Electric Planes Turn Up the Juice

Until recently, many viewed electric powered aircraft as being solely in the realm of tinkering home builders tucked away in their garage with little chance of actually flying - and if they did, quickly melting into a plastic glob. However, a number of well built and airworthy eclectic prototypes on display at AirVentue 2009 demonstrated that the technology works and is maturing quickly. Lead by the Chinese-built Yuneec E430, which can fly two people for roughly two hours at 60 mph on a full charge using a 40 KW (or 54 HP) motor, builders think the next 10 years will be genesis of the mass produced electric airplane. While experts say battery capacity needs to double from today’s best options to make the e-powered planes competitive with pistons, the rising cost of fuel and almost zero engine maintenance will make them increasing viable in the coming years.

Because Fido Deserves Better

The days of being forced to travel in the cargo hold or crammed underneath the seat while traveling across the US may be a thing of the past for today’s pampered pets. Florida-based start-up Pet Airways shuttles pets of all sizes sans annoying human owners, using Beech 1900 aircraft between hubs in New York, Baltimore, Chicago, Denver and Los Angeles. Enjoying main cabin comforts including frequent potty breaks and treats, Pet Airway’s pawsengers can expect to pay roughly $300 for a one way ticket between New York and LA - only slightly more than what it would cost to travel cargo with the majors.

Behold the Battle Birds

Similar to an alien virus, unmanned aerial vehicles (UAVs) of all sizes seem to be evolving faster than humans can come up with cool-sounding names. California-based AeroViorment, maker of several RC airplane-sized UAVs used by the US military, recently showed off its first DARPA funded Nano Air Vehicle (NAV), which happens to look and fly just like a humming bird. The goal is to create tiny surveillance aircraft that behave like actual hummingbirds while sending images back to nearby troops or perhaps delivering a poisoned peck to the eye. Via battery-powered flapping wings, AeroViormet’s NAV can hover and fly in all directions under remote control - autonomous versions are also in the works.

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PilotMag introduces our PRODUCT REVIEW department with the intention of providing un-biased and practical reviews of great, aviation related products to our readers. We decided to include genuine and honest product reviews, starting with this issue, that readers could rely on and those that weren’t a blatant attempt to appease our advertisers. We have been on the lookout for unique, high-quality products that have a useful and affective use in our everyday, general aviation lives. One of the best places to see all these new and interesting products is EAA’s Oshkosh AirVenture show every year. We were able to explore all the different exhibits and see a plethora of the latest general aviation gadgets and technology. So many that it would take volumes to show them all.(Check out PilotMag’s Gadgets and Gear Guide in our November/December 2009 Issue) Unfortunately, we only have space to highlight just a few in this issue, so we hope to show a diverse collection of new and cool products that our readers would enjoy learning about.

Aero Tow’s Lil Sherman

In the category of smaller tugs that won’t break the bank, but are still high-quality work horses, I found one tug that was made by a company out of Lake Mills, Wisconsin called Aero-Tow. I was very impressed with Aero Tow’s three different battery powered tugs that are unusually affordable and work great. I especially liked Aero Tow’s Lil Sherman aircraft mover designed to allow one person to easily move a single or twin airplane. Adaptors are available on the Lil Sherman for a wide range of aircrafts and can be attached to either the nose wheel or tail wheel. Additional adaptors are also available that enable attachment to aircraft with wheel fairings. The swivel front frame of the Lil Sherman compensates for forward cantor of the nose wheel of most aircraft while turning and positioning. This keeps the wheels of the tug on the round for better traction and protects the gear from any damage. The Lil Sherman is powered by a three-horsepower, 24-volt electric drivetrain moving an aircraft in upwards of 6,000 pounds. The unit is equipped with 2 – 12 volt batteries and an automatic battery charger. It also has lights that help illuminate during evening ground handling or precision with positioning the unit. The Lil Sherman is also a breeze to assemble consisting of only ONE bolt.

The TugBot

Another category of tugs that I found interesting was a new, remote-control tug. These tugs are battery operated and work with a hands-free remote control, similar to those used for RC aircraft and kids toys. There were a couple manufacturers of these tugs in Oshkosh, and they all had their unique designs and interesting features. The one that stood out was made by a company called TugBot. This tug was designed and developed to meet many practical ground handling needs of pilots, FBO operators and maintenance operations needing to manage large single and twin engine aircraft weighing from 3,000 to 15,000 pounds. Built like a tank, the TugBot is generally used for retractable gear planes, but will also work well with any plane that has the front wheel pant removed. The TugBot securely maintains control minimizing any risk of a runaway aircraft. This unit is an all electric vehicle with an optional 24DVC APU unit, perfect for ground starts, and its unique design allows it to be operated on a variety of surfaces while maintaining traction with an extremely precise and gentle maneuvering capability.

