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)

Posted in General | Tagged , | 3 Comments

The complicated finances of flying

The original news story was simple: pampered general uses private government jet for personal trip(s) at total cost of more than $1M to taxpayers over three years. The Prime Minister smelled a scandal and tried to nip it in the bud by suggesting public figures repay personal travel costs.

Fixed vs incremental costs

Unusually for a public figure, however, the general in question actually stood up for himself and decided to treat us like adults and explain how things work. The situation is remarkably similar to the finances of owning a small plane (if you knock a couple of zeros off the end of the dollar values), so it’s worth summarizing here:

  • The $10,000/hour quoted cost is the total cost of ownership, not the incremental cost. The bulk of that is the fixed costs (purchase, maintenance, etc.) divided by flying time. Most of those costs are incurred regardless of whether the government’s two Challenger jets take extra trips. The incremental cost of flying one of the jets (fuel, maintenance based on flight hours, etc.) is $2,360 for each extra hour it flies.

  • The government doesn’t use the jets often enough for the crews to maintain legally-required recency, so they have to do a lot of empty training flights to make up enough hours. Last year, the jets flew 170 hours empty between them to help the crews meet requirements.

So when the press says the general spent $1.5M over three years flying for personal reasons (presumably ~150 hours), the first thing to realize is that that really represents $354,000 in extra incremental costs, or just over $100,000/year — still a lot, but not nearly so shocking (in the late 1990s, my customers spent over $50,000/year more than one year flying me around on the airlines for my consulting work).

Crews have to fly

The second thing to realize is that the pilots have to fly anyway. So imagine an exchange like this:

Jane Pilot: Good morning, sir. My first officer and I need another 8 hours this month to stay current. Instead of our flying in circles around Ottawa practicing approaches, would you like to tag along and go somewhere?

General: Well, captain, my friend gave me tickets for the Calgary Stampede.

Jane Pilot: Perfect — that will be just about right. See you tomorrow morning at 0800, sir.

This conversation will make perfect sense to an aircraft owner, but might be too complicated to explain in the public — we’ll see. I’ve had similar conversations with friends when I’ve needed to make up required hours (a pilot who doesn’t fly often enough isn’t safe, and sometimes isn’t legal). Of course, my incremental operating costs are a lot lower (maybe $70/hour for fuel, oil, and engine depreciation), but who’s counting?

Not the same as a corporate jet

If these were privately-owned corporate jets, of course, they could be leased out when they’re not needed, and the owner would make money and give the crew their hours. These jets, however, are full of sensitive equipment, so that the Prime Minister (for example) can monitor or order military attacks from the air. We probably don’t want a rich developer renting one to fly his gulf buddies to Florida.

It’s also worth mentioning that in at least one case, the jet was offered to the general because he missed the first part of a family on a trip to be present for the return of slain Canadians from Afghanistan. That’s a hard one to object to.

Posted in General | 4 Comments

What happens after you get your private pilot license?

Yesterday was the 9th anniversary of the day I passed my flight test and got my private pilot’s license (PPL). It was also, coincidentally, the longest straight-line distance I’ve flown in a day, 930 nautical miles (1,722 km) from Winnipeg to Ottawa. When a fellow aviator made a comment about Ground School on Google+, it got me thinking about how stunningly different flight training was from actually flying after I got my PPL. Here’s my comment, based on my first 9 years and 860 hours …

I agree: primary flight training has surprisingly little to do with what you’ll actually need to know to fly, unless your future flying is limited to taking flight tests and then working as an instructor.

I’ve met new pilots whose instructors have taught them that it’s “cheating” to use a GPS. Is it cheating to use the VOR receiver, then? What about the printed charts? I guess the trim wheel is cheating too, since it makes it too easy to hold the yoke. Pilotage and dead-reckoning are useful skills to learn and practice, but they should be maybe 10% of the navigation training for your PPL, not 90%. The 1930s were a long time ago.

You’ll always use a GPS for long cross-country flights, with or without backup from land-based navaids and your own pilotage (I still look out the window and mark my position and time on the VNC when I cross landmarks – it’s good to stay aware in multiple ways). You’ll use your GPS more than anything else in the plane besides the yoke, rudder pedals, and throttle; in fact, you’ll use it more than the throttle, which you might not touch for 4 hours on a long flight.

You’ll never sit down before a trip and put together a navigation log with the winds and groundspeed for every leg — that’s just a waste of time with modern flight-planning websites and applications. Instead, you’ll spend all that time worrying about your fuel stops: How late will the attendant be there (or will the self-serve pump actually work)? Are you cutting it too close for time/distance? If they’re fogged in, how far is the next one? Are there landing, handling, or ramp fees? Will the washroom be locked after 5:00? Can you get a taxi into town? Is there cell phone reception? How will you close your flight plan? Is there anywhere to get food?

