there are three potential signs that still make me wonder if this lower part of rear window isn't "active" somehow, be it an extending spoiler like Porsche Panamera (only more elegantly disguised) and/or a rear wiper.

AnxietyRanger, I think you're really losing it. "active" rear window??? Your imagination is getting the better of you. That is clearly a single piece of glass (with no discernable seam). There is nothing "active" about that rear window.

 

[AnxietyRanger]

RangeAnxiety, I think you're really losing it. "active" rear window??? Your imagination is getting the better of you. That is clearly a single piece of glass (with no discernable seam). There is nothing "active" about that rear window.

Don't hang up on words, though. By active I merely meant, could there be some moving feature in the rear spoiler area.

Besides, I am not saying there is. We have no proof of anything like that. I'm not saying it necessarily moves at all. The concept where it splits to reveal a wiper like that was obviously made in jest. It could totally cram snow from the rear window inside the split crack...

But it still looks to me like the rear window could be made of two parts. That is all I think there may be proof for. There could be structural reasons for it, or it could merely be showing a development step and final car could have one piece there. Of course, it could be a single part too.

I still see a similar rectangular shape on the lower edge of the left image, as I do on the right image - the quality of the photo and the angle is such that I am not fully convinced they couldn't remain separate pieces, just a more polished total with new upper part of the rear window:

Here is where I think there still could be a "discernable seam", hidden by the angle of the photograph, angle of light, low quality and compression, camo darkening the rear window, and a good job by Tesla making it look fairly seamless:

Again here is a Porsche Panamera with two part rear glass in similar fashion that could be employed here. It looks very seamless in this photo, but in reality there are seams - in fact, this "active rear window" actually extends upwards and splits to the sides too:

Here another Panamera rear window version which is even more seamless when looked closer. The only way to really tell from that angle are the sides, the horizontal seam looks very faint. The fact that the car doesn't have camo, or isn't moving, or photographed through a dirty window also helps.

A "usual" reason for a split rear window would be an active spoiler like on the Panamera. Model X has a fairly rounded shape like Panamera, and aero-wise which might benefit from that, but need a spoiler at speed. Only reason why I still toyed with the idea there might be some kind of a washer feature, of course, is the speculated presence of a rear DRIVE PX mirror-replacing camera that might need something for that.

That said, it is purely speculative what, if anything, a two-part rear window on the Model X means. I'm just not convinced the rear window is a single part on that mule yet, factually.

 

[AnxietyRanger]

The main reason I'm not convinced the horizontal line that can be seen on the lower part of the Model X rear window is an interior shelf and/or edge blackening, is because it extends all the way to the physical edge of the glass. If it were an interior feature showing through the window, the line would likely end before the physical edge of the glass.

Compare these shots, with the Model S rear window and its edge blackening and rear shelf and/or seating showing through the glass on the left. And while there is edge blackening and interior features that show horizontal lines through the glass, there is no line that would extend from end to end on the glass on the Model S, other than the actual physical edge of the glass. Yet on right, on this Model X mule, there is a clearly discernible line extending from edge to edge of the physical glass, including a clear change in the way it reflects light on the right side where trees are reflected and a leftmost edge not as clean as the upper window edge:

Only reason, that I can think of, it makes sense for the line to extend to the physical edge of the glass is either that it is a separate piece of glass or a very specific camo.

Now, a production model might of course have a one piece rear window, even if the mule had two pieces - unless, of course, there is a necessary reason for a two-part rear window, like a spoiler Panamera style.

 

[Earlian]

From all last pictures and conclusions, is one handwriting to find everywhere.

Tesla is trying to give the passengers the most panoramic 360 view possible.

Glass all over and trying to maximize this glass parts, by reducing all kinds of pillars or trim.

Thinking of that spoiler, if it will come, it may be optional or P Version only.
Hopefully an expensive one, I could save some money by unselecting.

 

[AnxietyRanger]

Indeed, judging by the front with no cross beam between A pillars, glass as much as possible seems the name of the game here. Of course one limiting factor on the "panorama" are the falcon wings, due to which I expect the second row to have only fairly minimal and static skylights, worse than Model S, but first and third rows (necks) should bask/bathe/burn in plenty of light with very high front and rear glasses and crossbeams only around the falcon wings/middle of the car.

