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A pilot was hurt in what appears to have been a forced landing on the rooftop of a building in Pomona, California, on Sunday. Circumstances of the incident weren't clear at our deadline but news copter images show the aircraft to be intact with a collapsed nose gear. It appears to be a Piper Cherokee 140. Authorities are not describing the incident as a crash and have confirmed that it is the pilot who was hurt. The aircraft passenger was not taken to the hospital.

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Early-year new aircraft shipments are down in 2016, according to the General Aviation Manufacturers Association's latest report. For the first quarter of this year, total GA airplane shipments fell 3.7 percent compared to 2015, GAMA reported Friday (PDF). Piston aircraft remained relatively steady with 191 shipments for the first quarter of 2016, with 193 for the same period in 2015. Meanwhile, turboprops saw a 6.8 percent drop in the first quarter with 109 shipments, and business jet shipments fell 4.7 percent to 122 aircraft. While the decline in the airplane category isn't as severe as the double-digit fall seen in early 2015, falling numbers in rotorcraft shipments persisted with an 18.9 percent decline, similar to numbers reported a year ago. Turbine rotorcraft took the biggest hit with a 27 percent drop in shipments, while the piston category remained unchanged with 60 units shipped. 

GAMA said a soft global market is among the factors affecting shipments, while in the U.S., the industry awaits a boost from regulatory reforms including the FAA's pending reauthorization bill. "Despite these headwinds, our industry continues to invest in research, development, and certification of more efficient and safe products. Therefore, actions taken by elected officials to stimulate R&D and improve regulatory efficiency have a far-reaching impact on the economy," said Pete Bunce, GAMA president and CEO. "Next week, GAMA board members will be on Capitol Hill, pressing home the need for these changes with members of the U.S. Congress. We will be calling on them to move forward on bipartisan FAA reauthorization and appropriations legislation that expedites delivery of new products to market, better leverages industry and regulatory resources, and reduces costs to customers."


Airplanes that fly themselves already exist and the accepted wisdom is that we're not too far from the day when all airplanes will be robotically operated. But maybe not. At the first annual Sustainable Aviation Foundation symposium in Redwood City, California, three experts in the field were asked about the immediate prospects for commercial autonomous aircraft and they offered three different opinions.

Joshua Portlock, founder of a survey drone company called ScientificAerospace, told attendees at SAF that the hardware and technology exist for reliable autonomy and that the only thing preventing it is the regulatory apparatus. "I have a different view," said Willam Parks, chief engineer of Aerovironment, an engineering and design company with alternative aircraft experience extending back more than two decades. "The more I work with autonomous aircraft, the more impressed I am with pilots," Parks said. He said the problem with autonomous systems is that even at their current high state of development, they simply aren't good at detecting and correcting anomalies without human intervention. And there always are anomalies. "When systems aren't working right, it's very hard to figure out why," said panel member Kevin Jones, a professor at the Naval Postgraduate School in nearby Monterey, California.

All three panel members reported different experiences and attitudes with regard to robotic airplanes. "People in general, who are not pilots, worry about collisions," Jones said, "But I talk to my friends who are pilots and they're not worried at all," he added. Park compared acceptance of autonomous flight with acceptance of elevators without operators. "I nothing goes wrong, people will get used to it," Parks added, but it will be gradual.


Hydrogen fuel cells have long been discussed as a potential power source for vehicles, including aircraft, and researchers at the German aerospace center, the DLR, believe that technical barriers can be overcome in the near term to make hydrogen a practical fuel source. Speaking at the first annual Sustainable Aviation Foundation symposium in Redwood City, California, this week, the DLR's Josef Kallo told attendees that research on practical hydrogen cells is much further along than many people realize. In this exclusive AVweb podcast, Kallo explained some of the DLR's research projects. Listen to a podcast interview here.

"Our first goal now is to show that the functionality of the fuel cell can be used for aircraft propulsion and our next project, HY4, will show that it's possible to have four people on board and travel with hydrogen in an airplane," Kallo said. As for obtaining hydrogen, Kallo says DLR's work suggests it can be economically reformed from abundant natural gas or from electrolysis of water. 