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Ground Effect Vehicles Play Catch Up

An elegant blend of aircraft, riding mower and ceiling fan, the hovercraft was once heralded as a world-changing technology that would alter the way we all traveled. Images of happy families buzzing around over smooth states of earth and water in their floating station wagons were featured in publications like Popular Science from the late 1950s to early 60s. Along with flying cars and rocket packs, the once promising hovercraft remains an underachieving technology, 60 years after its birth relegated to the back row by practical, technological and operational challenges. In a recent push of technology to combine a ground effect vehicle, such as the hovercraft, with a fixed-wing, flying aircraft is creating some interesting contraptions that are a wonder to behold, yet potentially practical.

A Skirt, High Pressure Air and Ducted Fans

Developed in the mid 1950s by an English knight, Sir Christopher Cockerell, the hovercraft, enclosed by a skirt, sits on a cushion of high-pressure air and is propelled by props or ducted fans on its topsides. More specifically, modern hovercraft force air into a channel or plenum chamber around the outside of the vehicle’s skirt that creates a blast of ducted air pointed towards the center of the craft. The addition of numerous air filled “fingers” to the plenum allow the hovercraft to move over small obstacles with minimal disruption. Hovercraft are great for moving across water, ice, snow, and other flat smooth surfaces such as beaches. They are not so great for going uphill or hovering over obstacles greater than a foot or two in height or moving over sloped terrain. Sitting on a nearly frictionless cushion of air, the hovercraft will always slide to lower terrain and thus these awe-inspiring vehicles have been limited to terrain that’s too soft for wheels or too shallow for boats, such as mud flats, river deltas, or swamps. The frictionless cushion of air also makes hovercraft difficult to accurately pilot. There are no brakes, and that can be a problem. Hovercraft pilots control speed via prop RPM and steer using moveable rudders mounted behind the prop, much like an airboat. Easily scalable by sowing a bigger skirt on the craft and adding more air, the hovercraft can be used in a variety of different missions. The British used hovercraft to provide high speed ferry service between England’s southern shore and northern France. The massive vehicles carried over 400 people and 60 cars while reaching top speeds of 50 knots. I was lucky enough as a young boy living in England to take several of these rides across the channel. The exhilaration of being lifted ten feet into the air as the massive turbines fired up, forcing air into the hover skirt was only matched by the slight fear of hurtling towards a beach with no intent of slowing down. The channel-hopping hovercraft saw their last day of service in October of 2000 as high fuel prices and the newly built channel-tunnel conspired to render them obsolete.

A Wing in Constant Ground Effect

While not necessarily a new technology or one that has found much popularity, a WIG craft, an Ultra Large Transport Aircraft or wingships in modern parlance have evolved on the fringes of aviation for the past 50 years. The idea is simple: by keeping a wing in ground effect (see Aerodynamics on Page 31), the power required to fly is reduced over that of a traditional aircraft or hovercraft. The Russians went WIG crazy in the mid-sixties. Their Star Wars-themed Ekranoplans was built to position missiles at high speeds underneath radar detection. WIG technology allowed the planes to carry huge payloads with minimal wing structure. The once famous “Caspian Sea Monster” weighed over 550 tons, was 300 feet long and could reach speeds of 300 knots at heights of 20 meters off the water. When not in ground effect flight, the Ekranoplans acted like regular ocean-bound ships slowing plying through the water but ready to go airborne at a moment’s notice. The Russians tinkered with militarized wingships through the 1980s but as the Cold War ended and funding ran out the technology was left to wilt.Inspired by the early Ekrnaoplans, a number of smaller civilian purposed WIG craft have popped up over the years; the Australian Flarecraft, the FS8 Dragon Commuter, the Amphistar, the Weberwing. Some have flown quite well, others not so much. Built in small batches and never fully developing past the prototype stages these wingships, along with dozens of others, ably demonstrated the concept of combining a hovercraft, a boat and an airplane. But the right amount of each has so far evaded developers.

