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Encouraging People to Replace Us

Finding young people to grab the reins from us old guys in aviation is a bit like the weather … everyone talks about why we need to do something, but not everyone is clear about how to actually make that happen. Certainly doing nothing is the wrong answer. So what can we do to increase our odds of connecting all the right people together?

NBAA 2015 yoproAt the recent NBAA convention, the association offered a number of us an opportunity to mingle with a hundred or so officially named Young Professionals who’d volunteered to listen to us more-experienced (secret code for older) industry folks detail how we started while also delivering a bit of unsolicited advice for job seekers.

The NBAA team was spearheaded by the association’s Sierra Grimes with Brett Ryden from Southcomm’s Aviation Pros.com leading a group of his editors who together created an hour’s worth of practical education at the show’s Innovation Zone. The panel was evenly split between ladies and gents … myself, Jo Damato from NBAA, Sarah Barnes from Paragon Aviation and Textron Aviation’s senior VP of Customer Service Brad Thress. Our moderator was writer Lowen Baumgarten.

Stage members spent a few minutes detailing their experiences, but since we were there to answer questions, I was antsy to interact with the audience. Over the course of the hour there were perhaps seven or eight good ones, but I wanted more. I probably shouldn’t have.

Reality kicked in for me about 20 minutes after we began as I realized that some of what a number of young people had told me the night before was really true … networking is not an innate skill, not even close. I’d seen this kind of thing before too. Universities apparently assume graduates automatically absorb networking skills out of thin air I guess. Continue reading

Big Watches, Fuel Gauges, and Annunciator Lights

The notion that engines run on air is no more absurd than attempting flight with insufficient fuel in a tank connected to the engine. Yet hardly a week goes by that somewhere a pilot is attempting to go where none have gone before.

The technology of measuring fuel has gotten much better than the wire and cork device used on the Piper Cub. The Cub’s design was stone simple—mount the fuel tank directly in front of the pilot (not such a great idea from a crashworthiness perspective, but only a short hose run to the engine) and attach a cork to the end of a wire rod. The length of rod protruding through the fuel cap indicated how much go-juice remained. Only two things could go wrong: The cork could become saturated and sink, giving the pilot a sinking feeling that no fuel remained, or worse, the rod could become slightly bent and jam, falsely indicating more fuel on board.

We paid little attention to any of that and always used our big pilot watches to determine how long to stay aloft. Time is one of the best indications of what’s left in the tank(s), provided you know what was on board to begin with and are familiar with the engine’s burn rate—both highly recommended procedures.

New pilots are often told that the fuel gauges on light aircraft are unreliable and that the FAA only requires them to be accurate in one condition—empty. Let’s dig into that a bit more. As usual, there seems to be some gray!

Under CAR 3.672 Fuel Quantity Indicator, the Civil Air Regulations by which most legacy aircraft are certificated, “Means shall be provided to indicate to the flight personnel the quantity of fuel in each tank during flight…Fuel quantity indicators shall be calibrated to read zero during level flight when the quantity of fuel remaining in the tank is equal to the unusable fuel supply as defined by § 3.437.” [ital. added]

Under the new regs, FAR 23.1337 Powerplant Instruments Installations—(b) Fuel quantity indication, “There must be a means to indicate to the flightcrew members the quantity of usable fuel in each tank during flight. [ital. added] An indicator calibrated in appropriate units and clearly marked to indicate those units must be used. In addition: (1) Each fuel quantity indicator must be calibrated to read ‘zero’ during level flight when the quantity of fuel remaining in the tank is equal to the unusable fuel supply determined under § 23.959(a)…” It’s not appreciably different from the earlier rule.

It could be reasonably argued that quantity indications should be accurate but sometimes the hardware is suspect. The FAA goes on to say in a safety publication, Time in Your Tanks—P-8740-03, “Fuel gauges are subject to malfunctions and errors. Therefore, unless restricted by the gross weight or center of gravity limits, it is considered good judgment to ‘top off’ the tanks at fuel stops. If the fuel load must be limited, you should endeavor to get an accurate measurement of fuel quantity by using a dipstick calibrated for the aircraft.” Dipsticks are a good measure…IF…they are properly calibrated…AND…the aircraft is sitting level, which allows Murphy’s law to slip in.

With the “rebirth” of GA in the ’90s, most manufacturers added low-fuel annunciator lights to new production aircraft (a.k.a. fuel “idiot lights”—they have been installed on most automobiles and larger aircraft for decades) separate from the gauging system to make it really hard to run the beast out of fuel or a tank dry. In general, it’s worked very well although one young CFI and his student managed to run a new production Cessna, equipped with lights, out of fuel. No need to belabor the point where I’m sure both participants will do better in the future. The fuel accident numbers of new tech aircraft compared to the classics is much better and it’s not because pilots suddenly got smarter.

