New Bigfoots - Page 3 - Fiberglass RV


Reply
 
Thread Tools Search this Thread Display Modes
 
Old 02-02-2013, 10:30 PM   #29
Senior Member
 
Francesca Knowles's Avatar
 
Name: Francesca Knowles
Trailer: '78 Trillium 4500
Jefferson County, Washington State, U.S.A.
Posts: 4,543
Registry
Quote:
Originally Posted by ruscal View Post
Francesca,
They're both very significant, but come into play in different ways. Weight matters most while climbing, as it takes more fuel to lift weight up a hill. Wind resistance matters everywhere, and becomes more significant with speed. Hold a ping pong paddle out the window at 20MPH flat to the wind and see if you can feel it. Do it again at 120, and you may get hurt. We cyclists know all about the effects of wind resistance and energy use. It is very significant at almost any speed and the largest drag bicyclist will experience. Heavy bicyclists know all about how weight effects climbing hills.
Slow driving will affect MPG always. Heavy vehicles hurt climbing.
Russ
Bicycling aside:

I was speaking to "aerodynamic shape" alone, and specifically within the limited sphere of camping trailers and the average speeds they travel at.

For decision-making purposes, at least for me, there's not enough variation in shapes among trailers to make significant differences in fuel efficiency, especially over the relatively small distances most travel.

Surface area presented to the wind is of course another story...

Francesca
__________________

__________________
.................................
Propane Facts vs. Fiction:. Click here
Tow Limit Calculator: Click here
Francesca Knowles is offline   Reply With Quote
Old 02-03-2013, 01:36 AM   #30
Senior Member
 
Name: Russ
Trailer: Scamp 16' side dinette, Airstream Safari 19'
California
Posts: 588
Aerodynamic shape alone could be most of the difference between my Jeep Wranglers 14-15 mpg and my girlfriends Jeep Grand Cherokees 19-20mpg when they are driven on the freeway. They both have the 4.0 six and similar tire sizes. I don't know the weight difference, but the freeways are pretty level around here, so not a big factor. The Wrangler was designed to block as much wind as possible. (Flat bumpers, grille, windshield, fenders, etc. It is also flat on the trailing edge. The Cherokee is a 2000 model with rounded swoopy everything. The front grille is rounded and sloped back. The headlights are sloped and faired into the body. The windshield slopes back radically, and the trailing surfaces are rounded as well. The frontal area of both vehicles could be slightly different as I had no way to really measure them. The rear axle ratios were identical and they both have overdrive. When driving in town stop and go the Grandís mileage drops to about 16. The wranglers stays at 14-15. The shape has to be how the grand can achieve 33% better freeway economy. That is a pretty worthwhile difference unless you don't drive far enough to amass any real savings. The egg shape is a real advantage on fuel usage due to reduced frontal area and aerodynamics but eliminates some storage space inside a trailer.
Russ
__________________

__________________
ruscal is offline   Reply With Quote
Old 02-03-2013, 07:06 AM   #31
MC1
Senior Member
 
MC1's Avatar
 
Name: Wayne
Trailer: Nest fan, Airstream Sold
Ontario
Posts: 2,006
Shape or weight or the size or shape of the TV??
It can get complicated.

Our Nissan van towing a 2,000lb Coleman pop up got us 19MPG av.

The same van towing 4,500lb Airstream averaged 16MPG.

Here is an interesting article that relates.... Can-Am RV :: HH 38-1
__________________
MC1 is offline   Reply With Quote
Old 02-03-2013, 08:56 AM   #32
Senior Member
 
Name: Dave
Trailer: '78 Trillium 4500
British Columbia
Posts: 150
Quote:
Originally Posted by Francesca Knowles View Post
Bicycling aside:

I was speaking to "aerodynamic shape" alone, and specifically within the limited sphere of camping trailers and the average speeds they travel at.

For decision-making purposes, at least for me, there's not enough variation in shapes among trailers to make significant differences in fuel efficiency, especially over the relatively small distances most travel.

Surface area presented to the wind is of course another story...

Francesca
SA is a function of the 'shape', these are not mutually exclusive...
__________________
Dave_L is offline   Reply With Quote
Old 02-03-2013, 09:51 AM   #33
Senior Member
 
cpaharley2008's Avatar
 
Name: jim
Trailer: 2016 2ndGen Escape19 Prairie Schooner pulled by 2014 Dodge Ram Hemi Sport
Pennsylvania
Posts: 6,398
Registry
I was under the impression that when the new "towing" standards were published awhile back these also included "frontal area" requirements. Some auto manufacturers (Ford and Chevrolet) are using the FA numbers in calculating the capacity of their vehicle's towing. Known as the "Kite" effect, the calculations take into consideration of the trailer's frontal area and the impact on the tow vehicle. One trailer manufacturer, The Element, mentions meeting the the 60 s/f OEM limitations.
https://www.fleet.ford.com/showroom/...kchrtApr08.pdf

As far as weight, on the truck diesel forums it is all about the frontal area, NOT WEIGHT that impacts their calculations.
__________________

__________________
cpaharley2008 is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
More sleep space for us Bigfoots Myron Leski Modifications, Alterations and Updates 4 04-22-2008 03:49 PM
Bigfoots, and this & that.... Lizbeth General Chat 17 03-27-2006 07:16 AM

» Upcoming Events
No events scheduled in
the next 465 days.
» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 02:38 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.