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Better Engines through Racing

Air racing is the proving ground for air-cooled aircraft innovations. Consider this:In 1947 the Professional Racing Pilots Association formed rules for "midget" racing. The goal was to reduce the cost of air racing. Goodyear Tire and Rubber provided sponsorship and just seven months later 13 airplanes crossed the starting line in Cleveland for the inaugural race, which was won by pilot William Brennand in "Buster," a Steve Wittman design. The winning speed was 165.9 mph. Initially midget racing engines were limited to 190 cubic inches. Continental's C- 85 engine fit the bill but after a couple of decades serviceable components-especially crankshafts—became as scarce as an NDB approach. In mid-1968 the F1 ruling body OK’ed the use of the affordable and plentiful Teledyne Continental Motors (TCM) O-200 engine. This engine is best known for powering Cessna's C-150 trainer. It's rated for 100 horsepower at 2750 rpm. At about that time the class was officially recognized and renamed Formula 1. F1 rules spell out wing size, minimum aircraft weight, minimum fuel quantity and other parameters but in spite of these constants the fact remains—in 1996 the qualifying speeds at the Reno F1 race were over 100 mph faster than the speed of the top qualifier in 1947 on an engine that has only 5 percent more displacement.

Improvements in airframe construction methodologies and materials have made a huge difference in reducing drag but the following sentence sums up the gist of F1 engine improvements:"Since an aircraft engine is nothing more than an air pump the efficiency at which an engine draws in and expels air determines its overall performance"--John Schwaner, "Sky Ranch Engineering Manual". Volumetric efficiency is the ratio between the theoretical amount of air drawn into the engine and the actual amount of air drawn in. A higher ratio yields more power.

F1 Racers

Formula 1 engines can be modified, but not as much as might be expected. F1 rules that aim to keep F1 racing affordable require that the weights and sizes of major power components must conform to limits and that compression ratios can't be greater than the stock number of 7.0:1. Out-of-the-pump avgas must be burned. So how do they get so much power out of an O-200? By increasing volumetric efficiency and installing specially-built propellers which free the engines to spin up to between 3800 and 4400 revolutions per minute (rpm). O-200 manufacturer TCM publishes 3300 rpm as the over-speed limitation for the O-200. Spin an O-200 installed on a certified airplane faster than 3300 rpm and you're advised to remove, tear down and inspect the engine and accessories for damage. How do F1 engine builders keep their engines together? It all boils down to the expertise of the engine builders. According to one of the builders the task of flying in close proximity to other racers at speeds of to 280 mph automatically relegates engine management chores to the basics. Push the throttle forward as far as it will go and lean to a best power mixture (70 to 80 degrees rich of peak) and try to keep up. Increases in volumetric efficiency cause dramatic increases in engine output as fuel flows increase to 14 to 15 gallons per hour—roughly twice the normal fuel flow of a stock O-200. More fuel also causes more heat--cylinder head temperatures often top 500 ° F. Are special parts used? Yes, to some degree, but it's not a free-for-all. F1 racers must use TCM factory or officially approved parts but they may change "any fit, clearance, or oil lube hole to compensate for increased heat and rpm." Higher rpms are a function of higher volumetric efficiencies.

Improving Volumetric Efficiency

Port polishing and flow porting is the practice of smoothing the inner surfaces and fine-tuning the fit between induction system components to lessen airflow discontinuities. According to Schwaner the goal is to reduce the "pressure differential that exists between the intake manifold and the cylinder during the intake stroke." Other processes used to improve efficiency are increasing intake valve size and matching lifters and camshaft lobe profiles so that all cylinders breathe evenly and produce the same power. Valve timing is sometimes advanced to compensate for the reduced valve-open periods due to higher rpms, and intake valve seat angles are fine-tuned to further reduce restrictions to air flow. A five-angle valve seat cut—instead of the three-angle cut common on FAA certified engines--increases efficiency by lessening the angles of airflow change. Visualize the flow of water down a rock-strewn creek bed and compare that to the same flow down a smooth gutter. More water can flow faster down the smooth gutter. It's that simple. With every tune, there's always a back beat. As RPM is increased volumetric efficiency decreases simply because the time window for the fuel/air charge shrinks. Research shows that the stoke time at 2400 RPM is 12 hundredths (0.012) of a second. At 3600 RPM the interval shrinks to 8 thousandths (0.008) of a second—one tenth of the time. Counter that engine operating whipsaw with the fact that increases in horsepower and RPM increase dynamic forces on mechanical components. Not only must the components be able to withstand higher loads but they must be lighter in weight to successfully compete. What steps do builders take to insure durability?

