Why have the Automakers refused the boat tail design?
 

Just wondering what peoples opinions were on why automakers have not started adding boat tails? Seems like it would be a low hanging fruit to increase FE without adding much cost or retooling.

Could it be the marketing gurus objections?

Problems parking a whale tail in the supermarket lot?

Reluctance to change? I remember the huge, non functioanl tail fins from the 50's & 60's?

Why not start a new trend here and actually change the worlds dependance on fossil fuel.

I was hoping some folks from the industry could shed light on this question.

Mainly because fe is so far down on the list of priorities. Heck, $4 gas is BARELY able to get people out of sub-20mpg pickups and SUVs... and for many, fuel expenses aren't the biggest operating expense after the loan, insurance, repairs, and such are combined. We will probably have to wait for much higher fuel prices and/or a "worse" economy (in quotes because in spite of all the media hype and water cooler talk, a look around reveals quite a lot more people than ever before enjoying the trappings of wealth than the sufferings of hardship) and/or some sort of catastrophic event to see a widespread attitude shift that values fuel efficiency.

People are still in ego-driven mode, that is, logic isn't the dominant factor in their vehicle selection; what they think will impress the opposite sex or the people at church is still the biggest factor. Current mass psychology favors aggression over efficiency.

In talking to a guy that was curious of my Songi electric bike, I pointed to a nearby SUV and mentioned that to drive that thing downtown (less than a mile from where we were) and back would cost over a dollar... you could tell by the look on the guy's face that the notion of cents/mile cost had never entered his consciousness before in his life... and even when it did, he was rationalizing how to justify paying over a buck to go a distance easily and quickly walked... :rolleyes:

For vehicles that make fuel efficiency a highly visible priority (Insight, Prius, VW L1) I think the tails could be longer but for sure there was an analysis of the pros and cons of such a move like parkability/garagability vs the incremental fe gain. The bias will change in favor of longer tails AFTER the consumer indicates they accept it and vote that it's worth it by buying such a design, or when there gets to be competition among manufacturers to have the slipperiest design, or something.

Some things are not done mainly because they don't really show up on the EPA mpg testing. :mad:

Frank, I gotta say, you're rational and excellent response leaves me wondering...Who are you and what have you done with the real Frank Lee?

Your responses in the past tended toward being rather biting and short worded but always conveyed a real intelligence at work. Lately though you expound more, and I have to say, are a joy to hear from. A very nice change indeed. Just my 2¢, FWIW. You have a full measure of respect from me.

Despite their fuel saving abilities, there are a few practical issues with boattails, too.

It's a lot longer.

Loading stuff in the rear of a boattail would put a lot of weight far aft of the rear axle, which is bad for stability. A long boot is fine, but you need to be able to get to the forward end of it to really use it.

Towing is effectively out - the hitch would need to be far forward under the tail, leading to long booms to get to the hitch. Clearance would become an issue. Putting the hitch at the aft end of the tail is completely out, the moment arm during swaying would seriously upset vehicle stability.

A boattail adds weight.


At least in NEDC, Europe's official fuel consumption numbers, it brings nothing as these tests are done on a dyno, not on the road so aerodynamics play no role.

My vehicle was selected because it got decent mileage for being an auto with 4 doors and still looking very sharp to all people whether they cared about mileage or not. Lets face it no one is going to know it has a 4 banger in it until we go to race which I would never put myself in such a situation with this particular 4banger for being an auto

If car manufacturers made something to the "best" of the specific cars abilities, then they have nothing to sell... They make a product based on the needs and style of today/and the near future, where car trends and manufacturers "think" the road is going to lead too. We as a consumer in our entirety Really determine where the market goes...
They Price what we pay based on what were Willing to pay For.

They make profit over the smallest things that "add" to the overall efficiency, or convenience of there Base Product creating the illusion that efficiency is an ongoing developement. (where we know it exist for YEARS, and is fairly easy to empliment) In a country where the ideaology is (go big or go home), nobody wants just an (effiecient car) to handle everyday needs, they Want the "Wants" and have to, have everything. We dont need some things, but in those (once in a life-time situations) we like to have the capability(cause its Cool) and the manufacturers can create that in no time instead...

There are less than 10 boat tails on this forum with 1,400 active members. That's less than .8% where pretty much everyone is concerned with fuel economy.

