Peter Garrison Archives - FLYING Magazine https://cms.flyingmag.com/author/peter-garrison/ The world's most widely read aviation magazine Wed, 11 Sep 2024 12:59:55 +0000 en-US hourly 1 https://wordpress.org/?v=6.6.1 Nothing Short of a Fatal Mismatch https://www.flyingmag.com/aftermath/nothing-short-of-a-fatal-mismatch/ Wed, 11 Sep 2024 12:59:52 +0000 https://www.flyingmag.com/?p=217365&preview=1 A Cessna 140 proved to be a goose among swans in a flock of dedicated STOL.

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In May 2022, a STOL Drag event took place at Wayne Municipal Airport/Stan Morris Field, (KLCG) in Nebraska. Training for novices would begin on Thursday and continue into Friday. Qualifying heats would be on Friday afternoon, and the races would continue through the weekend.

The contest, which typically occurs on grass or dirt areas parallel to paved runways, was to take place alongside Runway 5-23. 

On Friday afternoon the wind picked up. It blew out of the northwest across the STOL Drag course. Qualifying heats were postponed until the next day. 

A number of the competitors then decided to conduct an impromptu “traditional STOL” event, omitting the drag racing component. They would use the grass Runway 31, which was conveniently aligned with the wind. The pilots, organizers, and FAA inspectors who were present held a safety briefing, and the participants were divided into four groups of five or six aircraft to prevent clogging the pattern. The objective of the contest was to see who could come to a full stop in the shortest distance after touching down beyond the target line.

Each group completed two circuits without incident. Two groups had completed a third circuit, and now the third group was landing. The third airplane in that group was a modified Rans S-7, the fourth a Zenith STOL 701—unusual among the participants in having tricycle gear—and the last a Cessna 140. The S-7 landed, came to a stop in less than 100 feet, and taxied away. The 701 was still a fair distance out, and the 140 seemingly rather close behind it and low. 

A STOL Drag representative who was coordinating the pattern operations radioed the 140 pilot: “Lower your nose. You look slow.” The 140 pilot did not acknowledge. Half a minute later, the coordinator again advised the pilot to lower his nose. 

A few seconds later, the 140 yawed to the right, its right wing dropped, and with the awful inevitability of an avalanche or a falling tree, it rolled over into a vertical dive and struck the ground an instant later. A groan went up from the small crowd of onlookers. “Oh, my God, what happened!” one voice exclaimed. What had happened was all too clear—a low-altitude stall-spin that resulted in the pilot’s death.

The 140 pilot, 45, had an estimated 470 hours total time, more than 300 of which were in the 140. He had already qualified for STOL Drag competitions at a previous event.

The wind at the time of the accident was 15 knots gusting to 21. (As with all aviation wind reports, the 15 is the sustained wind and the 21 the maximum observed; no information is provided about lulls or wind speed variations below the sustained value.) The pilot of the 701 said that he had been maintaining about 50 mph (44 knots), as he had on several previous approaches, and that the wind on this approach felt no different than on the others. 

The 701 is equipped with full-span leading-edge slats, which make it practically incapable of unexpectedly stalling. Operating at a likely wing loading of less than 7 pounds per square foot, it could probably fly at around 35 mph. For the 701, an approach speed of 50 mph was conservative. The 140’s wing loading was only slightly higher, but its wing was not optimized for extremely slow flight. The 140’s POH stalling speed at gross weight was highly dependent on power setting, ranging from 45 mph power off to 37 mph, flaps down, with full power.

An FAA inspector who witnessed the accident reported his observations to a National Transportation Safety Board (NTSB) investigator. He noted that the 140 generally took longer to get airborne than other airplanes in its group, in part because the pilot, after first lifting the tail, rotated prematurely, so that the tailwheel struck the ground and the airplane continued rolling for some distance before finally becoming airborne. The pilot, he said, would climb steeply at first, but then have to lower the nose to gain speed. He appeared low and close behind the 701 on the last approach.

Earlier videos also showed that, on landing, the 140 rolled farther than other contestants, despite braking to the point of almost nosing over.

On previous circuits the pilot had used flaps, but on his last approach he failed to put the flaps down. The omission could account for the coordinator’s observation that the nose seemed high. Full flaps would have resulted in a more nose-low attitude.

The NTSB blamed the accident on the pilot’s obvious “exceedance of the airplane’s critical angle of attack.” It went on to cite as a contributing factor the “competitive environment, which likely influenced the pilot’s approach speed.” Since there were many knowledgeable observers of both the accident and of several previous takeoffs and landings by the 140, and everything was recorded on video from several angles, the NTSB’s diagnosis could probably have been even more specific and mentioned the failure to use flaps and the premature downwind-to-base turn.

If, by a chance misjudgment, the 140 pilot found himself too close behind the 701, he still had options other than slowing to the lowest possible speed. Since there was no one behind him, he could have gone around or made a 360 on final. The aircraft waiting to take off would have had to stand by a little longer, but only a fool would grumble because another pilot was being wisely cautious.

Instead, the 140 pilot chose to maintain his spacing by flying as slow as he could.

The decisive factor in the accident was most probably the failure to use flaps. It was almost certainly inadvertent. He probably forgot to put the flaps down, then believed they were down—because he had them down on the previous circuits—and chose his speeds accordingly. Adding flaps would have brought the stalling speed down 3-4 mph and also obliged him to use a little more power. Actually, it would have been quite a bit more because he was low, and the added power would have given him still more cushion.

The 140 was a goose among swans in this flock of dedicated STOL airplanes that possessed a near-magical ability to take off and land in practically no distance at all. Still, it was OK to be an outlier. The point of the contest was to have fun. You didn’t need to go home with a trophy—not that there even was one for this impromptu event.

But integrating an airplane with somewhat limited capabilities among more capable ones required special attention to speed and spacing. It would be easy to make a mistake. Once the mistake was made, and compounded by the failure to use flaps, all the pilot had left to lean on was luck—or willingness to recognize an error and go around while there was still airspeed and altitude to recover.


Note: This article is based on the National Transportation Safety Board’s report of the accident and is intended to bring the issues raised to our readers’ attention. It is not intended to judge or reach any definitive conclusions about the ability or capacity of any person, living or dead, or any aircraft or accessory.


This column first appeared in the July/August Issue 949 of the FLYING print edition.

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Peruvian Excursion Provides a Lesson in High Vapor Pressure https://www.flyingmag.com/flying-magazine/peruvian-excursion-provides-a-lesson-in-high-vapor-pressure/ Mon, 19 Aug 2024 13:02:46 +0000 https://www.flyingmag.com/?p=213464&preview=1 What is going to the airplane engine is more like froth than fuel.

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Lima, Peru, is overcast, as usual. We try to cancel IFR and turn on course once we’re on top, but the controllers insist on keeping us with them until Salinas, 40 miles down the coast. We finally cross Salinas at 12,000 feet and swing around northeastward. The Andes are close, rearing out of the stratus deck into a cloudless sky.

At 15,000 feet I notice that the fuel pressure is fluctuating. I watch the gauge intently. The tempo of the engine is unsteady. The fluctuations become larger and longer. 

The fuel selector valve and feed lines are under a floorboard beneath Nancy’s feet. I nudge her legs aside and remove the floorboard. I can see the fuel in the plastic lines on its way to and from the engine. Normally the flow to the engine is invisible, while the vapor return is full of bubbles. Now both lines are full of bubbles. What is going to the engine is more like froth than fuel. I switch tanks, and a moment later the engine goes silent. Boost pump—it roars back, hunts for a moment, then settles back to an unsteady rumble. Nancy has lifted her hands to her face in an instinctive gesture of fright. The mountains are close below us.