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Winch-Launched Soaring in the Swiss Alps

Even now, it seems fair to say the United States is still the least expensive, least complicated place in the world for recreational flying. But during these bad economic times, flying seems to be getting farther out of reach for more people. With that in mind, I thought one approach to the situation would be to look for a solution where recreational flying and flight training have always been more complicated and expensive. One fascinating alternative to expensive flying is winch-launched sailplane flying. It is appealing partly because it's a relatively cheap way to fly, and because it's a great way to learn. Glider pilots learn to be good students of their environment. To feel aerodynamic principals directly and see the results in a very immediate way provides an excellent base of understanding for any other kind of flying. The Air Force Academy in Colorado Springs, Colorado trains its students in gliders, and sailplanes have also been a favorite form of recreational flying among senior airline pilots. Winch-launching has always been much more popular in Europe and the UK, due partly to the historically higher cost of powered flying, and concerns about airport noise. In fact, some small European airports allow no powered aircraft, tow planes included. Of course the launch location does make a difference with winching compared to aero towing. A day with good thermals over flat land, or ridge-lift producing terrain, makes the difference between one short training circuit and soaring to record setting times, altitudes and distances.

Soaring the Alps

Recently, I had the pleasure of experiencing winch launched soaring over the Swiss Alps, from Engadin Airport in Samedan, Switzerland. During ski season here the tarmac is overcrowded with corporate and private jets, delivering their passengers to nearby alpine resorts. Because of its excellent lift producing topography and spectacular scenery, this place is also world famous among glider enthusiasts. Winching (Winderstart in German) is the standard mode of launch here, as I found during my conversation with Bruno Minder, glider flight instructor and head of Swiss Jet Ltd. Segelflugzentrum (Sailplane Center) Samedan. Minder explained that tow planes are occasionally used for special events like contests, but not on a regular basis. Swiss Jet has three beautiful, high-performance Schemp-Hirth Duo Discus sailplanes. Being a pilot of powered flying machines, I was curious about their spoilers (or speedbrakes). A necessity for glider pilots - to avoid overshooting or landing short of a runway - spoilers are unfamiliar to many light airplane pilots. I asked Minder how effective the speedbrakes are. “Normally they are built for a 45 degree emergency descent, so with full brakes and full descent, you don't exceed the VNE (the never exceed speed of 280 KPH or 173 MPH).” Speaking of “V-Speeds,” I asked about the Duo Discus' stall speed and approach speeds. Minder: “Stall speed depends on the weight, but with max takeoff weight, it's around 65 KPH (40 MPH). With 65 at normal weight, the rudder's a little weak, and it's not very stable, but it's still flying. On final approach and without any speed increments for wind (add half the headwind component), it's 90 to 100 KPH (55 to 60 MPH). When you have really strong gusts and you can't be sure if you have tailwind or headwind, then you fly quite fast. I would take 150 KPH (93 MPH), and then at the last second you reduce speed. It's quite easy to fly with that higher speed to the ground and then apply the speed brakes. With strong headwind (low groundspeed) it's no problem, with a tailwind you have to be slow, and you don't have force in steering (during the landing roll). “It's a little difficult when you have a strong tailwind,” he continues. “You land and you don't have gear (one wheel under the cabin), so you need to have the wings level with the ailerons. Otherwise it's not so nice.” I learned to fly in a very light airplane with no flaps (a Taylorcraft BC-12D) where the forward slip was an essential maneuver to control descent. So I asked Minder, “With the spoilers, do you ever slip?” “For training yeah, but it's not so necessary. Depending on the brakes you have, there are gliders with less effective brakes. The most effective way with this glider is to apply full speedbrakes, push down the nose and increase speed towards 160 KPH (100 MPH). Normally when you're too high, you dive with the speedbrakes just a little bit below the normal glidepath, then pull up and decelerate.”