There is no reason that the rear axle could not have a much narrower track and be farther back in the tail.

How many people really tow with their car?

I think Frank hit it best Gas is cheap and people do not really car about MPG. Look at how many drive around in big SUV's and trucks everyday.

People buy what they think looks good. Get enough scifi movies to have them in and maybe people will think they are cool.

Gas doesn't seem cheap when you bought it for 19 cents a gallon. I guess people just don't see $4 a gallon as expensive anymore, must be that I am getting close to 62 in a few months. Looks like I can cover 210 miles on about $8.40 on the bike. About 4 cents a mile compared to less than a penny 45 years ago. I guess when you consider I was working 40 hours a week for under $23 take home pay in the summer of 1969 and gas was 32 cents a gallon, it would be the equilivant of minimum wage today.

It just baffles me that people drive anything that gets 12 MPG these days. Just grab a roll of quarters and throw one out the window every mile the odometer clicks off. Now add another nickel for the recent hike in prices.

That's $60 a week instead of my $8.40. There is a lot you can do with $51.60 a week besides paying those who hate us to do us harm.

regards
Mech

Not quite as old as you but yes I remeber the days of cheap gas to. But in the big picture $4 is still cheap. Every thing cost more since I was a kid.

Cheapest gas I've ever seen was 89¢ a gallon and I was in a car seat. Cheapest I ever bought was $1.99 when the market crashed in '08.

But back to the topic, because people don't want them. But designers are compromising, notice the rear hatches on new suv's? Also, truck tail gates have a small extension on them now. On a side note, the new '13 ram will have start/stop among other goodies, possible mid 20's combined score.

Like this!

http://www.roadandtrack.com/var/ezfl...l1-concept.jpg

I think it's safe to say that most consumers value form over function. That gives us 18-20 inch wheels on cars that will never attack a corner in anger and belt lines so high that to actually see traffic lights or gutters, you have to stick your head out the side window... If your head fits.

A lot of people are already reluctant to switch to hybrids because they "look stupid", with the aero-efficient shape applied to a relatively conservative two-box design. Imagine trying to get those poeple into something at looks even more unusual than a Prius hatchback or a Volt?

If a boattail were a $1500 option on a new hatchback and put you from 40mpg to 50 while your friends and enemies talk behind your back, would you buy it?

If a boattail were to cost you $500+ and take 200 hours of fairly skilled labor and body work while alienating you from your regular social groups, would you do it?

If a boattail were to be cobbled together (no offense to anyone) from random cheap or free materials while displaying a surface finish akin to a spray painted rock, who but we FE nuts is going to want it on their cars? We do because we understand the implications. Most people wouldn't be caught dead.

The fact is that to make a really quality looking boat tail (hat tip to 3Wheeler) you are looking at some SERIOUS time and money investment for a few extra MPG. The only way I see this working out for people is if:

1. You buy it new from the OEM designed to "work" with the car and removable when not needed, ie, a different hatch on your hatchback, seeing it as a ten year investment.

2. Make it fashionable like it was in the 30's...

Exactly. Cars are on the downturn right now as a hobby and people don't really look up to them for inspiration. Educate people and make economy something desirable- and for Dog's sake stop calling it "economy"! It sounds so cheap, like you're buying silverware from Goodwill! To make boat tails acceptable they're going to need a pretty substantial media spin.

You'll also need lots of accountability on aero claims. As we saw in the 80's (well you did, I was a baby) lots of companies like to make big claims or to put up a facade of progress while keeping things status quo. It's easier for them that way. You can't slide backward into better aesthetics and worse design/aero. You can't rely on EFI and engine shutoff to save your butt.

Right now, you can rely on consumers to blindly trust their emotional reactions.

BRAVO!!!! :D
It is stating the obvious but VERY spot on! :thumbup:

oh yeah, that car!
I see hundreds of those a day.........:rolleyes:

example:

Back in the 80's, chrysler got a bad rating on the Omni (built to bring the company out of bankruptcy) becasue when consumer report JERKED the steering wheel back and forth, the car continued to oscolate(sp) back and forth.
Chysler said it was an unfair test because:
1. No one drove like that
2. The light weight front wheel drive w/ uneven axles where inherently less stable than rear wheel drive cars that the test was designed for.
Consumer report said:
In the rare 'emergency' a consumer would perform that manuver.

