Category: Flying

A two-seat light sport plane crashes near the runway while a 13-knot wind is blowing. The 90-year-old pilot is killed. Who is to blame? Jasmine, the right-seat Labradoodle, according to the NTSB report. The probable cause:

The pilot’s decision to fly with his large dog in the two-seat, light sport airplane, and the dog’s likely contact with the flight controls during landing, which resulted in the pilot’s loss of airplane control and a subsequent aerodynamic stall when the airplane exceeded its critical angle of attack.

Without a cockpit video recorder, how exactly do we know this?

A witness, who was piloting another airplane in the traffic pattern, reported that, while he was on the downwind leg, he saw the accident airplane on final approach to the runway.

Based on available ground track and engine data, the airplane crossed the runway 27 threshold at a calculated airspeed of 48 knots. About 3 seconds later, the airplane turned right away from the runway heading, and the engine speed increased to takeoff power.

Given the ground track and engine data, it is likely that the dog contacted the aileron and/or stabilator controls during landing, which resulted in the pilot’s loss of airplane control and a subsequent aerodynamic stall at a low altitude when the airplane exceeded its critical angle of attack.

Does it make sense to blame Jasmine? She was manipulating the flight controls? Maybe. But wouldn’t a Labradoodle be more likely to push nose-down rather than grab the yoke with her teeth and pull nose-up? And the Labradoodle was also responsible for initiating a go-around by adding full throttle?

(Separately, as is typical with car accidents that kill humans, the supposedly inferior canine more or less walked away:

After the accident, the witness saw the pilot’s dog, who had been onboard the airplane, running out of the cornfield where the airplane had crashed. First responders were able to catch the dog, who was treated for minor injuries by a local veterinarian.

)

Related:

• 2015 crash of same type of aircraft during go-around (no non-humans on board)
• “Trim Use on Go-Around” (Flying): “The possibility for a stall increases during a go-around when a great deal of nose-up elevator trim is dialed in and full power is suddenly applied. With the elevator trim set for approach attitude, the nose-up pitching moment can be very pronounced, leading to trouble in a hurry if you aren’t on top of things.”
• tutorial on the risks and how to train to avoid them (“Landing Accident Is Safer Than A Go Around Accident”)
• Flying Magazine article citing go-around accidents (“The stats also showed that one in 10 of the go-around efforts resulted in a potentially hazardous outcome”)
• French NSTB-equivalent looks at airliner accidents during go-arounds, including stalls (by a crew of two professional pilots in every case; only Captain Sully was able to fly an Airbus solo!)
• TBM stalled and crashed during a go-around

I was asked to fill out a form showing the aircraft that I have flown and it turned out to be a longer list than expected…

1. 8KAB (Decathlon)
2. AA5 (Grumman Tiger)
3. AC95 (Twin Commander 1000 turboprop)
4. B200 (King Air 200 turboprop)
5. B206
6. B505 (new Jet Ranger)
7. BE36
8. BE55
9. BE58
10. BE103 (Beriev twin-engine seaplane!)
11. C172
12. C182
13. C210 (in southern Africa)
14. C310 (crazy noisy!)
15. C510 (Cessna Mustang jet)
16. CJ3
17. CL65 (Canadair Regional Jet)
18. COL4 (Columbia 400/Cessna 400)
19. DA20 (Diamond Katana)
20. DA40 (Diamond Star)
21. EMB-500 (Phenom 100 jet)
22. Evolution (experimental turboprop)
23. Gamebird GB1
24. HK36 (motor glider)
25. M20T (turbocharged Mooney)
26. PA12 (Piper Super Cruiser… on floats!)
27. PA28
28. PA32
29. PA34
30. PA38 (with a very slender student!)
31. PA44
32. PA46 (Malibu; the dream family airplane as long as one can get a letter from God promising that the engine won’t quit)
33. PC12
34. R22
35. R44
36. R66
37. SGS 2-32 (glider)
38. SGS 2-33 (glider)
39. SR20
40. SR22
41. TBM850

Adding to this blog so that the information doesn’t get lost. I was thinking that it would be good to put the favorites in bold, but I realized that at least half of the above aircraft would need to be marked. Most of them have at least some great characteristics.

The list would be a bit longer if I included variants, e.g., the turboprop versions of the PA46, the retractable version of the PA28, or the turbocharged version of the SR22.

Despite FAA English proficiency requirements for certificate holders, I am having some trouble understanding this new copilot. I think that he is complaining about the lack of A/C in the Cirrus:

Thirty years ago, 85 percent of students and instructors could conduct training in a two-seat airplane. Today, 85 percent of students and instructors need to use a four-seat airframe. It would be inconceivable for four typical GA-interested American adults to take off within safe weight & balance limits for the typical 1950s or 1960s-designed airframe.

Cirrus responded to the changed circumstances by making the SR22, a four-seater with 1,000 lbs. more gross weight and twice the horsepower compared to a 1960s four-seater.

Piper has done something interesting. They’ve taken a seat out of their four-seater (1960 design), put in an experimental glass panel, and delivered a new IFR-capable three-seat airplane, including the fantastic Garmin GFC 500 autopilot, for $285,000 (down from more than $370,000; compare to a Cirrus SR20 at $455,000 before options). And it probably will be able to take off with three adult Americans circa 2020!

One issue: the airplane will be called the “Pilot 100”. Did the marketing staff at Piper recently come over from Dorco USA?

See this article from Plane&Pilot.

