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Volume 26, Number 22b
May 29, 2019
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NASA's Reno Drone Test a Winner
Marc Cook

Looking ahead to the day that the stalwart postman or Fedex driver is replaced by a package-carrying drone, NASA has been testing a “national traffic management system” for unmanned aerial vehicles (UAVs). The latest simulations took place in Reno, Nevada, where NASA tested the avoidance capabilities and other features of its UTM (short for Unmanned Aircraft Systems Traffic Management).

UTM combines the onboard hazard avoidance software in the UAVs along with a network of data providing “dynamic geofencing, severe weather and wind avoidance, congestion management, terrain avoidance, route planning and re-routing, separation management, sequencing and spacing, and contingency management.” As with ADS-B, the UAVs would share their location through the UTM to help provide separation.

“This activity is the latest and most technical challenge we have done with unmanned aerial systems,” said David Korsmeyer, associate director of research and technology at NASA’s Ames Research Center in Mountain View, California. NASA had tested the UTM in rural locations but this was the first opportunity to see how it worked in an urban environment, where the potential conflicts are greater and the challenges of controlling the UAV's path among buildings and other obstructions are significantly greater.

Prior to the Reno test, NASA described the mission: “Certified drone pilots will operate the aircraft in controlled areas of the city that are blocked to vehicle and foot traffic. The flights will simulate different scenarios involving multiple drones flying at once above city streets and between buildings. The researchers will collect data from the aircraft, drone pilots and commercial partners about the operation of the UTM system.”

Chris Walach, executive director of the Nevada Institute of Autonomous Systems, which is running the Reno tests, told The Associated Press that “when we began this project four years ago, many of us wouldn’t have thought we’d be standing here today flying UAVs with advanced drone systems off high-rise buildings.”

NASA says the Reno test was a success, and that this phase of the four-year program will continue in Reno and Corpus Christi, Texas, through the summer.

EAA, FAA Same-Page-It at Aviation Summit
Marc Cook

The EAA and the FAA carried out a two-day Recreational Aviation Summit at the association’s Oshkosh, Wisconsin, headquarters last week focusing on legislative matters important to recreational pilots. No doubt the 20 FAA officials attending were happy not to be talking about Boeing 737s.

"This summit is a unique, fruitful way to engage FAA policymakers on a focused agenda of matters that directly affect EAA members," said EAA CEO and Chairman of the Board Jack Pelton. "The willingness of FAA to include representation from many of its business units in the summit, even with the many current demands and challenges to the agency, is a continuing indication of its value and results.”

According to EAA, some of the topics covered included “living history flights, specialty aircraft examiners, and aerobatic flight issues including ADS-B support. There were also updates regarding the proposed MOSAIC (Modernization of Special Airworthiness Certificates) initiative.” Among other things, the MOSAIC initiative targets revisions to the operating limitations placed on experimental/amateur-built aircraft to bring them more into line with certified aircraft in terms of flight and maintenance limitations. It also seeks changes and clarity on the language surrounding experimental/exhibition licenses, under which many warbirds are flown.

While the association did not disclose specifics of the discussions, EAA’s vice president of advocacy and safety, Sean Elliott, said, "We took more than 20 action items from just these two days, and we'll review progress in just two months when FAA representatives are at EAA AirVenture Oshkosh. One of the best things about the annual EAA/FAA summit is that it sets a course for continued progress on issues that directly matter to EAA members.“

The association also said that “The EAA Flight Test Manual, released fall 2018, also received kudos from FAA officials. More than 2,000 of the manuals have already been obtained by pilots, setting a standard for safe, complete flight testing that can be used as a foundation for future projects.”

Two Citation Flameouts From DEF-Contaminated Fuel
Marc Cook

AOPA sent an alert to its members today reminding them of the hazards of contaminated jet fuel. Earlier this month, two Cessna Citation 550s landed safely after being fueled at the Punta Gorda, Florida, airport with jet fuel contaminated by DEF, which is an additive used in diesel fuel to reduce emissions in cars and trucks.

Both Citations were flown by Air Trek, an air ambulance operator at Punta Gorda. One was headed to Niagara Falls, New York, and suffered a double engine flameout but landed safely in Savannah, Georgia. The second Citation was destined for Chicago but landed in Louisville, Kentucky, with one engine shut down.

According to AOPA, “In August 2018, five aircraft were found to have been serviced with jet fuel containing DEF in Opa Locka, Florida. Nine more aircraft received fuel with equipment that had been exposed to DEF.” The previous year, 13 aircraft were serviced with jet fuel or equipment “exposed to DEF.”