What’s wrong? Has a fuel line sprung a leak? But how can the lines from both tanks have gone leaky at once? Suddenly I recall being told that paper fuel filters could get clogged without appearing to be excessively dirty. They would gradually choke off the fuel supply, and the telltale sign would be a drop in fuel pressure. There are paper filters in the feed lines from both tanks. That must be it: Some impurity in the fuel has increased the resistance of the filters, and the engine-driven pump is pulling against the resistance, forming vapor.

Reluctantly, I turn back, call Lima Approach, and report an engine problem. It clears us direct, and we make the ILS approach. Below 10,000 feet the problem disappears, and I feel chagrin at having turned back.

On the ground, I check the fuel system. No leaks. I inspect the filter elements. They contain some lint and metal chips, mementos of the backyard construction of the wet wings, but  do not appear excessively dirty. I discard them anyway, leaving the filter shells empty. 

After two hours we’re back in the air. Now we’re both watching the fuel pressure. Above 10,000 feet it begins to fluctuate and gets steadily worse as we climb. There has been no improvement. But there is also nothing I can do that I have not already done. We level out at 19,000 feet.

In the hours we’ve wasted, clouds have built up over the mountains, but they are conveniently placed on either side of our route, as is often the case, because the clouds form first over the peaks while the routes follow the passes. We pass the beacons of Oyon—a small town nestled in a valley on our left—and Huanuco. The mountains fall away. Clouds are building on the eastern slope. We turn gradually toward the north over Tingo Maria and Tarapoto. Our last radio contact is with Tarapoto: shouting and static, thanks, goodbye.

The mountains behind us, we descend to 12,000 feet. The fuel pressure is a little steadier here, but its misbehavior has left me with a lingering distrust. We are over the headwaters of the Amazon River. I take a heading from the chart, which is now a blank interrupted only by an occasional blue line of latitude. Half an hour later, a huge, sinuous serpent of a river comes into view. It is the Marañon, but I cannot tell where along it we are.

It will be hundreds of miles before we encounter another positive landmark. Ahead of us the sky is creamy and, close to the horizon, ominously dark. I feel the quiet, suspended unease that sometimes comes upon me over ocean or forest, or in darkness over mountains in this homemade single-engine plane.

There is nothing to do but hold heading and wait. Time creeps by. The fuel tanks switch automatically every few minutes. The trees, which I can discern only with difficulty through 3 kilometers of haze, look low and flat in their billions, a dense blue-green canopy under which brilliant parrots shriek; myopic anteaters nose among rotten logs in solitary shafts of sunlight; monkeys pick lice from one another; jaguars sleep; giant blue butterflies fan their wings slowly on dripping vines; and snakes doze draped over smooth limbs. 

Perhaps the drone of our engine momentarily diverts the attention of a naked bowman. I know it’s all there. I’ve seen it in the movies. The sun disappears behind an anvil head. Soon we plunge into a wall of clouds. Rain showers clatter against the windshield. We break out, glimpse an anonymous river—is it the Urituyaco, Copalyacu, Corrientes, Tigre, Curaray or Tiputini?—and then collide with a new mountain of clouds.

In principle, we are heading almost due north and crossing a degree of latitude every 23 minutes. Each 23 minutes, therefore, I mark an estimated point on the folded chart. I suspect we may have drifted into Ecuador, but from our position the difference between Peru, where we are authorized to be, and Ecuador, where we are not, seems insignificant. We cross a big river full of silty islands: It must be the Rio Napo. We should be picking up the beacon at Tiputini, but we are not. 

A little later the ADF suddenly wakes up and points to Limoncocha in Ecuador. A moment later it finds Tarapoa, then Puerto Asis, and I am finally able to triangulate our position: on the equator, near 76 degrees west longitude. Then, on the right, an airstrip, settlement, river fork, island. Completely unsought and unexpected, the landmark offers itself with a helpful generosity that is as touching in inanimate objects as it is in strangers. It is Putumayo. We have entered Colombia.

The sun is setting as we cross the eastern cordillera. It briefly illuminates a sublime vista of cloud, cliff, valley, and river that deserves a double-page spread in a coffee-table book of Colombian landscape. We are making a good ground speed: 180 knots. Florencia passes beneath us, Neiva, and Girardot. Chocolate pours down from the mountains as we make the long straight-in approach to Bogotá.

A few days later, at the airport, I chat with a local pilot who is there, like me, to wrestle with the bureaucratic serpent of flight authorizations. I tell him about the fuel pressure problems I had on the way from Lima.

“Oh, yeah,” he says. “High vapor pressure. As soon as I get up into the mountains, I just turn on the boost pump and leave it on. The fuel here is crap.”


This column first appeared in the July/August Issue 949 of the FLYING print edition.

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Ultimate Issue: Analyzing a Fatal Final Turn https://www.flyingmag.com/pilot-proficiency/ultimate-issue-analyzing-a-fatal-final-turn/ Fri, 19 Jul 2024 12:56:58 +0000 /?p=211432 Van's RV-4 accident presents a tragic case study of the stall-spin scenario.

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In 1949, the Civil Aeronautics Authority (the precursor to the FAA), reacting to the number of training accidents involving spins, removed the spin from the private pilot syllabus. Some pilots who knew how to spin an airplane suspected that anyone who didn’t wasn’t really a pilot.

Cooler heads observed that the majority of unintentional spins occurred in the traffic pattern, particularly on the base-to-final turn, where there was no room to recover even if the pilot knew how to. So knowing how to spin and recover served no purpose, besides its entertainment value—which, to be sure, was considerable.

Under the new dispensation, pilots were taught, in theory at least, not how to recover from a spin but how to avoid one. Nevertheless, stall spins, usually in the traffic pattern, still account for more than a tenth of all airplane accidents and around a fifth of all fatalities. Because they involve a vertical descent, stall spins are about twice as likely to be fatal as other kinds of airplane accidents.

Why has the FAA’s emphasis on stall avoidance not done more to reduce the number of stall spin accidents? There are probably many reasons, but I think the lack of realism in the training environment deserves some blame. The training stall is a controlled maneuver, briefed in advance, approached gradually, calmly narrated, and recovered from without delay. The real-life, inadvertent stall is sudden, unexpected, and disorienting.

The pilot does not see it coming and so does nothing to prevent it. The training stall is so reassuring that pilots fail to develop a healthy fear of the real thing. After this preamble, you may guess that I am going to talk about a fatal stall spin.

The airplane was a Van’s RV-4, an amateur-built two-seat taildragger with a 150 hp Lycoming engine. It had first been licensed 13 years earlier and later sold by its builder to the 48-year-old pilot, a 1,300-hour ATP with single- and multiengine fixed-wing, helicopter, and instrument ratings. For the past six months, the pilot had been on furlough from regional carrier Envoy Air, where he had logged 954 hours in 70-seat Embraer ERJ-175 regional jets.

On the day of the accident, he added 24 gallons of fuel to the RV and flew from Telluride (KTEX) to Durango (KDRO), Colorado, a 25-minute trip, to pick up a friend. They then flew back to Telluride, where the temperature was 1 degree Fahrenheit, and a 10-knot breeze was blowing straight down Runway 27. The density altitude at the runway was about 9,600 feet.

Entering a wide left-downwind leg at about 100 knots, the pilot gradually decelerated and descended. By the time he began his base-to-final turn, he was about 200 feet above the runway and was going to slightly overshoot the extended centerline if he didn’t tighten his turn. His airspeed dropped to 50 knots, and the airplane stalled and spun. An airport surveillance camera caught the moment—a blur, then a swiftly corkscrewing descent. It was over in a few seconds. Both pilot and passenger died in the crash.

