Headwind effect yesterday

[sotek2345]

I hope there isn't too much wind inside the truck.... . That could get ugly.
Seriously though, we have them for boats. Apparent wind direction and speed on the moving vessel minus the direction and speed of the vessel gives you true wind direction and speed. You would need an instrument (anemometer) that could handle Lightning speeds.

They have them on airplanes, so I don't think the speed is the issue .

That said, it really isn't worth adding hardware. Even something as inexact as using local weather data would be helpful.

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[Adventureboy]

They have them on airplanes, so I don't think the speed is the issue .

That said, it really isn't worth adding hardware. Even something as inexact as using local weather data would be helpful.

Yes, slightly different dynamics but similar results. Pitot tubes on aircraft measure the airspeed - that's easy enough to handle the speed part but it would have to be on a wind vane on a ground-based vehicle and high enough to get out of the turbulence created by the vehicle. In a sailboat, it is at the top of the mast to get out of any turbulence. In an airplane, true wind direction is calculated by the differential in speed/direction through the air minus the speed/direction over the ground but an airplane is already a big wind vane and only travels with the air flowing straight from nose to tail. . In any case, it is more difficult in a ground-based vehicle and would probably look kinda funny with a wind vane on a pole out the top of the truck. Somebody will probably do it though now that we've planted the seed...

 

[hturnerfamily]

Headwinds, or even sometimes SIDE winds, are your enemy. Plan accordingly.

10 mph headwinds means 10 mph 'slower' driving to offset the difference, if you feel you must maintain RANGE rather than speed to your destination.

The more 'headwinds', the slower you go to make up the difference. Oh well.

 

[GuyInVA]

Has appeared here before, related to improving aerodynamics:
https://www.mivehiclesolutions.com/products/aero-x-f-150

edited: word

 

[flyct]

Yes, slightly different dynamics but similar results. Pitot tubes on aircraft measure the airspeed - that's easy enough to handle the speed part but it would have to be on a wind vane on a ground-based vehicle and high enough to get out of the turbulence created by the vehicle. In a sailboat, it is at the top of the mast to get out of any turbulence. In an airplane, true wind direction is calculated by the differential in speed/direction through the air minus the speed/direction over the ground but an airplane is already a big wind vane and only travels with the air flowing straight from nose to tail. . In any case, it is more difficult in a ground-based vehicle and would probably look kinda funny with a wind vane on a pole out the top of the truck. Somebody will probably do it though now that we've planted the seed...

in an airplane and boat you have a need to know wind speed and direction to maintain ground track by compensating for drift angle. In a car the only effect on the car is the headwind/tailwind vector.

This is bringing up old memories of life before digital calculators and computers. As an engineering student almost 60 years ago I remember my trusty slide rule. When I was learning to fly planes 55years ago I used a similar complicated slide rule type device called an E6B.

 

[Adventureboy]

in an airplane and boat you have a need to know wind speed and direction to maintain ground track by compensating for drift angle. In a car the only effect on the car is the headwind/tailwind vector.

This is bringing up old memories of life before digital calculators and computers. As an engineering student almost 60 years ago I remember my trusty slide rule. When I was learning to fly planes 55years ago I used a similar complicated slide rule type device called an E6B.

This one?

You still fly?
Side wind components will still introduce additional drag as it catches things like wheel wells and other non-streamlined items on the side of the truck. Agree the headwind component is the most significant and a simple headwind airspeed device would improve the GOM tremendously during the windy winter weather. Maybe Ford will install a Pitot tube on the T3s.

 

[Henry Ford]

This is bringing up old memories of life before digital calculators and computers. As an engineering student almost 60 years ago I remember my trusty slide rule. When I was learning to fly planes 55years ago I used a similar complicated slide rule type device called an E6B.

Holy moly! I doubt they even teach students how to use E6Bs today. When I started flying I bought a fancy electronic calculator because the E6B was intimidating. I eventually switched to the E6B because it was easier to use. Today both methods are obsolete because flight planning software is so sophisticated and even GA airplanes have instantaneous fuel predictions as well as wind and groundspeed that is probably displayed on a screen that is always visible. There are rarely surprises.

On the other hand, you might be well into a trip in your Lightning before you realize you aren't getting the mpkWh you thought you would. If you make an adjustment it is never really clear what your current mpkWh or range is. I'd like to see an instantaneous mpkWh and range display option. It would allow pretty much anyone to see how change in speed affects real time efficiently.

