Originally Posted by bmorgan
This has been suggested before in another thread on this subject. I will re-itterate what I have said before. In my case, I do not use my trunk. It is a weekend driver, and the couple of occasions that I have opened the trunk, it was closed gently. I have never used the car for shopping, long trips, or anything that would require storing anything in the trunk. I think the only thing that has ever been in my trunk was a racing helmet.
While this seems like a logical reason for the cracking, I can assure you that is not the cause in my case. I really believe that it is a design flaw in the roadster wings.
Whatever causes it for all of us who have experienced it, I totally agree it is a design flaw where the designers did not take into consideration some common forces that end up being applied to the wing. I didn't mean to imply otherwise, nor was I accusing anyone of slamming their trunk.
I was just suggesting that slamming the trunk too hard (by anyone - a previous owner, a service person, etc.) seems like it would be a very common (and easy) way to exploit the flaw. Maybe hitting a really hard bump is too. While I agree that there must be some downforce at very high speed (but little at low speed - the downforce of a wing varies with the square of the velocity), not everyone with cracked wing mounts drives their roadsters 150 mph, so it just seems to me that high speed wouldn't be the most common way to exploit the flaw.
However, when you drop something, even from only four or five feet, the deceleration forces when it hits the ground can be very extreme. Add to that throwing something at the ground (or throwing a trunk lid shut), and you can see where I'm coming from. Laptop hard drives designed to withstand a short fall are typically rated at hundreds (or thousands) of g's (It's not that fall that kills you - it's the sudden stop at the end). The trunk swings very easily around the trunk hinge pivot point on the roadsters, and wing is out at the end of that swing, and the wing's downward force has more leverage on the mounts on the roadster when it suddenly stops than on the coupe, because the mounts are longer.
The mounts should have been made stronger, since many are cracking, whatever is exploiting the design flaw for each of us who have experienced it.
There is probably a g-force measuring app for an iPhone - one could tape the phone to the trunk lid, then...