You will learn to respect the weather like a medieval monk fearfully respected his God, and after many painful experiences over a few years, you’ll know more about weather than any ground school ever tried to teach you. At first, you learn to read what’s in the forecasts (GFAs, FDs, TAFs, etc.); eventually, however, you learn to read what’s not in the forecasts (“that much moisture north of Lake Superior means Marathon might be fogged in, even though it’s not forecast”; “I bet there will be a break in the storm line over the cool water of Lake Nippissing”; “I don’t trust the storms not to build up earlier with the winds blowing that way over the hills”), and that’s when you start flying well.

Posted in General | 11 Comments

My new autopilot in instrument conditions

This week, I gave my new autopilot its first workout in instrument conditions, climbing out through a low cloud layer in Ottawa, bumping through heavy rain clouds over Vermont and New Hampshire, and flying a localizer approach into Beverly Airport near Boston.

First, I’ll provide a bit of background. The autopilot has four modes as currently configured (without altitude support):

  • ST: stabilization mode, which keeps the wings level (or in a bank angle selected by rotating a small knob). In this mode, I can fly a hyper-stabilized plane, much like the over-simplified flight model in Microsoft Flight Simulator. Other autopilots sometimes refer to this as WL (wing-leveler mode).

  • HD: heading mode, which keeps the plane flying on a specific heading that I select using a bug on the heading indicator. The bank angle will vary as necessary to maintain the heading; for example, if I put the plane in a yaw using the rudder pedals, the autopilot will lower one wing noticeably to keep the plane flying in a straight line, and if turbulence knocks me off a heading, the AP will turn the plane to correct.

  • TRK (LO): VOR-tracking mode, which keeps the VOR CDI centered using a low-pass filter (that means that it reacts slowly, so that it’s not constantly zig-zagging when the VOR scallops, as they often do.

  • TRK (HI): localizer-tracking mode, which keeps the VOR CDI centred using more-aggressive corrections, as you’d want on an ILS or LOC approach, where it’s essential to stay right on the centreline.

The stabilization mode (ST) is virtually useless for me – I’ve enabled it only in my initial tests and in pre-flight checks. If I want to steer the plane using the autopilot, it makes much more sense to twirl the heading bug on heading indicator and have the AP follow it.

For enroute, I’ve tried both the heading mode (HD) and the VOR-tracking mode (TRK LO). The trouble with the VOR mode is that VOR needles scallop a lot back and forth, so even with the low-pass filter, the plane still gently weaves during flight. It’s nice because I can just set and forget until VOR passage — no heading corrections required — but especially in IMC, I found the heading mode much more effective. With gentle adjustments, I was able to keep the virtual CDI in my portable GPS perfectly centered, even in cloud and mild turbulence, sometimes going as long as 15 minutes without having to touch the heading bug.

I tried the localizer-tracking mode (TRK HI) for my localizer approach into Beverly. At 10 miles back, it didn’t seem to be doing a good job, sometimes allowing nearly a half deflection on the CDI, so I disengaged the AP before I got too low and flew the rest of the approach by hand (flying an approach in IMC isn’t a good time to troubleshoot). That might just have been an anomaly, though, and I didn’t test it inside the final-approach fix (FAF), when signal might be better — I’ll do a test flight on the ILS approaches in Ottawa in visual conditions to see how it performs there.

I’m learning to deal better with the lack of altitude hold. On my first couple of flights, I was trying not to touch the yoke when it was in HD mode, and instead to correct altitude deviations using the trim. Even though I worked hard to damp out oscillations (anticipating them by trimming before the pitch reversed direction), it was still a challenge in turbulence.

On my Boston flight in IMC, I took a different approach, and tried sharing the yoke with the AP: I pulled or pushed it to control pitch and then trimmed to relieve pressure (the way I normally would), but managed to get used to letting the AP still turn the yoke while I was holding it. I was able to trim more effectively that way, and didn’t have to correct as often, even in turbulence.

The big conclusion, though, is that the AP made a huge difference in fatigue. I can (and have) hand-flown harder and longer flights in instrument conditions, but I’m very tired after I land from the constant second-to-second attention required for the scan and other IFR tasks. The autopilot let me relax a little bit, study the approach plates more carefully, pay more attention to the engine gauges (which can slip out of an IFR scan, when keeping the plane upright is the main concern), and just generally relax, while still keeping an active (but less frenetic) scan.