 

[flyct]

Holy moly! I doubt they even teach students how to use E6Bs today. When I started flying I bought a fancy electronic calculator because the E6B was intimidating. I eventually switched to the E6B because it was easier to use. Today both methods are obsolete because flight planning software is so sophisticated and even GA airplanes have instantaneous fuel predictions as well as wind and groundspeed that is probably displayed on a screen that is always visible. There are rarely surprises.

Sorry for the off topic.

Things change... I worked on B-52's H-Model with Nukes back in the days when Doppler Radar had Vacuum tubes. The Doppler radar calculated Ground speed, and drift angle. That was used to calculate wind speed and direction for the Bomb Nav systems. Wind Speed and direction was critical for gravity bomb drops accuracy.

Who would have thought that TODAY the same 50+ year old B-52H's are flying and are being retrofitted with new avionics and engines. https://www.aviationpros.com/aircra...begins-first-us-air-force-b-52-radar-upgrades

On the other hand, you might be well into a trip in your Lightning before you realize you aren't getting the mpkWh you thought you would. If you make an adjustment it is never really clear what your current mpkWh or range is. I'd like to see an instantaneous mpkWh and range display option. It would allow pretty much anyone to see how change in speed affects real time efficiently.

Agreed. While I only have a few months experience with my Lightning I find that the Lightning range estimate is not as accurate as my Tesla is. An instantaneous mi/kWh indication and range display would be nice. Even a current % battery remaining and a % at destination at current efficiency would be nice. Tesla does a better job with that.

 

[flyct]

You still fly?

Sold last plane about 5 years ago. You have to know when to quit.

 

[invertedspear]

I'd like to see an instantaneous mpkWh and range display option.

I think "instantaneous" would vary to the point of uselessness. You need at least a little averaging over time. Just reset one of your trips in the power consumption app. Give it a couple minutes and you should have something of decent enough accuracy to make a calculation off of.

 

[RickLightning]

We drive a 125 mile trip between our cabin and house about 3-4 times per month. This trip normally uses 45% of our battery capacity. Yesterday we had an average of probably 20-25 mph headwinds and we used 60% of battery capacity with our ER Lightning. That‘s a whopping 33% increase in energy consumption.

I was very surprised at the amount of range hit it took with the wind effect. This truck (and all trucks) severely suffers from parasitic drag due to the lack of aerodynamic design.

The key here is to understand that the 20mph headwind meant you were driving 90 instead of 70mph.

In October we took our Mach-E on a 10 state, 8 national park trip. In New Mexico or Arizona, we hit a tremendous headwind. All the trucks slowed down. Our AVERAGE efficiency dropped from 2.7 to 2.1. That's a roughly 22.3% hit! We have had a Mach-E for 2.5 years. We have driven North to South many times both ways. I have NEVER experienced a hit like this before, assume our prior winds were more sideways. It was very eye opening as we made the hotel parking lot with 6 miles of range left...

 

[Henry Ford]

I think "instantaneous" would vary to the point of uselessness. You need at least a little averaging over time. Just reset one of your trips in the power consumption app. Give it a couple minutes and you should have something of decent enough accuracy to make a calculation off of.

Fair. "Instantaneous" might be the wrong word but something calibrated to a short enough time frame so you could see the affect of changing speed or conditions. I don't know if that's thirty seconds or two minutes but it seems like that would be useful information and relatively easy to implement.

 

[TheWoo]

I'd like to see an instantaneous mpkWh and range display option. It would allow pretty much anyone to see how change in speed affects real time efficiently.

I think Rivian has a "Last 15 Minutes" efficiency number on the display. I would love something like that.

 

[RichB-HTX]

Realtime mpkWh would be a whole lot simpler and could be done with a software update. We already have a brake coach, how about a highway coach?

I’d love to have instantaneous m/kwh so I can see the sweet spot on trips when I’m willing to sacrifice speed for range. It seems they have all the info to do this.

 

[Zprime29]

Drove Tucson to El Paso on Dec 23. There was a 10-15 mph tail wind most of the drive. I had cruise at 75 and still got 2.2 mpk despite the 1500ft elevation gain. It was amazing. Really hope I don't have that headwind going back next week.

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