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Purpleline Wind Deflector - Aeroplus


lottie
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I have seen an ad for a wind deflector that is said to reduce fuel consumption (by up to 15%) and aid stability when towing.

 

Has anyone any views on or experience of these?

 

See for example:

 

http://www. caravanmoversonline. co. uk/purpl. ..e/aeroplus. html

 

If they really save 15% on fuel (I'd like to see more detailed results on that) that is equivalent to saving about 2p a mile on my car (fuel costs reduced to 13p a mile instead of 15p) when towing. So at £100 you would need to tow 5,000 miles to recoup the cost of the deflector.

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These deflectors did seem to be popular many years ago, not sure about the effect as it must depend on the aerodynamics of the car as well as the caravan and the distance between the spoiler and the 'van. I look forward to hearing more about the device.

 

Gerry

2005 Kia Sorento 2. 5 Auto towing 2011 Conqueror 645

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I have seen an ad for a wind deflector that is said to reduce fuel consumption (by up to 15%) and aid stability when towing.

 

Has anyone any views on or experience of these?

 

See for example:

 

http://www. caravanmoversonline. co. uk/purpl. ..e/aeroplus. html

 

If they really save 15% on fuel (I'd like to see more detailed results on that) that is equivalent to saving about 2p a mile on my car (fuel costs reduced to 13p a mile instead of 15p) when towing. So at £100 you would need to tow 5,000 miles to recoup the cost of the deflector.

 

Hi Lottie

 

As Gerry says they were all the rage some 20 years ago, and yes I had one (and only went to the tip last year) so they

are not a new thing, but from what I remember, they did seem to help with areo-dynamics a bit, but they were only any

good if you had a estate, as the deflector needed to be right at the back of the car, so if you have a boot it did not work

as well.

 

I wal lucky I had a Caviler estate and spent many hours moving forward/backward to get the best out ot it, and right at

the back was the best, don't know about fuel saving, as it was a company car, I never paid for the petrol (perk of the job)

 

ps notice in the advert it is close to the back on a estate !

 

So at £100 are they worth it ? its your money !!

 

Radiotwo

Edited by RADIOTWO

Steve - Land Cruiser Amazon Auto + Pageant Series 5 Champagne

The match between car and caravan is perfect in accordance with a mix of European standards. However, according to the British Towing Code the percentage (loaded caravan / kerbweight tow car) is 49%.

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Yes. ...I had one as well and no end of chips out of my Sierras roof fitting it. ..in fact just about everyone I knew then had one. .all on saloons. Positioning was critical as I remember one caravan overturning on A19 at Mount Grace Priory Bank and it was felt that turbulence between the wind-jammer and the caravan had made it unstable!

 

But that was then. ...20 something years ago and basically it was an adjustable blade and that was it.

 

rgds

 

geoff

Kia Sorento KX-1 CRDI 4WD towing an Elddis Affinity 530

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We too had one years ago - wasn't there something about them affecting noseweight in certain circumstances where it created a lift effect over the hitch area? Now this is a question Doc would have answered.

NE Scotland

 

Unicorn Valencia pulled by Merc E280 cdi sport

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Next time you are out look at an Artic fitted with wind deflectors. These are designed to have the minimum gap between cab and trailer as any gap over 2 feet makes them practically useless. The fuel savings with these are about 2 %. The critical thing here is distance as the wind slammer will create it's own turbulence just behind it. This is what is known as drag. If there is very little gap the drag will be minimum as the wind will be passing over the side of the next object. This however will not be a total loss as disturbed air can sometimes be easier to pass through with a bluff fronted van such as a Bailey probably benifitting most.

 

So as to the purple line deflector I would really doubt 15% savings and reckon that this could only have been achieved with a tall mpv with a dead straight on wind.

 

Another thing to keep in mind is it would be very unwise to travel at any speed with this device fitted as the cars centre of pressure point will be moved.

 

As to the previous posters quection re the noseweight, no it will not increase noseweight but may critically alter the weight being exerted onto the rear axle due to drag.

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The number of people who left them on when not towing was amazing . . must have negated any possible benefit when towing . . I suspect 'vans are (slightly) more aerodynamically efficient these days any way and as John says, you've got to travel a long way to show any (possible) saving . .

