Rockets With Fins

[lobsterbark]

In cartoons and such, most rockets have fins. But if you think about it, there are almost no irl rockets with fins. I think the Soyuz has small fins, and the V-2 has fins, and if you stretched it, you could say the Space Shuttle and Buran has fins, but thats it.

[Canopus]

Swivelling engines can steer your rocket with out adding additional drag. The V2 had the big fins in order to be self stabilized like a dart and to help control. It had no thrust vectoring and was only able to control itself due to small "Strahlruder" control surfaces that where suspended into the exhaust of the Rocket. I think i even heard that the second generation of Saturn V's would have got rid of their fins.

[chobit-389]

Also bear in mind that those cartoons started their rocket designing in the 30s-50s, where there pretty much was no rocket science to speak of (well, then Vostok and Mercury).

Besides, in the 50s, EVERYTHING had fins!

[ROFLCopter64bit]

Also bear in mind that those cartoons started their rocket designing in the 30s-50s, where there pretty much was no rocket science to speak of (well, then Vostok and Mercury).

Besides, in the 50s, EVERYTHING had fins!

Even fish!

[Crush]

Many rockets used to have fins, but they fell out of favor because modern computers can stabilize a rocket faster and more efficiently using active thrusters.

Early versions of the Ariane rockets also had fins (version 1-3), but they were dropped somewhere in the 90s (the ariane 4 has models with and without fins, the ariane 5 has no fins).

[bsalis]

Besides, in the 50s, EVERYTHING had fins!

Bring back the fins!

Also, the Saturn V had fins.

[Canopus]

Bring back the fins!

Also, the Saturn V had fins.

Yes it had it had fins but following versions wouldn't.

[Flymetothemun]

Also bear in mind that those cartoons started their rocket designing in the 30s-50s, where there pretty much was no rocket science to speak of (well, then Vostok and Mercury).

Besides, in the 50s, EVERYTHING had fins!

Jes' Sayin', but I think those helped with aerodynamic stability. You never saw somebody with fins on their car skidding all over the road. Jes' Sayin'.

[TwoHedWlf]

Jes' Sayin', but I think those helped with aerodynamic stability. You never saw somebody with fins on their car skidding all over the road. Jes' Sayin'.

Oh?

[Flymetothemun]

Oh?

It was a joke. And i'm talking about everyday life, not a race.

[chobit-389]

Fins on a car have no say in aerodynamics or stability. Maybe if the car produced it's own lift but otherwise, no, cars are too heavy for aerofoils to make a difference unless said surfaces are designed to keep a lightweight racecar's wheels on the track

[OdinYggd]

Pretty much.

Racecar fins are very different from rocket fins or airplane wings.

Their purpose is to provide additional downforce on the body of the car to compensate for a lack of traction when moving at high speed. For the most part they have no controllable surfaces and do not produce significant lift.

[Rockcoole]

What if we put the fins the other way round?

*clearing showing my knowlage of areodynamics*

[RawChicken]

Then you have flying cars!!

Ahh...if it was that easy... (sight..)

[OdinYggd]

Then you have flying cars!!

Ahh...if it was that easy... (sight..)

Sort of. You'd need to attach a prop to the car's engine, and the 'fins' would have to be more like wings with enough lift to carry a car's heavy frame.

Alternately put the fins on a stick and make the engine spin that, for a helicopter.

But cars don't fly very well. Despite having a power to weight ratio better than the engine in the Wright Flyer, they are just plain too heavy. My car in the driveway right now is over 2100 lbs, it would take quite the wingspan to get it off the ground.

[chobit-389]

A helicopter is far more complex than just a few blades on a rotating shaft.

Speaking from experience they are way WAY complex. Gliders to C-130? No problem. The moment the 439th let me near one of their Griffons... I still have nightmares...

Now as for Odin's car (and I've had to translate to yankee terms, so I'm not sure) at 2100lb, strap some control surfaces on it, a wing area of maybe 140-150 sq ft, you COULD achieve lift... at about 102 knots (117 mph)

[RawChicken]

Yeah, helicopter wings are pretty damn complex. Even simplified RC models.

Nother problem with a car achieving flight is that once its airborne, wheels stop giving you speed so you loose speed and lift. You would need a mechanism to transfer the engines power to a propeller!

Sounds like a nice weekend project!!

[Warscribe]

transferring engine traction to a propeller wouldnt be much of a problem, but the additional controls so the prop doesnt give you immediate stall would require even more weight on the frame.

from what ive seen, RC helicopters arent that much simplified but the controls are. What makes them look simpified is that they normally dont have to get more weight of the ground than a few grams (which is why theyre very fast on the controlling) and they dont need all the requisites for proper oiling and smearing. Also, (the basic ones) they dont have the hinges that change the wing direction, more advanced models have that, and thats why they can, for instance, fly upside down without changing motor direction

[OdinYggd]

Pretty much. I was just using a simplified example, the hub of a helicopter's rotor is incredibly complex and precise in order to make the craft controllable.

The wright brothers flew with an engine that produced 12 horsepower, with the engine weighing 175 pounds and pushing a craft that fully loaded weighed 750 pounds.

This gives a power to weight ratio of 62 lbs per horsepower.

My current car, with a curb weight of 2100 pounds and a 200 horsepower V-6 engine, has a power to weight ratio of 10.5 lbs per horsepower.

So really, if you could attach the shaft power of the engine to a propeller and provide an appropriate wingspan, you probably could make a car fly at a decent speed.

But all that aside, cars aren't meant to fly. Though it has been done before.

And rockets are not meant to be cars, at least not cars driving on public roads.

[lobsterbark]

Ok, I stated a random observation, not even a question, and accidentally started a flying cars thread.

[Warscribe]

does this even count as derail?