Firebird III, an extravagantly finned, double-canopied gas-turbine car, is introduced this week by General Motors. It has as much shock value as any car ever built—"the car which a person may drive to the launching site of a rocket to the moon," as Chief Stylist Harley J. Earl put it. In its styling the Third Bird, 37th in Earl's procession of GM dream cars since 1936, is frankly inspired by the work of the missile men, and its shape is futuristic indeed. But the real news is beneath that silver-, pearl- and gold-tinted plastic skin:
1) A unique driver-control system featuring a single stick which eliminates the conventional steering wheel, brake pedal and accelerator pedal.
2) An electronic guidance system which, on an appropriately rigged roadway, permits hands-off driving.
3) An improved version of GM's regenerative gas-turbine engine, mounted in the rear.
4) A "Little Joe" two-cylinder, 10-hp, front-mounted gasoline auxiliary engine, which provides the power for all accessories.
5) A 110-volt generator which can be used to provide household current in case of storm damage or crippling enemy attack.
6) A remote control system by which the double-bubble canopies over the "passenger capsule" can be opened from some distance away. A sonic "key" carried by the operator sends out a high frequency note to a microphone in the car, which actuates the door-opening mechanisms.
7) Contour seats which represent an enormous advance over Detroit's conventional showroom-bounce bench seats. GM stylists said the usual bench seats may permit a buildup of as much as 70 pounds of pressure per square inch on the backside; this is what causes the urge to squirm on a long trip. The new seats, which, incidentally, would go over big on a suburban lawn, are designed to limit maximum pressure to three pounds per square inch.
These are not all the goodies on Firebird III, by any means, but they are the most important. The most revolutionary and dramatic single feature is undoubtedly the single stick control. The dozen journalists who attended a preview of the car the other day at General Motors' Desert Proving Ground near Phoenix first rode in it, then tried out the single stick business on a Chevrolet convertible. Wow!
To begin with, the Chevy had no steering wheel or steering column—an obvious safety advantage in case of panic stops which throw the driver forward. The control stick was just forward of the driver's armrest. You grasped the knob at the top of the stick gently with the left hand, pushed forward on the stick, and the car accelerated straight ahead. You pushed the stick to the right and the car turned right. You pushed the stick to the left and the car turned left. You hauled back on the stick, and the brakes were on.
The stick had none of the "play" of the conventional Detroit steering wheel. It translated the smallest motion into action at the wheels, and a steady hand was needed to keep the car from zigzagging at low speeds. Any degree of play can be put into the system, however, and a slower response would be better for beginners. Sensitive as it was on the Chevy, the system was fairly easy to control after a few minutes' experimenting. It was a singularly exhilarating experience. On Firebird III the stick is mounted between the seats. As on the Chevy only hand pressure (and not very much of that) is required; the forearm rests on a ledge behind the stick. If the stick's handrest is turned 20° to the right or left the car is in reverse, but the stick functions as before.
That is how it works. Why it does 50 is a bit more complicated. Here is what GM says (best taken with aspirin and a little water):
"Having complete freedom of motion with a four-inch sweep, the stick can produce any possible combination of driving operations. It does this by positioning either or both of two electrical potentiometers attached to its base. One...feeds a voltage to an electronic analog computer in the steering system, the other to an electronic system which controls the throttle and brakes.
"The principle of operation is essentially the same for each control channel: for example, the steering system computer receives a signal from the hand control potentiometer, another from a tachometer generator showing car velocity, and a third from an indicator showing front wheel position. From these three signals it computes a stabilizing signal that it flashes to an electrohydraulic control valve on the front wheel servomechanism. This valve regulates the flow of high pressure oil to a power piston that turns the front wheels. The throttle and brakes are similarly controlled by individual computers and servomechanisms."
Check. We now go on to the hands-off guidance system. Given a roadway with a special electrical cable embedded in it, the car is so equipped electronically that it will travel directly above the cable with no steering from within. The driver may accelerate or brake as he desires. Or, by pressing a button, he may order the car to maintain a constant speed.
It is, then, a very clever car, and it has two very interesting engines. The 225-hp gas-turbine engine is asked only to turn the rear wheels. In operation its gear noise is like the sound of a jet-prop Viscount airplane—a rather piercing whine. It is smaller, simpler, lighter, more economical and more powerful than its predecessor on the Firebird II of 1955. It is not expected to replace the piston engine on passenger cars any time soon, but it may be used on trucks before long. Theoretically, it can move the very heavy (5,275 pounds) Firebird III at a maximum speed of 150 mph. About 90% of the exhaust heat is recovered and used to preheat incoming air (the "gas" of the gas turbine), and this recovery system is what makes the car roadable in ordinary traffic. A straight exhaust system would scorch anything in its way, because the temperature in the combustion chamber goes as high as 1650° F.—hot enough to melt silver.
A WASTEFUL SYSTEM
Of more immediate interest than the turbine engine, however, is the Little Joe engine, because of its obvious possibilities for conventional cars. The multitude of power accessories on today's cars must be able to operate at the standard engine's idling speed, an inherently wasteful system. Little Joes would permit as much driving oomph from much smaller engines and would operate the power accessories at a constant, efficient speed.
The Firebird's Little Joe is a 20-cubic-inch, four-cycle, opposed-piston, 53-pound aluminum engine (the first without liners), with a 2½-inch bore and 2-inch stroke, developing its 10 hp at 3,600 rpm. It can be time-set by the driver against his return, by the way, to warm or cool the car to a comfortable temperature via heater or air conditioner.
Other innovations from the labs of GM's research chief, Lawrence R. Hafstad, who was responsible for the technical side of Firebird III, cannot be dealt with at length here. Not to be overlooked, though, are the light-sensitive electronic system which turns driving lights on and off as required; a very advanced air-oil suspension and car-leveling system; a unique wheel-braking system in which the aluminum drums are cast as integral units with the wheels; and air-brake flaps at the rear which are reminiscent of those used on the Mercedes 300SLR racing cars at Le Mans in 1955.
The question naturally comes: When will these things go into production? Put to Harley Earl and Larry Hafstad by the newsmen at the Arizona proving ground, the question produced only a little lecture against crowding them on the subject of practical applications.
Well, at any rate, Firebird III is startingly real. It works. It has, as one stylist said, a lot of Barnum in it for show crowds (the car will be featured at GM's Motorama, starting October 16 in New York), but it has enough solid new engineering beneath its bubble top to keep car buffs chewing on it for years.