Category Archives: Flying

FLIGHT OF THE MONTH: Veteran’s Day at The Pik-N-Pig

November’s flight-of-the-month found Connie and me flying to Gilliam-McConnell Airfield in Carthage, North Carolina on the 11th. We picked this airport for the pork barbecue restaurant located right on the field, the Pik-N-Pig, but found much more on our little Veteran’s Day adventure.

The Pik-N-Pig sits close to the runway at Gilliam-McConnell Airport

The Pik-N-Pig sits close to the runway at Gilliam-McConnell Airport

A mere 22 nautical miles from Raleigh Executive Jetport (KTTA) near Sanford, the flight to Gilliam-McConnell lasted about 20 minutes. But the destination runway was short, so after we took off from Raleigh Exec in our Wings of Carolina Flying Club four-seat Cessna 172, I asked Connie if she’d mind if we did a touch and go before heading to the southwest. With relatively low windspeeds, I didn’t anticipate any trouble landing at Gilliam-McConnell, but its asphalt strip runs about half of Raleigh Exec’s 5,000 feet, and I wanted to see how short I could land in the current conditions.

Given the day’s winds and the orientation of the two runways, a landing at Raleigh Exec would give me crosswinds similar in magnitude though opposite in direction to landing at Gilliam-McConnell – a good test. After a smooth take-off and once around the pattern, we could have stopped our landing roll-out well short of the runway’s halfway mark – a confidence-builder. Time to go get some pig.

Tall trees surround Gilliam-McConnell’s narrow airstrip. With its orientation nearly perpendicular to our approach from the east-northeast, we didn’t see the field much before we were on top of it. Connie noted after we landed that she never saw the field until we had lined up on our final approach. Guess she had confidence that I was making three 90-degree turns for a good reason. We overflew the field intending to turn left onto a downwind leg for our landing on runway 31. An oncoming Piper had announced it was inbound from the west, and just before starting my turn onto the downwind, I spotted it out my left window.

“Gilliam-McConnell traffic, Cessna 53587 has inbound traffic from the west in sight. We’ll do a 360 here and then enter a left downwind for runway 31, Gilliam-McConnell.”

Better to make a turn than risk a mid-air collision. Coming out of the turn, it took a few seconds to pick out the other plane as it initiated its turn to base. We were number two for landing. Another inbound aircraft mentioned it was five miles south, so we kept our eyes peeled for that one as we made our turn to base above the tall trees rising closer below us.

Did I mention the tall trees surrounding the runway? The winds remained calm on final approach, well, until we reached the tops of those tall trees. They form a little, that is, narrow, tunnel down to the end of runway 31. We flew from smoothly calm wind into a bit of buffeting as we dipped towards the tops of those trees.

Have you ever been in a commercial jet climbing up or descending through a cloud layer? As you approach the elevation of the clouds, you get an exciting sensation of your speed as the clouds go zipping by. Jets go really fast, but you don’t often realize how fast until you see those clouds zooming along right outside your window.

Those trees surrounding Gilliam-McConnell, they didn’t zip by that fast since our approach landing speed was only about 65 miles per hour, but they were close. It felt like entering a tunnel as those tree tops rose up above us as fast as the ground reached up for the belly of our aircraft. The buffeting kept me from fully appreciating the tunnel effect as I kept us on the runway’s centerline at an appropriate descending slope and airspeed.

We passed over the numbers at the end of the runway, in this case a big 31, and touched down near the center of the black asphalt strip several hundred feet later. With room to spare, we turned left onto the taxiway just past the runway’s midpoint, and headed back to the grass outside the Pik-N-Pig.

The pork barbeque melted in my mouth, worth the $105 per hour it took to fly there. During the meal we enjoyed watching planes land and take off 40 yards from our table. Then we went outside to browse the monuments and parked P-40 World War II era fighter between the restaurant and the runway, and discovered another reason to visit Gilliam-McConnell airport.

First, on one monument we discovered that the second of the two people the airfield was named after had been a member of the Lafayette Escadrille, an elite First World War fighter squadron based in France. James McConnell joined up in 1916, eager to fight against Germany. He died in the skies above the Somme battlefield on March 19th, 1917, flying his biplane in a dogfight with two German aircraft. He was the last American aviator to die in France before the United States officially entered the war alongside France.

Two additional monuments commemorated another fallen American aviator and North Carolina native, this one Robert Hoyle. Second lieutenant Hoyle flew P-40 Warhawks as a member of the 74th Fighter Squadron, better known as the Flying Tigers. These volunteer American aviators fought for China against the Japanese during World War II. Robert Hoyle was shot down on October 6, 1944 over mountains in Hunan Province. He was returning from a strafing mission, ran into bad weather, and crashed.

P-40 Warhawk in China with its Flying Tiger nose art

P-40 Warhawk in China with its Flying Tiger nose art

Residents of Guidong County, near the crash site in south central China, found the wreck and his body shortly after the crash, but the debris left little in the way of identification. They only knew he had been fighting for them, and they buried him nearby with full honors under a monument with the simple epitaph, “American Pilot of the Flying Tigers.” For over 60 years, citizens in Guidong County cared for the hero’s grave and wondered who he was.

P-40 Flying Tigers wait at an airfield in China during WWII

P-40 Flying Tigers wait at an airfield in China during WWII

Robert Hoyle’s family knew only that he’d been reported missing in action. In 1945 the U.S. Army Air Force officially presumed he was dead. In 2005, a team of American military forensic experts visited three provinces in China, and during a month-long trip examined the remains buried in Guidong County. Based on DNA evidence provided by family relatives, they identified those remains as belonging to 2nd lieutenant Robert Hoyle.

Sixty-one years after he died fighting in a foreign country, Robert Hoyle’s family discovered his fate, and the Chinese citizens learned the name of the hero they’d been honoring for over half a century. In April of 2006, Chinese officials accompanied Robert Hoyle’s remains on a long-overdue return flight to American soil. After a burial service, 2nd Lt. Hoyle went to his final rest in High Falls, North Carolina.

P-40 Flying Tiger model outside the Pik-N-Pig at Gilliam-McConnell Airport in Carthage, NC

P-40 Flying Tiger model, “Junkyard Dog,” outside the Pik-N-Pig at Gilliam-McConnell Airport in Carthage, NC

After crawling over the P-40 replica at Gilliam-McConnell, it was time for us to return home. Climbing out at 80 knots we quickly cleared those tall trees surrounding the airfield and turned to a 50-degree heading that would take us to Raleigh Executive Jetport. Reluctant to end our Veteran’s Day adventure, I asked Connie if she’d mind if we did a touch and go. She did not mind. Minutes later we shut down on the ramp outside the Wings of Carolina hangar, recorded 1.0 hours from 53587’s Hobbs meter, and tied her down.

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HURRICANE GENESIS: A science review by Mark Betancourt in Air & Space Smithsonian

I’ve enjoyed Air & Space magazine for years, but an in-depth article by Mark Betancourt in the August 2015 issue goes above and beyond. I expect informative technology reviews and personal interest articles sating my inborn curiosity in aviation and space developments, but this story is one of the best science reviews I’ve read in a popular magazine.

Mr. Betancourt elucidates the state and the art of hurricane science, describing the methods and tools used to ask and answer the important questions. Of course, that’s how scientists operate, figuring out how to devise and conduct the tests required to solve the unknowns. Here we have the story of hurricane genesis focused on those tools and techniques climate scientists have used in the past as well as the new methods used today. But this story goes even further, into the future, laying out the questions we need to answer about how hurricanes begin.

