QUICKIE FOR TWO
- Category: Magazine Articles
- Published: Saturday, 16 October 2010 02:12
- Written by Bill Cox
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A very unconventional airplane that's possibly the most efficient gasoline-powered design ever built.
by Bill Cox - From HomeBuilt Aircraft August 1982 p. 76
If you set out to design the world's most unusual flying machine, you'd be hard pressed to come up with anything wilder than the Quickie. From any angle, it's a most unconventional airplane. Burt Rutan does not design conventional machines. When he introduced the Vari-Viggen in the early 1970s, it was virtually one-of-a-kind among homebuilts. So it is with the Quickie today.
For those who may have been living on the dark side of the moon for the last few years and haven't heard, the Quickie is very likely the most efficient, gasoline-powered airplane ever built. That's right, THE MOST EFFICIENT. We're not talking about ultralights here, though few of them come close to the Quickie's efficiency. At economy cruise, the Quickie can score an unbelievable 104 statute mpg, and at 100 mph, the miles per gallon drops only to 85. Push everything up to max cruise around 130 mph, and you'll still see 60 mpg or more.
If there was anyone who didn't believe how good Quickies are at converting gasoline to distance, last year's CAFE 250 efficiency competition at Santa Rosa, California proved the point. The Quickies present swept the field in pure mileage.
Some of the tradeoffs necessary to achieve such excellent economy are a very low frontal area, low gross weight and minimum horsepower. The Quickie uses a 22-hp Onan industrial engine to lift a maximum of 520 pounds, at least 240 of which is the airplane itself. While a 232-pound payload is impressive for this class of machine (the Quickie also carries 48 pounds of fuel), it doesn't allow for hauling more than one soul and some very small baggage. The Quickie is definitely a sport airplane, designed for the sport who likes to take his leisure alone.
Enter the Q2. When Tom Jewett and Gene Sheehan, a pair of aerospace engineers who'd worked on such programs as the B-1 and F-111, started Quickie Aircraft in Mojave, California in 1978 to market the single-seat Quickie, they were already thinking ahead to a two-place machine.
Canadian Quickie distributor Garry LeGare had been thinking along the same lines, and undertook construction of the prototype Q2 in early 1980. It was perhaps inevitable that the end result would employ the configuration of the original design, though in truth, the Q2 is a totally different airplane with very little in common with the Quickie.
One of the most significant changes is to the powerplant. The Q2 utilizes a 2100cc Revmaster Volkswagen conversion that delivers 64 hp at 3200 rpm, nearly three times the power of the Quickie's Onan (a good power-to-weight tradeoff, considering that the 150-pound Revmaster is only about twice as heavy). To feed the larger engine, fuel capacity had to be increased from the miniature, eight-gallon tank used in the single-place airplane. Accordingly, the Q2 sports a six-gallon header tank that gravity feeds into the engine and a 14-gallon seat tank, the contents of which must be pumped by an electric fuel pump into the header for use.
In order to carry two folks side by side, the Q2's cockpit has been widened from the Quickie's 22 inches to 44 inches. Total wing area has increased as well,
from 53 to 67 sq.ft., and the new airplane is two feet longer than the original. In total, the Q2 is about the minimum size airplane you could imagine capable of transporting two full-grown humans.
My opportunity to fly the newest product from Jewett, Sheehan and LeGare came on one of Mojave's typically windy May days. The temperature was a balmy 82 degrees, but the breeze was gusting to 25 knots as we rolled the airplane out of Quickie's hangar. Tom Jewett, my demo pilot for this flight, seemed fairly unconcerned about the wind. As I was to find out later, the Q2's extremely low CG and wide gear stance imparts a ground stability uncommon among 1000-pound airplanes.
Despite the airplane's Star Wars appearance, preflight is relatively conventional. There should be one wing and one canard/landing gear on each side, and the prop should be mounted out front. Jewett did emphasize a few points, however. One is that the Q2 utilizes low drag rather than high horsepower to achieve its performance. The Q2's equivalent flat plate area is 1.18, less than half that of the Mooney 201, general aviation's most efficient production airplane. Put another way, the Q2's drag is about the same as that of the landing gear on a Skyhawk. Because of this, anything that degrades lift on the leading edge of the airfoils (bugs, dirt, etc.) can result in significant speed losses, as much as five knots.
