Roof rails ...whats the use??

Hi All,

First of all I am not very sure whether this is the right section for this thread. However though it is related to car technology I am posting it here.

What I want to know is that, whether roof rails provided in cars like Wagon-R & spark have any value other than the looks? I heard somewhere that they are useful in Tall Boy designs. Is it true and if yes then please explain how they provide any value additions? Do they contribute in aero dynamics of the car ?

this is not an urgent request, but for knowledge sake I would like to know more about it.

Roof rails are used to carry bulky cargo or sporting equipment overhead that can use special roof mounts which can be fixed on to these rails.

They are a modern version of the old 'luggage carrier' except that they are designed to be mounting points rather than carriers.  You could carry your kayak/surfboard/bicycle or even luggage in special containers that use these mounts (Thule, for instance).

Last week we saw an Innova with a roof-mounted DTH antenna (Dish TV on Wheels) for Television reception.  the antenna was mounted on the Innova's roof rails.

DUPLICATE POST> Please delete~!

So it means it has nothing to do with the aero dynamics of the car ?? But why would they (Maruti) provide roof rails (If it is used only for luggage) in Wagon-r which has great boot space and not in a car like A-star with virtually no space....

Roof rails help transfer the load to properly reinforced points on the body, so that substantial loads can be put on the car top. Some over sized loads (like kayak etc, as rightly pointed out by Steerroid) cannot be put inside, they will require you keep your rear door open or would be otherwise inconvenient to carry inside.

Notice that the car rails are only useful if the car is a 5 door model or a MUV/MPV/SUV, so that the top extends right to the back of the vehicle.

BTW hauling load on the roof is not the most prudent way, FE-wise. I was amazed people can be as foolish as mounting a Dish antenna on roof rails. It will be a complete disaster aerodynamically, and will act like a parachute behind a fighter jet - it needs to be deployed only when coming to a stop, as it helps drag the jet back. The dish may also not survive the stress of driving at ~60 mph /100 kmph - the load on the mounting will be enormous! 

I think you need to see the product before jumping to conclusions & damning it thus.  We travelled comfortably at 100 kmph - it is a DTH antenna made specifically for automotive use, so we should give the manufacturer some credit.  Our ICE tuner who has it in his car is also a person of above average intelligence, who wouldnt spend 1.75 lakhs to topple his car.

Here's an image from The Telegraph (Calcutta).  You can find more information by googling "Dish TV on Wheels".

Further information is available at Dish TV's website:

http://www.dishtv.in/Static/tvonwheelsdemo.asp 

Hey Steeroid - Thanks for the info.

I was not aware of the product, as it is a very unlikely one in consumer electronics field. The premium demanded for the product is huge, and I did not think that such a product would sell.

The antennae look like they are phased arrays, a technology used for AWACS early warning radar aircraft. The antenna consists of several individual dipoles, connected through a switch capable of phase shifting the signal. Such an antenna can be 'tuned' to look at any given direction in the sky, and its operation is possible only through high tech. RF hardware and huge processing power to compute the phase shifts required at individual dipoles to arrive get a useful signal strength for reception.

Due to enormous costs involved, the use of this technology was limited to Military applications, and not civilian use. (remember seeing those 'flat panel antennas' moving on top of destroyers/frigates?) Hence my apprehension.

Looks like this civilian application foothold will help bringing the costs down for everyone, and soon we will see mass introduction of this product. (How soon is anybody's guess, though)

Wow that is gr8 then how is signl quality.Doesit get affected if it rains.

Signal quality is actually quite good.  Very impressive piece of equipment - it better be, at the prices they sell this at !!!!