I promise you that "RANDOMLY" narrowing the rear will have unintended negative results.
The car in the picture could not servive the lowest comon consumer.

Example: my 1999 Jag Vanden Plas had a stretched body (7-8 inches in the passenger floor board) I could feel the difference when turning on the rear tires.

SOme here may find this hard to believe :eek: but there actually is science and engineering that goes into every part of car design.......Things are where they are for a reason. (physics, marketing, regulations, dynamics, aero etc) :thumbup:

Remember that those are not yet available in the US. And they have a very low center of gravity, making the width not such a problem. Do you think people have trouble driving kei cars around in Japan? I haven't seen dimensional specs on the XL1 but would bet it's not wider than Japan's ubiquitous city cars. Look at the coveted Autozam (Mazda) AZ-1

It's not on sale yet, and still undergoing testing: 2014 Volkswagen XL1 Caught Testing - First VW XL1 Production Mule Photos - RoadandTrack.com

It's not that they don't make "boat-like" tails, it's that manufacturers can't always get people to buy them. Many of the 70s and 80s hatchbacks have awful reputations these days, because some sort of negativity got associated with them and it stuck. The Ford Pinto for example is synonymous with bad reputation because it got stuck in the public's mindset that closing the door too fast would make it blow a crater in the earth... but for its day it was a pretty aerosleek car. I grew up with Pintos (parents had four, I had two more) and not only did none of us die (I was in the car for two hard collisions, we were not injured and there were no fires) - they were fantastic workhorse cars that did quite well on carbureted 1.6L and 2.0L 4cyls.
http://static.ddmcdn.com/gif/1971-19...pinto-1974.jpg

What else was relatively slippery in the back? This thing was designed with the idea of being slippery, and went a step farther than the Pinto by curving inward in three dimensions - from the sides as well as the roof line. But they were "too dorky" apparently, so again like the Pinto, hated and seen as a joke.
http://www.pacerfarm.org/p2tf.jpg

The 80s were like the decade of the hatchback, with all sorts of non-square-backed hatches that may not have been boat tails exactly but had an anachronistic slope to their hatch we barely see anymore - but because they seem endlessly associated with pimple-faced pizza delivery guys and such they'd be a tough sell today:
http://global.oneighturbo.netdna-cdn...e-cat-1985.jpg
(kinda has a prius-like profile)

http://sphotos-b.xx.fbcdn.net/hphoto..._1468276_n.jpg
^ that was my first horse... a little vanity here if you'll indulge me

Pontiac tried to aero the tail end of a minivan, but like the Pinto, the Pacer, the Scirocco, the Escort.... the Aztek was a highly functional car that everyone decided they hated because to the buying public automotive coolness is inversely proportional to practicality.

It's not as though there is zero boat action going on today though, many of the newest hot hatches are finishing a bit narrower in the greenhouse than the windshield - leaving the car itself short and easy to park, the cargo area tall enough to easily access and fill, enough head room in the back... yeah it's not a basjoos or anything but it's not ignorant of aero:
http://www.automobileinsight.net/wp-...%20%282%29.jpg

I don't think we'll see a full on submarine for the road... cities aren't getting any more spacious and while a few people are willing to make boat tail compromises, it would be naive to deny that the compromises exist.

Why don't manufacturers make boattails?
 

This question could just as easily be stated, "Why don't manufacturers make ____ ?" And you fill in the blank.

Manufacturers state that it costs them millions to bring a new vehicle to market. And no matter how many methods they have to make vehicles more fuel efficient, lighter, lower cost, or whatever you particular desire might be -- the bottom line is that car manufacturers are in business to sell the most vehicles and to make as much money as possible.

So they are typically very conservative, adverse to risk, and inclined to only make cars that would hopefully have mainstream appeal and generate massive profits.

Otherwise manufacturers would be making the Aptera, or a VW 1-Liter type car, or perhaps a clone of one of the winners of the Progressive Automotive X-Prize competition of recent years.

For the most part, for all of us ecomodders, we should NOT look to auto manufacturers to make anything of any signifigance relevant to our interests in our lifetime.