Posted in General | 3 Comments

Adding an autopilot

Today I flew my plane home from Waterloo to Ottawa with a brand-new autopilot installed.

I’ve flown over 850 hours, about 120 of them in actual instrument conditions, and all by hand. I’m proud that I can do that, but at the same time, it’s tiring: after 8 hours bumping around in cumulus clouds and dodging storms on the Stormscope, I’m exhausted beyond anything I’d ever imagined. Even 4 hours in good VFR weather can be tiring, because of the constant attention needed to keep the plane straight, level, and on course.

Choosing an upgrade

I knew it was time to improve rather than just maintain my plane, and I also considered an IFR GPS and a new paint job (both about the same cost), but the autopilot gave me the biggest safety and operational benefits for the money. I called a few places for quotes, but the only one that answered my calls and questions consistently was Kitchener Aero, where owner Barry Aylward went out of his way to carry on a friendly e-mail and phone correspondence for half a year while I hemmed and hawed, then fit me right in as soon as I made up my mind, as if I were one of his bizjet customers rather than a tight-fisted Cherokee owner.

I decided on the S-TEC System 20, a rate-based autopilot (much smoother and more reliable than old APs) that is built into a turn coordinator, and replaces that instrument on my panel without needing any extra space. The S-TEC 20 is a single-axis autopilot — that means that it controls roll (and heading), but not pitch (and altitude) or yaw. Barry warned me that I’d wish I’d paid a few thousand extra for the S-TEC 30 with altitude hold, but I was already close to my spending limit, and knew I’d end up asking for extra maintenance work on my existing avionics (and a new 406 MHz ELT, since the plane was there anyway …).

Using the autopilot

Kitchener Aero sent me up on a test flight with one of its people, ready to adjust the autopilot, but it was absolutely perfectly tuned. While the S-TEC 20 can’t hold an altitude, here’s what it can do:

  • Keep the wings level, and allow simple, stable turns using a knob (without risk of overbanking).
  • Track a heading set on my heading indicator.
  • Track a VOR radial inbound or outbound.
  • Track a localizer on a LOC or ILS approach.

We were able to try all of these during the test flight northwest of Waterloo (except for the LOC tracking, due to a miscommunication with Waterloo tower). Unlike GPS tracks, VOR needles tend to scallop — wag back and forth — and an autopilot that overreacts to that will soon make the passengers (and pilot) seasick with all the rocking. The S-TEC 20 responded very gently, and almost unnoticeably, to the scalloping, even close to the VOR.

First cross-country with an autopilot

During my flight home, I had a chance to use both modes for a bit over two hours. I used VOR-tracking mode to track northeast outbound from Waterloo, then heading mode (with frequent adjustments) to fly a DME arc just outside Toronto terminal airspace until I could join my airways, then back to VOR-tracking mode as I followed the airways and switched from VOR to VOR. Up at 9,500 ft, above the broken layer of cumulus cloud, the air was smooth as silk, and I was able to fly hands off with only an adjustment every 5 minutes or so to the elevator trim to hold altitude. Barry was wrong — I wasn’t missing altitude hold at all.

Unfortunately, summer is summer, and eventually, the cloud layer rose up to meet me. I had to descend down below it, and my nice smooth flight became a mechanical rodeo bull. The autopilot still did a good job holding heading and tracking the VORs, though the turns in turbulence were more aggressive and noticeable, but I found myself trimming every 30 seconds or so as my pitch and altitude shot up and down in rising and falling air columns. Barry was right — in the turbulence, I wished I had altitude hold.

The good news is that the S-TEC 20 can easily be upgraded to an S-TEC 30, which does support altitude hold and electric trim. Maybe in a year or two.

Next steps

I think the autopilot is going to be a big part of my flying from now on. I’ve enjoyed the bragging rights of always hand-flying, but 9 years of bragging is enough. Besides, if flying is less tiring, maybe I’ll do more of it, and travel further: the prairies, the Arctic, the Mississippi, even the Florida Keys and the West Coast are all out there waiting for me.

Posted in General | Tagged , , | 13 Comments

Hiatus and Return

I took a six month break from flying — basically, work, a long wait for new fuel caps at my annual, and a family vacation in London (UK) got in the way. I also managed to prove the third rule of aviation (after the large-fortune and old-bold pilots ones):

You can have enough time to fly, or enough money to fly, but not both.

Changes in work

Consulting work has been wonderful crazy busy for me and pretty-much every other consultant I know, whether in IT, business, aid work, development, or what-have-you. Canada barely got brushed by the recession that devastated the US in 2008-09 (with record-high property prices in most of our big cities, it may be that our bubble just hasn’t burst yet). The problem is that my customers are mostly in Canada and the UK now — the US economy isn’t so great, remember — so I don’t have work excuses to fly down to Boston, NYC, Washington, etc. like I used to.