Kallo said hydrogen cells in use now are capable of about 50 to 52 percent efficiency and that this will improve with coming generations of cells. Energy density of research cells is about 450 wh/kg, more than twice what the best lithium-ion batteries are capable of. One of the interesting projects Kallo described was a fuel-cell powered nosewheel taxi motor for an Airbus A320, which was demonstrated in 2012. The goal was to save fuel by taxiing under hydrogen power to the runway before starting less-efficient turbofan engines. Kallo said the DLR believes hydrogen fuel is practical for small aircraft now and could be for airplanes up to 19 seats within 10 years.


Hydrogen fuel cells are improving in efficiency and are technically viable for small aircraft but until gasoline gets a lot more expensive they won't be able to compete. AVweb's Paul Bertorelli spoke with Dr. Josef Kallo on the promise and challenge of the technology.

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A Russian-built An-2 biplane made an off-airport landing near San Bernardino International Airport near Los Angeles Friday. The 1940s aircraft, owned by the Commemorative Air Force, was on final approach for the airport when the engine quit. "I thought we had the airport made. But when we got closer, it was obvious we weren't going to make it," pilot Cliff Heathcoat told the Press Enterprise. Heathcoat and a passenger were unhurt when the aircraft flipped and landed on its back after hitting power lines. The airplane is intact but obviously damaged.

When things got quiet, he headed for the only patch of open ground in the area. "Dude, there were houses everywhere," he said. "We put it down in a little patch – maybe 10 to 20 acres – with houses all around. That was scary. We were fortunate." The bright yellow aircraft, which is about the size of a DC-3, is powered by a single radial engine. It's known as Big Panda and is a familiar sight at airshows in southern California.


Canadian authorities are investigating an incident that could potentially affect the airworthiness of thousands of Piper Cherokees. Manitoba flight instructor Tom Larkin was on short final with a student when the control column broke off in his hands. "Somewhere below 50 feet as I eased back on the control column to assist the student with his landing, we heard a loud 'snap' and the control column went limp," said Larkin. "As I always have the student trim for hands-free flight there was no change in aircraft pitch and the aircraft continued to land normally," Larkin said. "There was no control of the aircraft's lateral or longitudinal axis. The control columns moved independently for both roll and pitch with no movement of the control surfaces." A mechanic looked at it immediately and found the t-bar control assembly had broken.

Larkin contacted Transport Canada and the broken part was sent to the Transportation Safety Board and both have issued preliminary reports but it's not clear what, if any, further action will be taken. Meanwhile Larkin and some local maintenance engineers removed the control column from an unflyable Cherokee of similar vintage and found a crack in the same place using magnetic particle imaging. Larkin said that indicates to him there might be a problem with all older Cherokees and he's concerned about what he perceives as foot-dragging by the authorities.

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An unmanned airplane made a successful first test of cloud-seeding operations in Nevada, adding a new kind of industrial-use experiment to one of the nation's FAA-designated UAS test sites. The UAS, which weighs less than 55 pounds and has a wingspan under 12 feet, flew for about 18 minutes last week and reached 400 feet, according to an announcement this week from the state's Desert Research Institute. During the flight at Hawthorne Industrial Airport, the Savant UAS released two silver-iodide flares, which are typically deployed by manned aircraft in cloud-seeding operations over Nevada and other areas to increase precipitation.  

Nevada-based Drone America performed the test as part of the state's UAS research. "We have reached another major milestone in our effort to reduce both the risks and the costs in the cloud seeding industry and help mitigate natural disasters caused by drought, hail and extreme fog," said Mike Richards, president and CEO of Drone America. The small, lightweight Savant "is the perfect vehicle to conduct this type of operation due to its superior flight profile, long flight times and its resistance to wind and adverse weather conditions." Nevada's burgeoning drone research industry has gained the state other firsts, including an FAA-sanctioned urban drone delivery test by Flirtey in March that took place in Hawthorne.

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It has again become fashionable in some aviation circles to assert that if only we could return to ways and days of yore by getting rid of some or all of the Federal Aviation Regulations and those who enforce them, all would be well and general aviation would zoom into sunlit uplands and robust financial health. Well, maybe. It sounds good if you say it fast and make some assumptions about human behavior when the police aren't around. In the world of Part 135 flying, it simply isn't true. The cowboy days of operators cutting every corner possible to make a buck while the FAA looked the other way killed way too many people.

We sure aren't perfect today, but it seems to me that a pilot who has had real recurrent training and is about to launch into foul weather in an airplane that has had its squawks fixed stands a lot better chance of arriving at the desired destination alive and well than if the training had been lousy or nonexistent and maintenance just some entries in a logbook. I think it is appropriate to open a page of aviation history, look at it objectively and recognize that there were definitely some "bad old days" in professional aviation.