Unfortunately for pilots, DEF is a clear, colorless liquid that cannot be detected. “There are no known pre-flight procedures pilots can use to identify the presence of DEF in jet fuel,” says AOPA.

DEF can cause crystalline deposits that clog fuel system components including filters and fuel nozzles. In the case of the aircraft receiving contaminated fuel in 2018, it was determined that the DEF was injected to the Jet-A supply at the fueling truck in place of the customary anti-icing additive.

For concerned turbine operators, AOPA recommends talking “with your fuel providers and ask if they use DEF in ground equipment. If so, inquire about procedures to confirm correct additives are used for jet fuel. This should include separate storage, clear labeling, confirmation of correct additives at the time of insertion, and training for personnel.”

United Extends Boeing 737 MAX Flight Cancellations
Marc Cook

Following the lead of American Airlines and Southwest Airlines, United has announced cancellations of flights intended to use the 737 MAX through Aug. 3. This is an extension of its previously announced plan to cancel flights through early July.

Some 2400 flights will have to be canceled in June and July alone for United, which operates 14 MAX aircraft. More than 3300 United 737 MAX flights have been canceled since the Boeing’s grounding in mid-March.

Boeing says that it has completed work on the software changes but the FAA has not yet approved them. Earlier reports had the MAX’s ungrounding by late June, but it’s clear that the airlines are playing conservative, especially when considering that these mothballed aircraft will need maintenance and relocation time before carrying passengers again.

Video: Bye Aerospace's eFlyer Electric Trainer
Paul Bertorelli

Bye Aerospace's new Eflyer electric trainer is just embarking on early test flights. AVweb recently visited the company's Denver-based factory and had a look at the new airplane. The company says it will be certified in about two years.

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It’s been nine years since the University of North Dakota Flying Team won the SAFECON competition, but don’t let that under-represent the team’s stellar track record. It has placed first or second in 30 of the last 36 competitions, hosted by the National Intercollegiate Flying Association (NIFA).

Made up of challenges ranging from “aircraft recognition to manually navigating cross-country flights,” SAFECON pits flying universities from across the country against each other in what is a friendly but ultimately intense six days of competition. “This was a total team effort,” UND’s head coach Lewis Liang said. “We had a young team that had to work hard after losing experienced upperclassmen. They knew it was a rebuilding year, and we asked them to do their best—they gave it their best this week.”

You can download the final results here (PDF), but some of the highlights include Southern Illinois University garnering the most points in the combined flight events categories while Embry-Riddle’s Prescott students topped the ground events categories. UND managed a very close second in both categories, which helped it land the overall prize. Ohio State’s Heather Atkinson won the CFI category. Purdue University’s Thomas Sherringham and David Tang crushed it in the CRM/LOFT (cockpit resource management/line-oriented flight training) category. UND’s Liang took home top honors as Coach of the Year.

To get a sense of the challenges these students faced and the joy the exhibited by landing at the top of the podium, take a swipe through the SAFECON awards banquet live-stream video below.

Some Myths Just Don't Fly
Paul Berge

We’ve all been there: Stabilized on final, gear and flaps down, passengers in their upright and locked positions, when out of the hemp rows pops a damn unicorn! And it doesn’t just run across the runway the way, say, a sensible dog might cross a freeway after computing the odds. Instead, it stops, turns and stares with its unic-horn pointing defiantly while it gives you that De Niro, You lookin’ at me? It’s the ADM moment you’ve trained for or at least mumbled a passable answer on your checkride.

Two types of pilots emerge from this scenario. If you said, “No such thing as unicorns,” then you’ll land and never tell another soul about what you think you saw. But, if you add power to go-around—delaying the pitch up just long enough to chase the unicorn off the runway—then you understand the importance of aviation mythology. Doesn’t mean you’re not crazy, just shows good ADM.

Aeronautical Decision Making (ADM) involves more than making the go/no-go call after listening to AFSS Alexa say, “Thank you for calling Lockheed-Amazon VFR Not Recommended Service. Where would you like to not go today?”

“Ah, Walleye, Minnesota …?”

“Excellent choice. Let’s see how we can discourage you ...”

AFSS does not make the go/no-go call for you, so here’s a flight planning tip: If you cancel a flight due to poor weather, it will improve. If, however, you launch despite portents of doom, the weather will deteriorate. That fact is from FAA-H-8699 Handbook of Aeronautical Mythology, which states, “The flipside of reality, mythology, is what makes the irrational plausible and aviation possible.” Beginning with lift itself.