The National Transportation Safety Board’s finding of probable cause was forthright, though it put the cart before the horse: “The pilot’s failure to maintain adequate airspeed…which resulted in the airplane exceeding its critical angle of attack…” Actually, the opposite happened: The pilot allowed the angle of attack to get too large, and that resulted in a loss of airspeed. It was the angle of attack, not the airspeed, that caused the stall.

Still, it was an airspeed indicator the pilot had in front of him and not an angle-of-attack indicator, so to the extent that the pilot was consciously avoiding a stall, he would have had to use airspeed to do so. 

The published stalling speed of the RV-4 at gross weight is 47 knots. In a 30-degree bank, without loss of altitude, that goes up to 50.5. Individual airplanes may differ.

But in any case it’s misleading to make a direct, mathematical link between bank angle and stalling speed, although the NTSB frequently does just that. When you perform a wingover, your bank angle may be 90 degrees, but your stalling speed is certainly not infinite. In the pattern, you can relieve the excess G-force loading associated with banking by allowing the airplane’s downward velocity to increase—assuming that you have sufficient altitude.

On the other hand, with your attention focused on the simultaneous equations of height, position, glide angle, and speed that your mental computer is solving in the traffic pattern, you may not even be aware of a momentary excursion to 1.2 or 1.3 Gs.

The RV-4, with a rectangular wing of comparatively low aspect ratio and no washout, stalls without warning in coordinated flight but is well-behaved and recovers readily. Uncoordinated, it can depart with startling abruptness. It resembles all other airplanes in being less stable when the center of gravity is farther aft, so maneuvering at a speed just a few knots above the stall may be more perilous when there is a passenger in the back seat. Like most small homebuilts, the RV-4 is sensitive to fingertip pressure on the stick and easily overcontrolled.

The NTSB’s report on this accident does not include any information about how many hours the pilot had flown the airplane or how many of those were with a passenger. The FAA registry puts the cancellation of the previous owner/builder’s registration just one month prior to the accident, suggesting the pilot may not have had the airplane for long.

The pilot never stabilized his approach. He descended more or less continuously after entering the downwind leg several hundred feet below pattern altitude—to be sure, the pattern at Telluride is 400 feet higher than normal—and never maintained a steady speed even momentarily. His speed decreased more rapidly as he entered the final turn, perhaps because he felt he was a little too low and instinctively raised the nose. Besides, the terrain rises steeply toward the approach end of Runway 27, possibly making him feel he was descending more rapidly than he really was.

A final factor that may have played a part in this accident is the altitude. The runway elevation at Telluride is at about 9,100 feet. Density altitude doesn’t matter for speed control in the pattern if you pay attention to the airspeed indicator, because all the relevant speeds are indicated airspeeds. But your true airspeed, which is 10 knots greater than indicated, can still create the illusion that you have more speed in reserve than you really do when you are making a low turn to final.

There’s a reason that students are taught to establish 1.3 Vs on the downwind leg, begin the descent abeam of the threshold, and maintain a good speed margin throughout the approach. It helps keep the stall-spin numbers down.


Note: This article is based on the National Transportation Safety Board’s report of the accident and is intended to bring the issues raised to our readers’ attention. It is not intended to judge or reach any definitive conclusions about the ability or capacity of any person, living or dead, or any aircraft or accessory.


This column first appeared in the Summer 2024 Ultimate Issue print edition.

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Ultimate Issue: AOA Gets Revisited—Again https://www.flyingmag.com/voices-of-flying/ultimate-issue-aoa-gets-revisited-again/ Mon, 08 Jul 2024 13:13:20 +0000 /?p=210816 Designing an accurate angle-of-attack system represents only half the challenge.

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For as long as I can remember—I started doing this in 1968—writers for FLYING and other aviation publications have been singing the praises of angle-of-attack (AOA) indicators.

They were rare in general aviation airplanes until 2014 when the FAA simplified the requirements for installing them. A proliferation of aftermarket AOA systems followed, ranging in price from around $300 to more than $3,000. I don’t know how widely these devices have been adopted, nor do I know whether any study has been made of their impact on the GA accident rate.

Despite its well-known shortcomings as a stall-warning device, the airspeed indicator remains the only AOA reference in most airplanes. It has the advantages of being a mechanically simple system, intuitive, and familiar. Speed is an everyday experience, while angle of attack, for most pilots, remains in the realm of the theoretical.

Theoretical or not, I think, to start with, that we could improve the terminology. “Angle of attack” is really a proxy for something else, namely “the amount of the maximum lift available that is currently in use.” So it would be more meaningful to speak of a “lift indicator,” “relative lift indicator,” or “lift fraction indicator.”

One of the advantages of thinking in terms of lift fraction is that almost all of the important characteristic speeds of any airplane—the exceptions are the nonaerodynamic speeds, such as gear-and-flap-lowering speeds—fall close to the same fractions of lift regardless of airplane size, shape, or weight. Best L/D speed is at around 50 percent and 1.3 Vs at exactly 60 percent. Stall, obviously, is at 100 percent. A lift gauge is universal: It behaves, and can be used, in the same way in all airplanes.

A few years ago, in a column titled “A Modest Proposal,” I suggested demoting the hallowed airspeed indicator to a subsidiary role and replacing it with a large and conspicuous lift indicator. I borrowed the title from a 1729 essay by Jonathan Swift, the author of Gulliver’s Travels, in which he satirically proposed that poverty in Ireland might be relieved if the populace were to sell its manifestly too numerous babies to be eaten by the rich. My appropriation of Swift’s title was meant to suggest that I considered my proposal was about as likely to be adopted as his.

At the time I wrote my article, I was not yet aware of a 2018 paper by a team led by Dave Rogers, titled “Low Cost Accurate Angle of Attack System.” Using a simple underwing probe and electronic postprocessing, Rogers and his group achieved accuracy within a fraction of a degree of angle of attack with a system costing less than $100. That’s more accuracy than you really need, but better more than less.

The low cost is made possible by the availability of inexpensive small computers— Rogers’ team used a $20 Arduino—that can be programmed to do the math needed to convert the pressure variations read by a simple probe into usable AOA data. Processing is necessary because the airplane itself distorts the flow field around it and makes it all but impossible to read AOA directly with a vane or pressure probe situated close to the surface of the aircraft. Besides, configuration changes, like lowering flaps, alter the lifting characteristics of the wing.

Designing an accurate system is only half the challenge, however. There is also the problem, perhaps even more difficult, of how best to present the information to the pilot. Little agreement exists among current vendors. Some presentations use round dials, some edgewise meters, some various arrangements of colored lights or patterns of illuminated V’s and chevrons resembling a master sergeant’s shoulder patch.

In 1973, the late Randy Greene of SafeFlight Corp. gave me one of his company’s SC-150 lift indicators for my then-just-completed homebuilt, Melmoth. The SC- 150 used a rectangular display with a moving needle. There was a central stripe for approach speed flanked by a couple of dots for climb and slow-approach speeds, and a red zone heralding the approach of the stall. The probe that sensed angle of attack was a spring-loaded, leading-edge tab, externally identical to the stall-warning tabs on many GA airplanes.

Apparently, some people mounted the SC-150’s display horizontally, but that made no sense to me at all. Given that I wanted it vertical, however, Greene and I did not see eye to eye about which end should be up. Greene was a jet pilot used to a lot of high-end equipment (SafeFlight made autothrottles, among other fancy stuff, for airliners). He understood the device as a flight director—as you slowed down, the needle should move downward, directing you to lower the nose.