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Eye wall of Hurricane Katrina from NOAA aircraft

Betancourt does all this without forgetting how Air & Space magazine adroitly grabs reader’s attention with personal stories about real people. So we read about the first pilot to penetrate a hurricane in an airplane. Joseph Duckworth, an Army Air Corps flight instructor and unusually skilled instrument pilot, was eager to show his British student pilots the capabilities of the AT-6 Texan aircraft they liked to ridicule. In July, 1943, he flew an AT-6 into a hurricane off Texas’ Gulf Coast, and returned unscathed. A fascinated colleague asked Duckworth to take him into the hurricane on a repeat of his daring flight. He did so, again returning safely.
AT-6 Texans
Restored AT-6 Texans flying at Oshkosh, July, 2015

Thus began the era of aircraft flying into a hurricane to take measurements of its strength and movement. P-3 Orions and C-130s have done it now for years, but here we taste the future with details of large and small drones used to study hurricanes up close.

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NOAA WP-3D Orion Hurricane Hunter

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Global Hawk outfitted for hurricane duty with NOAA

The large drone is the Global Hawk, 44’ long with a wingspan of 130’, weighing as much as 32,000 pounds and able to stay aloft in and above a hurricane for 18 hours. The Global Hawk is big enough to release dropsondes that fall through the storm sending back measurements.

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Coyote drone dropped into hurricanes by NOAA

At the other end is the Coyote, a three-foot long handheld drone with a six-foot wingspan weighing just seven pounds and capable of short two-hour flights through a hurricane. The Coyote is itself deployed from a manned P-3 Orion Hurricane Hunter.

The Genesis Part

Along with the personal interest stories and latest technology updates, Mr. Betancourt delivers sound science surrounding the still mysterious forces that coalesce to create a hurricane. He starts with three things we understand, evaporation, convection, and condensation. Water evaporates from the warm ocean surface making the air at the ocean’s surface less dense, causing it to rise – convection. As it rises, the air cools and the evaporated water molecules begin to condense into small droplets. When the droplets grow larger gravity forces them to fall back into warmer air below. When this happens, the droplets partially evaporate, cooling the air around them. This newly cooled air continues to fall, being heavier than the warmer air below. This is a classic downburst of rain and cool air, and it replaces the warm surface air mass that fed convection in the first place. Further evaporation and convection is stopped, and the storm is over.

I knew about evaporation, convection, condensation, even downbursts. But I didn’t know downbursts kill the storm.

What does this have to do with the mystery surrounding the genesis of a hurricane? As a cluster of convective storms come together, the middle layer of air through which rain falls becomes too warm and humid for the raindrops to evaporate, so there is no cooling. The downburst stops, or never really gets going, and rather then being cut off, the storms continue to grow bigger. More evaporation leads to more convection across a broad swath of the ocean surface as the storms coalesce and strengthen. A low pressure center builds as the warm air rises en masse. Cool, dry, and dense air from outside the low pressure center rushes inward from all directions, pushing the warm moist air up faster, allowing more evaporation to occur at the warm ocean’s surface, pushing more convection and ever lower pressure. The inward rushing air speeds up, further increasing surface evaporation and convection, and a positive feedback loop leads to a stronger and stronger storm. Bingo, a hurricane is born.

Unanswered questions include what causes a cluster of storms to coalesce rather than stay isolated and dissipate as they normally do, and what is the role of warm ocean surface waters? But thanks to this well-designed story that focuses on the tools, techniques, and unknowns surrounding the birth of hurricanes, those questions come forth with clarity. That’s how science operates. What’s rare is to see this in-the-field process of scientific investigation form the basic structure of a compelling story.

AIRPLANE OF THE MONTH – or – “What do you mean you won’t fill my order?!”

Watching the Smithsonian Channel’s, Planes that changed the world: The DC-3 last week, increased my affection for a beautiful old plane. As with classics like the Spitfire and the P-51 Mustang, there is something pleasing about the lines of the DC-3. And perhaps just as the simplest explanation often makes more sense in scientific explanations, so might visual appeal signal greater engineering efficiency and strength.