Thinking of the possibly two-part rear window, it was suggested some time ago that lower drag over glass could be a reason to make the rear spoiler area from glass. That doesn't necessarily mean it will move. One reason to make it from a separate glass piece could be, say, crash safety. Build it so that in a rear collision the glass spoiler area (which reaches very far back) is pushed over the rear glass, instead of forcing all that energy immediately on the rear glass. It might also make sense from some other manufacturing point of view to have a separate glass piece for the spoiler area, even if it were static.

We don't know what this area does, if anything, but so far to me it seems the mule(s) may have a separate top part for the rear spoiler area, separate from the rear window and the rest of the trunk hatch.

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Thinking of that spoiler, if it will come, it may be optional or P Version only.
Hopefully an expensive one, I could save some money by unselecting.

Spoiler only for Performance model sounds plausible. Assuming, as we know of course, if there even is a spoiler.

 

[Gerasimental]

From all last pictures and conclusions, is one handwriting to find everywhere.

Tesla is trying to give the passengers the most panoramic 360 view possible.

Glass all over and trying to maximize this glass parts, by reducing all kinds of pillars or trim.

Been saying this since the first mule sighting. Can't wait to sit in one and experience it.

 

[Gerasimental]

Thinking of the possibly two-part rear window, it was suggested some time ago that lower drag over glass could be a reason to make the rear spoiler area from glass. That doesn't necessarily mean it will move. One reason to make it from a separate glass piece could be, say, crash safety. Build it so that in a rear collision the glass spoiler area (which reaches very far back) is pushed over the rear glass, instead of forcing all that energy immediately on the rear glass. It might also make sense from some other manufacturing point of view to have a separate glass piece for the spoiler area, even if it were static.

So, I'm terrible at explaining, but take my word for this: The effect of the surface roughness of that little section of glass has effectively zero effect on skin friction drag. That said, skin friction drag is only a minor contributor to drag compared to form drag. Form drag might even be reduced by having some roughness near the back as this would cause turbulent flow which won't separate from the surface and will re-attach more quickly to flow coming from below the car out of the rear diffuser.

Vandacca unfortunately got the golf-ball analogy wrong as it has nothing to do with reducing skin drag by introduction pockets of 'less sticky' air. The dimples cause the flow over the ball to be turbulent, meaning that the particles move in all direction with an AVERAGE speed going in the direction of the flow. Forces are transmitted by the inertia of individual particles as they bump into each other. Turbulent flow can pass over a surface at a much higher speed than laminar flow (all particles travelling in the same direction, forces between them are transmitted by 'friction' between particles moving at different speeds) without separating from that surface. The later flow separation results in a smaller wake, i.e. a smaller low-pressure zone behind the ball, which ultimately results in lower form drag.

 

[vandacca]

The effect of the surface roughness of that little section of glass has effectively zero effect on skin friction drag. That said, skin friction drag is only a minor contributor to drag compared to form drag. Form drag might even be reduced by having some roughness near the back as this would cause turbulent flow which won't separate from the surface and will re-attach more quickly to flow coming from below the car out of the rear diffuser.

Vandacca unfortunately got the golf-ball analogy wrong as it has nothing to do with reducing skin drag by introduction pockets of 'less sticky' air. The dimples cause the flow over the ball to be turbulent, meaning that the particles move in all direction with an AVERAGE speed going in the direction of the flow. Forces are transmitted by the inertia of individual particles as they bump into each other. Turbulent flow can pass over a surface at a much higher speed than laminar flow (all particles travelling in the same direction, forces between them are transmitted by 'friction' between particles moving at different speeds) without separating from that surface. The later flow separation results in a smaller wake, i.e. a smaller low-pressure zone behind the ball, which ultimately results in lower form drag.

Thanks for the explanation/correction.

 

[AnxietyRanger]

Gerasimental:

Fair enough on the drag point, you'll certainly get no argument from me - and interesting stuff in any case. Took a moment to digest, but interesting! One thing is sure, we need that wooden exterior paneling to be non-laminated then.

Tesla's reasons for using glass in that area might be pure aesthetical, too...

Anyhoo, what do you think Gerasimental, any point in having or need to have, an auto-raising spoiler, in the Model X from this point of view?