I happened to come into the Part 135 freight hauling scene at a time when the FAA chose, for whatever reason, to not enforce its regulations on the charter operations at one of the busiest freight airports in the country.

I was like many other professional pilots at that airport, young, burning with desire to fly and didn't much care about how well the airplanes we were to fly were maintained because we not only figured we could fly anything, anywhere, anytime. We also knew that if we didn't go because of weather or condition of the airplane, we would be fired and someone else would go in our place. I only differed from the group in that I was luckier than some. I survived. Not all of my contemporaries did.

Willow Run

By the mid-1970s, Willow Run Airport, created by Edsel Ford on one of his father's farms west of Detroit to build B-24s for World War II, had become the center of the universe for airplanes hauling components needed for the manufacture of cars. The Big 3 auto companies were so huge that there was always an assembly line somewhere that was in danger of shutting down because of a shortage of some part. It meant that any pilot who could scrape up a down payment on a clapped-out Beech 18 with a cargo door and could obtain a Part 135 Air Carrier Certificate could promise traffic managers at the car makers lower air freight prices than anyone else in hopes of getting the call to haul auto parts on short notice. It was unbridled capitalism with constant price wars, minimal training for the pilots, little maintenance for the airplanes and an FAA that was looking the other way.

During law school I had hauled freight out of Willow Run in piston twins. About the time I graduated and began studying for the Bar exam, a number of the operators which had been flying Beech 18s discovered that the per-mile operating cost of a well-used Lear 23 or early 24 was about the same as the Beech, and the Lear got the freight delivered much, much faster.

Suddenly there were Learjets at Willow Run, almost all of which were being operated by folks who had previously done nothing but run single-pilot airplanes.

They weren't exactly sure what to do about the requirement of a copilot in a Learjet. The regs said that the copilot had to go through some training and make three takeoffs and landings in the airplane. However, there simply wasn't the money for any training, or to pay more than a pittance for a right seat warmer and, by gawd, the Learjet 23 panel was set up for single-pilot operation anyhow, even if Lear couldn't convince the FAA to grant single-pilot certification.

The reactions among Lear operators varied. One was reputed to simply tell the lineboys that fueled him that he needed a copilot for a trip and one of the lineboys would go. As he never let his copilots do any flying it worked out fine until the night the lineboys put a guy who'd never even been in an airplane before into the right seat, promising him an airplane ride. Eventually the Lear operators hired and trained copilots, paid them a living wage and put them on the path to upgrade to captain. But in the interim, where I came in, the practice was for an operator to find some pilots he trusted and pay them a small amount to fly right seat in the Lear as needed. Training was on the job—no classroom, no books, no three takeoffs and landings before the first revenue trip and certainly no checkride.

The Introduction

After getting a call from one of the operators who needed another part time copilot, I found myself sitting sideways in the "barrel chair" right behind the copilot's seat of a Model 24B Learjet as we taxied out for 27R at Willow Run. Behind me the rest of the seats had been stripped out and the cabin wrapped with heavy gauge plastic to protect it from the sharp edges of freight.

In short order I learned that all ground ops were on one engine because the fuel burn of the GE CJ610 engines was higher on the ground than in cruise flight (as all Lear pilots, I rapidly became obsessed with fuel). The second engine was not started until we were cleared for takeoff. Moments later I learned that the acceleration of a Lear on takeoff was as nothing I'd ever experienced and that it might well be investigated for its deeply addictive properties. Grabbing the partition behind the copilot's head in a death grip, certain that I would otherwise be hurled aft and pulverized against the rear pressure bulkhead by the stunning acceleration, I knew I was going to like Learjets.

On the second leg of the trip I was assigned to the right seat where I was to talk on the radio, call airspeeds during the takeoff roll and final approach and, upon the captain's command after we broke ground, raise the landing gear and flaps, turn on the yaw damper, turn off the landing lights and generally make myself useful while learning by doing and trying to avoid causing catastrophe. This time takeoff acceleration was a physical entity that shoved me back in my seat, accompanied by view similar to that from a go-kart.