Doesn’t matter if you’re a Bernoulli or Newtonian negative v. positive pressure proponent, lift isn’t real. Colorless, odorless and gluten-free, it happens solely because we believe in it. Like the Iowa Caucus. Lift Belief (LB) found me watching 1930s Hollywood films, wherein cool guys impressed sass-talking dames in unairworthy togs, with their abilities to lift above the earth. No need for science, aeronautical charm was based principally on pencil-thin mustaches and goggles. (Click here to express 21st Century outrage of 1930s gender type-casting.) Yeah, I had trouble dating in my teens. Nevertheless, I wanted to fly. Only problem was mythology’s dark side blocked the runway.

“It’s so expensive!” That whining phrase has smothered too many aviation dreams. I took my first flying lesson in California, a state of mind conceived in fantasy. It was 1973, and the airplane was an uninspiring Cessna 150, but when the instructor rode onto the ramp astride a Triumph 650, I knew we were in the presence of mythological greatness. He even wore goggles. I glanced around for a Jean Harlow but only saw a mechanic, who resembled Wallace Beery, struggling to pull a Cessna 172 with one of those cheesy tow bars that always slips off.

Admittedly, the naysayers, back then, had a point. Car gas was 35 cents per gallon, while 80 octane avgas was running almost twice that, meaning the flying club had to charge 70 cents for every 1/10thclick of the Hobbs meter, plus a few bucks to feed the CFI. The math just didn’t work. Neither did the tow bar, as the old mechanic—who was way younger than I am now—yanked it free, fell on his butt and swore Celtic oaths at the aviation gods, who, of course, are deaf to human complaints ... and ride unicorns.

“You know what a new Cessna 150 costs these days?” someone long forgotten asked me. I didn’t but soon learned. “A lot!” The blocker-of-all-things-fun answered and bolstered his assertion with irrelevant facts. “You could buy three new Ford Mavericks for what you’d pay for a single One-Fifty.”

Cessna 150s were ridiculously common back then, like Curtiss Jennies (JN-4s) in the 1920s, or Cessna 162 Skycatchers nowadays … Oh, wait, that fantasy never panned out. Anyhow, I recently walked up to a 150, admiring its deflated nose strut, and informed the owner, “I learned to fly in one of these.” She politely offered to take me back to the Old CFIs Home. Still, I’ve never gazed at a 1973 Maverick at the Pebble Beach Concours d’Elegance and said, “Yup, learned to parallel park in one of these babies.” Point is, flying is expensive and always was so don’t let anyone pop your dreams with that blunt stick of reality.

Likewise, eschew the fear mongers who chant, “It’s so dangerous!” Granted, it is. Everything’s dangerous. Obsessive adherence to safety can be dangerous, if it bores you to death. (Click here to earn WINGS credit by denouncing that assertion). We can quote stats, showing that aviation is safer than hand-feeding piranhas, but to what end? If you’re going to venture more than 10 feet above the earth, you’re at risk. Embrace and mitigate it or take up online canasta.

What about our mythical Big Brother? “The FAA’s not happy until you’re not happy,” or so the ramp saw goes. Except for its Aeromedical branch, that’s just nonsense. No one in the FAA is ever truly happy. I know. I worked for them and seldom felt the bliss, although I enjoyed being an air traffic controller. If the FAA hadn’t been involved, it would’ve been the perfect career. Still, no one in the FAA is out to ground you … well, again, see the Aeromedical exception.

Whatever your flight status, there’s always going to be a know-nothing eager to challenge your decisions. From learning in an old 150 to flying jump planes simply to build vertical flight time, someone—who probably doesn’t fly—will toss cold oatmeal on your imagination. Lift might exist, but no one knows why. We do know there’s always a unicorn waiting to challenge our beliefs, because People for the Ethical Treatment of Imaginary Beasts (PETIB) outlawed shooting the pests, and now they’re everywhere. But, hey, make up your own mind whether to land or go around what might or might not be real.

Truth In Icing

I received a call from the owner of a turbocharged, high-performance single who lives in the Great Lakes region, well-known for icing conditions in late autumn, winter and early spring. His airplane was equipped with an aftermarket TKS-style ice protection system and was not FAA-approved for flight in known icing (FIKI). The pilot wanted to discuss strategies for flight during the cold times of the year, including insights into conditions where icing layers are vertically thin and/or rates of ice accumulation are typically light (or even only a “trace”).