When properly constructed, the Q2 should be fairly immune from fiberglass cracks, but Jewett cautioned that builders should avoid using paints that flex with the material because they tend to hide imperfections in the fiberglass. As you might expect, construction on the demonstrator I flew was near perfect, and there were no cracks to be seen anywhere.
The Q2's plexiglass canopy is hinged on the right, so the right seat occupant climbs aboard first. From the outside looking in, the Q2's semi-reclining seating arrangement doesn't look very comfortable, but it is (a good thing, since maximum endurance is on the order of eight hours). The pilot's and copilot's feet fit up into a well beneath the panel that's higher than the seat bottom. With Tom and I fitted into the Q2, we had as much shoulder room as in a 172, and he told me how the seating position had been designed with a pair of 250-pound, 6 ft. 8 in. aviators in mind. Bear in mind, however, that you could only carry four gallons of fuel with such a cabin payload — enough for 45 minutes plus reserve.
The demonstrator had been fully fueled prior to my arrival, so total ramp weight before Tom and I climbed aboard was 645 pounds. We added 350 pounds of people to bring the Q2 to within five pounds of gross. If weight in the seats was less, up to 40 pounds of baggage could be carried in the four cu.ft. baggage compartment.
Engine start is reminiscent of a Mooney 201 or Piper Arrow. Prime is with the mixture forward for a few seconds; then, the mixture comes back to idle cutoff during initial cranking. When the engine fires, mixture goes full forward. The Revmaster settles into a comfortable 1500 rpm idle that's high enough to keep things smooth, yet low enough not to move the airplane involuntarily. Both brakes are applied evenly by a handbrake set against the left sidewall rather than the more conventional toebrakes.
The wide gear assures good control on the ground, though it's important to remember that the Q2 is a taildragger and is therefore subject to the old ad-dage about the flight not being over until the airplane is tied down. Rudder pedal sensitivity on the ground is excellent, and very quick. Yet, despite the airplane's light weight, it goes pretty much where you point it without the need for constant correction.
CIGAR (acronymese for Controls, Instruments, Gas, Attitude, Runup) works perfectly for the pre-takeoff check. Unlike the Quickie's Onan that makes do with a single ignition, the R2100 Revmaster mill employs dual mags which must be checked before takeoff, along with carb heat. Trim is a small wheel mounted fore-to-aft in the center console ahead of the side stick. The pilot can set the proper attitude with his right forefinger, trim pressures are so light.
Density altitude at Mojave's 2800-foot elevation worked out to nearly 5000 feet by the time we were ready to launch, but the Q2 barely knew the difference. Without a VSI, I had to time the climb and discovered that our initial effort was about 600 fpm, not bad at all at full gross in moderately choppy air. Quickie lists service ceiling as 15,000 feet, which is a believable number in view of the airplane's performance at lower altitudes.
A pair of airline-style eyeball vents provide plenty of fresh air in flight. With so much plexiglass everywhere you look, visibility is fairly good, except straight ahead and straight back. If I'd used a cushion, I could probably have seen better across the panel, but the wing is mounted right at eye-level directly behind you, so there's not much of a view to the aft quadrant.
Because of the physical similarity between the two-place and the single-holer, I wondered if the new airplane was as fast as the old. It is, and then some. Speed is, after all, the derivative of the Quickie name, and Quickie 2 is a very appropriate name. Tom and I tried some cruise checks at 5000 feet, but the chop was so severe that it was difficult to stabilize cruise speed.
For that reason we eventually leveled at 7500 feet where OAT was 14 degrees. That meant density altitude was almost 9000 feet, well above the optimum 75 percent altitude. Without a blower up front, full power was probably down to 65 percent; yet speed settled on 140 mph indicated for 160 mph true.