Winch-Launch Can Be Tricky

There are hazards associated with winch launching. Minder explains, “There are 2 kinds of classic winch accidents: One is the high-speed stall, when the plane is pitching up too much (sometimes by over-rotation after liftoff). This is a situation where the pilot can't recover, because there is too much load factor with the rope pulling from below. The location of the rope below the center of gravity is one factor, and another is where you put the [pitch] trim. The other kind of accident is when you are very steep, and the rope breaks (power loss). Then you have to be very, very quick to push the nose down. Otherwise when you wait too long and you are too slow, you don't have any chance to recover.” Another cause of accidents is a wing touching the ground during the takeoff roll, causing a cartwheel or groundloop. One measure against this is to have a hand on the cable release early in the launch, and to release immediately if it becomes difficult to keep the wings level. It also helps to have a person running with the wingtip at the beginning of the takeoff, to hold the downwind wing in a crosswind. Before my flight, I spoke with Irene Schlachter, a helicopter student pilot from Olten, Switzerland, after her first flight in a winch launched sailplane. “First you have the impression of sitting in something really small. You don't have the feeling of being really crowded, but there's just not much around you. It's different than a motorplane or a helicopter. It's reduced to sort of a minimum, but a very high-tech minimum,” she describes.

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Aircraft Recovery: A True Art Form

Undeniably, there are certain professions and trades which require mastery; mastery only attained by countless years of hard work, study, sweat, and labor to perfect and hone a skill. Those involved in the unique world of aviation know that whether one is a pilot, mechanic, air traffic controller, accident investigator, or anything in between, mastery of the skill comes best with time and practice. In most cases, it is a labor of love. Aviation just has that way about it. One unique and little discussed facet of aviation that requires a master skill set is that of aircraft recovery—the task of recovering an aircraft that’s been involved in an incident or accident, and has often sustained enough damage to render it incapable of being flown out of its current location. Hence, the need for some of these recovery masters and the exceptional skill required to transport an ill-fated plane to its final resting place. But it isn’t just about removing wreckage from the side of a mountain or pulling it out of a marshy swamp. Because thorough post-inspection of an aircraft may be required, it must be removed in the most preserved condition possible—sometimes part by part—because of the likelihood that further post-scene analysis will be necessary.No one seems to understand that better than Eddy Schumacher, head of Air Transport and Investigations with Beegles Aircraft Service in Greeley, Colorado. Eddy began working as an Airframe and Powerplant Mechanic (A&P) back in 1991, all the while jumping at any part-time opportunity to assist on recoveries. Eight years later, he was at it full-time, and now leads both small and large teams in Beegles’ recoveries.

An Orderly Recovery is Essential

Over the past 18 years, Eddy has performed several hundred recoveries (his closest estimate was between 300 and 500), at an average of 40 to 50 per year. With a territory covering all of Colorado and midway into the bordering states of Wyoming, Utah, New Mexico, Kansas, and Nebraska—even a few in Montana—he’s on-call 24/7 and on the road about 40 weeks of the year, behind the wheel of a one ton diesel truck with a portable crane and trailer. According to Eddy, he’s notified of a pending recovery by the NTSB about 75 percent of the time, with other reports coming from insurance companies, friends, or co-workers. There have even been a few cases in which he was watching the television news, viewed coverage of an aviation accident, and suspected a phone call would be forthcoming. And, yes, his suspicions are always right. Once he receives the call, Eddy begins to coordinate equipment according to the size of the downed aircraft. Approximately 90 percent of recoveries are small general aviation types (Cessnas and Pipers), while the remaining 10 percent are either large airplanes (Citations, Challengers, Lears, etc.) or helicopters. In the case of large airplanes, he’s even had to occasionally hire larger-sized cranes while in the local recovery area. Nearly 75 percent of all recoveries he’s performed have been fairly accessible and required only one trip. More remote locations oftentimes necessitate the aid of a helicopter, with an average of four to 10 trips per recovery in those cases. No matter what size the job, he stands by until the investigators are finished with their on-scene work, meticulously ensuring that he’s received a verbal go-ahead from the NTSB that the wreckage is officially released and the recovery process can begin.”