The story of the DC-3 starts with a bizarre twist shortly after The Boeing Company created its B-247 passenger plane. First flown in July of 1933, the B-247 is considered the first modern airliner with all metal construction, high cruising speed, ability to land at low speeds, and capable of flying on only one of its two engines. Boeing promised United Airlines, which it owned, the first 60 aircraft off its assembly line, and thus begins the rest of the story.

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Photo credit: Malcom Nason
Boeing 247, the one that started the ball rolling when Boeing put off TWA’s potential order in favor of United Airlines!

TWA also wanted the B-247 for its operations, but Boeing told TWA it would have to wait. Unwilling to sit on the sidelines and risk losing the commercial airline business to United, TWA queried Boeing’s competitors to see if any of them could develop a similar aircraft. Donald Douglas was one of those competitors.

Douglas and his team of engineers accepted the challenge, and began work on the DC-1, or Douglas Commercial-1. But these were no ordinary engineers. Among others the group included Jack Northrop and Dutch Kindelberger. Northrop designed the Lockheed Vega, the high speed six-passenger monoplane built in 1927 that Amelia Earhart flew across the Atlantic and Wiley Post flew around the world. Kindelberger would go on to design the P-51 Mustang of WWII fame. Douglas’ crew doubled down and came up with an aircraft that left the B-247 in the dust. Here’s how.

As originally designed, Douglas’ new plane evidenced instability due to a center of gravity being too far forward. His engineers quickly used wind tunnel tests to discover that a swept-back wing would move the aircraft’s center of gravity towards the tail. This innovation not only fixed the balance problem, but also increased the aircraft’s speed.

below: DC-1 showing swept back leading edge of wings (arrow pointing to blue line)
pushing center of gravity rearward
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above: DC-1 with turbulence-reducing fillet (gold ellipse) connecting wings to the fuselage

Next, the Douglas crew worked to further increase the aircraft’s speed and stability by fine tuning it’s aerodynamic design. They came up with the novel idea of adding a fillet, or curved connection between the wings and the fuselage (see the fillet circled in the photograph above). This single design change added 17 mph to the DC-1’s cruising speed.

But Douglas’s engineering marvels were not finished. They added landing flaps. They didn’t invent them, but they recognized the importance of having flaps that would reduce the aircraft’s landing speed, enabling it to operate out of the shorter airfields common in the 1930s.

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DC-3 with flaps extended

Douglas now had an aircraft that met or exceeded TWA’s requirements for cruising speed, useful load, takeoff and landing distance and speed, and ability to take off and land on one engine. They delivered the first model to TWA just four months after Boeing delivered its first B-247 to United.

below: boxy fuselage of the DC-1, provided less space & a weaker structure
DC-2_headon

But there was one more surprise coming from this enterprising crew, and it also came out of a request, this time from American Airlines. American wanted an airliner that would allow passengers to slumber in sleeper compartments on long-distance flights. A skeptical Douglas took it to his engineers. They decided to build a circular fuselage rather than the box-like shape of current airliners. This was not the first airplane with a round fuselage, but it was the first built for commercial air travel, and it added roominess, strength, and speed to Douglas’ design, now designated the DC-3.

DC-3’s circular fuselage increased interior space & structural integrity
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DC-3 on the ramp at Raleigh Executive Jetport (TTA) in Sanford, NC

The DC-3 entered service in June of 1936. It was one of the fastest aircraft of its time. It’s predecessor, the DC-2, had come in second to a specially-modified Havilland Comet in a London to Melbourne, Australia air race in 1934. The DC-3, which still flies commercially today, cruises at 207 mph, can reach a top speed of 230 mph, has a useful load of over 8,000 lbs., and a service ceiling of 23,200 feet.

One other measure of its prowess might be the number of names by which it is known. Here in the U.S., veterans and enthusiasts might call it the Goony Bird, the C-47, or the Skytrain. The latter two refer to the military transport version that served in every theater of World War II. In England they called it the Dakota, and in Russia, the Lisunou Li-2. Whatever you call it, it’s a beautiful airplane.