But suppose you own a classic, and installing annunciator lights is prohibitively expensive. A highly recommended upgrade, second only to installing shoulder harnesses, is to install a fuel flow transducer/totalizer which will accurately measure fuel flow to within a few tenths of a gallon. As for quantity, it must be properly programmed, so it’s not quite as goof-proof as the low fuel lights. Used on every flight, it provides great peace of mind—either more fuel is required or it isn’t. As far as not running a tank dry, a timer or that stopwatch function on your chronograph or some other clock on board should help.

Back to the FARs—Do the gauges need to be accurate or not? In my view, it’s irrelevant. The Air Safety Institute’s “Golden Hour” approach of always landing with one hour of fuel on board elegantly solves the problem.

 

Holiday Volunteer Pilots Needed in Michigan

Have you ever wanted to play Santa Claus in your personal Cessna, Piper, or Beech sled? Well here’s your opportunity to spread Christmas cheer across the State of Michigan!

For more than 40 years, Operation Good Cheer has made a difference in the lives of foster care children living in all corners of Michigan.  “OGC” as it is referred to locally has brightened the holiday season for more than 5,200 children using 70 social service agencies, 290 sponsoring individuals, families, and companies, 20 trucking companies and 25 community airports. And — nearly 300 aircraft and hundred of general aviation pilots!

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If you happen to be one of the goodhearted pilots with an interest in serving the community on Saturday, December 5th — read on! Your help is needed for the “Spirit of Good Cheer” flight which brings the gifts from Oakland County International Airport to airports and deserving children across the State. Does your plane have a turbine? Maybe a propeller? Are you instrument rated? Or not?  Those are all minor details as all licensed pilots of any aircraft are welcome to join the team!  If you are interested, take a look here for information on the airport, the procedure, and to RSVP to give the team a heads up that you are coming: http://www.cfsm.org/spirit-of-good-cheer

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I have participated in OGC several times and I can say its one of the best times I’ve had while flying.  The team, the pilots, and the children are all upbeat, happy, and helpful.  So, if you have some time considering donating some of your time — you won’t be disappointed!

 

Why I fly high

I take a lot of long trips in my Cessna T310R, and more than half of them involve cruising up in the high teens and low Flight Levels, simply because those are the altitudes at which my airplane is happiest, fastest, and most efficient. But from what I’ve been able to tell, the great majority of piston pilots shy away from using the high-altitude capabilities of their airplanes. Most pilots of normally aspirated airplanes seem to confine most of their flying to altitudes of 10,000’ and below, and even many pilots of unpressurized turbocharged airplanes like mine have never flown in the Flight Levels. It’s even surprising how many pilots of pressurized birds seem averse to flying much above the low teens.

That’s a shame, because it’s at the high end of the altitude spectrum that most of our airplanes achieve their best efficiency—and in many cases, their best speed as well. I’m not just talking about turbocharged airplanes. Most normally-aspirated birds are perfectly capable of cruise altitudes well into the teens.

Look at a plain-vanilla, fixed-gear, normally-aspirated Cessna Skylane:

Cessna 182Q Range Profile

Cessna 182Q Skylane range profile page from POH.

At a low altitude like 4,000’, maximum cruise speed is 139 KTAS at 75% power. Continue climbing until the airplane “runs out of throttle” at 8,000’ and max cruise climbs to 144 KTAS. That extra 5 knots will save you 9 minutes on an 800 NM trip when you take the extra climb into account. (5:38 instead of 5:47, no big deal).

Continue climbing to 12,000’ and max cruise drops back to 139 KTAS (same as at 4,000’), but at a much more fuel-efficient 64% power (which is all you can get at that altitude with wide-open throttle). The same 800 NM trip will take 6 more minutes at 12,000’ than at 4,000’ (5:53 to be exact) because of the longer climb, but burn a whopping 12 gallons less fuel in the process—if avgas costs $5/gallon, that’s $60—and increase IFR range by a full hour and 130 NM!

How far can we take this? Don a cannula and climb to 16,000’—high enough to fly right over the Front Range of the Rocky Mountains IFR—and max cruise drops to a still-respectable 130 KTAS at a miserly 53% power. Because it takes a Skylane nearly 40 minutes to climb from sea level to 16,000’ at max gross, the 800 NM trip will take a half-hour longer than at 12,000’ (6:23), but will save 20 gallons ($100?) and increase IFR range by a full two hours compared to our 4,000’ benchmark.


Cruise
Altitude
Max
Cruise
IFR
Range

To fly an
800 NM Trip

4,000 139 K 820 NM 5:47 78 gal
8,000 144 K 840 NM 5:38 79 gal
12,000 139 K 950 NM 5:53 67 gal
16,000 130 K 1,040 NM 6:23 59 gal

Normally-aspirated, fixed-gear 182Q
(maximum gross weight, standard day, no wind,
88 gallons, 45 min reserve)


Unless you just happen to like low-and-slow, there’s no logical reason to cruise a Skylane lower than 8,000’ because doing so makes all the numbers worse: cruise speed, trip time, and range.  On the other hand, climbing to 10,000’ or 12,000’ will cost you a negligible amount of time, and reward you with substantially lower fuel burn and increased range.