Seated eyes low to the ground, the sensation of speed was vastly amplified as the Lear went scorching down the runway at something approaching a million miles per hour (conservative estimate). I, overwhelmed, did my best to gasp out "airspeed alive and cross check," then "V1" and finally, sharply, "rotate!" With that we pitched up at an improbable angle and tore our way into the sky as sensory overload caused me to struggle to do my simple post-launch tasks. The VSI pegged at 6,000 fpm, a rate I had never seen and my brain, doing its best to keep up, informed me that the vertical vector of our climb was, stunningly, more than a mile a minute.

Intellectually I knew that the speeds and operating altitudes of the Lear were old hat, for jets had been going far faster and higher for decades, yet the visceral reality of those first flights created a burning excitement that penetrated every level of my being, so much so that it would take me hours for the euphoria to drain away after the trip. On the first flight in the right seat, as we cruised at FL450 (45,000 feet, the max legal altitude for the airplane and where we routinely flew to minimize fuel burn). I, who held an ATP, was so effectively mesmerized by the concept of being that far above the planet that I was unable to utter the simple phrase, "Flight Level 450," in response to an altitude query from ATC, managing only after a number of stammers and halts to utter, "forty-five hundred feet." I thought the captain was going to hurt himself laughing at the rube to his right.

As I came to know the airplane the captain I most often flew with, who also owned the company, and whom I'll call "Ben," would put me in the left seat every other leg. He wasn't being generous; he was tired and utterly pragmatic.

Gear Up and Good Night

Once he was reasonably certain I wouldn't kill him, Ben engaged in what had come to be called "gear up and good night." Going through about 10,000 feet following takeoff the copilot's workload dropped off to talking occasionally on the radio. Thus, because we so often ignored crew duty time limits and kept flying so long as there was freight to be hauled, we were frequently deeply tired, so upon passing through 10,000 it was not uncommon for the right-seater to unbuckle and head aft to spread out the sleeping bag wherever there was room, and fall asleep instantly upon becoming recumbent. Invariably the pressure change during the descent would wake him up at about 15,000 feet or so and he'd be buckled in and ready to take over copilot duties when descending through 10,000 feet.

Even when things settled into what passed for a routine, there were events, good, bad and funny, that made each trip its own adventure. Once, when light on fuel, we broke ground at O'Hare and passed through 10,000 feet exactly one minute later, a rate of climb of nearly two miles per minute.

Ben carried an HP calculator that could provide great circle routes from latitude and longitude inputs. Coming out of Van Nuys for Willow Run one night I asked Los Angeles Center for "060 degrees, direct Detroit."

When I was asked if we were carrying inertial nav, I said we had Hewlett-Packard. We were cleared direct Detroit. We made it, too, but with maybe enough fuel to go around the pattern once after a balked landing.

There was the 3:00 in the morning flight out of Fairfax (Kansas City, now closed) bound for Teterboro. I was cleared to fly a heading until receiving Cleveland, then direct Cleveland. With Captain Ben asleep in back, I dutifully flew the assigned heading, vainly waiting for the "off" flag on the VOR head to disappear and the needle to come alive. After some time Center asked me where I was going. I confidently read back my clearance, only to hear a laconic voice respond with, "You're over Joliet." I was so tired I'd put the wrong frequency in the nav radio. I shuddered to think what would have happened had I been on an approach where there were things to hit.

There were all sorts of creative electronic warning noises to alert the crew to the fact that all was not right in their little world aloft. I slowly learned where to look for information when one of the high decibel alerts activated. When I heard the noxious beeping akin to the French fries being done at McDonalds, I knew that I'd let the speed slide a little over the barber pole on descent. A "bing!" alerted me to wandering off altitude.


Then, one morning, again at about 3, when I thought I'd heard all the noises the airplane could generate, I was trying to move a bit to ease the discomfort of being 6 feet 4 inches tall in a cockpit built for smaller humans when I heard a sharp "Yelp!" Adrenalin poured into my system. I urgently scanned the panel trying to figure out what was wrong, what system was malfunctioning, and what I must do to set things right. What goes "Yelp!?" All needles were firmly where they should be.

I had to find what was wrong because at FL450 any problem can become huge in a frighteningly short time. Nothing. All seemed in order. I pulled the flashlight from its holder and started a complete exam of the cockpit. Its light revealed Ben's small dog, who frequently rode with us, curled up, asleep, around the base of the left hand control column. As I'd stretched, I'd inadvertently kicked him and he'd given a single, loud announcement of my transgression before going back to sleep.