I, who despite having acquired in my younger days a bunch of exotic ratings, am really just a single-piston-engine guy, saw it as analogous to an attitude indicator and thought that as the nose went up the needle ought to do the same. Greene saw the display as prescriptive; I saw it as descriptive.

Recently, Mike Vaccaro, a retired Air Force Fighter Weapons School instructor, test pilot, and owner of an RV-4, wrote to acquaint me with FlyONSPEED.org, an informal group of pilots and engineers working on (among other things) practical implementation of a lift-awareness system of the type described in Rogers’ paper. The group’s work, including computer codes, is publicly available. Its proposed instrument can be seen in action in Vaccaro’s RV-4 on YouTube

The prototype indicator created by the FlyONSPEED group mixes descriptive and prescriptive cues. Two V’s point, one from above and one from below, at a green donut representing approach speed, 1.3 Vs, the “on speed” speed. The V’s are to be read as pointers meaning “raise the nose” and “lower the nose.” An additional mark indicates L/D speed. G loading, flap position, and slip/skid are also shown on the instrument, along with indicated airspeed.

Importantly, the visual presentation is accompanied by an aural one. As the airplane slows down, a contralto beeping becomes more and more rapid, blending into a continuous tone at the approach speed. If the airplane continues to decelerate, the beeping resumes, now in a soprano register, and becomes increasingly frenetic as the stall approaches. Ingeniously, stereo is used to provide an aural cue of slip or skid—step on the rudder pedal on the side the sound is coming from. The audio component is key: It supplies the important information continuously, without the pilot having to look at or interpret a display.

This system—it’s just a prototype, not a product—is pretty much what my “modest proposal” was hoping for, lacking only the 26 percent-of-lift mark that would indicate the maneuvering speed. Irish babies, beware.

Now I just have to figure out what we’ll do with all those discarded airspeed indicators.


This column first appeared in the Summer 2024 Ultimate Issue print edition.

The post Ultimate Issue: AOA Gets Revisited—Again appeared first on FLYING Magazine.

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A Cautionary Tale About Pilot Freelancing https://www.flyingmag.com/pilot-proficiency/a-cautionary-tale-about-pilot-freelancing/ Tue, 25 Jun 2024 13:04:25 +0000 /?p=209814 Fatal Saratoga accident shows that some destinations aren’t worth making.

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In late June 2020, a 40-year-old oil industry entrepreneur and executive left David Wayne Hooks Memorial (KDWH) near Houston alone in his Saratoga. Helped by a tailwind, he arrived over his destination—a private strip 90 miles to the northeast—36 minutes later.

It was about 1 o’clock in the morning. The air on the surface was warm and humid. If he checked the weather—there was no evidence that he did—he would have expected to find widespread but patchy cloudiness over the route of flight and at the destination. In some places clouds were broken or scattered with tops at 3,000. Elsewhere buildups climbed into the flight levels. Ceilings and visibilities under the clouds were good, at worst 700 feet and 5 miles. The temperature and the dew point were only 3 degrees apart, however, and there was a slightly increased risk of fog formation owing to, of all things, particulate pollution from dust blown in from the Sahara.

During the short flight, he climbed to 3,600 feet, probably to get above some cloud tops. It was pitch-dark as the crescent moon was far below the horizon. As he neared his destination he descended to 1,500 msl, 1,300 feet above the terrain, and reduced his groundspeed from 175 knots to 100 knots.

The airstrip at which he intended to land was 3,500 feet long, 40 feet wide, and had a light gray concrete surface oriented 4/22. Other than a hangar on an apron at midfield, there were no structures on the airport and no edge lights along the runway.

The only lights were red ones marking the runway ends. The surrounding area was largely dark. Sam Rayburn Reservoir sat close by to the north and east, a vast region of uninterrupted black. Parallel to the runway, about half a mile north, was State Highway 147, lighted only by the headlamps of infrequently passing cars.

For almost an hour, the pilot flew back and forth over the airstrip, tracing a tangled path of seemingly random right and left turns. His altitude varied between 350 and 1,100 feet agl and his groundspeed between 65 and 143 knots. His ground track, as recorded by ATC radar, suggested no systematic plan, but it was broadly centered on the northeast end of the runway.

The last return from the Saratoga, recorded 54 minutes after it arrived over the field, put it 9,700 feet from the northeast end of the runway on a close-in extended left downwind leg for Runway 22 at a height of 350 feet agl and a groundspeed of 94 knots. The Saratoga was below radar for the remainder of the flight.

Its burned wreckage was found at the southern edge of the clear-cut area surrounding the runway, several hundred feet short of the threshold. A trail of parts led back across the clear-cut to its north side, where the airplane had clipped a treetop at the edge of the woods. From the orientation of the wreckage path, it appeared that the Saratoga may have overshot the centerline on base and was correcting back toward the approach end lights when it struck the tree.

In the course of the accident investigation, it emerged that the airplane was out of annual, its last inspection having occurred in 2017, the registration had expired, and the pilot’s medical was out of date. The pilot had 400 hours (estimated) but did not have an instrument rating and, in fact, had only a student certificate. The autopsy turned up residues of amphetamine, methamphetamine, and THC (the psychoactive component of cannabis), but investigators did not rule out the possibility that the drugs could have had a therapeutic purpose.

The National Transportation Safety Board’s report on the accident declines to speculate on whether the drugs impaired the pilot in any way. In fact, the NTSB report concedes that “the pilot’s aircraft handling was not deficient relative to his limited experience of flying in night instrument conditions and the prolonged period of approach attempts.” The finding of probable cause cited only the pilot’s “poor decision-making as he attempted to land at an unlit airstrip in night instrument conditions.”

The pilot bought the Saratoga in 2016 and then took flying lessons, but he stopped short of getting the private certificate. His instructor said he had never given him any instrument training. The pilot’s wife said that he “normally” flew to the airport at night and circled down until he could see the runway.

The airport was in Class G airspace. What the cloud conditions were we don’t know—the nearest automated reporting station was 24 nm away—and so we don’t know whether the Saratoga was ever in clouds and, if so, for how long. Maneuvering around at low level for nearly an hour in darkness and intermittent IMC would be taxing even for many instrument-rated pilots, and so it seems likely that if the pilot was in clouds at all, it was only for brief periods.

Two things strike me about this accident. First, how close it came to not happening: If the pilot hadn’t clipped the tree, he might have made the turn to the runway successfully and landed without incident, as he apparently had done in the past. Second, that he had ever managed the trick at all. I can only suppose that the contrast between the runway clear-cut and the surrounding forest was discernible when there was moonlight and that he was able to use GPS and the runway’s end lights to get himself to a position where his landing light would illuminate the runway.

Rugged individualism being, supposedly, an American virtue, I leave it to you to applaud or deplore the nonconformist aspects of this pilot’s actions. Perhaps a certain amount of freelancing is inevitable in an activity like flying. But I deprecate his persistence. One of the essential arrows in every pilot’s quiver should be knowing when to quit. He set himself a nearly impossible goal, and after flying half an hour to his destination, he spent an hour trying to figure out how to get onto the ground.

If it was that difficult, it wasn’t worth doing. There were other airports—with runway lights—nearby.

At the time of the crash, the pilot was awaiting the decision of a Houston court in a wrongful  termination lawsuit that he had filed against a former employer. Five months later, the court found in his favor to the tune of $143 million. Thanks to a terminal case of “get-homeitis,” however, he wasn’t there to enjoy it.


Note: This article is based on the National Transportation Safety Board’s report of the accident and is intended to bring the issues raised to our readers’ attention. It is not intended to judge or reach any definitive conclusions about the ability or capacity of any person, living or dead, or any aircraft or accessory.


This column first appeared in the May 2024/Issue 948 of FLYING’s print edition.

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Two Fatal Cases of the Simply Inexperienced https://www.flyingmag.com/pilot-proficiency/two-fatal-cases-of-the-simply-inexperienced/ Mon, 27 May 2024 14:00:00 +0000 /?p=208062 NTSB reports blame a pair of aviation accidents on green pilots.

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In September 2019, in a sparsely populated part of South Dakota near the Nebraska border, a father and son went flying in their Cessna 140. When they did not return, sheriffs began a search.

The next day, the wreckage of the 140, its front end crushed, was found a few hundred feet northwest of the pilot’s private strip. Since the flaps were down, it had evidently been approaching to land when it stalled and spun. There was no way to know why the mishap occurred, but the National Transportation Safety Board (NTSB) report on the accident noted that conditions were such that carburetor icing was likely.

Stall spins are, and always have been, a common cause of fatalities in general aviation. They often occur during turns at the base-leg end of the pattern. What made this accident a little less usual than most was the history that led up to it.

According to the NTSB, the father, 39, was a student pilot. He had learned to fly from his grandfather, who had no pilot certificate at all. The father began logging time in 2007 and stopped in 2015. He got his last FAA medical in 2014 and his last fight review in 2015. He had a student endorsement for a Cessna 150 but none for the 140. The NTSB estimated his total time as 40 hours, of which 20 were as pilot in command and 20 were in the 140. These estimates were based, apparently, on the fact that the pilot used the 140 to survey local water towers from the air and report levels to their owners.

The CFI from whom the pilot had received some flight instruction—and who described him as a “safe pilot”—reported that the pilot knew he was not allowed to carry passengers with a student certificate, but he was “anti-regulation with the government.” The NTSB attributed the accident to the “student pilot’s noncompliance and lack of experience” but noted it was impossible to know who was at the controls at the time of the fatal stall. The father could have been upholding the family tradition by teaching his son to fly.

Three weeks after that accident occurred, a Cessna 421 crashed in a wooded area near the DeLand, Florida, airport (KDED), killing its three occupants. A couple of witnesses saw the airplane flying at low altitude. One, who spotted the airplane on two occasions 10 minutes apart, described the engines on the second sighting as sounding as if they were idling. Another witness reported hearing popping or backfiring sounds. The latter witness also reported the airplane rolled to the left three times before he lost sight of it behind the treetops. It’s not clear whether by “roll” he meant a full roll or, more plausibly, a wing dropping and then coming up again.

The NTSB concluded “it is most likely the pilot lost control of the airplane while maneuvering” and added that the “pilot’s lack of any documented previous training in the accident airplane make and model contributed to his inability to maintain control of the airplane.”

The pilot of the ill-fated 421 was a 500-hour SMEL CFI. His logbook lacked a “complex airplane” endorsement, but that was probably an oversight. A complex airplane is one with flaps, retractable landing gear, and a variable-pitch propeller. It would be difficult to earn a multiengine rating in an airplane without those features—there aren’t a lot of Champion Lancers left.

As pilots who have flown more than one type of airplane know, the actions required to keep them right side up are alike for all. This 500-hour CFI with 40 hours of logged multiengine time had managed to start the 421’s two GTSO 520s, taxi, take off, and fly for at least 10 minutes. He seemed to have demonstrated an ability to control the airplane.

The 421 had a somewhat checkered recent history. Its last annual inspection had been performed five years earlier, and its Hobbs meter had advanced only four hours in the meantime. Its previous owner had put it up for sale on eBay, and a Texas man had bought it for $35,000, sight unseen, intending to spend a few thousand dollars having it restored to airworthy condition and then resell it. The 50-year-old airframe had, according to aircraft.com, 5,713 hours, and both engines were well short of TBO.

NTSB investigators found nothing to suggest the engines had failed, but the condition of the propeller blades indicated “low rotational energy at impact.” Fire destroyed all fuel tanks, and the NTSB report does not comment on the quantity or quality of fuel residues or the presence or absence of water or other sediment in the engines or what remained of the fuel system.

The Texas A&P whom the owner had engaged to travel to Florida and restore the airplane to airworthy condition had located a pilot to deliver it for $4,500. That pilot, 32, was in the right seat when the crash occurred. With a private certificate and 155 hours, he was even less qualified than the left-seat pilot to fly the 421. The owner declined the suggested pilot and instead gave the job to a certain instructor whose name he did not recall.

Most likely, this was the instructor who was flying the airplane when the accident happened. At the time of the accident the airplane had not yet been signed off by the A&P, and afterward everyone involved denied having any idea what the two pilots and their passenger were doing flying it. The NTSB speculated that the flight was probably of a “personal” nature—that is, a joy ride.

The NTSB blamed both of these accidents on inexperience. Although the South Dakota pilot owned his airplane and had flown, on and off, for a dozen years, his experience had been intermittent. The least one could say is that when the accident occurred, he was more experienced than he had ever been before. As for the other cause cited, noncompliance, it’s hard to see how it qualifies as a cause.

Plenty of experienced and compliant pilots stall and spin, and nobody says they did so because they were too experienced or compliant. In the case of the Florida crash, the NTSB cited the “pilot’s lack of training and experience in the accident airplane make and model.”

The analysis fails to even suggest the possibility of an external cause, such as, say, a partial power loss in the left engine. In fact, as an online bodycam video of the arrival of would-be rescuers at the accident site shows, the airplane came to rest right side up and was not severely fragmented.

Was it really out of control? Or was the pilot valiantly trying to cope with an emergency not of his own making?


Note: This article is based on the National Transportation Safety Board’s report of the accident and is intended to bring the issues raised to our readers’ attention. It is not intended to judge or reach any definitive conclusions about the ability or capacity of any person, living or dead, or any aircraft or accessory.


This column first appeared in the April 2024/Issue 947 of FLYING’s print edition.

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The Craft of Providing Variety in Airplanes https://www.flyingmag.com/voices-of-flying/the-craft-of-providing-variety-in-airplanes/ Thu, 13 Jun 2024 12:47:24 +0000 /?p=209303 Miles and Rutan found a way to master diversification in their designs.

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German novelist W.G. Sebald liked to salt his fiction with photographs. They illustrated his scenes so well that I had to wonder whether he staged the photos to match his text or shaped his story to match photos he happened to have.

In one of his books, Austerlitz, the title character goes flying at night with pilot friend Gerald Fitzpatrick in a “Cessna.” He describes the mesmerizing sight of the familiar constellations overhead. Now, looking up at the stars from an airplane is an entrancing experience, but no one ever had it in a Cessna.

The corresponding photograph, though somewhat distant and blurred, is clearly not of a Cessna but of a small twin-engine, twin-finned airplane that does, however, have a transparent canopy. I got the explanation for this apparent authorial fumble from a Swiss friend: Among nonpilots in Germany, “Cessna” would simply mean a private airplane, no particular brand.

The twin was actually a Miles Gemini, an airplane brought into being, like the original Beech Bonanza, by the anticipated postwar explosion in demand for personal air travel. It had four seats and was equipped with two 100 hp engines of the inverted in-line variety, housed in those nice narrow cowlings that many British and French aircraft of the 1930s and ’40s had. One of its unusual features was a big external airfoil flap.

Despite the flap, however, the published stalling speed of 35 knots cannot have been a calibrated airspeed—45 is more plausible.

Whatever its real landing speed, the fictional Gerald Fitzpatrick crashed fatally in his Gemini. His friend Austerlitz gloomily comments that this was bound to happen, since he was so fond of making sightseeing flights in the south of France.

Novelists just won’t give private planes a break.

I wondered how the 3,000-pound Gemini would do on one engine. Late designer John Thorp, contemplating a trip to Europe with his wife, Kay, once propped up a couple of small Lycomings in front of his two-seat Sky Skooter. His friend George Wing, creator of the ubiquitous Hi-Shear rivet, happened to walk in, and thus was conceived the Wing Derringer.

Wing was not taking any chances on O-235s, however. The two-seat Derringer, with 160 hp O-320s, could definitely climb on one engine. The question of how a twin with 100 hp engines climbs on only one was answered, however, by the Champion Lancer, whose woeful single-engine performance was, like Sir John Falstaff, a cause of wit in many men.

Like many other early aviation enthusiasts, Frederick George Miles began in the 1920s as an amateur builder. Miles then started manufacturing small airplanes and eventually turned out a series of products that recalls, in its variety and inventiveness, the career of another homebuilder-turned-professional, Burt Rutan. Like Rutan, who started the Rutan Aircraft Factory with his then-wife Carolyn, Miles found a business partner in his remarkable wife Maxine, nicknamed Blossom, who, in addition to being his beloved, was a pilot, aeronautical engineer, stress analyst, and businesswoman.

In some respects, the paths of Miles and Rutan were different. Miles made airplanes for military and commercial use. Rutan, after leaving the homebuilt plans business that had launched his career, mainly produced one-off prototypes and never certificated any of his designs. (Beech ruined the Starship, he complained, in the process of certificating it. Beech engineers naturally took a different view of the matter.) But the two shared a wide-ranging versatility. Some designers, like Thorp and Dick VanGrunsven, turn out incremental variations and improvements on a basic theme.

With Miles and Rutan, you never knew what might come next. In Miles’ case the variety may have been due in part to his employing other designers, whereas Rutan designed all of his airplanes himself. Both men mastered the art of fast prototyping: Scaled Composites, the company Rutan founded, exploited foam-cored composites for that purpose; Miles’ medium was resin-bonded wood.

Miles’ greatest commercial success came during the pre-World War II years. He developed a number of training and transport airplanes and manufactured them in large numbers for the Royal Air Force. His efforts to produce a fighter were less successful. A 1940 prototype of a small wooden “emergency” fighter, proposed to stop the gap in the event that Hurricane and Spitfire production were hampered by German bombing, had a bubble canopy and a stock Merlin “power egg,” and looked just like a miniature Hawker Typhoon. Despite fixed landing gear, it rivaled the Hurricane in armament and performance, but it was never produced, mainly because the anticipated emergency did not materialize.

During the war, Miles produced a design remarkably similar in conception to Rutan’s first homebuilt. Like the VariViggen, Miles’ original Libellula—Latin for dragonfly—had a single pusher propeller, low wing, and high canard. The configuration was supposed to solve several problems associated with shipboard fighters, but the British Admiralty didn’t bite. A second version, this one with a high wing and low canard, was conceived as a bomber, with the idea that the tandem wing arrangement would provide an unusually large CG range. That airplane also ended up on the scrap heap.

The little Gemini twin, the one illustrated in Austerlitz, was a commercial success, as was a side venture the resourceful Miles got into: ballpoint pens. But the most striking Miles design from the wartime period was something completely different.

The M.52, born in 1943, is said to have been the offspring of a ridiculous error. An intercepted German communication referred to the 1,000 kph speed of one of the jets then being developed. Someone failed to perform the conversion, and the belief took root that the Germans were perfecting a 1,000 mph airplane. Inevitably, the British felt they needed to follow suit, and Miles Aircraft earned the contract. (If it isn’t true, at least it’s a good story.)

The result was a 5-foot-diameter cylinder with thin, straight wings and a then-unprecedented, and prescient, powered all-flying stabilizer. Air for its centrifugal-compressor jet engine came in through an annular intake surrounding a shock cone, à la the MiG-17 or SR-71. The pilot sat inside the shock cone. In retrospect, the design looks sound except for its lack of area ruling, and it could probably have gone supersonic, given sufficient thrust. But in 1946, with the first prototype nearly complete, the U.K.’s Air Ministry suddenly canceled the project.

The abrupt cancellation, which was never persuasively explained, fueled a persistent notion among British airplane buffs that their government had abjectly bowed to U.S. insistence on being the first to “break the sound barrier.” Indeed, the Bell X-1 rocket aircraft, which did so in 1947, was being developed at the same time as the M.52.

However, the M.52 may have been shelved simply because of the distinct possibility that its still-unproven afterburning turbojet might not be powerful enough to propel it past Mach 1 in level flight—let alone to 1,000 mph.


This column first appeared in the May 2024/Issue 948 of FLYING’s print edition.

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A Pilot Gets Caught Between Procedure and Instinct https://www.flyingmag.com/aftermath-between-procedure-and-instinct/ Fri, 22 Apr 2022 11:12:10 +0000 http://137.184.62.55/~flyingma/aftermath-between-procedure-and-instinct/ Mistakes breed in the shadowy land between the systematic and the instinctive.

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Familiarity in flying has several components. There is the foundational element of general familiarity with airplanes and how to fly them. There is familiarity with systems; this may be of a general kind (knowing how to lean the mixture or adjust a constant-speed propeller, for instance) or specific to a particular airplane or type (such as knowing to use the left main tank of an old Beech Bonanza for takeoff when both mains are full because all return fuel from the injection pump goes to the left tank).

There is familiarity with handling characteristics: whether, for example, a certain type pitches up or down with flap deflection. There is muscle memory, knowing how much effort will be required to pitch or roll, and where to reach to lower the gear or switch fuel tanks. There is knowledge of cruising performance, clean and dirty descent rates, quality of stall warning, and post-stall behavior.

Although FAA regulations set quite precise requirements for familiarity and currency—becoming more rigorous for more complex and higher-performance airplanes—it is really hard to tell how much familiarity is enough and, for that matter, whether there is such a thing as too much familiarity. A pilot may know an airplane very well but usually fly a different type. Habits acquired from the more recently flown, or more familiar, airplane might be unconsciously applied to the other. The key word is “unconscious.” Familiarity is the thing that allows you to act without thinking. “Without thinking” is commonly a reproach, but instinctive, unconscious flying is also the hallmark of a natural and skilled pilot. There is a middle ground to be found between too much thought and too little.

How to make the first flight in a homebuilt airplane is a subject of ongoing debate, with one school arguing for short runway hops, reasoning that a few feet is not very far to fall, and another for immediate up-and-away flight, in order to get far from the rocks and hard places as quickly as possible. The impatient purchaser of a Lancair 235 tried to have it both ways.

What Happened

The pilot, 81 years old, had not flown in six months. He had about 450 hours total time. He had no experience whatsoever in the Lancair, which was turned over to him by a broker who asked him not to fly it until he had found someone with experience in the type to fly with him. The pilot promised he would not; however, he wanted to taxi-test the airplane. On his second taxi run down the runway, as the surprised broker looked on, the airplane took off and flew away.

Most likely, the pilot did not intend to break his promise to the broker, who was his friend. The airplane probably became airborne unexpectedly, and he thought it best to get familiar with it before attempting a landing.

He was gone for an hour. When he finally returned, the pilot made two landing approaches, each time going around. A witness observed that the pilot was having trouble with pitch control: “Nose up, nose down…nose up, nose down.” On the third approach, he landed long, bounced twice, climbed to 100 or 150 feet, stalled, and spun.

The National Transportation Safety Board identified the pilot’s lack of familiarity with the airplane as a contributing factor, the cause of the fatal accident being simple failure to maintain flying speed. It’s possible, however, that the pilot was not only unfamiliar with the Lancair 235 in particular but also with airplanes in general that are flown with fingertips rather than a fist. An extremely sensitive airplane is difficult for an inexperienced pilot to cope with because anxiety makes you more ham-handed and likely to overcontrol.

Some airplanes have design quirks that set them apart from others. One is the Piper Comanche, whose manual pitch trim—like that of the Ford Trimotor—consists of a crank handle in the ceiling. Early Comanches did not have electric trim, the operation of which is intuitive: forward button means nose down/go faster. Vertical trim wheels are similarly natural. The overhead crank, however, has built-in unfamiliarity.

The 3,000-hour pilot of a Comanche 250 was observed adjusting the overhead trim control as he taxied out to depart. During the takeoff roll, the propeller struck the runway surface. After breaking ground, the airplane pitched up, stalled and crashed vertically, killing all three aboard.

In principle, it should be impossible to strike a prop even with a flat nosewheel tire and a fully compressed nose strut. However, the nose-strut drag links and torque link were fractured “as if the nose gear had been forced rearward while extended.” Whether this damage arose from the crash or preceded it could not be determined; what was determined, though, was that the pitch trim was set in the full nose-down position, which would have the effect of lifting the tail as the airplane gained speed.

Another Comanche crashed somewhat similarly, although the fragmentation of the wreckage was such that the trim setting could not be determined. It was the 700-hour pilot’s second solo flight in the airplane, which he had bought two weeks earlier. He had taken the precaution of getting 15 hours of dual in it in the meantime. A witness reported the pilot appeared to intend to perform a short-field takeoff: He ran up to full power before releasing the brakes. The airplane seemed to rotate prematurely, and the witness, who was an experienced pilot, judged that it looked slow. Rather than level out to gain speed, however, it kept climbing “steeper and steeper” until it stalled and spiraled to the ground.

Although this was an early Comanche, manufactured in 1959, it was equipped with electric trim. The overhead trim is faster-acting, however. The inexorable increase in pitch angle is suggestive of an airplane that was either mistrimmed in the first place or whose pilot is inadvertently applying trim in the wrong direction while trying to get the nose down.

Fuel systems, especially ones in low-wing airplanes, which do not have a “both” position, can be a source of trouble. There are many instances of pilots using an empty tank for takeoff when there was fuel in another. Opportunities for confusion multiply as tanks become more numerous.

A 1,300-hour commercial pilot, flying a single equipped with aftermarket tip tanks, crashed while trying to return to land immediately after taking off. The pilot, who had only a few hours in the airplane, had taken off with the fuel selector on a tip tank, although use of the tip tanks was limited to whatever is meant by “level flight.” The NTSB’s report on the fatal accident does not provide information about the pilot’s previous experience, but the fact that he took off with a tip tank selected suggests he probably landed on his preceding flight with that same tank selected—also forbidden—and his previous experience may have been in airplanes, such as high-wing Cessnas, that do not require so much attention to tank selection.

Mistakes breed in the shadowy land between the systematic and the instinctive. Only by forcing our actions up into the realm of conscious procedure—for instance, by methodical use of checklists and each crewmember’s critical attention to the actions of the other—can we reduce our reliance on instinct and the unconscious errors that come with it.

This story originally published in the December 2019 issue of Flying Magazine

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Looking at the Physics of STOL Drag https://www.flyingmag.com/voices-of-flying/looking-at-the-physics-of-stol-drag/ Wed, 22 May 2024 13:06:02 +0000 /?p=207956 Racing circuit's airplanes requires
starting and stopping twice while flying
less than a mile.

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At a point in my meandering journalistic career, I found myself behind the wheel of a Porsche 911 Turbo on a Southern California racetrack. One of the turns was a 90-degree elbow of essentially zero radius that came at the end of a long straightaway on which the sports car would reach 120 mph or so. The problem—which resembled the game of chicken in the 1955 film Rebel Without a Cause and which I was shamefully slow to master—was to use maximum braking just in time to arrive at nearly zero speed right at the corner, but not a moment sooner.

Slowing down matters as much as accelerating in most auto racing, and the same is true of STOL Drag racing. Unlike traditional Reno-style pylon racing, which involves no slowing down whatsoever, STOL Drag requires starting and stopping twice while flying less than a mile.

I have never been to a STOL Drag race, and so I will probably be pummeled for whatever I say, but here goes anyway.

Two pylons and corresponding start/stop lines are set 2,000 feet apart. A third pylon is placed at the 1,000-foot mark, just for reference. The idea is to take off from the first line, fly to the far line, land, come to a full stop, turn around, and repeat the process without touching the ground between the lines. Two airplanes compete side by side, and the winner is the one that first comes to a full stop at the end of the race. Best times are just over 50 seconds, so, for a pleasurable activity, it’s brief.

In principle anyone can participate, but the really serious competitors use highly modified airplanes that can accelerate like mad and stop very short after touching down. However, competitors are paired off according to aircraft performance, so it wouldn’t be unusual to see a Skylane compete against a Beech Bonanza.

Since it’s a time trial, the race rewards acceleration, speed on the airborne segment, and deceleration after each landing. But the equation is complicated by the need to begin to slow down long before reaching the far pylon. Pilots accomplish this by chopping power, kicking in full rudder, and slipping toward the line. But even this phase isn’t as simple as it sounds. Airplanes decelerate quicker with wheel braking than aerodynamic braking, so while it may seem as if it’s best to touch down at minimum speed to reduce the rollout distance, it may actually be better to get the wheels on the ground as quickly as possible, even a few knots above the stall speed.

Initial acceleration is a function of the airplane’s mass and the engine-propeller combination’s thrust. Big thrust requires lots of power and a big prop. Two of the dominant competitors in the sport, Toby Ashley and Steve Henry, fly a Carbon Cub and Just Aircraft Highlander, respectively.

(Henry’s Nampa, Idaho, company, Wild West Aircraft, sells the Highlander as a light sport kit.) Neither racing airplane has much in common with its ordinary Lycoming- or Rotax-powered brethren. Both use liquid-cooled, geared, turbocharged, intercooled engines with very big props. They say the engines put out around 400 hp. The airplanes are stripped down, competing at weights less than 1,000 pounds. Since they are generating more than 2,000 pounds of static thrust, and therefore achieve an initial acceleration of 2Gs or more, it’s not surprising that both get airborne in a couple of seconds and a few dozen feet.

The powerful initial acceleration does not last long, however, because thrust diminishes as speed increases, and drag grows in proportion to the square of speed. At 90 knots, which an airplane accelerating at an average 1G would reach in five seconds and 400 feet, drag has increased to more than 200 pounds and thrust is cut in half. Since the drag can be subtracted from the thrust to get the net force accelerating the mass of the airplane, it follows that the forward acceleration may already be well under 1G.

The actual segment times, based on videos of Henry racing at Reno last year, are, as you would guess, asymmetrical, reflecting the fact that it is easier to speed up than slow down. From brake release to throttle down at midcourse, about 10 seconds elapse. From there to wheels on, another 10, but at that point the airplane is still moving at around its stall speed of 35 knots. The rollout takes four seconds and another four to get turned around. The times going back are similar for a total of 52 seconds.

If the average acceleration up to the middle of the course were two-thirds of a G, the maximum speed attained would be about 125 knots. If the touchdown speed at the far end were 35 knots, the average deceleration in the slip would be a bit under under one-half G—more at the start and less at the end. By the time the wheels touch the ground, the rate of deceleration is pretty low. Wheel braking brings it back up to the half-G level.

