Jet dragster safety feature applicable to Indy cars

[Franklin]

Dennis Roslanski has mounted on his jet dragster just forward of each rear wheel a small VERTICAL highly cambered wing. According to Roslanski, it expands the envelope a bunch in which the car remains directionally stable. (Roslanski's approximately 1,300 pound car runs 300 mph.)

[Peter Mallett]

Exactly what is your point here Franklin? I believe these things have been seen in F1 (as at Monaco) and indeed Lotus ran them on the Turbo F1 car back in the Senna days.

[Franklin]

The point, Peter, is THEY HAVE NOT. Effective vertical stabilizers have not been used in open wheel racing since the early sixties.

[Peter Mallett]

Forgive me but your description is that of the small side wings which I have observed in the last twenty-odd years of motorsport. Obviously I misunderstood you but I ask again. What exactly are you asking or suggesting? For a start an F1 car has abundatly less BHP than a dragster. A dragster can hail an awful lot more aerodynamic drag than a F1 or Cart car. Also an F1 or Cart car needs to turn corners whereas a dragster daren't. So, I suspect that these wings were dropped when they were found to be an unneccesary drag and of no use in a cornering situation.

However, if you are suggesting these things be used as a safety device, I would respectfully suggest you think again, because more downforce leads to lower mechanical grip, leads to less overtaking and therefore less racing.

[Franklin]

You HAVE NOT seen them on F1 cars, Peter, because I'm talking about wings NOT positioned in the horizontal plane but instead positioned IN THE VERTICAL PLANE.

[Franklin]

And since I'm talking about wings positioned IN THE VERTICAL PLANE (the one 90 degrees to the ground) I'm NOT talking about anything that adds downforce.

[Peter Mallett]

Originally posted by Franklin
And since I'm talking about wings positioned IN THE VERTICAL PLANE (the one 90 degrees to the ground) I'm NOT talking about anything that adds downforce.

Ahhh.

You mean like the rear end of the Penske a couple of seasons ago.

They also had them on the Turbos in the 80's at the rear end of the side pods. Get a look at the Brabhams and the McLarens from around 1984.

BTW. I guess you mean "perpendicular" when you talk about 90degs to the ground. Just like the bargeboards on the current F1 cars.

Still. I ask again. What exactly is your point?

[KC]

Vertical winglets have been used in all manner of aerodynamic vehicles for years. Gates Learjets use them on their wingtips to create beneficial vortexes that increase lift without increasing drag. They trap more air on the wing surface that would normally slip off away from the wing. The rear wings of every race car employ some sort of vertical plane to increase the efficiency of the wing element. This works especially well for straight line race cars because of the stability imposed by a rudder-like device, however, it also makes them much more susceptible to cross wind instability. Ask any winged sprint car driver what its like to race with a crossing wind with the massive side plates they run.

[Franklin]

You mean the Sprint cars where in a lefthand turn the cars ROLL TO THE LEFT THUS KEEPING THE INSIDE TIRES LOADED? (Because of the large vertical surfaces mounted on the wings.) You know, the same cars which were turning 140 mph laps at Bristol? (About 15 mph faster than the Winston Cup cars.)

[Franklin]

Before it gets lost in the shuffle, the basic principle is keeping the Center of Pressure BEHIND the Center of Gravity. It's why people started putting feathers on arrows. The shorter the distance between the Center of Pressure and the Center of Gravity the more pressure (i.e., the bigger the tailfin) you need to keep the vehicle from spinning. Since barge boards are located FORWARD of the Center of Gravity, they may actually be directionally DESTABILIZING.

[Peter Mallett]

Interesting point about the bargeboards Mr F. You seem to be suggesting that designers are increasing instability. If so then why have barge boards at all? Anybody care to explain this one?

[KC]

I would think that the barge boards have soemthing to do with drag in that they can be shaped to limit the air flow in to the radiators. These openeing represent one of the largest areas of drag on the car and the barge boards can eb shaped to allow only enough air in to keep the motor cool. They can then be shaped for each individual track. Hockenheim probably uses wider barge boards as the ram-air effect is higher because of the straights. I could be totally off base.

[Franklin]

Barge boards are for drag, but in a different way. They deflect high energy air into the low pressure area behind the front tires. They MIGHT also serve as air dams to keep turbulent air out from the underside of the car and the radiator inlets. The size and shape of the radiator inlets are what governs the air flow into the radiators.

[Bluebottle]

The best way to make drag racers sake is obvious- put them on rails,- France holds the current record for an electric powered train at, I think, over 200 mph- Britain holds the record for Gas turbine, Diesel, and steam power (Mallard, at 126mph) and these things weigh hundreds of tons and don't do corners- right up your street Franklin!!
(I believe the US military has a 'rocket sled' which runs safely on rails at great speeds- maybe you should have a go?)

[yelwoci]

Bluebottle,

Please!

"these things weigh hundreds of tons and don't do corners- right up your street Franklin!! "

Somewhere up in the north of England...it's a dark place that us southerners rarely venture into.....they built a banked curve so that 'The Flying Scotsman' and then subsequently 'The Mallard' could break the record for London to Edinburgh. I believe it has a 400yd radius and a 15deg bank and the train took it at over 100mph with a full complement of carriages and passengers.
Some train spotter may know more details (and more accurate).

They did do around corners though I concede the turning circle was similar to the drag cars and Franklin's mind set.
(Sorry F. cheap dig <vbg>)

IanC

[Bluebottle]

Yes, they corner like they're... er...on rails!!
I think Mallard broke the record somewhere near Grantham- it was not supposed to be a record attempt oficially- they just happened to have a dyno car and record book officials handy!
The driver chose to ignore the smell of cooking bearings and pushed the engine "to the max" as the youth of today say!- I've got more stuff on this somewhere, but this is a motor racing forum!!!.......

[KC]

Is this what you were talking about Franklin? This, I believe, is an Alfa Romeo Disco Volante LeMans car from the mid to late 60s.

[TimD]

At the risk of being a real anorak here, by the look of it, I'd say that was a CD-Panhard 3. And if the 44 on the door is anything to go by, I'll call it as the 1964 Le Mans entry of Guilhaudin and Bertaut.

Great photo, crazy little car!

[KC]

You are most likely right, I was just taking a shot and it reminded me of the old super funky Disco Volante.

Very Austin Powers looking wouldn't you say? ;D

[TimD]

Oh, YEAH, baby!

[ma]

Those vertical wings are there to decrease the lift created by such a large, fast spinning tire. Not allowed in CART or F1, etc.

Barge boards are used to help move the center of pressure forward by creating a high velocity ( low pressure) area tha help evacuate air from under the car that would have normally travelled to the rear underneith the car, they have nothing to do with filling the void behind the front tires.