One unusual twist is using a 180-horsepower engine from Continental, now under Chinese ownership. Industry experts say that Lycoming makes a more reliable engine, especially the IO-360 Lycoming. Also that Lycoming support is far superior. Cirrus recently dropped Continental as a supplier for its lower-powered model, the SR20.

(Out of a handful of SR22s in our T hangars, the premature failure rate on the bigger Continental engines has been high. One failed catastrophically at 300 hours. Another failed at about 900 hours (supposed to last 2,200) and one month after its three-year warranty expired. Continental refused to do anything for the customer other than sell him a new engine at the standard price.)

“Doomed Boeing Jets Lacked 2 Safety Features That Company Sold Only as Extras” (nytimes):

Boeing’s optional safety features, in part, could have helped the pilots detect any erroneous readings. One of the optional upgrades, the angle of attack indicator, displays the readings of the two [angle of attack] sensors. The other, called a disagree light, is activated if those sensors are at odds with one another.

Boeing declined to disclose the full menu of safety features it offers as options on the 737 Max, or how much they cost.

When it was rolled out, MCAS took readings from only one sensor on any given flight, leaving the system vulnerable to a single point of failure. One theory in the Lion Air crash is that MCAS was receiving faulty data from one of the sensors, prompting an unrecoverable nose dive.

[Watch the Aerodynamics lecture from our MIT FAA Ground School to learn more about angle of attack.]

As I noted in a previous posting, the Pilatus PC-12, a much cheaper and simpler airplane (1 engine and 9 passenger seats), doesn’t do any nose-down pushing unless two separate angle-of-attack sensors, and their respective computers, agree. Boeing’s ideas of

• a system that works silently (so pilots don’t realize it is operating)
• a system that works if just one sensor suggests a high angle of attack
• a system that has the authority to drive the airplane into a full nose-down trim situation
• a Band-Aid on the above in the form of a “disagree” warning light

are all terrible ones, as far as I can tell, and unconventional within the industry.

Does that mean we need much more stringent oversight by regulators? (as noted in this other previous posting, the “regulators” in the case of the above system were mostly Boeing employees) Maybe.

The prices of these optional items that would have made Boeing’s unsafe design a little less unsafe were too shocking for Boeing to admit or the NY Times to publish. But reasonably high-quality systems for homebuilt 2-seat and 4-seat airplanes are less than $2,000, including both the sensor and indicator. Examples:

• Garmin, probably as good as anything in the airliner world (and also supposedly available for small certified planes)
• A $389 LIFT system
• AOA Sport, Angle of Attack Instrument
• iFlyAOA (can be added to small certified airplanes as well)
• LevilBOM (my favorite! can be mounted under the wing of a certified airplane; gets its power from the moving air)

So it is tough to know whether regulation should have been relaxed so that Boeing’s costs of putting reasonably modern avionics into the airplane were reduced or toughened so that the crazy bad ideas were squashed. (Or, as my previous posting suggests, shifted so that an independent private engineering service would do the steps that Boeing’s employees were doing while nominally wearing FAA hats.)

Participants at a local gathering of pilots were required to tell a joke. Here’s what I said…

I don’t want to tell a joke because so many people in this world are suffering with serious problems, like [FAA non-essential air traffic control employee, previous speaker] who talked about his personal struggles in Arizona and Europe during the paid 35-day shutdown.

I’m teaching computer programming this month at Harvard Medical School. One of the residents talked about a recent case that he observed.

A pilot came into the hospital and said “When I’m on final at 6B6 I can’t get the song ‘The green green grass of home’ out of my head. If I see a Grumman Cheetah on the tie-downs then it’s ‘What’s new, pussy cat?’. It’s distracting me from my approaches and preflights.

The attending physician said, “I’m pretty sure that you’re in the early stages of Tom Jones syndrome. Unfortunately, 72.3 percent of the time the disease is progressive and incurable.”

“72.3 percent?!? How have you seen enough cases to give a precise number like that? I’ve never heard of Tom Jones syndrome so I assume it is quite rare.”

The doctor thought for a moment. “Well, it’s not unusual.”

Unfortunately, we now know that a two-pilot crew cannot safely handle the silent gradual pusher system of the Boeing 737 MAX.

“Pilot Who Hitched a Ride Saved Lion Air 737 Day Before Deadly Crash” (Bloomberg) says that a three-pilot crew was able to handle the design deficiencies in Boeing’s silent gradual pusher system. (The third pilot was in one of the comfy jump seats; I enjoyed a ride once in a B757 jump seat and it is remarkably luxurious.)

One of the ideas that I’ve been in love with for years is a robot copilot up in the dome light that can see everything the pilots see and, without anyone having to certify modifications to the legacy systems, help out with suggestions in the intercom. In the case of the 737 MAX, for example, the dome light copilot could notice when the runaway-trim-by-design system is operating and suggest “hit the trim interrupt switches!”

(Alternatively, of course, the Boeings could be returned to service with the requirement that they be flown by three pilots in the cockpit at all times, like a World War II bomber or Boeing 727. (In the not-so-good old days, a heavy airplane would have two pilots to manage the flight controls, a flight engineer (i.e., a third pilot) to manage the systems, and a navigator to watch the position over relative to the ground.))

Related:

• https://philip.greenspun.com/blog/2017/11/21/air-force-f-16-runway-overrun-good-argument-for-the-dome-light-copilot/
• https://philip.greenspun.com/blog/2017/08/02/time-for-a-robot-assistant-up-in-the-dome-light-of-the-cockpit/