Diagnose this: rough engine on approach

Airplane: Piper Warrior II (O-320 engine)
Airport: CYGK (north shore of Lake Ontario
Time: afternoon
Weather: CAVU; 15°c OAT; prevailing westerly winds, but airport in local light lake breeze from the south

About five miles back from landing today, I noticed the engine running rough whenever I reduced power — it was fine above 2,200 RPM, but started vibrating at any lower setting, enough that the plane (carbureted) shook noticeably. I accepted the vibration, landed, and taxied to the ramp, with the plane still shaking. I switched mags while taxiing and tried different mixture settings, with no difference. When I tried to shut down with the mixture lever, the engine kept running (even at full lean), and I had to stop it with the mags.

Your diagnosis? (I’ll post the answer in a day or two).

Posted in General | 9 Comments

Personal IFR minima

One big source of stress around flying is indecision: if all things (people, weather, and equipment) are perfect, it’s an easy choice to fly; if something’s clearly awful (you have the flu, there’s freezing rain, the plane has a major mechanical problem), it’s an easy choice not to fly. If it’s somewhere in the middle, the stress starts — is it really worth letting yourself or other people down because of a forecast for a chance of X or Y that probably won’t happen?

To reduce that stress, I’ve long wanted to put together sets of personal weather minima. Here’s my first draft, for IFR flight in a Piper Cherokee.

Personal day IFR minima

  • Destination forecast meets standard alternate minima for ceiling or visibility, or a nearby larger airport does.
  • Freezing level forecast at least 2,000 feet above MEA.
  • No worse than scattered CB forecast along route.
  • No severe turbulence forecast along route (at my altitudes).
  • Always within 60 minutes of a usable diversion airport.

Personal night IFR minima

  • All day IFR minima.
  • Freezing level forecast at least 4,000 feet above MOCA.
  • No worse than isolated CB, TCU, or ACC forecast along route.
  • Always within 45 minutes of a usable diversion airport.
  • No CB or TCU forecast at destination.

I don’t want the minima to be so lengthy that I ignore them, so strict that I start making exceptions, or so lax that they don’t really help me make the fly/no-fly decision. I’m very interested in feedback from other pilots — please let me know what you think, good or bad.

Posted in General | 7 Comments

Pilot advice on OurAirports?

I’m still hoping to do a responsive redesign on OurAirports if I can wedge some free time into my schedule. I’ve also been thinking about how to make the site less CRUDy (browsing lists of things) and more generally useful (helping people do stuff).


Yesterday, I was playing around with a new METAR parsing class, and I realized how easy it would be to start offering advice to people based on the weather and other information. The advice would be fairly generic, and couldn’t (in most cases) take into account local special conditions, but there’s still a lot you can do with a small amount of information:

  1. You can mark the conditions generically as VFR, MVFR, IFR, or LIFR.
  2. You can warn pilots to keep an eye open for icing (freezing precip or low ceiling in low temps), wind shear (big difference between winds aloft and surface winds), strong winds, unforecast fog (small temp/dewpoint spread), unforecast convective activity (high dewpoint), etc.
  3. You can warn passengers to check for weather-related delays based on some of the above, combined with how busy the airport is.
  4. You can tell passengers whether there might be a bumpy ride on approach or climb-out
  5. You can check the available runways to see if there will be strong crosswinds.
  6. In a fancy implementation, you could look at the surrounding DEM and suggest whether the ceiling might be low enough to hide surrounding hills (etc.), even if conditions are otherwise VFR.

Is this a good idea?

Does this sound interesting to you as a private pilot, commercial pilot, or airline passenger? It wouldn’t be meant to replace real pilot weather briefings, but rather to give you a single-glance overview on your computer or smartphone screen before you start the real prep. For passengers, it would give them an idea of when to expect problems at airports, before the delays start showing up on the big screens.


I was even thinking of creating two personalities, an Airport Old-Timer in a rocking chair on the FBO porch (pilot advice) and the Frequently Flyer in a business suit (passenger advice), but that feels a bit too much like resurrecting Clippy.

How else might I take OurAirports past a data repository to something genuinely useful to pilots and airline passengers? Advice is welcome, even from talking paperclips.

Posted in General | 9 Comments

Link: Private pilots pushed out of hangars at Toronto island airport


Porter contends that the Q400 turboprop planes it flies qualify the airline’s activities as general aviation.

