[slowmover]

In the above pair of posts I realize I've gotten pretty far from the title of this thread. It is that I note that, for general purposes, the "thinking" about fuel economy in re travel trailers is that light weight and small size are seen as fundamental.

But the numbers are otherwise.

A turbodiesel tow vehicle and aerodynamic travel trailer (where ALL edges are radused) is the winner. Lighter weight due to materials AS WELL AS low center of gravity are also what matter, but true aero is king.

We can find dozens if not hundreds of examples where a small gasser pickup and pseudo aero trailer fail. And fail in space utilization primarily, fuel economy secondarily. What good is 15-mpg with cramped accommodations for four where the mpg is the same for six with room to spare in a far larger rig? With better on-road stability? And higher solo mpg. And that one can carry more gear for weather or hobbies as well as the ability to stay put longer once parked. Etc.

Six people is a far cry from just two. The economics of RV travel are far more than fuel cost, the other big expense is ground rent. Ten nights of full hookups at $45/night = $450. Over a month if one can cut this to four nights the savings is $270. At 16/mpg (as on mine) the distance covered at $4/gl diesel is 1,000-miles. So, how long I can park "free" on BLM land, for instance, is directly related to the trailers capacity for water, waste, food and propane.

The longer one can stay in one place without external inputs of any sort is a larger context than worrying over fuel cost (and then compounding that problem with years of time and effort).

One can play with this sort of thing quite a while. There are those who in retirement move once monthly versus once weekly to keep expenses down. $3000/monthlly is something of a bottom figure for RV travel. Those who say they can do it cheaper usually leave out considerable areas of concern (tent travellers, for example). There is a subsidization by the tow vehicle in that (very high relative miles). And lack of all weather shelter. It is possible, after all, to be sick or injured. Insects, vermin, the damp, etc, are all contraindicated in such (general purpose, in my view).

There is a ratio to be explored, here, would be the point. My starting point is two weeks of full independence as a goal for least expensive travel. Choosing where I park in order to minimize ground rent is just as important as fuel economy.

And that an RV so spec'd is also shelter for ones family when the lights go out back home. Expand the usefulness beyond being just the infrequent vacation (seen over a decade).

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