 

[Gerasimental]

Gerasimental:

Fair enough on the drag point, you'll certainly get no argument from me - and interesting stuff in any case. Took a moment to digest, but interesting! One thing is sure, we need that wooden exterior paneling to be non-laminated then.

Tesla's reasons for using glass in that area might be pure aesthetical, too...

Anyhoo, what do you think Gerasimental, any point in having or need to have, an auto-raising spoiler, in the Model X from this point of view?

Re spoilers: My purely intuitive answer is that if Model S doesn't need a spoiler, then Model X certainly won't need a spoiler.
Will X be faster than S? Probably not.
Will X be lighter than S? Definitely not.
Will X have a higher Lift Coefficient than S (i.e. generate more lift force due to aerodynamics at a given speed)? Honestly can't say and I don't think it will, but it's possible.

As I said, my intuition says no spoiler required, but the numbers might just come out such that it is.
In any case I think it would be a lot better if the car didn't need or have a spoiler. If it can be designed to run well at high speeds without a spoiler, then thats a much better outcome as it allows to save cost and complexity (think about what you need for an automatic spoiler: Sensors, actuators, seals, expensive materials, wiring, hinges, joints etc.), while saving bulk on the rear hatch (the spoiler and all the machinery controlling it have to go somewhere when they're not extended).

 

[AnxietyRanger]

Re spoilers: My purely intuitive answer is that if Model S doesn't need a spoiler, then Model X certainly won't need a spoiler.
Will X be faster than S? Probably not.
Will X be lighter than S? Definitely not.
Will X have a higher Lift Coefficient than S (i.e. generate more lift force due to aerodynamics at a given speed)? Honestly can't say and I don't think it will, but it's possible.

As I said, my intuition says no spoiler required, but the numbers might just come out such that it is.
In any case I think it would be a lot better if the car didn't need or have a spoiler. If it can be designed to run well at high speeds without a spoiler, then thats a much better outcome as it allows to save cost and complexity (think about what you need for an automatic spoiler: Sensors, actuators, seals, expensive materials, wiring, hinges, joints etc.), while saving bulk on the rear hatch (the spoiler and all the machinery controlling it have to go somewhere when they're not extended).

I agree (I expect) X won't be faster or lighter than S.

You are probably a far better expert than myself on aerodynamics, and balancing drag and lift, so this is merely someone talking who has been observing (mainly German) cars for a while. When I think of the cars that have spoilers, let alone automated spoilers, they seem to have one thing in common - far back reaching back windows or other downwards sloping rear designs, often very round shapes and, of course, they are fast premium vehicles. German SUV's too usually have spoilers, they are just at the top of the rear window (and of course are fixed).

Model S leaves quite a bit of space between the rear edge and rear window, and most importantly that space is used for a natural spoiler (not talking of the carbon addendum), unlike some cars that have automated spoilers like the Panamera and Audi A7 (or even the 4 Series GT) where there isn't as much in terms of a slope back upwards after the rear window. In these cars the slope back up is created with an emerging spoiler when needed. We recall the original, very round Audi TT kept crashing until they added a rear spoiler. Now, on Model X Tesla has certainly done its best to keep the car round and streamlined while increase rear space for second and third rows. We can see it has become higher (side windows are higher) than the 2012-2013 prototype(s) and the rear window extends further back than on a Model S, with less of a natural curvature back upwards because there is less space for it.

Is a car that drives fast, perhaps is high and round, but doesn't have much in terms of natural "take-off ramp" on the rear more in need of a spoiler, than a car with a natural slope up there, and perhaps a lower riding car...? If so, I could see why Model X would be more in this need than Model S. What do you think?

 

[Gerasimental]

I agree (I expect) X won't be faster or lighter than S.

You are probably a far better expert than myself on aerodynamics, and balancing drag and lift, so this is merely someone talking who has been observing (mainly German) cars for a while. When I think of the cars that have spoilers, let alone automated spoilers, they seem to have one thing in common - far back reaching back windows or other downwards sloping rear designs, often very round shapes and, of course, they are fast premium vehicles. German SUV's too usually have spoilers, they are just at the top of the rear window (and of course are fixed).