Given the Q2's ridiculously low flat plate area and minimal drag coefficient, any reduction of power below optimum causes a greater speed loss than it might on an aerodynamically dirtier airplane where power changes produce little speed change. Because we were down to 65-70 percent for our speed checks, I'd guess max cruise in smooth air at optimum altitude as 165-170 mph.
Interestingly, Quickie's performance chart for the airplane, using a mid-cruise weight of 870 pounds, shows max cruise at 8000 feet to be 170 mph. We were 1000 feet higher (in density) and perhaps 100 pounds heavier, and that's probably as good an excuse as any for being 10 mph slow. Remember that at high cruise the Q2 burns only about 3.7 gph, so it's definitely a cheap way to cover ground in a hurry.
The name "Quickie 2" could as easily be applied to control response as cruise speed. The side stick responds immediately to roll and pitch pressures without the need to move more than your wrist. Roll rate is very quick, especially to the right. The Revmaster rotates to the left, so torque is to the right, and on an airplane as small as this it makes a definite difference which direction you turn. I'd guess roll rate to the right is 90 degrees per second, while full left deflection of the wrist-activated side stick produces about half that. Elevators and rudder are similarly sensitive. The rudder is so quick, in fact, that I'd bet you could do rudder rolls in the airplane.
The folks at Quickie aren't enthused about pilots doing aerobatics in their airplanes, but it's still comforting to know that the foam/fiberglass method of construction can result in amazing strength at very light weight. The wing has been designed to withstand 12 G's, while the canard, which also contains the main gear, was built to take a 30 G load. To make things a little easier to understand and minimize confusion over the Q2's actual stress limits, Tom Jewett set the airframe limit at 4.4 G's, a figure that corresponds to the utility class in certified production aircraft.
Throughout the flight envelope adverse yaw is virtually non-existent. The ailerons are mounted well inboard on the wing, thereby minimizing coordination during turns. You can slap the Quickie back and forth, left and right, to 60 degrees of bank with your feet off the rudder bar, and there's no tendency for the airplane to sashay sloppily sideways.
Stalls are about as docile as possible. Pull the power and slow the Q2 to its' bottom speed limit, and it will simply buck up and down. The canard and wing are set at different angles of attack so that when the canard is stalled, the wing isn't. This means the airplane retains excellent roll control in the stall without any tendency to pitch down. Hold the stick full back with the power off, and the Q2 will merely settle earthward at 700-800 fpm.
Such manners pay off in the pattern where the lack of a stall makes you feel at least a little invulnerable. The side stick is designed to increase pressure as speed decreases, and there's no way to trim out the additional force, but it's not significant in any case.
The Q2 does have one major drawback around the patch, however — poor forward visibility, a characteristic shared with many other homebuilts and production airplanes. During the approach at 90-95 mph, you're pretty much blind straight ahead. If I owned a Q2 I'd fly it like a Pitts in the pattern, making a curved final to avoid losing sight of the touchdown point until the last possible moment.
The flare and landing themselves are anticlimatic. Because of the gear geometry, the current airplane is difficult to accidentally dump onto its nose, though that wasn't the case with the earlier machine. If you really pulled on the brake handle you could certainly nose the Q2 over, but you'd have to work at it.
As this is written, there are about 12 Q2s flying and another 740 kits are either delivered or on order. If you don't buy all the options, but purchase the most complete package of plans and materials, you're looking at an investment of about $10,295 and 750 to 1000 hours in time.
The engine is the largest part of the package, in dollars if not in homebuilt labor. For that reason, some builders are considering alternatives such as the 65 and 85-hp Continentals that powered Cubs and Champs. The Q2 will accept those engines, as well as others. There's a turbo version of the Revmaster available that should boost cruise to well over 220 mph at high altitude. One builder is even examining a 115-hp, 0-235 Lycoming to drive his Q2.
Whichever engine you choose, you can be fairly certain that economy and performance will be spectacular for the horsepower. Quickie Aircraft's phenomenal little Q2 is the embodiment of homebuilt efficiency and the most airplane for the least money, if you're willing to build it yourself.