 

the ad says 'up to 15%' . .

 

a 0. 5% saving would still meet that statement . .

 

when they say 'guaranteed minimum saving of xx%" then I might believe

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I think we had these back in the 60's -- and wind deflectors for when you opened the windows as well. .

 

What goes around comes around :D

Volvo S60 D5 (now sold 😥) new Vauxall soon
Happy to meet, Sorry to part, Happy to meet again
48 Year Member of The Caravan Club

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My dad had the Volvo branded one. Dunno if it saved any fuel but it kept flies of the front of the 'van.

2010 Volvo XC70 D5 SE Lux (2012 V60 D5 All Wheel Drive R Design after March 12!)

2012 Swift Conqueror 480, with Omnivent, Mini Heki in Loo, Mudflaps and ALKO Mammut Mover

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Another thing to keep in mind is it would be very unwise to travel at any speed with this device fitted as the cars centre of pressure point will be moved.

 

As to the previous posters quection re the noseweight, no it will not increase noseweight but may critically alter the weight being exerted onto the rear axle due to drag.

 

I can imagine an insurance company being very interested in these effects in the event of an accident claim. ...

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I wonder if a roofbox might be better and more useful! We had a slight improvenment in economy last year in Germany but that could have been due to travelling at slower speeds than in France.

 

David

David - Milton Keynes

Bailey Alliance 66-2 Motorhome for holidays and a Kia Venga for home.

 

Caravan Travels

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Next time you are out look at an Artic fitted with wind deflectors. These are designed to have the minimum gap between cab and trailer as any gap over 2 feet makes them practically useless. The fuel savings with these are about 2 %. The critical thing here is distance as the wind slammer will create it's own turbulence just behind it. This is what is known as drag. If there is very little gap the drag will be minimum as the wind will be passing over the side of the next object. This however will not be a total loss as disturbed air can sometimes be easier to pass through with a bluff fronted van such as a Bailey probably benifitting most.

 

Some modern lorries nowadays have the deflector built into the trailer. 20 years ago caravans were very vertical slab fronted, they have changed a lot since then. My car's MPG only drops from 28 at a fast solo cruising speed down to 25 when towing at my usual steady towing speed, so I don't much could be done to improve on this.

Bailey Pageant Monarch Series 5 2004

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As to the previous posters quection re the noseweight, no it will not increase noseweight but may critically alter the weight being exerted onto the rear axle due to drag.

 

Didn't say it increased - I thought in certain circumstances it created lift and thus lightened the noseweight.

NE Scotland

 

Unicorn Valencia pulled by Merc E280 cdi sport

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I found the benefit was very noticable as the speed increased a little over 50mph, this was enough to make you look to see if the van was still attached!?

I used a similar designed one to the Purpleline version and the wind deflected down the side of the van can aid stablity when trucks pass, but, below 50 I doubt you will get any improvement in mpg.

gary1s.gif

 

Arc Systems are specialist Carver caravan product repairers, committed to providing a comprehensive service as well as spare parts for these popular heaters.

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I found the benefit was very noticable as the speed increased a little over 50mph, this was enough to make you look to see if the van was still attached!?

I used a similar designed one to the Purpleline version and the wind deflected down the side of the van can aid stablity when trucks pass, but, below 50 I doubt you will get any improvement in mpg.

 

I think it is at higher speeds that the air resistance (drag) of the van has most impact on MPG. Air resistance increases by the square of the speed. ... double the speed from 30 to 60 and the air resistance is four times as great. So your 'over 50' experience sounds spot on. The quoted saving of "up to 15%" suggests variation which I guess will depend on various factors - tow car, van design etc but probably also speed. I would expect little benefit at slow speeds and maximum at maximum legal towing speed - or into headwinds. A 10 mph headwind will make the drag you get at 50mph like 60mph drag. ...which will be over 40% greater than 50mph in still conditions.

 

Is there a current alternative to the Purpleline product available?

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Would be interesting to try before buying and see if it did make any savings. But big problem for us is that on big holidays we have bikes on the roof of the car so no chance of using one on the longer drives anyway!

"Scars are souvenirs you never loose"

2010 Swift Charisma Freestyle 550 + 2007 Nissan Pathfinder Aventura.

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