I kept circling back to the fact that his particular airplane was not FIKI-approved and that he does not have the authority to make a “quick climb” or “quick descent” through an icing layer, to take off when airframe ice is reasonably possible where he will fly, or to begin a descent and approach if the airplane ahead has reported even a trace of ice.

“Are you telling me I can’t fly my airplane in IMC at all in the winter?” the pilot fumed in response. “Yes, that’s exactly what I’m telling you,” I replied. The caller wanted me to support his airplane’s desired utility and teach him specific techniques for minimizing ice accumulation. I had to tell him that any ice at all is enough to cause him to divert, delay or cancel a flight, whatever it takes to remain away from “known ice.”

That call reminded me of rationalizations many pilots make about airframe ice they believe may legitimize flight in icing conditions in airplanes not certificated to do so. It also suggests some strategies of ice avoidance. Let’s look at some common ice rationalizations and seek the truth about airframe icing.

Keep Your Speed Up

The greatest hazard of airframe ice is the adverse and unpredictable effect ice has on aerodynamic surfaces. The wings and tail will be less effective with even small amounts of ice; further, since ice accumulation is not always symmetrical, there’s a strong likelihood the adverse effects will come unexpectedly, without warning. If airflow disruption is the biggest hazard, it seems reasonable that simply keeping your speed up will overcome the adverse effects and assure a safe landing with a load of ice. This rationalization is flawed.

In most airplanes, keeping the speed up with significant ice accumulation requires putting the airplane into a descent—sometimes a pretty dramatic one. One problem is the airplane may not have the control authority to recover from the descent when it comes time to land.

Secondly—and frequently overlooked in discussions of landing with a load of ice—forward visibility can be reduced to nil with only a very slight coat of frozen water. At night or in poor visibility, even small amounts of accumulation on the windscreen can distort visibility, making landing difficult. Regardless of the time of day, it’s very likely that you’ll have to resort to Lindbergh-style peripheral vision out the side windows to flare (such as it is with ice) and land.

Rationalizing that “speed saves” in ice is correct as far as keeping the wing flying. But keeping your speed up is not a reliable method of bringing an iced-up airplane in for a safe landing, especially on a typical GA runway. If ice is encountered, execute your preplanned “out” to remove it before you make an approach and landing requiring higher speed.

More Power Is Better

Rationalizing that it’s better to have extra power than to be able to remove ice, is a point. Extra power may allow you to climb through an icing layer (legally or not), but eventually you have to come back down. If you encounter icing in descent and/or on approach, the extra power won’t help.

Wet, slushy snow or volumes of clear ice can block an engine’s air inlet, reducing power. Alternate induction air sources typically are in the low-pressure area of an engine compartment. If the inlet air filter clogs with ice or snow, the alternate induction air pressure is low enough that the turbocharger may not provide full power. Some airplanes will experience reduced manifold pressure at full throttle when drawing induction air through the alternate air door.

Further, an iced-up propeller becomes less efficient at converting twist into thrust—it’s an airfoil, too—and the wings and tail become aerodynamic unknowns. What has been said about the effects of density altitude on airplane performance goes for airframe ice accumulation as well—you can’t turbocharge the propeller, wings or tail. Rationalizing that power overcomes ice does not hold up if the pilot is unable to escape to an area where ice is shed before descent and landing. By itself, turbocharging is not an ice-avoidance strategy.

A Small Chance Of Icing Is OK

One of the most significant advances in winter-weather risk management in the past few years is the introduction of the current icing potential (CIP) and forecast icing potential (FIP) briefing products. These charts respectively show the likelihood and anticipated intensity of ice accumulation. Some tablet-based flight planning software packages enhance the charts and break them down by altitude to make them even more usable. Some examples from are reproduced on the right.

I’ve found the forecast likelihood of airframe ice makes some pilots consider flight where the anticipated accumulation is “light” and the probability of encountering ice is low (less than 25 percent). It’s true that these conditions are less likely to result in a life-threatening ice encounter, but they are still icing conditions—something to avoid in airplanes not certificated for ice, and to be escaped from in a FIKI aircraft if accumulation begins.

'Known Ice' Means It’s Safe

Even in a “known-ice” airplane, vision may be severely limited by ice. At its best, a windshield “hot plate” deicer opens only a small rectangle for forward visibility. Often this clear zone is in the center of the windshield, not directly in front of the pilot.