Ben's dog was the source of enjoyment for us, as he had a universally pleasant personality. He never fussed when the flying pilot would err and have to shove forward on the yoke to avoid blowing through an assigned altitude and float him off the floor. He would not bark, just start running as fast as he could in midair, which usually caused him to invert (I never figured out why). Whomever was in the right seat would reach out and cradle him to his chest until gravity returned, and then set him gently between the seats.

There was, however, the night we stopped for fuel at Flower Aviation at Pueblo, Colorado while carrying eight, count 'em, eight Camaro door panels from Cincinnati to Van Nuys. Any Lear looks great from outside. The scantily clad line woman waved us into parking as Ben advised me that on a fill up for a jet, Flower gave the crew a box of steaks. As we shut down the young lady spread a red carpet in front of the door. I went back and opened it. When she saw that the guy coming out of the airplane and asking that it be topped off looked to be a bearded reprobate in a lumberjack shirt, blue jeans and boots and who certainly had no business in a Learjet, her welcoming smile disappeared. When Ben's dog jumped out behind me and relieved himself on the left main landing gear tires, she picked up the red carpet and drove away in her little golf cart. While we were fueled, we never did get our steaks.


There was terror as well: Late night over the Grand Canyon, again at FL450, above a thunderstorm, Ben asleep in the back, and sudden, sharp turbulence that caused both the autopilot and the yaw damper to shut off. A Lear at FL450 without a yaw damper will yaw in one direction while rolling in the other and then reverse itself with the magnitude increasing (true Dutch Roll). It is akin to being in a very bad skid on ice, in slow motion, in three dimensions. Unless you have received training for handling it, there is a good chance of loss of control of the airplane. I had not received such training.

I shouted for Ben. He couldn't hear me. My control inputs did not seem to be helping the situation and I suddenly couldn't recall where the yaw damper switch was. Good grief, I'd only been turning it on after takeoff for some time now, but as I'd turned the lighting down to enjoy the light show from the thunderstorm, I couldn't find the switch. The combination of fatigue, increasing terror and that I was used to activating the switch from the right seat did not help my increasingly frenetic search. I realized I had to go to plan B because I couldn't find the damn switch.

I turned on the autopilot, hoping it would fly the airplane better than I. Things got better, as the oscillations were not as profound. The autopilot was a model that had indicators showing the actions of its control servos. I could see those indicators moving nearly to their limits. I didn't think that was a good thing. I had to find the yaw damper switch. I grabbed the flashlight, turned it on and pointed it where I thought the yaw damper switch lived. The light made the difference. I found the switch and flipped it on. Instant return to sanity. The rudder pedals were again seemingly encased in concrete, the fear-inducing roll-yaw coupled cycle stopped and the Lear was serenely cruising the heights. It took some time for my pulse to return to double digits.

I was luckier than some of my contemporaries who went to work for companies that had either no scruples whatsoever, or no understanding of high-speed aerodynamics combined with high-altitude meteorology. Those operators were the ones who put "go fast switches" under the panel of their Learjets. The switch disabled both the overspeed warning and stick puller. 20-series Learjets have so much power that they can exceed redline airspeed in cruise flight. Doing so is an exceedingly serious affair because at some speed past redline comes what is known as "Mach tuck." When that happens the airplane begins to pitch down, eventually uncontrollably, until it violently comes apart. There is a very limited time for a well-trained crew to take precisely the correct action to save the airplane and themselves. While I was flying as copilot there were some inflight breakups of Learjets, notably freighters. It was later discovered that go fast switches were to blame in at least some of those tragedies.

It was a time of certain adventure, generated by characters behaving as humans will when the police is not watching. I was lucky. There were too many deaths and too many publicized close calls for that time to have been sustainable. As the Marshalls came in and cleaned up the wild west, the FAA eventually paid attention to the smaller operators at Willow Run, although it was not until after the Michigan economy had undergone one of its periodic collapses, this time in the winter of 1978-1979, and Ben's company went under.

When the FAA started inspecting for real, one operator had to junk some half-dozen 20-series Lears because it had never conducted required maintenance and the cost to make them airworthy exceeded their value. A lot of pilots found themselves facing violation actions. It took a few more years before the cowboy days ended. Flying with another operator, Ben died about that time in what I always thought was purely a fatigue-induced event. It was a time of walking very close to the aeronautical edge even though a heck of a lot of us did not understand that the edge existed or where it was most of the time. The times the abyss suddenly made itself known to me were terrifying. Looking back at some of the events with the knowledge I have now sometimes causes me to break out in a cold sweat. I got lucky. Too many of my peers went over that edge.

