Did I miss it or were temps, altitude and winds reported?
As I recall on the first run to Phoenix and Apache Junction the conditions were as follows;
No load except full fuel and the Mrs.
No dash or roof A/C used.
Ran as close to 56-57mph as I could maintain, no cruise.
We left at 4AM in the morning, about 80 degrees F.
Aviation winds forecast called for 2mph left quartering tailwind.
Tucson is 2389 ft elevation at TIA, Phoenix is 1124 ft at Sky Harbor.
Apache Junction elevation is listed at 1722 feet.
We went approx 100 miles north northwest to Phoenix on I-10, right and due east on hwy 60, 25.6 miles to Shell station in Apache Junction. I-10 and 60 are constantly up and down, up and down. Not a lot in elevation but enough to be a pain if you’re paying attention.
The first leg yielded 17.26 mpg. (!) 126.7 miles, 7.34 gallons.
The return leg two hours later, after having breakfast with my mom and sister, went like this;
Winds forecast was right on the hump between 4 and 7 mph, blowing south, southeast. For the Apache Junction to Phoenix leg (heading due west) it was a right quartering headwind, for the Phoenix to Tucson leg (south, southeast) it was all over the map, mostly an annoying left crosswind.
By then the air temp was right at 100 degrees and we used the A/C the entire trip back, same speed as first leg. Result for this leg was 14.65 mpg. 130.3 miles, 8.89 gallons. The extra 3.6 miles was driving to my mom’s house and back from where we filled it up. Come to think of it, the drive train was also cooling off for two hours as we had breakfast and visited with my mom and sister, which means getting back to the freeway the drive train was getting up to operating temperature.
For the second trip, conditions were as follows;
RV fully loaded with 30 gallons of water, full fuel, food, wine and provisions for 4 days in the mountains, and the Mrs. No toad, don’t have the hitch extended yet.
Winds forcast for first leg of the trip, which was identical to leg one of the first test above, was 4 mph tailwind (from the south).
We left at 5AM in the morning, temp about 85. Intended to not use the A/C but it was just too damn hot. Used the A/C just enough to keep us from dying, was on probably 50% of the time, 56 -57mph. Pain in the butt segment. Had to pull off the freeway about 2 miles to meet friends, stopped a second time halfway to Phoenix to tape the back door on my boat tail shut (had all my big light stuff back there), and worst of all had about 20 miles of 10 mph crawl stop and go when we got into rush hour traffic in Phoenix.
That leg yielded 16.65 mpg. 128.2 miles, 7.7 gallons. Not bad considering.
Sunday afternoon on the way back from the Mogollon Rim, we were able to get back to the same station in Apache Junction on the way back. Same pump, pointing same direction, you know the drill. The same return leg was forecast on Thurs morning for 8 mph, right quartering tail wind (south, southeast). How accurate that was I don’t know, forecasts change a lot in four days around here.
We were about 15 gallons of water and a litre or two of wine
and some food lighter.
I can tell you two things about the return segment. The tail wind was slightly stronger, and the cross winds were considerably stronger.
It was about 115 degrees in Apache Junction that day, we left the station at about 3:30 PM, and used the A/C all the way home. Results were 14.96 mpg. 126.6 miles, 8.46 gallons.
I believe the increase over the first return leg was due to the stronger tail wind but maybe the pans played a role in that too.
All I know is after achieving the gains with the boat tail, and spending three weeks on my back in a 100 plus degree shop with crap falling in my eyes, yes I was disappointed with not getting a no-brainer, hell yes it made a difference observation that I could attribute to the belly pans. Hopefully that will change with some more work.
This miniature novel is why I didn’t report all the details before, but there it is for people who want to read it. I’ll answer the other questions in another post so this one doesn’t go on forever.