Recency Lost

I’ve never taken such a long break before. After six months away from flying, bad things start to happen:

  • You can’t fly IFR, because you have to have done six hours real/simulated IMC and six approaches within the last six months (the infamous 6-6-6).
  • You can’t carry passengers at night, because you have to have done five takeoffs and landings at night within the last six months.
  • You can’t carry passengers during the day, even other pilots, because you have to have done five takeoffs and landings (any time) within the last six months.

Recency Regained (part 1)

So now it’s a matter of crawling my way out of the hole, milestone by milestone, until I can get back to my regular IFR/cross-country kind of flying. I started by calling my flying buddy Mike Hopkinson and asking for an intervention, and he complied by texting me last Saturday to remind me to get to the @#$% airport and then meeting me after his shift on dispatch. I uncovered the plane, made some stupid mistakes trying to start it (yes, it does help to check the fuel cutoff), recharged the battery that I drained, then did my normal post-maintenance checks:

  • Long, thorough preflight, including control movements.
  • Confirm that the engine compartment is clean (I even took a picture for before/after comparison).
  • Do a 5-minute lean ground-runup, and watch for anomalies.
  • Do a high-speed taxi down the runway to check what happens as the controls become effective.
  • Shut down and search for stains, leaks, cracks, or anything else that shouts DON’T FLY!
  • Start up again and fly circuits, always within gliding distance of the runway.
  • Shut down and repeat the stain/leak/crack checks.

The plane passed with flying colours (so to speak — my paint scheme is drab), and I managed five touch-and-go landings in a crisp cross-wind, progressing from “what-the-hell-was-that?” on the first to “now I’ll gently lower the nosewheel exactly on the centreline” on the fifth. It turns out the the rules make sense — 5 really is the magic number, and now I was legal to carry passengers in day VFR.

Victory lap to Toronto and back

As soon as I was done that and mentioned it on Facebook, my older daughter asked me if I could pick her up in Toronto and bring her home for a break from her studies at U of T. It grated to be a VFR-only pilot, but the weather on Friday co-operated beautifully, so I managed to get 4 hours of proper cross-country flight time (3.6 hours air time) on a beautiful spring day. I was ridiculously nervous beforehand, but on the day of, my flying and radio work through the busy Ottawa and Toronto airspace was fine, and the flight was as boring and uneventful as I want all my flights to be (my rule is that the only excitement in flying should come from the scenery outside the window). No new milestones from that flight, but I feel confident now to start back into the night and IFR work — 2 more milestones to go.

Posted in General | Tagged , , , , | 3 Comments

Calls for violence

Protesters throwing molotov cocktails in Thailand.At OurAirports, an anonymous visitor has left the same comment for six different Vietnamese airports (including an air force base), encouraging a Libyan-style uprising in Vietnam (the comments should be gone by the time you read this, for reasons that will become clear below). According to Google translate, each comment begins something like this:

Other ways to protest that a person can do.

Libyan people using violence to overcome violence, ONLY NEW VIOLENCE AGAINST THE VIOLENCE.

Please all the people of Vietnam Hero follow Libyan people:

Gasoline burn all government buildings, the gas plants, the tank cars carrying fuel, the homes of Communist Party members Hunting Dogs.

Each comment then goes on to provide detailed instructions with different ways of making and using Molotov cocktails. My approach to comment moderation on OurAirports is fairly permissive — I’m happy to leave in comments with strong language, political views, or even scammers trying to defend themselves (it’s fun to see other commenters take them down). I will not, however, allow comments encouraging violence, and even more importantly, I won’t allow comments that include weapon-making instructions.

In a wonderful bit of unintended irony, each comment ends like this:

The U.S. government declared, would send U.S. troops to guard the people’s protests, the people in countries with rebel demands to overthrow dictatorships.

The United States — saviour of the Vietnamese people?

Posted in General | Tagged , , , | 7 Comments

6th anniversary of Land and Hold Short

I started this blog on 1 October 2004, with a typical welcome-to-my-blog posting. Thanks to everyone who’s been reading over the past six years.

Posted in General | 4 Comments

8 years as a licensed pilot

Eight years ago today, on 29 August 2002, I passed my flight test and earned my Private Pilot License — Aeroplane (PPL). I had 56.9 hours in my logbook (14.1 solo), and took the flight test late in the afternoon in rented Cessna 172P C-GPMR after the examiner, Bill Gadzos, finished his shift in the Ottawa Airport control tower.