The Carbon Cub and Highlander regularly finish within a fraction of a second of each other, and successive heats also differ by small amounts. That consistency is a testament to the pilots’ skills, since, as you find when you watch any of Henry’s cockpit videos, quite a lot goes on during the brief race. Everything hinges on the deceleration timing, staying as low as possible, and amount of wheel braking that can be applied without nosing over.

Henry claims to use his airplane as a daily driver—probably at about 20 percent of power. But I suppose that if STOL Drag racing continues to be popular, it may eventually engender purpose-built airplanes. Very likely the slip-to-slow-down approach would be supplemented or replaced by large air brakes that would add several square feet to the airplane’s equivalent flat plate area. Maybe a slight edge in acceleration could be gained by cleaning up the front end, replacing the big intercooler radiator with a small tank of ice water, and getting engine cooling air to the main radiator with a scoop and duct. But aerodynamic refinement may be pointless, since so little time is spent at high speed.

High wings and a tailwheel are taken for granted on STOL airplanes for a lot of practical reasons. But I wonder whether a low wing with some extra span—taking better advantage of ground effect—and tricycle gear with brakes on all three wheels might bring some advantages. Add lots of horsepower and an airfoil with a maximum lift coefficient of two, and then…off to the races!


This column first appeared in the April 2024/Issue 947 of FLYING’s print edition.

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Three-Mile Limit: Novice Pilots Succumb to the Perils of Total Darkness https://www.flyingmag.com/three-mile-limit-novice-pilots-succumb-to-the-perils-of-total-darkness/ Tue, 07 May 2024 13:06:08 +0000 https://www.flyingmag.com/?p=202267 Departing Key West unexpectedly in February 2012 cost two Polish nationals their lives in a Cessna 172.

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In February 2012, two pilots returning from a vacation trip to Bimini in the Bahamas found themselves obliged to divert to Key West because of a presidential temporary flight restriction (TFR) at Miami. The 172 they had rented was not due back at Miami Executive Airport (KTMB) until the next day, but the TFR was scheduled to end early that evening, and they decided they would clear customs and get dinner in Key West and make the 92 nm trip back to Miami afterward.

Both pilots were in their early 30s and were Polish nationals. Both held FAA private pilot certificates based on their Polish certificates. They were relative novices, with 210 hours total time between them, only 130 as pilot in command (PIC). Neither was instrument rated, and only one was legally qualified for night VFR flying. (Their FAA certificates required them to comply with the limitations imposed by their Polish ones.)

After having dinner in town, they returned to Key West International Airport (KEYW) around 8 o’clock. It was dark, the sun having set an hour and a half earlier. The moon, new two days before, was now a smiling sliver on the western horizon. By the time they boarded the airplane, it too had set.

Presumably because he was the one who had done the rental checkout, the less experienced pilot of the two, with 30 hours of PIC time, took the left seat, and his companion took the right. It was the pilot in the right seat, however, who held the night qualification.

They began their takeoff roll at 8:33 p.m. When they were airborne, the tower instructed them to make a left turn northbound, remain clear of Navy Class D airspace, and contact Navy tower for transition. “Navy” meant Naval Air Station Boca Chica (KNQX), whose airspace abuts that of KEYW.

The tower frequency for KNQX is 118.75, but the pilot read back only 118.7, followed by a pause and then the last three digits of the Cessna’s call sign, “five eight niner.” The “five” was ambiguous, but it is possible that the pilot handling the radios missed the final “five” in the Navy tower frequency. In any case, that acknowledgement was the last communication heard from the Cessna.

In the early afternoon of the following day, some pleasure boaters noticed an object floating in the water. They thought it might be a manatee and approached it cautiously, only to find that it was a human body. The water was shallow, just 7 feet deep, and perfectly clear. Parts of an airplane could be seen resting on the bottom. The site was less than 3 miles from the Key West runway. 

Accident investigators found that an airport surveillance camera had recorded the airplane’s lights as it departed. Its flight path was erratic, descending, leveling off, descending again, leveling off, and then disappearing from view.

A witness, who had been fishing from a nearby bridge and read about the accident in the newspaper the following day, reported having seen what he thought at the time was a firework but now realized might have been a red light on the airplane descending rapidly toward the water.

The National Transportation Safety Board (NTSB) attributed the accident to “the non-night-qualified pilot’s improper decision to depart in dark night meteorological conditions, which resulted in his subsequent spatial disorientation…”

A direct line from Key West to Miami bears about 055 degrees, and about half the trip is over open water. On a dark night, the danger of disorientation is great. The brightly lighted line of the Keys recedes on the right, while the dark Everglades lie ahead. Miami is a pale glow beyond the northeastern horizon. The two pilots having just returned from the Bahamas, flying over open ocean in a single-engine airplane evidently held no terrors. (They had, nevertheless, taken the precaution of wearing life jackets.)

Most likely, however, they had no idea that the main danger of a night flight over open water was not that they might have to ditch after an engine failure, it was that they would lose the horizon and fly into the water before they even realized that something was wrong.

The fact that one of them was legally qualified for night flying meant only that he had logged a certain number of hours and takeoffs and landings at night with an instructor, not that he had any experience flying at night in this particular kind of environment. In any case, the pilot with the night qualification was sitting in the right seat, and to the extent that he might have made better use of the attitude indicator, he was not in a position to do so.

This is not an unusual kind of accident. I have written in this column about many similar ones, including two Barons and a Citation that flew under control into Lake Erie immediately after taking off from Cleveland Burke Lakefront Airport (KBKL); a Lancair 550 and a Cessna 210 that crashed immediately after taking off on moonless nights in desert terrain; and a Piper Cherokee, on another island of the Florida Keys, that went into the water a couple of miles from the runway from which it had just taken off.

Note the recurrence of the phrase “taking off.” The airplanes that took off over a pitch-dark lake or desert invariably climbed only a few hundred feet before they began to bank, then the bank grew progressively steeper, and the climb became a dive. The pilots were unaware that anything was wrong. Once the lights disappear, the rest lasts a matter of seconds, or at most 2 or 3 miles.

The two Polish pilots did fine at first, while they were over the lights of Key West. It was only when they left the lights behind that the insidious effects of darkness beset them. Neither pilot had instrument flying experience beyond the hood work required for the private certificate, which bears more resemblance to an arcade game than the real sensations, physical and emotional, of piloting an airplane in total darkness.

In pilots’ careers certain dangers are bound to arise for which it is very difficult for an instructor to prepare them. Many of those dangers are associated with loss of a visible horizon, whether because of fog, clouds, or darkness.

Warnings to believe the instruments, not bodily sensations, may be memorized, emphasized, and faithfully repeated, but they are never so persuasive as the sensations themselves. One must work hard to develop the discipline to level the tilting wings of the attitude indicator despite an overwhelming impression that the instrument has failed and the airplane is still in level flight.

Unfortunately, not every airport has an ocean or large lake handy with which to impress upon the student pilot the perils of total darkness—and Warsaw is far from the Baltic Sea.


Note: This article is based on the National Transportation Safety Board’s report of the accident and is intended to bring the issues raised to our readers’ attention. It is not intended to judge or reach any definitive conclusions about the ability or capacity of any person, living or dead, or any aircraft or accessory.


This column first appeared in the March 2024/Issue 946 of FLYING’s print edition.

The post Three-Mile Limit: Novice Pilots Succumb to the Perils of Total Darkness appeared first on FLYING Magazine.

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