I love Porter as an airline, but that statement (if accurately reported by Macleans) is BS of the worst kind. Porter is trying to claim that it’s a general-aviation operation because the tripartite agreement governing CYTZ calls for the preservation of GA at the airport, and Porter has been working to squeeze out resident GA (though they’re great with transients).

Porter knows perfectly well, though, that it doesn’t operate under the sections of the CARs (Canada) or the FARs (US) that govern GA, but is regulated as an airline, just like Air Canada or Westjet.  Let’s hope the Toronto Port Authority isn’t as stupid as Porter assumes.

Posted in General | 4 Comments

Less noise in the cockpit

I took this morning off and went for my first flight of 2013. Something was wrong with my Bose headset or its batteries, so I had to do without noise cancellation, but it was a wonderfully-quiet flight in a different way.

Toys or no toys?

Normally, I mount a Garmin 696 portable GPS on my yoke, with a full-colour moving map, terrain and obstacle alerts, live satellite weather, nearby traffic alerts fed from a Zaon XRX, and even XM satellite radio. For a long cross-country flight, that stuff is very helpful, letting me see and plan for what’s happening 200 miles ahead and listen to the BBC to kill the long hours. It does, however, require a yoke mount and a complex series of power, antenna, and audio wires threaded carefully out of the way around the cockpit.

I had planned to reinstall all of that before flying (I removed it for the plane’s annual last month), but then I looked at the beautiful, simple panel with its analog “steam” gauges, looked up at the blue sky, and asked myself “why bother?”

I took off and followed frozen rivers around Eastern Ontario at 2,000 ft. I started without the map, but pulled it out for fun to identify towns and villages whose names I didn’t know (for the bigger ones, I just read the water towers).

After 2 1/2 months without flying, my pre-flight skills were a bit rusty (I forgot to remove the pitot cover, and had to shut down and restart on the taxiway), but my stick-and-rudder skills were surprisingly good — the altimeter seemed to stay pegged on 2,000 ft even when I was distracted enjoying the scenery, wind-correction angles set themselves, etc.

Too much information?

I don’t think I suddenly became a better pilot, especially after almost a full season away from the cockpit. My only conclusion is that I was less distracted. I’ve never been one of those fools who flies head-down playing with the toys instead of looking out the window, but still, every piece of information available to me is something my brain has to process, whether I’m consciously focussing on it or not. Without the GPS hurling groundspeed and heading at me, without the traffic system telling me there was another plane 2 miles away, without pictures of airports and airspace scrolling across a colour screen a couple of feet from my face, I simply didn’t have as much to think about.

Modern avionics are great, and in many situations — complex airspace, IFR, etc. — they actually lower the workload. But for an easy VFR flight in familiar airspace, I think that leaving it packed away made me a better pilot.

Further reading: Eight years ago, as a fairly new pilot, I posted about something similar for the instrument scan in Analog Flying. I strongly suspect that’s the best article — and possibly the only truly useful one — that I’ve posted in this blog.

Posted in General | 3 Comments

10 years as a pilot

Ten years ago today, I passed a flight test and received my Private Pilot’s License (PPL) in a rented Cessna 172 (C-GPMR) at the Ottawa Flying Club.

I’d been worried about turbulence — I didn’t quite have my flying stomach yet, and had nearly thrown up all over the panel during the practice test with my instructor a day or two earlier — but the late-afternoon air that day was still and smooth, and while I didn’t cover myself with glory in every exercise, I did perform them all to the examiner’s satisfaction. After I landed back at Ottawa Airport and started taxiing towards the club, the examiner told me that I’d passed, and was a licensed pilot.

At the time, I knew what my immediate next steps would be: a night rating, then an instrument rating. But after that, what? I had no interest in going on to get my commercial license and instructor rating so that I could teach flying myself on the weekends, and if I just kept renting planes for short local flights, I’d probably get bored in a couple of years (like most new PPLs do). As much as I hate to admit it, the “oh my god I’m in the air!!!” thrill fades after a while, and taking off or landing is about as exciting as parallel parking a car.

As it turns out, I’ve flown a lot over the past 10 years, though I’m still just a bit short of the magic 1,000 hour mark. In December 2002, I bought a used 1979 Piper Warrior and started using it for family trips and business travel (it helped that my consulting customer base suddenly shifted from the California to the US northeast). I flew a lot. I flew in rain, snow, dodged thunderstorms, tried to avoid (and dealt with) icing, and learned how weather changes over long flights. My first big cross-country was four hours to Sault Ste Marie in 2003, before I had my instrument rating, and I got weathered in for a day in North Bay on the way back. Around the same time, I did my first flight down into New York Approach airspace, and didn’t find it frightening at all. Soon, many other trips to big and small airports followed: Montreal, Toronto Island, Halifax, Philadelphia, Gaspé, Washington DC, Boston, Winnipeg, etc. (check out this map of all the airports I’ve flown to). I joined Hope Air as a volunteer pilot, and learned what it’s like to fly on someone else’s schedule and make the kind of complicated go/no-go risk assessments that commercial pilots have to make every day.