Model S leaves quite a bit of space between the rear edge and rear window, and most importantly that space is used for a natural spoiler (not talking of the carbon addendum), unlike some cars that have automated spoilers like the Panamera and Audi A7 (or even the 4 Series GT) where there isn't as much in terms of a slope back upwards after the rear window. In these cars the slope back up is created with an emerging spoiler when needed. We recall the original, very round Audi TT kept crashing until they added a rear spoiler. Now, on Model X Tesla has certainly done its best to keep the car round and streamlined while increase rear space for second and third rows. We can see it has become higher (side windows are higher) than the 2012-2013 prototype(s) and the rear window extends further back than on a Model S, with less of a natural curvature back upwards because there is less space for it.

Is a car that drives fast, perhaps is high and round, but doesn't have much in terms of natural "take-off ramp" on the rear more in need of a spoiler, than a car with a natural slope up there, and perhaps a lower riding car...? If so, I could see why Model X would be more in this need than Model S. What do you think?

I'm no expert honestly, I'm just finishing my masters in engineering and have covered a fair bit of aero over the years, but have next to no real world experience in applying it.
Good observation on the shape of rears of cars with spoilers, and this does make aerodynamic sense as a gradually sloping, long, rear window acts as a diffuser and therefore generates lift (This Wikipedia article explains quite well how a diffuser at the bottom of a car generates downforce - the same principles apply, in reverse, to a sloping rear window, but the absence of the floor to constrict the flow means the effect is less pronounced). More lift -> more need for a spoiler.

I would argue that spoilers on most German SUVs are purely aesthetic additions. Notably, the BMW X6 M, which has a very similar shape to Model X, a top speed of 155mph (same as P85D) and weighs in the same ballpark, only has a small 'lip' on the rear rather than any kind of active, large spoiler. In addition, Model X's weight distribution is probably rear-heavier due to the distributed battery weight and absence of engine in the front, giving more contact force for the rear wheels.

To your last point, the answer is almost certainly yes. In theory. The change in direction of airflow (i.e. upwards acceleration) that occurs at the 'take-off ramp' must necessarily go hand in hand with a downward force on the car. However, this is where experience of such things is needed to be able to judge the extent of the contribution to downforce from this relatively small change in airflow.

I get the impression you really want there to be an active spoiler, but in all honestly, all-in-all, I'm afraid I can't see a very convincing engineering case for it.

Just for fun, I found a picture of a bog-standard low-speed wing profile from NACA and superimposed it on an early TT. Are we that surprise it's rear wheels and the road surface only had the loosest of acquaintances? :biggrin: (Note that the location of highest lift on a wing is at around 10% of its chord, i.e. near the thickest section of the wing)

 

[AnxietyRanger]

I'm no expert honestly, I'm just finishing my masters in engineering and have covered a fair bit of aero over the years, but have next to no real world experience in applying it.
Good observation on the shape of rears of cars with spoilers, and this does make aerodynamic sense as a gradually sloping, long, rear window acts as a diffuser and therefore generates lift (This Wikipedia article explains quite well how a diffuser at the bottom of a car generates downforce - the same principles apply, in reverse, to a sloping rear window, but the absence of the floor to constrict the flow means the effect is less pronounced). More lift -> more need for a spoiler.

I would argue that spoilers on most German SUVs are purely aesthetic additions. Notably, the BMW X6 M, which has a very similar shape to Model X, a top speed of 155mph (same as P85D) and weighs in the same ballpark, only has a small 'lip' on the rear rather than any kind of active, large spoiler. In addition, Model X's weight distribution is probably rear-heavier due to the distributed battery weight and absence of engine in the front, giving more contact force for the rear wheels.

To your last point, the answer is almost certainly yes. In theory. The change in direction of airflow (i.e. upwards acceleration) that occurs at the 'take-off ramp' must necessarily go hand in hand with a downward force on the car. However, this is where experience of such things is needed to be able to judge the extent of the contribution to downforce from this relatively small change in airflow.

I get the impression you really want there to be an active spoiler, but in all honestly, all-in-all, I'm afraid I can't see a very convincing engineering case for it.

Thank you for that insight, much appreciated.

Certainly some spoilers on many types of cars may be aesthetic additions. But as far as I know, BMW X6 M for example does add a spoiler compared to the regular setup. Sure, it is not very big, but then Model X could well do with a Model S carbon protrusion... but Tesla might want to forgo such protrusions for better looks or for better aero at lower speeds. I guess it could be possible. This, of course, is the speculative part.