Whee! I’m free!

Over the next month, I took with a few short flights in rented C-172s to celebrate my newly-won independence: to Kingston Airport to fly my parents around on 6 September, to Morrisburg Airport on 13 September, to Smiths Falls Airport on 18 September, to Peterborough Airport on 25 September, and finally, with my kids and my spouse’s cousin Andrea, over Arnprior Airport and back on 29 September.

But is it useful?

After only a month, however, the excitement of flying same-day trips within an hour of Ottawa in a rented plane was wearing very thin. I wanted flying to be useful, and to get to that point, I needed three more things:

  1. A night rating, so that I wasn’t restricted to daylight flying
  2. An instrument rating, so that I wouldn’t be grounded for days in bad weather
  3. My own plane (or a share in one), so that I could go on real trips for business or family vacations

Student again … and owner

So barely a month after earning my PPL, I had my instructor, Alain Mussely, back in the right seat working with me on my night and IFR ratings. I went airplane shopping at the at the Buttonville Airport in November 2002 and decided to buy a 1979 Piper Warrior II (C-FBJO) — a low-maintenance, fuel-efficient plane that can cruise at 125 knots true airspeed for six hours (no reserve) with a 665 lb load. The plane arrived in Ottawa on 4 December 2002 for an extensive pre-purchase inspection, then I put it into the shop to have a four-place intercom installed over Christmas.

I earned my night rating in February 2003, and my instrument rating in July 2003, and then I had everything I needed. A couple of long trips before the instrument rating had convinced me of its value: I got stuck overnight at North Bay Airport because of bad weather on a flight back from Sault Ste. Marie in May 2003, and had to race out of Caldwell Airport near New York City in June 2003 in the wee hours of the night to escape ahead of 3-4 days of bad weather.


On 28 July 2003, I took my family and dog up for our first cross-country IFR flight. It was gloomy on the ground under a low overcast, and it was strange for my family inside the clouds when everything outside the windows went white, but then suddenly we burst into brilliant sunshine and blue skies. 11 months after earning my PPL, I finally had everything I needed to make flying useful. I have 750 hours’ more experience now, but I still have the same license, the same plane, and the same ratings.

Posted in General | 2 Comments

Search and Rescue near Algonquin Park

Emergency Locator Transmitter

A typical ELT.

I had an unusual experience this morning flying home from Sault Ste. Marie to Ottawa with my dog, Paisley. Three separate high-altitude jets heard an ELT signal at a point along my route about 20 miles south of North Bay.

The most common types of ELTs will start sending a signal automatically when they experience high G-forces (such as when an aircraft has made a forced landing or crashed), but most often, an ELT signal just means that a boat has bumped against a floatplane, someone forgot to turn off an ELT in the back of a courier truck being shipped back for a battery changed, etc. etc. It used to be that satellites monitored the emergency frequency 121.5 MHz, but they don’t do so any more (they’ve switched to the new 406 MHz frequency), so it’s up to us pilots to listen and report.

Joining the search

There was already a plane or helicopter with the callsign “Rescue 333” doing a lower-level visual and ELT search. It also happened, however, that Toronto Centre was already talking with two small planes at lower altitudes who would both be crossing the location where the signal was received: me from west to east, and a Cessna 172 from south to north. Centre enlisted both of us to widen the radio-search area by tuning in 121.5 MHz on our second radios and listening for any signal as we passed through. Every 3-5 minutes, I turned off the squelch on my radio: that creates horrendous static, but it also lets me hear very faint signals.

None of us, including the search aircraft and other high-altitude airliners, heard anything more. I looked as carefully as I could, but from 9,500 ft in a low-wing aircraft it’s hard to see much detail, and I didn’t want to go lower and interfere with the Rescue aircraft’s search patterns.


About 20 minutes later, over Algonquin Park, however, I did suddenly hear one very brief ELT wave (the part that sounds like a sheet of metal pinging), as if someone had switched an ELT on to test it then turned it off a second later. It was 8 minutes after the hour. All ELT testing is supposed to take place during the first five minutes of each hour, but I suspect that some floatplane pilot somewhere in the park just had a slow watch. Still, I reported what I heard to Centre, and they passed it on to the Rescue plane.

How to help

The odds are very high that this was a false alarm — most search and rescue calls are — but it was still sobering to think of a brother or sister pilot down there somewhere under the tree canopy, in desperate need of help. If you’re a pilot with two radios, I strongly suggest that you keep the second tuned to 121.5 MHz whenever you don’t need it to get weather, etc. — some day you might actually make a difference.

Posted in General | Tagged | Leave a comment