Rick Durden holds an ATP with type ratings in the Douglas DC-3 and Cessna Citiaton and is a CFII. He is the author of The Thinking Pilot's Flight Manual or, How to Survive Flying Little Airplanes and Have a Ball Doing It, Vols 1 & 2.


Many years ago, as a student pilot sitting on the ramp at Kansas City Downtown Airport, I was in the plane with my instructor listing to "information whiskey" on the ATIS recording when we heard a high-pitched squeal followed by laughter on the tape.

My instructor turned to me and said:
"Sounds like there's a little too much whiskey in the tower."

The we contacted ground control for more sober taxi instructions.

John Morris


Heard anything funny, unusual, or downright shocking on the radio lately? If you've been flying any length of time, you're sure to have eavesdropped on a few memorable exchanges. The ones that gave you a chuckle may do the same for your fellow AVweb readers. Share your radio funny with us, and, if we use it in a future "Short Final," we'll send you a sharp-looking AVweb hat to sport around your local airport. No joke.

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When I was listening to some of the presentations at the Sustainable Aviation Foundation symposium this week, it occurred to me that much of what I was hearing was simply an extension of the AUVSI event I covered earlier in the week. The lines between general aviation, manned aircraft in general and autonomous aircraft are being blurred. It's practically at the point that whether a person is aboard whatever thing happens to be flying is either incidental or irrelevant.

One of the most interesting presentations at SAF was by Parimal Kopardekar, a NASA manager who's neck deep in figuring out how the millions of drones that will soon choke the sky will be separated from each other and from manned aircraft. At last week's AUVSI event, I listened to Amazon's Gur Kimchi describe that company's vision of how its envisioned fleet of delivery drones will be managed and separated. I remember thinking after listening to his broad-brush treatment that for all their tech savvy, these guys don't have this figured out yet. Or if they do, they're not able to explain it. But Kopardekar added convincing detail and after his presentation, he told me NASA has been working with Amazon (and Google, I suspect) for years to develop the strategies that will segregate manned aircraft from drones and drones from each other. It's a complex problem and the solution, as Amazon's Kimchi described, will have to be overlapping and collaborative. It's wholly impractical to expect human controllers to have much of a role in this task, although they may have some. To a very large degree, the flying machines themselves will have to figure this out literally on the fly.

Kopardekar explained what he called UTM or unmanned traffic management as ultimately being cloud-based and largely autonomous and transparent to all users of the airspace. What that means is that it will be collaborative between air vehicles, whether manned or not, through sense-and-avoid technologies and onboard or cloud-based collision avoidance. What are the sense-and-avoid strategies? Good question. There are a number of technologies being tested, including laser and LIDAR-based methods and collaborative UAT-type communication between vehicles. After his presentation, I asked Kopardekar if ground-processed ADS-B would be a player. Probably not, he said. Too much spectral overload and lack of reliable reception at the low altitudes most UAS will inhabit. Segregation and "fence-in, fence-out" strategies will be part of this. It also suggests there may be some new technologies for light aircraft operating in drone-dense airspace. If Amazon's plan comes to fruition, the airspace could be dense enough in some places to preclude visual see-and-avoid. Suffice to say it's going to get very interesting in about three to five years.

Even if ADS-B has a secondary role here, it will have some role and some drones in some airspace will require ADS-B systems and/or transponders of some type. At AUVSI, I shot a brief video about a new startup that's building relatively inexpensive miniaturized ADS-B units that drones can carry. But the interesting thing to me is that they'll be targeting the experimental segment of general aviation with these devices. That's another example of convergence in which a man (or woman) in the cockpit is immaterial to the developmental task at hand. This company will be displaying at AirVenture and in addition to the video, which I'll get published next week, we'll do some more coverage.

In listening to presentations at a technical symposium like this, it's common to hear a mixed message. Researchers involved at the bleeding edge tend to assume that because they've eliminated--or see a way to eliminate--obvious technical barriers to a technology, it's thus ready for commercialization. But usually, they're not the ones doing the investment and figuring out the ROI. An example of this was a discussion of hydrogen fuel cell technology, which you can hear about in my podcast with Josef Kallo of Germany's DLR. I think commercially practical hydrogen fuel cells are more distant than he imagines, mainly for cost and marketability factors against traditional hydrocarbon fuels, which remain abundant and relatively inexpensive.  