That's a big part of the Aztek drum I keep beating... it was a big risk, and if everyone gets over their opinion about its looks it's actually a very easy machine to live with (the two friends I know with Azteks love theirs, and I envy.. they do almost everything I do in a grand cherokee but with more cargo room, an easier to clean/configure interior, less fuel used and better road manners)

A similar thing goes with the Isuzu Vehicross.. when it was introduced it looked like nothing on the road and few people liked it, and Isuzu is now gone entirely from America - but today's latest generation of small SUV's look a heck of a lot like Vehicrosses.. Granted the Vehicross isn't so easy to live with (my brother in law has one) and few people grok that it's more Wrangler than WRX..

The Nissan Juke brings America a tiny, turbocharged engine (isn't that something we applaud here?) and highly controversial looks - again they don't seem to sell well, I never see 'em on the road.

Automakers don't take many risks because the public doesn't reward those risks, we're addicted to buying nostalgia like Mustangs and Camaros and Challengers and Power Wagons because we once rode in our older cousin's and it was kool.. :rolleyes: and whole cultures of luddism appear throughout motoring culture, get on any Jeep board and you'll here a bunch of cave men grunting that no real man drives an automatic, and half of them will argue that carburetors are better than fuel injection or electronics, even to the point of citing their own unwillingness or inability to understand modern systems as the main reason for this opinion (but it's the electronics' fault, for being too... moderny... :rolleyes::rolleyes: ) .. so many people are stuck in the past or dreamy-eyed about how things used to be, romanticising whatever crap was good enough 30 years ago because nothing better had yet come into existence. It's an idea that permeates culture so much that even when I actively acknowledge the fallacy I find myself falling for it from time to time.

So until such time as the public is willing to buy the future with their money, the future won't happen.

shovel,
I have always been a fan of the vw fox wagon:
http://i678.photobucket.com/albums/v...lightsside.jpg

Not sure if it is very aero.....but it certainly fits the 'utilitarian' mold!

the white sciroco's roof line is MUCH lower than the prius

I got a freakish number of miles out of a 93 Fox. Mom bought it brand new in 1995, having been an unpopular color/option combo and the odometer stopped working around 330k miles, i drove it a couple more years after that and sold it in running shape to a girl who wrecked it during the test drive... - the thing which struck me back then was how tiny the radiator was, and how despite that there was really not much heat under the hood - probably in part because the odd longitudinal engine + front wheel drive configuration meant tons of room for air cooling. It got decent fuel mileage, maybe because it didn't turn so much gasoline into heat.

The weirdest thing was that it felt like the gear ratio for 4th and 5th seemed pretty much the same, you'd shift 1-2-3-4-5 and it felt like shifting out of 4th, and then right back into 4th again. I did really like the way they did the shoulder belts in the front doors... worked really well and had no way of failing like those damn attack belts that Tempos and Accords once had..

ok if the goal is to save fuel , then your driving habits and vehicle you choose to preform the majority of your driving duties is the biggest piece of the puzzle, if you drive 4000+ pound large displacement car truck suv and want to feel the acceleration you will burn more fuel..... if you place the imaginary egg under the gas pedal (and brake pedal for that matter) you would likely have better mpg's vs a boat tail . then try changing to a fairly small or mid sized 4 cyl with a turbo /diesel , and keep in mind driving with the mass of your vehicle and what it takes to accelerate that mass. then existing technology (or older tech) can be very good on fuel , without constructing large difficult and costly body modifications (though dont stop modding just pick your battles)

Exactly. When you look at a car, the engine isn't spending a majority, even a plurality of the energy removed form the fuel to overcome the fluid force of the air around the car. The engine is devoting most of the fuel to heat up metal near it. Then, when everything is heated properly, the engine can start providing torques to the drivetrain.

Automakers sneak the boat tail shape into their product through hatchbacks and Kamm-backs, and that's really all that needs to happen.

From my own private polling (casual gas saving discussion) people can't even handle the looks of a Prius! Not it's slowness, nor efficiency, it's technology or price, their problem is the look of it. Humans are doomed.

http://upload.wikimedia.org/wikipedi...urus_Sedan.jpg

I often wonder how a design like this one got accepted by the public.
This car certainly resembles a 'submarine' yet people bought it.

Sad that all that swoopy style was overdone, and the Cd actually stayed the same as the previous generation ( actually worse .32 vs .29 on a Sable ) All the angles were wrong for good aero on that car.

People like the looks of the Tesla Model S, generally, and it is lower Cd than the Prius of the original Insight.

