Speed and horsepower don't make very good bedfellows. While it's true more power will increase speed, the trade-off is grossly disproportionate. Forget the math—it takes an exponential amount of power to improve cruise enough to notice. Ask Lyle Shelton, owner of Rare Bear, the Unlimited Class racing F8F Bearcat that's won the Reno event a half-dozen times. Shelton runs a Wright R3350 engine pumped up to an estimated 4,000 hp in place of the standard P&W R2800, rated for 2,100 hp. Shelton learned early on that, despite the huge horsepower increase, his fighter would need major aerodynamic improvements to become a consistent winner.
Unfortunately, adding power puts you into a vicious cycle. More power means higher fuel burn, which usually means increased fuel capacity and less payload, so you need to increase gross to maintain payload. Higher gross means less speed, so you need to increase power again, which means higher fuel burn...you get the idea.
Improving an airplane's aerodynamics is a more efficient method of increasing the knot count. Though reducing drag is more technically challenging than merely bolting in a bigger engine, a drag reduction is far more effective and economical. Back in the '40s, one formula that helped define ultimate aerodynamic efficiency among general-aviation aircraft was one mph per horsepower. An airplane was considered to be extremely efficient if its top speed in mph equaled its horsepower.
While that was really no big trick in the lower horsepower regime, it became progressively more difficult as horsepower, weight and aircraft size increased. Of all the general-aviation marquees competing for the four-place aircraft buyer, Mooney has perhaps come closest to the one-for-one ideal. From Al Mooney's 1950s vintage, single-seat Mite to the comfortable four-seaters of the '80s, Mooney has always been among the most efficient of general-aviation designs.
The Mooney 252 TSE (Turbo Special Edition) was especially notable, as it delivered nearly one knot per horsepower, specifically 200 knots on only 210 hp. Such brisk performance did demand a turbocharger and intercooler plus a climb to FL250, but there was nothing else in the class that even came close.
The 252 benefitted from a few other improvements in addition to turbocharging and intercooling. The gear was fully enclosed (all previous Mooneys left the inboard portion of the wheels exposed), the window line was rounded for a more modern look, the electrical system was updated to 28 volts and a set of enlarged cowl flaps used electric power for infinite adjustment.
In addition, the 252 incorporated upturned, high-lift wingtips, complete with forward facing recognition lights and aft-facing position lights. Finally, Mooney increased gear extension speed from 132 to 140 knots and flap extension for the first 15 degrees to 132 knots. (Limit speed once the wheels were down and locked was a quick 165 knots.)
Why not, someone reasoned, incorporate all the 252's aerodynamic and convenience improvements into the normally aspirated 201? Mooney did exactly that in 1987 and created the Mooney 205, theoretically blessed with a 205 mph top speed.
Theoretically. Top speed is a fairly nonsensical PR ploy, anyway, as no sensible pilot runs his airplane flat out at sea level, at least not for long (especially if he wants to keep his license). In fact, just as most 201s were incapable of reaching a 201 mph top speed, few 205s could touch 205 mph. No matter. With a drag coefficient of only .0173, there was little question the 205 was the slickest, normally aspirated production airplane in the sky.
Perhaps the best comparative measure of drag is equivalent flat plate area, the total drag of an aircraft expressed as if it was a flat plate being pushed through the sky. As a point of reference, a relatively draggy Great Lakes biplane has an equivalent flat plate area of 11.5 square feet. In contrast, both the V35 and F33 Bonanzas score 4.6 square feet. The Mooney 201 and 205 share an equivalent flat plate area (efpa) of only 3.6 square feet.
Apparently, however, an extremely low drag coefficient and minimal efpa are no guarantee of success in a fickle marketplace. The timing was all wrong on the 205. The airplane premiered in 1987 when the general-aviation industry was slowly spiraling toward the black hole of the early 1990s. As a result, the 205 lasted only two years and sold a mere 77 examples.
FAA records suggest that fully 71 of those airplanes are still flying, and the folks who own them are happy pilots indeed. The Summer 2003 edition of the Aircraft Bluebook Price Digest suggests that a typical 1987 Mooney 205 flew away from its Kerrville, Texas, factory at a tab of $149,440. Today, the same airplane demands $125,000, so the 205 would seem to be a fairly good value...if you can find one.
One happy Mooney 205 owner is Doug Moreland of Mt. Pleasant, S.C. Moreland is the third owner of his 205, an '87 model designated N205CC, and though the airplane remains essentially stock, Moreland has made a few changes. A Garmin 430 now graces the panel, as well as a WX-900 Stormscope and an HSI.
Cockpit and panel layout of the 205 is virtually identical to that of the 201, compact without being tight. Contrary to the Mooney cockpit's image as a tight enclosure, it's actually as wide as a Skylane's and nearly as tall. Part of the problem is that pilot and copilot must fit their legs into tunnels separated by the nosegear well, so lateral legroom is limited.
At least panel layout is exceptional. Some pilots feel a little claustrophobic because the panel is so close, but I find it just right. All system controls fall readily to hand, and even short folks can reach everything up front without stretching.
