A car in the supermarket carpark
 

The more I looked, the more fascinated I became.

https://www.youtube.com/watch?v=pvLkQRsNLF4

In another thread I asked about modding the hatch on a Geo Metro, and this is exactly on point, so thank you.

• The lip: better, worse or an evolution of the Gurney flap?
• The fences: an area of re-attachment after the roof rack hardware?
• The green arrow: Was that a step or a slot beneath the arrowhead?

1. I don't understand the reference to a Gurney flap. A Gurney flap is used on a wing. This is not a wing, so I cannot see how anything on this spoiler can be referred to in that context. Re the lip, 'better' or 'worse' in what regard? Lift? Drag?

2. The longitudinal strakes, I suggest, perform the function I ascribed to them in the video. I don't see the longitudinal filler strips doing much to cause separation.

3. Step not slot. And such a small step it would be of no consequence I would think.

1. Can you propose a word to describe a small scale disruptor to modulate the flow around a larger feature? 'Gurney flap' wasn't named for an airplane pilot.

2. I though it was a weak point due to the average 7° crosswind.

3. Okay. I suspect it's a manufacturing issue, avoiding trying to fit to the hatch edge.

1. Spoiler lip

2. Where did you get that figure from? That's much higher than any data I have seen.

3. Yes I think so - need a minimum thickness in the moulding.

Don't know. A recent thread. Google's search function is no help — Six pages on 'crosswind yaw' and no way to sort by date. And it hits on UTF-8 when I search on '7° crosswind'! I'm pretty sure you were in the thread.

A DuckDuckGo inurl: search find one hit, no numbers.

I'd care more, but it's sunny outside.

The median yaw that Nissan found for the US was 4 degrees.

I found it. It was in a reference hearsay by you-know-who.

ecomodder.com/forum/showthread.php/hidden-real-drag-coefficient-39010.html#post640594

7 degrees (what you said) does not equal 7 mph (what Aerohead said).

You're right, of course. It was in imperfect recollection. Hopefully the cite will appear.

rear wing feature
 

The only thing I can make of it is, that those leading structures are hiding a particular type of hinge which allows the hatch to clear the roof when it's raised, rather than be immediately broken off, or jam.

I could see an external hinge, but they went out of style in the 1950s.

Wrong again!

https://s1.cdn.autoevolution.com/ima...age-4571_7.jpg

wrong again
 

From the perspective of your photograph, it appears that those structures would have either penetrated the roof or broken off.
I don't have the car to examine.
I've had to confront clearance issues like this with my own projects.
Civility is nice too!

Did you click on the photo and enlarge it? Look at the shape of the inner skin? It shows no such projections.

enlarge
 

The light-green car with its hatch open?
I never saw anything in the video which helped explain the hinge.
If the light-green car has the same rear spoiler as the original image, I don't see how the hatch could possibly open without interference.

A recessed hinge has the edge move outward and forward. This is really a minor detail compared to it's function.

I found a Jetta deck-lid spoiler that is the right width and curvature to match up to the Metro. All it needs is sail panels. I'll take a pic.

As it happens, today I saw a Mirage without its spoiler! And it had those two little forward bumps in the roof (note: not the side ones that I talked about in the video).

So yes, maybe the forward bumps are for the hinges (even though it doesn't look like that from the inside view).

So in this case I was too quick to dismiss your point, and I apologise for that.

You might find these photos useful .

Gurney flap only applies to Wings ok ,what is the proper technical term to describe a gurney flap shaped protrusion on a Leading Edge attached wing AKA spoiler?
Why does the rule book for Bonneville ,El Mirage, ect LSR say that Granny flaps are allowed on a Bonneville spoiler, the same rule specifies that the Leading Edge of the wing be attached therefore it is a spoiler with an allowed Gurny Flap? I don't know of a more technical writing than a rulebook for racing.


Southern California timing Association 2019 rules and Records , Rule # 4.CC.8 pg60 , 1 , "Gurney flaps are allowed but cannot extend above or behind the spill plates" (2"aft or 8"above)

Anything above or below a wing is called a fence generically. Flaps are hinged things that deploy to alter airflow.

See also: Starship.

blind in one eye, couldn't see out of other
 

Parked next to a Mirage last Sunday. Obviously, the actual rear hatch gap was clearly in the original photograph. My brain, somehow couldn't accept the fact that this gap could be so far ahead of the trailing edge, and dismissed it.
Apologize for confusion and Armadillo-vision. :o

Sorry, Wikipedia disagrees , wing fences are perpendicular to Gurney flaps , and developed for use on swept-wing aircraft that suffer from full span stall. Basically a full cord Vortex Generator.
Gurney flaps sole purpose is to give a simple basic flatish/concave shape a more complex convex curved air flow/ boundry layer pattern without the complexity

Wing fence =

Wickerbill = trim tab on full lock.

Dan Gurney also invented the Gurney Bubble.

https://www.thetruthaboutcars.com/wp...ey-550x309.jpg
www.thetruthaboutcars.com/2014/11/gurney-bubble-gurneys-bubbly/

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It's interesting, in light of recent controversy, That this comment highlights that the squareback 'bread-van' body killed Ken Miles. The solution was a fastback. :confused: