LightShip Systems Review - Aerodynamic Enhancement System

[Rory (Lightship Team)]

Any available info (or informed estimates) on how the drag of the Lightship compares to Bowlus trailers?

www.bowlus.com

Hi Josh - curious the feedback of others with real world experience. @turbopilot ? I can reach out to a contact I have who is considering a swap to a Lightship.

From our engineering teams here, the key differentiating features:
- blunt shape at front of bowlus is not as good at reattaching the air coming off the tow vehicle (compared to tapered like lightship)
- frontal area is much bigger than lightship
- camm tail shape (lightship) is better than wedge to detach air cleanly

we have some estimates here internally at the difference in drag, but wouldn't want to share those publicly as not validated/proven.

 

[turbopilot]

Hi Josh - curious the feedback of others with real world experience. @turbopilot ?

I have no experience with the Bowlus. But given LightShip has a very refined force sensor (on the hitch of the LightShip) and associated hardware/software, there is no reason a "Portable Force Sensor" could not be easily fabricated and placed between the tow vehicle and any brand of trailer for a tow test. The force sensor can read the force necessary to pull the trailer (in Newtons). Once you have the force required to pull the trailer you can back into the hardest number to calculate without a wind tunnel: the Coefficient of Drag.

So there is no reason LightShip could not easily calculate the Coefficient of Drag for every make and model towable RV on the market with very little effort. Could even offer a service to anyone with some other brand of towable to come to the factory and get your Coefficient of Drag measured (along with a sales pitch )

The drag equation is simple to calculate once you know the Coefficient of Drag for a trailer.

The drag force (F_d) is calculated using the standard aerodynamic drag equation:F_d = ½ × ρ × v² × C_d × AWhere:

• ρ = air density
• v = velocity
• C_d = coefficient of drag
• A = frontal area

I also think it would make sense to display the real time force measurements from the force sensor on the LightShip in tow on the Atlas tablet. There are so many variables impacting drag force (speed, wind, cross wind angle, temperature, altitude, tire pressure, rain, snow etc), displaying the force actually experienced in real time, at the hitch, towing a LightShip would be valuable information for the driver because that directly impacts range.

 

[Holdmybeer]

In conclusion Gemini AI's verdict is the Lighship totally wins on total drag force at hwy speeds because its lower frontal area displaces less air at hwy speeds.
However, the Bowlus likely has a lower pure drag coefficient because its permanent fixed shape is more purely raindrop and lacks the mechanical seams of a telescoping roof. Furthermore, the boat tail design of the Bowlus is more aggressive than the tail design of the Lightship at minimizing drag at hwy speeds
* Lighship's stated goal was to achieve a drag coefficient comparable to a Tesla model 3 which is ~0.23, however this is an aspirational benchmark rather than a confirmed figure for the trailer itself.