Another well stated observation:thumbup:

design
 

Hucho credits Daimler-Benz with the revival of boat-tailing as of the late 1970s Mercedes-Benz cars.
I've been thinking about this thread since it was posted,and while out on material runs I'll stroll past the tails of vehicles as I walk to and from the store.
I see more boat-tailing than ever.Sure it's embryonic but it's there.
As a 'Valley Boy,' growing up in Southern California,I,along with many friends observed that features we'd see on 'custom cars' taking form in many a open- door garages,would in a few years time,show up on production cars from the Big-Three.
Anything the Speed Equipment Manufacturers Association was selling to a teen or young adult 'today',would end up in the auto showrooms in a few years time.And they'd get their 'price premium' for the added features.Low down payment and low payments.
It looks like there are 'drivers' in the market.If boat tails are ever perceived as high-performance equipment,we might see the 'Fast and the Furious' phenomenon take off with relation to real aerodynamics.
Substance could overshadow 'appearance.'
Bonneville should be interesting.The T-100 garnered much interest and photographs.Even George Poteet's crew turned camera it's way.
If JethroBodine and I (any others?) can actually make it out there and run,it could affect how the 'girly-man' boat tail is perceived.
Coming home from an aborted testing trip (foiled by hurricanes) a few years back I tailed a U.S.Homeland Security Chevy Tahoe at 107-mph for quite a few miles before I could figure out who the --l these sons-of-b------- were,while they emptied America's oil stockpiles single handedly.
The truck will 'run'! It's faster than many smaller cars of greater horsepower.Hope to know the end of the envelope in September.After which,a bunch of folks will 'know' what these silly things can do.
Tip of the iceberg?:rolleyes:

That is also one of the reasons I'm working as hard as I am to make it.
Especially since, at 5'9"- 240 lbs, "girly" is seldom( if ever) used to describe me;):D.

I don't believe they've refused it per se. IMO, rising gas prices will inevitably push automakers to pursue down the path of drastically refining the car's aerodynamics. The evolution towards a mainstream boat tail will happen, but it will be introduced in baby steps as the consumers do not like drastic and sudden changes, for the most part.

The automakers, or at least the engineers, know very well that a boat tail can greatly reduce drag, but the marketing/design department usually dictates the mold in which the car will take shape.

Seems to me that roles are reversed. The engineers should come up the best possible design and the marketing should sell that design to the masses.

About the closest I have seen to boattailing on a car has been the late nineties Buick Riviera and the Taurus I posted earlier.
Too bad they apparently do not pay attention to the function over form, since despite the obvious boattailing , I seem to remember the cars Cd in the low thirties .

http://www.thewayautoca.com/images/3434-5.JPG
http://images1.americanlisted.com/nl...a_27480387.jpg

Always thought that Riviera was beautiful. I bought a 95 with the Supercharger, but I never really tried to hypermile the Riv. It would get 30 MPG at 70-75 MPH and put you to sleep doing it. It coasted forever, even if you left it in drive. I thought the CD was listed at .30 but it sure acted like it was lower than that.

regards
Mech

Old Mechanic -

Pretty car. I liked how they "creased" the top of the rear quarter panels. I called them nano-fins, ;) .

CarloSW2

then the actual riviera boattail
http://www.buick-riviera.com/picture...s/01fact2a.jpg
i always thought that body style was epic... maybe not good, but epic

Any one lay the templat over it? It looks pretty good.
Also I like the car.

It was enough to sink the Titanic ;)


Unless the US and EU change their fuel efficiency testing to actual driving tests, aerodynamics will not play a major role.

I thought everyone here was familiar with that car already.
You guys missed the " beauty shot " though :
http://www.buick-riviera.com/picture...yes/Rob003.jpg

Makes one wonder if you could use that glass on a boattail for your own car doesn't it ?
But that's a different topic.

And the Taurus died (in that generation) while the CamCords of the world lived on... and on... and on... and...

The previous comment on the Prius... spot on. people were lionizing the Civic hybrid and Accord hybrid when they came out... why? Because they were eco-misers that looked like "real cars."

Dodge's "cab-forward" designs met with stiff resistance when they first came out, too.

Slowly but surely, automotive fashion is forcing people to accept sleeker noses, taller tails and more fluid shapes... by disguising them with gaping, mawish grilles (which, laughingly, are almost completely blocked off), gigantic headlamps, split-level trunks and huge wheels and wheel-wells.