With its characteristically heavy load of equipment, Moreland's airplane weighs in at a hefty 1,785 pounds against the aforementioned gross weight of 2,740 pounds. That leaves 955 useful pounds, but only 571 pounds of payload after filling the 64-gallon tanks. Fortunately, the owner most often flies his Mooney with only two folks up front, Moreland and his wife (also an enthusiastic pilot), though he has on occasion loaded the airplane with four full-sized adults, downloading fuel appropriately. With only two up front, Moreland can carry all the baggage he can stuff aboard without exceeding gross weight.
None of the 200-hp Mooneys exactly scamper down the runway at power-up, a simple function of power-to-weight ratio. With a max gross weight of 2,740 pounds, both the 201 and 205 share a power loading near 14 lbs./hp, so don't expect to get back-stabbing acceleration when the throttle hits the stop.
Once the airplane lifts off, cleans up and starts uphill, however, you can plan on an easy 1,000 fpm for the first few thousand feet. Prior to introduction of the big horse Mooneys (the TLS in 1989 and the Ovation in 1994), the airplanes weren't famous for high climb rates, but what climb there was seemed to go on forever, lofting the type to 18,000 feet or higher. That's partially a function of the airplane's fully flush-riveted, high dihedral (5.5 degrees), slightly forward swept wing.
In Moreland's airplane, optimum cruise height of 8,000 feet comes up in about 10 minutes. The owner suggests his airplane is an honest 166- to 167-knot machine at max cruise under perfect conditions. That makes it a knot or two quicker than a typical Mooney 201 but not quite up to the book spec of 171 knots.
"The 205 may be a little faster than the 201, but the major benefit is esthetic," says Moreland. "The improved window line gives the airplane a more modern look, and the full gear doors, though obviously invisible from the cockpit, slick up the belly, probably worth a knot or two. Overall, though, we certainly haven't been disappointed in the airplane's performance. We regularly block it at 160 knots TAS, and our experience suggests that's a fairly reasonable number, especially on long trips after you burn down to a lighter weight."
The Mooney 205's Lycoming engine is a relatively efficient powerplant, rated at a specific fuel consumption of .42 lbs./hp/hr. Do the math and 75% power comes out to about 10.5 gph. The Mooney factory specifies a conservative 10.8 gph and Moreland suggests that spec is right on.
With such efficiency available, hardly anyone cruises at less than 75%. At that power and optimum altitude, Moreland can plan on 14.5 nmpg, almost 17 smpg, nearly as good as a typical Mercedes and at least three times faster (except on the German autobahns). "The nice thing if you need to extend range," comments Moreland, "is that you can come back to 65%, reduce fuel burn below 10 gph and only lose about five knots of speed. That means you can easily range out almost 800 nm without stretching fuel reserves too far."
If you feel the need for even better range, Jose Monroy of Monroy Aero in Fort Lauderdale, Fla., offers 30-gallon aux tanks that add nearly 500 nm to the basic Mooney's reach, boosting the airplane's total range to well over 1,200 nm. Fly eastbound in the lower 48 and you could travel coast-to-coast with only one stop.
The joy of Mooneys isn't confined to pure speed and efficiency, however. Though the airplane isn't as quick-handling as a Bonanza, it uses rods instead of cables for roll control. That imparts a very solid, direct feel to the ailerons and elevator, with no slop at all waiting for loose cables to tension and pull. Roll rate definitely isn't the quickest of any production single, but controls are so positive, response seems quicker than it is. This helps make Mooneys popular machines in IFR conditions, where the airplanes' response strikes just the right balance between twitchy and not sensitive enough. (I know one now-retired Mooney dealer who used to fly loops, rolls and hammerheads on a regular basis. Mooneys are only certified for normal-category maneuvers, but the airplane is easily strong enough for inside acro. No, that doesn't mean you should run right out and try vertical and inverted tricks in your Mooney.)
With so little drag, the 205 comes downhill with a vengeance. That's one reason Moreland's airplane features optional speed brakes that swivel up out of the aft wing, just ahead of the flaps. You can deploy them right up to redline without any problem and they have a dramatic effect on speed/altitude.
The Mooney's short chord flaps span fully 70% of the wing trailing edge, and the result is a major reduction in stall speed, eight knots. Better still, full flaps pitch the nose down and dramatically improve the view forward. With the resulting dirty stall of 55 knots, approaches can be as slow as 70 knots, but most pilots prefer at least 75 knots. IFR approaches work well at 90 knots, even 80 if you're familiar with the airplane.
Don't believe everything you read about infamous Mooney landing characteristics. The airplane isn't the floater it's alleged to be. It's true the wing may try to fly longer than you'd like, but with the help of speed brakes and a full flap slip, you can slough off the speed fairly quickly. If there's one common landing problem, it's probably that the airplane sits low on its rubber doughnut gear. It may take a little more practice to recognize proper gear height, but most new Mooney pilots are comfortable in the airplane after a few hours of landings.
As the ultimate development of the four-cylinder Mooneys, the Mooney 205 probably deserved a better fate than a mere two years of production. Many Mooneyphiles insist the later, four- cylinder 201s/205s were by far the best general-aviation singles ever built. Of course, I know some pilots who'd disagree. They fly Bonanzas/Centurions/Swifts/Comanches....
According: planeandpilotmag.com
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