AIRSPACE CROWDING

As a general aviation pilot, a story about increasing conflicts among fliers sharing the skies overhead carries an intrinsic interest with a safety overtone. As a biologist and a birder, realizing the story is about wildlife-human aerial interactions awakens quite a different interest, still with a safety overtone.

Sergio Lambertucci, a wildlife ecologist at the National University of Comahue in Argentina, along with Emily Shepard, and Rory Wilson, wildlife scientists at Swansea University in the UK, outline the evidence in a thorough review of where and when human and wildlife uses of airspace can lead to problems (see Science magazine, 1 May 2015, 348(6234), pp. 502-504).

Lambertucci et al. include on the human side what you would expect, fixed-wing airplanes, helicopters, and of course, unmanned aerial vehicles (UAVs) or drones. But you may be surprised that human use of the near-surface airspace extends beyond aircraft. Buildings, wind turbines, power lines, and antennae also project well into the lowest hundred meters of airspace within which most flying animals operate.

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Piper Cherokee wing over West Virginia headed to Oshkosh

These three inclusive thinkers also remind their readers that less visible life forms exploit earth’s airspace; bacteria, algae, and fungi. I must admit, even wearing my biologist hat I never considered the impact of our use of airspace on microbial life. But aerial microorganisms can serve as condensation nuclei promoting cloud formation. Changes in the abundance and distribution of these organisms as a result of air pollution and wind flow patterns altered by tall buildings can impact precipitation and weather.
 
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Bald eagle over Jordan Lake dam, North Carolina

Key to mitigating adverse impacts of human activities is a better understanding of just how and where and when wildlife use airspace. Beyond the obvious bird migration patterns that can extend across continental and oceanic boundaries, think about the more mundane, daily use of airspace by our avian friends to find food, mates, and nesting space. These smaller scale dynamics require understanding animal movements in the horizontal and vertical dimensions at scales from meters to kilometers, and how these uses change during the course of a 24-hour day.

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Great blue heron over the Apex Reservoir, North Carolina
 
Armed with better knowledge of wildlife habits of airspace utilization we can design and place buildings and other structures to minimize conflicts. Windows can include markers to alert flying animals, the newest technologies employing ultraviolet lights highly visible to birds. Radar can detect approaching flocks of birds and enable structural modifications to limit impacts, such as reducing wind turbine speeds. In selected instances, full-time or time-sensitive airspace reserves might provide the best alternatives.
 
With over 500 hours in the left seat of single engine aircraft, I’ve only come close to a vulture or other bird a handful of times, almost always in the landing or take-off pattern. But as Lambertucci et al. report, there have been over two hundred people killed by birds striking aircraft, and the cost of bird strikes in the U.S. alone exceeds $900 million per year. One year, 2013, saw 11,315 bird strikes. Better understanding of wildlife use of airspace at small and large scales should enable us to reduce these and the variety of more subtle human-wildlife conflicts in our skies.

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A student’s father took me up in his Christen Eagle!

 

The Evolution of Aerial Combat

Luna moth resting on a screen at the Len Foote Hike Inn in north GeorgiaIMG_3015

This was one of a few luna moths we saw while we were hiking this May in Amicalola Falls State Park in the north Georgia mountains. With apparently little to do in the daylight hours, these huge specimens mostly just hung around our lovely accommodations at the Len Foote Hike Inn. When nighttime comes, things might get a bit busier.

Luna moths, as large and impressive looking as they are, have little chance against the weight and teeth of a hungry bat. But as long ago as 1903 a published report suggested that the extended hindwing tails dragging behind the wings of saturniid moths, the family of moths that include luna moths, might serve to divert bat attacks away from crucial parts of the moth’s body. The hindwing tail may present an acoustic return of the bat’s sonar that proves more attractive than the main wings and body of these moths. Evidence of this was discovered by Jesse Barber and colleagues at Boise State University and the Florida Museum of Natural History.