Scattered on the Summit

It was September 2006 when the call came in. A Beech 35-C33 (Debonair) with four people onboard was on its final leg of a flight to Telluride, Colorado, when it was destroyed after impacting mountainous terrain nine miles southwest of Telluride. The flight originated in Taos, New Mexico earlier that morning and was not on a flight plan. Denver’s Air Route Traffic Control Center picked up the airplane on radar approximately 38 nautical miles northwest of Taos, heading toward Pagosa Springs, Colorado, at 15,800 feet msl. Just southeast of Pagosa Springs, the airplane turned toward the southwest. Approximately five minutes later, the airplane resumed a west-northwesterly course toward Telluride. About 25 miles south of Telluride Regional Airport (TEX), the airplane turned to the north and descended to 15,000 feet. According to the radar data, one minute later, the airplane was in a 600-foot-per-minute descent that eventually brought it down to 14,000 feet. Approximately 12 miles south of the airport, the airplane turned to the west-northwest, putting it at 13,900 feet on a course toward Wilson Peak and Lizard Head Pass. Approximately three miles southeast of Wilson Peak (elevation 14,246 feet), radar showed the airplane enter a 2,000-foot-per-minute descent. The airplane’s groundspeed increased from 149 to 260 knots. The airplane leveled off momentarily at 13,400 feet and then proceeded to enter a 2,000-foot-per-minute climb. The airplane’s groundspeed was 191 knots. Approximately 12 seconds later, radar contact was lost. At last contact, the airplane was at 13,500 feet, within one mile of the southeast face of Wilson Peak.

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Inside the Mysteries of Ground Effect

Often taken for granted and sometimes considered a nuisance for the newbie fixed-wing pilots, the phenomenon known as ground effect is more complicated than one might expect. Yet, its complimentary assistance in reducing drag and power requirements is an invaluable resource for slab and fling-wing pilots alike. In fact, there’s many a summer day in the Rocky Mountain West, with density altitudes closing in on 10,000 MSL, that we’d never get off the ground in our little piston aircraft without a big helping of ground effect. On the flip side, ground effect can lead pilots into a false sense of security, conning us to believe we have more lift and horsepower in reserve. If ground effect is more than just a cushion of air, how does it function aerodynamically? What are the many benefits of ground effect and how can it help us all fly safer? An aircraft can experience a number of different ground effects when flying in close proximity to the Earth. The most pronounced and beneficial of those effects is wing in ground effect (WIG). Most pilots are aware of the swirling vortices created at the wing’s tip by air trying to move from the high-pressure area on the wing’s underside to the lower pressure created on top. By disrupting airflow at the wing tips, these vortices are a necessary but unwanted by-product of generating lift and reducing the amount of lift a wing can produce. They also create what’s called “induced” or “downwash” drag as the spinning vortices pull the airflow over the wing downwards, similar to a flushing toilet. The lift-robbing wing-tip vortices force wings to fly at a higher angle of attack, which in turn means more drag. A heavier, higher horsepower engine is required to deal with the increased drag and lack of aerodynamic performance - and the vicious cycle continues from there. Wing designers use a number of tricks to reduce the impact wingtip vortices have on lift. Gliders, for example, use an extremely high aspect ratio wing (long and thin) to increase the area that is unaffected by vortices. Most modern aircraft use some sort of winglet technology to block the flow of air at the tips. These winglets have the ability to reduce drag by five to seven percent but increase an aircraft’s weight and can be very costly to install.

Wingtip Vortices, Lift’s Ugly by-Product

Like fighting fire with fire, the most effective means to battle wingtip vortices is good, old-fashioned air. Unfortunately, this means flying really close to the ground. Realized in the distance between the hard stuff and an aircraft’s given wingspan, or in the case of helicopters, the rotor diameter, ground effect can reduce induced drag up to 50% and increase lift. Nice stuff. Ground effect is more pronounced when flying smaller aircraft that have lower wing loading and often lack spoilers that reduce the influence of ground effect. And a low wing aircraft like the Cirrus can experience increased ground effect forces quicker than compared to a high-wing aircraft like a Cessna 206. For helicopters it’s a function of disc area and rotor RPM. A helicopter can hover at almost twice the altitude in ground effect (IGE) than it can out of ground effect (OGE), thanks to its relatively large disc area.

Spanwise Ground Effect

First “discovered” and researched in the 1920s, ground effect is comprised of two separate aerodynamics creatures – spanwise and chordwise dominated ground effect. As an aircraft’s wing or rotor approaches the ground, wingtip vortices have less room to develop. Their growth is literally stunted by hitting the ground before they can fully develop (much like a few childhood friends of mine). These vortices are also pushed outward from the wing and create a virtual appendage that has a greater spanwise axis (the distance measured from the wing’s root to the tip) than the geometery of the wing. At a height of ten percent of the wingspan, or roughly five feet in a Cirrus, it’s estimated that spanwise dominated ground effect can reduce induced drag by up to 50 percent. The reduction of induced drag allows the wing to develop more lift for the same angle of attack. Ground effect’s strength varies based on aspect ratio wing loading (the weight of the aircraft divided by wing area), speed, weight and a number of other factors.