Then there's the infrastructure problem. The facilities to produce and distribute hydrogen will need to be built and this is a very tall order if hydrogen is to become the equivalent of gasoline. Think about how easy it is to find a gas station or even an FBO with 100LL. In another SAF presentation, NASA chief scientist Dennis Bushnell, in a soaring tour of the technological horizon, said there were no barriers to a hydrogen infrastructure. While I agree that this is true technically, there's always the question of the Benjamins. Somebody has to convince an Exxon or a Shell (or a Google) to go big enough in hydrogen to reach critical mass and market viability. I'll be surprised if any company sees a workable market in hydrogen distribution just based on customer preference. As I've said before, it will take taxation or regulation based on climate concerns to make this market appealing for the near term. Petroleum-derived fuels are still too cheap and displacing them for purely altruistic reasons strikes me as a pipe dream.

Another interesting proposal using off-the-shelf technology was given by Cris Hawkins of Hawkjet. He showed a concept vehicle that's basically an aerodynamically low-drag pod with a pair of electric motors, a high-aspect-ratio wing and an energy-absorbing landing gear system. He calls this aircraft a V/ESTOL for Vertical/Extremely Short Take Off and Landing. Like others, Hawkins envisions an Uber-like on-demand air taxi system summoned by an app and operating entirely autonomously. Recognizing that vertical vehicles like the Velocopter I reported on at Aero require more energy for takeoff and climb than fixed-wing aircraft do, Hawkins is effectively splitting the difference, optimizing on the low drag of a high-aspect-ratio wing but giving it high-lift devices so it can get off a short runway. He thinks you'd need a bunch of pocket airparks to make it work.

Hawkins also gives these vehicles about 120 miles of range using current battery energy density. I think that's a little optimistic if you build in the kind of margins you'd want in a commercial transportation system, which his concept is intended to be. I think you'd need twice the current energy density, something like 300 wh/kg. Battery experts tell me that's at least 10 years off, if not closer to 20. Hybrids are another solution, of course, but I don't know if they work in this context. He also assumed quick change battery packs as a solution to low energy density. But at Aero, Pipistrel told me that even before its Alpha Electro was fielded in large numbers, customers have said they don't like the quick change idea and prefer to just plug the aircraft in for a recharge. Some are proposing to do the quick change robotically, but I can't help but think there's a limit to all this automation. It's a big investment for what may be a tiny revenue stream.

As far as the practicality of any of these ideas, they aren't there yet, but you can draw out the trend lines to make them viable. But ... not if they have to compete with hydrocarbon fuels on a level field. Unless hydrocarbon fuels become vastly more expensive by dint of scarcity, regulation or taxation, the electrics will struggle economically for the foreseeable future, which I think is about a decade. Beyond that, the technology and economics are, in my view, certain to make them niche players at first, then a significant part of the aviation ecosystem. People who think they'll never play a role make the mistake of assuming technology stands still and it never does. We'll see developments we never imagined possible. Motorola's Marty Cooper probably couldn't have foreseen the iPhone, but it sure as hell came to pass.

AKG Spring Special - Save $149 Instantly on the AV100

When Miles O'Brien moved to PBS, he discovered the world of tight budgets and MacGyvering equipment. He built his own drone to get aerial coverage for a Nova feature on flood protection and this year he hosted Exponential, the AUVSI convention in New Orleans. AVweb's Paul Bertorelli spoke with him at the convention.

A20 Aviation Headset || Now with Enhanced Features

Although there haven't been many accidents involving unmanned aircraft systems, there have been enough for the NTSB to begin building the investigatory resources to determine causes, just as they have for years with manned aircraft. In this exclusive AVweb podcast recorded at the AUVSI trade show in New Orleans, the NTSB's Bill English explains what's involved.

Jay Leno Installs an MVP-50 from Electronics International into His Eco Jet Car || Click to Watch

Hurray, hurray, the month of May,
Airborne folly starts the day,
You forget how significant a Convective SIGMET really is,
But memories revive in a rite of spring that begins by acing this quiz.

Click here to take the quiz.

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