Certification for flight in icing conditions has definite limits. It generally does not include approval for flight in icing conditions resulting from supercooled water droplets (common in cumulus clouds) or in freezing drizzle/ freezing rain. “Known ice” in the airplane’s limitations therefore does not mean the airplane is safe (or legal) to fly in any kind of airframe ice. What it does is provide the pilot with the option of legally attempting a flight in areas of suspected rime or areas of very limited clear or mixed icing.

Prudence dictates that the pilot have a clear, preplanned escape route into ice-free air even (or especially) if he/she intentionally exposes the aircraft to areas where airframe ice accumulation is likely. Rationalizing that “known-ice” airplanes can fly in any ice-laden air is true to a point. But it does not hold true if the pilot does not escape icing conditions if they are found.

So, yes, an airplane not certificated for flight in icing conditions is essentially prevented from flight in IMC for that portion of the year when air temperatures are likely to be near or below freezing at the altitudes the pilot wishes to fly. Strategies for avoiding ice include:

  • Flying only in VMC (whether under VFR or IFR).
  • Flying at altitudes that remain below the freezing level.
  • Flying in the warm air of an inversion with no precipitation or a cloud layer below with temperatures conducive to ice formation.

It’s surprising how frequently wintertime flights can be made using these strategies. Yes, it’s yet another level of hazard that impacts your go/no-go decision-making and just like thunderstorms in warmer times of the year, often it takes only a short delay or diversion to avoid the risk of airframe ice.

What Is Known Icing, Anyway?

To the extent there’s an FAA definition of known icing, it’s in this paragraph from a 2009 letter from the agency to AOPA:

Any assessment of known icing conditions is necessarily fact-specific. Permutations on the type, combination, and strength of meteorological elements that signify or negate the presence of known icing conditions are too numerous to describe exhaustively in [the FAA’s] letter. Whether a pilot has operated into known icing conditions contrary to any [aircraft] limitation will depend on the total information available to the pilot, and his or her proper analysis of that information in evaluating the risk of encountering known icing conditions during a particular operation. The pilot should consider factors such as the route of flight, flight altitude and time of flight when making such an evaluation.

The FAA lists these products, at a minimum, as those a “prudent” pilot would evaluate to determine there is no likelihood of airframe ice accumulation:

  • Surface observations [METARs]
  • Temperatures aloft
  • Terminal forecasts [TAFs]
  • Graphical weather (supersedes the discontinued Area Forecast)
  • Pilot Reports

Flying A 150-Knot Ice Cube

Way back in 2008, the FAA published a discussion of the safety challenges posed by flying in icing conditions. The full four-page document (PDF) is available online. One aspect of airframe icing explored was airplane certification and handling.

Stall Warning

“Prior to 1973, small airplanes were not...tested to the icing condition standard used today.... Small airplanes certificated prior to 2000 were given certification credit for natural aerodynamic stall warning (buffet) even if the airplane was equipped with a stall-warning system. Since ice buildup on the wing lowers the stall angle of attack, the stall-warning sensor might not provide warning in icing conditions.”


Pilots should treat their POH/AFM “recommended” minimum icing airspeeds as limitations. “If your POH/AFM does not have minimum icing airspeeds, add 15 to 20 knots indicated airspeed to your normal operating airspeed. This goes for all phases of flight, including approach and landing, where most small airplane icing accidents occur. Also, treat any buffet or vibration as an impending wing stall, and limit maneuvering in icing conditions.”


“Pilots should consider the climb performance of the airplane and the route’s minimum altitude when determining routes and exit strategies in preflight planning. The airplane’s climb performance will be degraded in icing conditions.” Changing altitude to warmer or drier air may get you out of icing. But “don’t assume you can climb with ice on your airplane.” Stay at or above the minimum icing speed and consider a 180-degree turn. You may need to enter a slight descent—trade altitude for airspeed—to remain above that speed.


Of course you wouldn’t knowingly take off with snow, ice or frost on the airframe, if for no other reason than it hasn’t been tested. “No airplane manufacturer, nor the FAA, has an established procedure for polishing frost, and the lift and drag penalties are unknown.... Make sure critical surfaces such as lifting surfaces, control surfaces, propeller blades, and engine inlets are free of contamination.”

Tom Turner is a CFII-MEI who frequently writes and lectures on aviation safety.

This article originally appeared in the December 2018 issue of Aviation Safety magazine.

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