Chordwise Ground Effect

The second positive benefit of flying close to the ground is the increase in lift received thanks to chordwise ground effect. Chordwise ground effect is responsible for the lovely cushion of air that we find incredibly beneficial as helicopter pilots yet somewhat annoying (but also useful) as airplane drivers. A wing’s chord is the measurement from the leading edge to the trailing edge; it’s the wing’s width. As a wing approaches the ground it creates an area of high pressure air called ram pressure between the wing and the surface. This increase in air pressure on the wing’s underside compliments what the airfoil is already trying to activate on its own, providing a boost in lift. The bigger the chord, the greater the power of chordwise ground effect. As an example, check out Future Flight on Page 18, where we take a much closer look at hovercraft and wing in ground effect (or WIG) vehicles called wingships that rely purely on ground effect to fly. The WIG technology-enabled wingships employ short, fat wings to generate significant ram pressure and a very large lift-to-drag ratio. It’s a combination of these two ground effects, span-wise and chord-wise, that co-mingle and work together to reduce drag by squashing wingtip vortices and increase lift by improving air pressure to allow for a more a influential ground effect. There have been countless accidents when an overloaded aircraft, whether an airplane or helicopter, leaves ground effect behind only to realize there’s not enough power to deal with the loss of lift and increased drag free-air flying requires. An understanding of ground effect’s inner workings can only help make us safer, smarter and perhaps most importantly, gives us one more topic to sound intelligent about at cocktail parties.

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The Heart and Soul of Maine - Acadia National Park

Acadia National Park is the heart and soul of Maine’s coastal heritage. Nestled between the mountains of Acadia National Park and the crystal blue Atlantic Ocean is Bar Harbor, a vibrant and historic community of artists, writers, lobster fisherman and outdoor enthusiasts. Located on Mount Desert Island, the third largest island on the eastern seaboard, Bar Harbor has enchanted visitors throughout the ages with its incredible natural beauty, cultural traditions and endless opportunities for recreation. Surrounded on three sides by the mountains of Acadia National Park, The Hancock County-Bar Harbor Airport serves as the perfect base for exploring the park. Whether you’re flying, walking, hiking, biking, or kayaking, Acadia National Park is just minutes away.Maine is world renowned as a spectacular travel destination, and the Hancock County-Bar Harbor Airport gives you easy access to the heart of Downeast Maine. It's a great place to live, work and play. Whether you come for a day, relocate your company or stay for a lifetime, you can "get here from there." We offer lots of information to help you plan your next trip to our area. The Hancock County-Bar Harbor Airport (BHB) is conveniently located half way between the City of Ellsworth and the Town of Bar Harbor. Modern facilities, state of the art instrument landing systems and a full range of services combine to make Hancock County-Bar Harbor Airport a safe and efficient year round airport with a very high rate of reliability.

Columbia Air Service - Bar Harbor

Columbia Air Services’ facility at Hancock County-Bar Harbor Airport is a popular destination, especially in the summer months when it serves the ever-growing tourist traffic. Their facility includes a 6,400 sq. ft. and a 3,200 sq. ft. storage hangar; a 5,880 sq. ft. maintenance hangar and a 3,844 sq. ft. office and shop area. From the end of June through Columbus Day, all pilots and families can jump on the Island Explorer which provides bus service between the airport and several locations on Mount Desert Island. Island destinations include village centers and Acadia National Park. For further information call Downeast Transportation at (207) 667-5796 or visit their website at www.exploreacadia.com. Welcoming more than two million travelers a year, Acadia covers more than 40,000 acres. The park encompasses nearly half of Mount Desert Island, a scattering of smaller islands, and the Schoodic Peninsula. The only national park in the Northeast, Acadia is big on attractions. Pilots can fly-over, drive, bike, or hike up Cadillac Mountain, the highest point on the East Coast, to watch the sunrise and be the first in the United States to see the dawning of a new day. Later they can stop in for popovers and strawberry jam at the famous Jordan Pond House, a delightful restaurant founded in the early 1870s. One of the most amazing features of Acadia National Park is the interlaced system of hiking trails and carriage roads. With varied lengths and difficulty levels, the 130 miles of trails appeal to everyone from casual walkers to seasoned triathletes. Hike, bike, snowshoe, cross-country ski or go on horseback.No trip to Bar Harbor and Acadia National Park would be complete without sampling some of the world’s finest lobster. And Bar Harbor knows how to do lobster. You’ll find lobster pounds where live lobsters are freshly steamed outdoors in wood-fired lobster pots. You’ll also find all kinds of lobster recipes from lobster crepes for breakfast and fresh toasted lobster rolls for lunch to dinner favorites like steaming bowls of lobster stew, heavenly lobster Newburgh, and complete shore dinners.