The expendable hindwing tail does little to improve basic flight.IMG_3014

They presented luna moths with and without their hindwing tails to big brown bats in controlled settings and found that bats captured only 34% of moths with intact tails, but captured 81% of bats with their hindwing tails removed. Tail removal did not otherwise injure or significantly alter the flight characteristics of the moths.

The link below is infrared video of a big brown bat’s unsuccessful attack of a luna moth. The bat appears to aim for the hindwing tail, and even though the moth seems to lose part of its tail in the attack, it escapes.

BAT ATTACK VIDEO

Between 1937 and 1942, human technology, perhaps unknowingly, perhaps not, suggested imitating nature. British researchers thought that dropping strips of aluminum foil from aircraft might deflect German radar and allow British bombers to remain undetected as they approached targets over Germany during World War II. They called this dropped chaff, Window, and it appeared to work. German fighters could not be vectored to meet the approaching bombers, and ground-based anti-aircraft fire had to rely on visual sightings rather than advance alerts from radar.

Today, military aircraft flying in harm’s way fire flares behind them to distract enemy anti-aircraft missiles. The heat of the burning flare will attract the heat-seeking missile away from the vulnerable and slow-moving aircraft.

Seahawk helicopter firing anti-missile flares.chaff_Seahawk

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Jesse R. Barber, et al. 2015. Moth tails divert bat attack: Evolution of acoustic deflection. Proceedings of the National Academy of Sciences, Vol. 112 no. 9, p. 2812–2816, doi: 10.1073/pnas.1421926112 Continue reading

February’s Bird-of-the-Month

Sunset’s shadow fell about two-thirds of the way up the wall of tall pine trees lining the eastern shore of the lake. I thought it would be neat to get the rising shadow on video, but realized it would progress too slowly to enjoy in real time, perhaps a time-lapse would work. A blustery northwest wind pushed a few swells larger than I usually see on this three-quarter mile long, tree-shrouded lake. A rusty red-brown bird blew in on one gust, soaring down over the lake. Hawk. It pivoted in the winds, dark in the shadows below the sunset. Its swerve sent it streaking back up into the dying sun, shining pale yellow underwings bright against the darkened sky. Another gust and turn and it dived back into the shadows below, swiveling in a tight circle near the shoreline, searching for dinner? Then back up on the next bluster, seeming to enjoy playing the momentary meteor. Better than a time-lapse video of a slowly settling sun, this hawk swiftly banked around for one last flash of yellow before a few shallow beats of brown-red wings sent it up and over the treeline with the sunset. sunset021215 Sunset over the Apex Reservoir 5:45 PM on February 12, 2015

AVIATION: The Invisible Highway – a review of the trailer!

There’s a new documentary coming out next year called, Aviation: The Invisible Highway. The trailer claims that…“When airplanes were invented, their purpose was simple, to take us faster and farther.”

I disagree. Airplanes were invented because people wanted to go up into the air. They wanted to fly above the ground. They wanted to see their world from a new perspective, from above. Speed began as a necessary ingredient for flight, and distance became an instant and unavoidable by-product of that speed. But more important than speed and distance was the new perspective and what it brought to those who took to the air.

Speed and distance matter. But at first they were side-effects of the magic of flying. Take someone flying for the first time in a small plane and what they focus on is the view of the ground, the Earth below, and if the sky carries some puffy clouds, they will marvel at the enormity of the third dimension they barely appreciated from the ground.

I fly for that third dimension, a perspective that opens your eyes and your mind. A little vignette I found once on a small poster of a single engine aircraft captured it: “Flying, you take off, but you never come back down.”

DSCN0301(1)Picture taken from a Wings of Carolina Flying Club Piper Warrior on the way to the Oshkosh Airshow in 2005.