[Golden Ears]

@redpoint5 this might be the most egregious thread derailing I have ever witnessed.

Slowmover was banned instead of you? If I was a mod I’d ban those who contribute the least to solving problems.

Ok let’s get to the meat of this.

The real issue here as we all recognize it is efficiency of towing by improving the aerodynamic relationship of the tow Vechiles and trailer.

It has absolutely zero to do with whether the tow vehicle is powered by gasoline, diesel, cow farts, hydrogen, electricity ,hybrid or your bunch of hot air blustering tomfoolery. Oh you’ll all hate me now. But maybe you’ll stay focused by channeling this into the original discussion.

Solve the aerodynamic relationship or coupling relation of trailer to tow vehicle and every single person on the planet benefits from the efficiency (except the fuel sellers and makers of solar panels ) .

Most of the energy is translated to heat. Better aero means less waste heat per mile no matter the energy used.

So here’s a personal experience .

In 1993 I won a silver medal for downhill speed skateboarding from the French & Spanish Olympic committees in adventure games held in the Pyrenees mountains. Without improving my own aerodynamics by wearing a rented wetsuit, I might’ve placed third or worse.

Gravity is a great equalizer when it comes to gravity powered vehicles.

So let’s talk a little bit about aerodynamics with skateboards. I am also the world longboard champion.

Here are some different speeds attained on the same hill using the same gear, but with different configurations. The hill is the Harvard’s Arnold Arboretum in Jamaica Plain near Boston. A spiral hill of mild grade.

Speeds attained: gear is consistent. 55” Gravity brand Ed Economy Longboards with 78a hyper rollo wheels. Speed at bottom of hill is in mph. Hill length is identical for all runs.

1. Standing upright turned sideways 19mph
2 . In a “ Hut Tuck” bent at waist , hiding one legs behind the other. 24 mph
3. Two boards , two people identical weight and build in Catamaran 27mph ( 4 legs hide in the frontal area of about 1.25 legs , torsos present the same frontal area as a person sideways standing…if the hill were faster the hut tuck might win if speeds exceeded 5-0 mph.)
4. Two boards , 4 people with a space between the front row catamaran and rear 2nd row. 32 mph
5. Same but all bunched up near the front , no gap 36mph
6. 6 people 3 rows , holy crapolla 53 mph ! We nearly destroyed the 8 wheels employing a reverse ski snowplow stop ( all leaning outwards legs locked)

So what’s interesting to learn here is as the frontal width becomes less significant relative to the length we have DRAMATICALLY faster speeds despite exponential drag increase.

12 legs hide in the frontal area of 1.25 legs.

Also interesting to note was the speed seemed ( totally subjective here) to pick up the most rapidly at speeds over 20mph. It’s was pretty insane . Mostly because I was the only skilled person in this directing 5 inexperienced people 2 of whom have never skateboarded and had to keep them calm when I was flipping out inside my head wondering if I could stop them before we ran the possibility of colliding with a random patrolling park ranger car around a blind curve breaking up to 12 legs at once.

So melding the gap here to me seems akin to what little I know about sailing and “ hull speed”. Apparently long thin boat hulls can hit a higher speed if their waterline length is long relative to their frontal area. My prom dates father owned “Circus Maximus” a long fast sailboat.

So if we want to solve this equation , I think what we need is a stretchable yet very firm relative to highway speeds …uhhh “Linking shrouded fairing” that connects the tow vehicle to the trailer front in an aero shape (Better than the bendy bus ridged accordion linkage )

I own a 2017 Model X 90d which already has a battery capacity of about 85.5 which maybe about 81kw (at 100% charge) is usable (4kW is hidden reserve ). It’s “Ideal range when new was 313m and now is 299m thanks to a tow yard letting the battery go dead. So let’s say I have 79kw available.

Now I need to tow an airstream or similar build tin can .

1.So I think the best I could manage is to put a sail type cord ridge in some stretchable sail type cloth …and slam that down under/inside the trunk lid hinge.

2. Take the other end and secure that to the airstream top stretching it over the roof with a slight bulge and then taper that back down to the roof line of the airstream.

3. Wrap under the trailer as well linking the underside of the car to the underside of the trailer.

4. Add some sort of taper to the airstream end or aero diffuser , maybe try to channel some air to fill in the turbulent end.

5. It might not all be stretch materials, some might have to be segmented almost like an armadillo to have enough range of rotation for turns.

6. The airstream has to loose all the crap HVAC vents antennas on the roof and smooth out the bottom. Go to a mini split, or just use a larger compressor/heat pump on the Model X and duct the air inside so trailer weight increase is marginal . Charge the entire trailer off Model X traction battery , but also have a similar battery arrangement in the trailer ..(I was thinking the entire Tesla battery and rear axles salvaged out of a red drive Tesla and plunking the trailer shell around that ) .

Now when you go off exploring in the tow car you can return and replenish the batteries in the trailer. If you hit a flat grade you could draw upon the trailer battery if needed for the flattest sections using an inclinometer switch and regen proportionally more than Model X on small,downhills to charge the trailer battery and not need thermal management of that battery , and save the Model X high output traction battery for high current hill climbs ( which might need battery thermal management ) and steep hill Regen (also higher current) . Trailer could also do Regen down hills to reduce trailer sway, as sway is increased if the trailer tries to go faster than the tow vehicle. In a typical configuration with model x and a trailer with trailer brake controller , slowing the trailer adds friction drag to model x and reduces Model x regen form the tow/trailers combo. If the trailer has regen set ever so slightly higher than Model x and this in cases slightly for steeper declines, this would make for a very safe and efficient recapture of energy and perhaps allow for slightly more safety margin for quicker descents.

Lastly, the trailer should have slight taper both in height going towards the rear and width . Not much is needed. I used to own (2) 1994 Mercedes E500 sedans (.01 worse than Tesla Model S, and a big part of that was taper and managed airflow. The w/124 chassis were the first aero Mercedes’ passenger cars…slippery bricks.

And the trailer should be able to shrink in height 9maybe not like the trail manor, but certainly shrink another way to be below the height of the roofline of Model x. And if not you will need that trailer “Bow bulb