More Pickup truck Aero

[Otto]

Got aluminum or fiberglass dome tent poles? (the type that bend to keep the dome tent fabric taught)

If so, you could use them or perhaps PVC plastic pipe to make longerons that go from the upper back of the cab to mate with the upper edge of the tailgate, then stretch the plastic over that. This would retain shape and prevent the concave section at the rear.

[bennelson]

I was actually thinking that tent poles might work pretty well for something like this.

In the long run, I will be doing a rigid cover, to better protect my tools and work equipment I have to carry around at times.

Seems like an "aero-tonneau" is simple enough that I am suprised there aren't any commercially available yet!

[Otto]

Google for "aircraft turtledeck" and look for info on fabric-covered planes. A turtledeck is the fairing behind the pilot's head on old biplanes, etc., and is an elongated shape to streamline the flow. Same story would work well with your pickup truck: Fabric stretched over stringers into aero shape, with stringers runing parallel to the long axis of the vehicle.

Dacron is used extensively in homebuilt planes, comes in a slew of colors, and is heat-shrinkable to make it nice and tight over a lightweight frame, such as made of fiberglass, aluminum, wood, or even PVC pipe tubing. Once you have the shape right, you can add dope, epoxy, etc. to waterproof it, same as done on aircraft.

This would be an inexpensive, light, yet strong and translucent aero mod for your truck. You could hinge it at the upper rear edge of the cab roof, then add gas struts (as used in hatchbacks or hoods) or a stick to hold it up when you're getting stuff in and out of the cargo bed.

If Dacron is not strong enough, consider the stuff used on folding kayaks and baidarkas, whose structure is essentially as described above. Clear Mylar may be another option--it's been used to skin ultralight aircraft for decades, and makes them almost transparent.

Keep us posted.

PS: This thing will generate some lift, so take that into account. I've considered making a cockpit cover (replacement for Bimini) for my speedboat this way, as the lift would help pull the boat a bit higher in the water at speed, reducing wetted area and therefore drag. Never got around to it, though.

[kevlar]

Here's what I ended up using. So far, two weeks at 80 mph plus intervals, seems to hold up. If I had planned better, it would have been arched upward. Thia may work well with your clear plastic too.

[kevlar]

Also, let me know if you come up with a good way to snap/unsnap it in. I have mine held with rigid pipe straps and self drilling screws....

[bennelson]

Maybe you could cross one of those pipe clamps with a c-clamp to make a device you can clamp the pvc directly to the frame, yet still be easily removable.

[kevlar]

I'm liking that... sounds like a weekend and beer!