Bar Harbor and Acadia National Park have something for everyone. Whether you are looking for an outdoor adventure like hiking, kayaking, or biking or maybe just some of Maine’s best dining and accommodations, there is a unique experience awaiting you, all set on the back drop of the most picturesque scenery you will find anywhere. We look forward to seeing you soon and hope you enjoy your stay.

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A Piaggio Migration

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Behold the Shrike

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The Weary Airshow Patron

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Backcountry Jaunt

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Hold on tight Tyson!

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Not a Bad Day at the Beach

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Planes, Places, and People - Chicken Soup for the Pilot’s Soul

There’s a lot of buzz surrounding us these days with the political flavor of the day; the debate over national health care reform. “We the People” has taken on a resurgence of activism to remind many of us what a great country we live in, And, one we intend to keep. Although the players of these games surround us with a gloomy air of despair or protest.Have you noticed where the oasis of happiness and hope resides? It’s at air shows! Honestly, do you see anyone without a big grin and wide eyes (behind the sunglasses) watching an airshow filled with thrilling aerobatic shows, warbirds or vintage planes from the Golden Era of yesteryear? How about those new designs of light sport aircraft and experimental kits to make flying more affordable --- that’s gotta give some people hope to keep flying in their budget! The scoop I’m hearing from those that keep track of airshow attendance is that events like the Sun n Fun 2009 (138,240) and AirVenture 2009 (578,000) are drawing amazing crowds, even in this crummy economy! People are flying in from all over the world to witness history in the making like the arrival of Virgin Galactic’s White Knight Two and the Airbus 380 (which provided a nice lesson in crosswind landings at KOSH – Ouch! I would anticipate a future NOTAM reflecting a lower TDZE on runway 36).

Last year, I showed up with my rented motor coach to stay in Camp Scholler starting on Monday the week of AirVenture 2008 and there was lots of room to pick a spot for the week long RV experience. This year, I showed up a day earlier and was fortunate to find a spot at all! This was a testament to the eager anticipation for all of us enthusiasts that desperately need an injection of excitement as we battle the forces of anti-liberty and anti-freedom trying to chew away at our chosen hobby and professions in aerospace. In the circles of aviation, this kind of attendance is a clear demonstration of what “We the People” hold near and dear to our hearts. Don’t ever lose that sense of fellowship shared inside the crowds with the pilots, mechanics, engineers, entrepreneurs, and others that keep the vision alive in our hearts for future generations.

Step Back for a Moment

But, stepping back for a moment from the industry and events created, what is the real benefit or mission of these shows or organizations that sponsor them? What’s in it for us? What’s in it for the future and legacy that we are building? Allow me to opine at the possibilities. The AOPA Foundation, Inc., a tax-exempt charitable, educational, and scientific organization, educates the public on the value of general aviation. The AOPA Foundation works to improve aviation safety, preserve and improve community airports, and encourages learning to fly for career and personal benefit – all in the interest of ensuring the future of general aviation in America. The Experimental Aircraft Association promotes the fun and camaraderie of sharing the passion for participating in the flying, building, and restoring of recreational aircraft with a very passionate community of aviation enthusiasts. It now includes antiques, classics, warbirds, aerobatic aircraft, ultralights, helicopters, and factory manufactured aircraft. In parallel, the EAA Young Eagles program gives young people the opportunity to take a flight with a qualified pilot as an individual “up close” introduction to the world of aviation. The Reno Air Racing Association (RARA) mission is to perpetuate the most unique air racing event and aviation experience in the world by combining the fastest motor sport with spectacular military and civilian air entertainment. In addition, the Reno Air Racing Foundation was established to educate the public, especially young people, about the world of aviation, emphasizing the role that air racing has had on the evolution of the aviation industry.

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