I thought I’d upgrade to a faster plane before now, but I’m happy with my Warrior. It’s slow in cruise, and it can barely climb above 7,000 ft on a hot summer day at maximum gross weight (I actually lose altitude in downdrafts), but I’ve been through pretty-much everything with it and know that I can trust it. I know that it will meet the performance numbers in the manual for taking off from a short grass strip with unforgiving trees looming at the end, I know it will let me land safely in a 20+ kt straight crosswind, I know it will keep flying with a bit of ice on the wings and the windshield frosted over, I know it will still let me sort-of control it inside a fast-building TCU, and I know that the heater will keep me from hypothermia when the outside temperature is -38°c. I know that I can get a folded-up wheelchair in through the front door and over the seat when a Hope Air patient shows up with one unannounced (thanks to my flying buddy Mike Hopkinson for help with that one).

Perhaps more importantly, my kids got to grow up seeing Canada and the US from the air as well as from the car window. Halifax is 4 hours away rather than 2 days. The Bay of Fundy looks like a bay. The customs guy in Beverly MA remembers us every year, and likes to chat about the Red Sox with my daughter. We park beside bizjets. At Teterboro Airport near NYC, my daughters used the same lounge as Oprah (though not at the same time).

I don’t fly as much as I used to — more like 70 hours/year vs 120 early on — and if I had a faster, more complex plane, I might have to give it up, because it would cost a lot to own and fly (fuel, insurance, and maintenance costs for my Warrior are a bit less than they would be for a second family car), and I’d have to fly a lot more to stay safe in it. C-FBJO and I are a good fit.

So there we go. I wonder if I’ll still be flying in another 10 years.

Posted in General | 11 Comments

Control feedback

Co-pilot's sidestick from an Airbus A321.

Control feedback is important to pilots. Through the yoke or stick, we can feel what’s happening with the plane; for example, are we pulling or pushing too hard on the stick? Are the controls mushy, indicating that we’re close to a stall? Are they fluttering, possibly because of misbalanced control surfaces or icing? Are they bouncing round in turbulence? This stuff is so important that sophisticated, fly-by-wire airliners, which have no direct connection from the yoke or stick to the control surfaces, actually simulate some of it.

I do most of my flying as the only pilot in my small plane, so I never considered how important control feedback is for feeling what the other pilot is doing. It turns out that lack of that kind of feedback is one of the major links in the accident chain that brought down Air France 447 in 2009, as described in detail in annotated CVR transcript in this Popular Mechanics article.

Throughout the incident, one of the pilots was panicking and pulling all the way back on his stick. It wasn’t the thunderstorms that brought the plane down, but a mush from 37,500 ft all the way down to sea level. At any point before the last few thousand feed, the jet would have recovered if the pilot had simply released the stick. The psychology of stress and panic are complicated, and I’m not writing this to condemn the poor pilot who did that; however, the point of requiring two people in the cockpit is that if one is incapacitated (whether by panic or illness), the other can take over.

In this case, however, the other pilot wasn’t aware of the problem, because a crucial piece was missing: Airbus designed the A330 with asynchronous control sticks — that means that the pilot in the left seat had no easy way of knowing that the pilot in the right seat was holding the stick all the way back, because the other stick remained in a neutral position. At one point, when he did push his stick forward, the Airbus simply averaged the two inputs — to me, that makes about as much sense to as averaging two wheels on a ship, when one wheelman turns 15 degrees to the left of an iceberg, and the other turns 15 degrees to the right.

There were many other causes in the accident chain, of course (for example, the pitot tubes initially iced over, so the flight computer didn’t have good airspeed readings, and it shut off the system meant to prevent pilots from stalling the plane), but the glaring one seems to be Airbus removing, by design, a cockpit-resource-management tool that almost every other type of aircraft has: the ability to see and feel the other pilot’s control inputs.

I’d be interested to hear from anyone who knows Airbus’s reasoning behind designing asynchronous control sticks and (in some control regimes) averaging the inputs.

(Photo credit: Flying China Man blog)

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