As for wanting there to be an active spoiler, I don't know if I'd put it that way. What I want to do - at least here on TMC - is contribute analysis of the Model X. I would like to make sense of what we are seeing - and I still think there is something in the spoiler area of the Model X that might warrant our continued interest. It could be something other than a spoiler and that's OK too.

Just for fun, I found a picture of a bog-standard low-speed wing profile from NACA and superimposed it on an early TT. Are we that surprise it's rear wheels and the road surface only had the loosest of acquaintances? :biggrin: (Note that the location of highest lift on a wing is at around 10% of its chord, i.e. near the thickest section of the wing)

If it makes any difference: That photograph is not a very early Audi TT, though. That is a fairly new version that has an adaptive spoiler.

This is an original Audi TT - that added a fixed spoiler after several crashes where the rear left the road...

 

[Gerasimental]

Thank you for that insight, much appreciated.

Certainly some spoilers on many types of cars may be aesthetic additions. But as far as I know, BMW X6 M for example does add a spoiler compared to the regular setup. Sure, it is not very big, but then Model X could well do with a Model S carbon protrusion... but Tesla might want to forgo such protrusions for better looks or for better aero at lower speeds. I guess it could be possible. This, of course, is the speculative part.

As for wanting there to be an active spoiler, I don't know if I'd put it that way. What I want to do - at least here on TMC - is contribute analysis of the Model X. I would like to make sense of what we are seeing - and I still think there is something in the spoiler area of the Model X that might warrant our continued interest. It could be something other than a spoiler and that's OK too.



If it makes any difference: That photograph is not a very early Audi TT, though. That is a fairly new version that has an adaptive spoiler.

This is an original Audi TT - that added a fixed spoiler after several crashes where the rear left the road...

You're right, of course. That's a 2nd gen TT, my mistake. The point still holds, as it had essentially the same profile and had a spoiler that extended automatically at high speeds, and would likely have gone equally airborne without this spoiler.
The reason I can't see Tesla forgoing a practical, small permanent spoiler in favour of an extendable automatic one is that it adds so much extra cost and complexity for what, looks? Not convinced. Aerodynamics are not terribly relevant at low speeds, at least not such that a small permanent spoiler on a with a car weighing over 2 tonnes will have any noticeable effect on efficiency.
I won't deny that the tape on the back of the mules looked indicative of something, but it may have just been hiding the glass going all the way to the very back of the car. Note the most recent mule, on page #22 of the sightings thread doesn't have the tape and appears to have a rear window with glass extending right to the back.
My opinion continues to be: no spoiler.

 

[AnxietyRanger]

The reason I can't see Tesla forgoing a practical, small permanent spoiler in favour of an extendable automatic one is that it adds so much extra cost and complexity for what, looks? Not convinced. Aerodynamics are not terribly relevant at low speeds, at least not such that a small permanent spoiler on a with a car weighing over 2 tonnes will have any noticeable effect on efficiency.

This, of course, is the part where things go beyond my expertise.

I won't deny that the tape on the back of the mules looked indicative of something, but it may have just been hiding the glass going all the way to the very back of the car. Note the most recent mule, on page #22 of the sightings thread doesn't have the tape and appears to have a rear window with glass extending right to the back.
My opinion continues to be: no spoiler.

I don't think this, from that page #22, is anything more than the car below shot below from another angle:

Then there are all these to consider:

Now, I'll grant you the latest mule shots almost seem to hide this spoiler area into one big rear window - but there is still enough there that makes me suspect it is two separate parts:

And we can see the top of the rear glass is new too, so something happened to the whole that could still have hidden the secondary part:

Now, having two separate parts there doesn't mean it necessarily is an adaptive spoiler, of course. Nor do we know if this mule work means anything for the production version.

 

[AnxietyRanger]

AnxietyRanger, I think you're really losing it. "active" rear window??? Your imagination is getting the better of you. That is clearly a single piece of glass (with no discernable seam). There is nothing "active" about that rear window.

The latest mule video proves the rear window is not a single piece of glass, but two pieces... That said, we don't know what that means, it could be two static pieces or there could be an active feature...

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Another view from the Sightings thread - definitely something protruding in the rear spoiler area. Now, it could just be a fixed piece of glass of course.