These calculations are all based on zero-wind, but in real life the winds aloft are often a decisive factor in determining the best altitude to choose. If you’re headed eastbound, odds are you’ll have a tailwind—and the higher you fly, the better it’ll be.

In wintertime, climbing up high to catch favorable winds can pay off spectacularly. In the low-to-mid teens, 50 knot tailwinds are commonplace and a 70 or 80 knot tailwind is possible. Even in summer, when winds tend to be relatively light, going high can pay off. Here are some typical summer winds I pulled off of DUATS:


      6000    9000   12000   18000
 STL 2410+18 2809+12 3110+07 2917-04
 SPI 2510+18 3010+12 3211+07 2919-05
 JOT 2511+17 3012+12 3116+06 2926-07
 EVV 2509+17 3012+11 3216+07 3018-05
 IND 2411+16 3011+11 3114+07 2922-06
 FWA 2312+15 2812+10 2916+06 2926-07
 CVG 2210+15 2809+11 3012+07 3021-05
 CMH 2210+14 2710+10 2914+06 3026-07
 CRW 2108+15 2509+10 2908+06 3225-05
 AGC 2010+12 2510+09 2813+05 2930-09
 EKN 1907+13 2608+09 2810+06 3028-07
 PSB 1911+11 2509+08 2813+04 2930-11
 EMI 9900+11 2905+09 2811+05 2927-10

Even in these docile summertime conditions, we can expect 10 to 15 knots more tailwind component at 16,000’ than at 8,000’, which almost exactly offsets the TAS advantage of the lower altitude (144K vs. 130K). By climbing up high on an eastbound trip, we’ll go just as fast, burn considerably less fuel, and increase our IFR range nearly 400 NM! Not to mention that it’s almost always smoother and cooler up high. What’s not to like?

During the winter, when the winds tend to be stronger, going high on eastbound trips tends to be an even better deal, saving both time and fuel.

For turbos, it’s even better

If you’ve got a turbocharger, the argument for flying high becomes compelling, because the higher you fly in a turbo, the higher your speed, range and efficiency—at least up to the low Flight Levels in most turbocharged airplanes. These birds really shine up in the high teens and low twenties, and pilots who don’t take advantage of this capability don’t know what they’re missing.

For example, take a look at the “Range Profile” page for my Cessna T310R:

Cessna T310R Range Profile

Cessna T310R range profile page from POH.

Starting at 180 KTAS at sea level, max cruise speed at 73.6% power steadily increases with altitude to a relatively blistering 221 KTAS at FL200. (Above that altitude, available power starts dropping off fairly rapidly.)


Cruise Altitude Max
Cruise
IFR
Range
To fly an
800 NM Trip
5,000 190 K 860 NM 4:14 143 gal
10,000 199 K 890 NM 4:04 137 gal
15,000 209 K 930 NM 3:55 131 gal
20,000 221 K 970 NM 3:45 125 gal

Turbocharged, twin-engine Cessna T310R
(73.6% cruise, maximum gross weight  standard day, no wind,
163 gallons, 45 min reserve)


At the same time, range with IFR reserves climbs from 820 NM to 970 NM. Naturally, trip time and fuel burn for the proverbial 800 NM trip both drop accordingly—from 4:14 and 143 gallons at 5,000 to 3:45 and 125 gallons at FL200.

Personally, I don’t push my engines this hard. I almost always throttle back to between 60% and 65% power and settle for around 205 KTAS at FL200 at a miserly fuel burn of 26 gallons/hour, giving me a range of well over 1,000 NM with IFR reserves (or 1,200 NM if I fill my 20-gallon wing locker tank).

Once again, these figures assume no-wind conditions. Add in the wind on an eastbound trip and the results can get downright exciting. In the winter, I’ve seen my groundspeed edge above 300 knots from time to time. That’s fun! During the summer, on the other hand, I’m happy with 230 or 240 on the GPS readout.

Needless to say, you pay the piper going westbound. But if the winds aren’t too strong, it may still pay to go high rather than low. In my airplane, I gain 22 knots of true airspeed by climbing from 10,000’ to FL200. So if the headwind at FL200 is only 10 or 15 knots stronger than at 10,000’ (which is usually the case in summertime), higher is still better.

In wintertime, of course, westbound aircraft are all in the same boat, turbo or non-turbo. We bounce along at the MEA, try not to look at the groundspeed readout, hope the fillings in our teeth don’t fall out, and think about how much fun the eastbound part of the trip was (or will be).

Enjoy the high life!

If you’re one of those pilots who comes from the “I won’t climb higher than I’m willing to fall” school, you’ve got nothing to be embarrassed about. Believe me you’ve got plenty of company. But you’re also missing something really good.

Do yourself a favor: give high a try. It’s cooler and smoother up there. Your airplane flies faster and more efficiently up high. ATC will usually give you direct to just about anywhere. You’re above terrain, obstructions, and often the weather and the ice. The visibility is usually terrific. So are the tailwinds, if you’re lucky enough to be going in the right direction. Try it…you just might like it!

Wearing your uniform in public

womens-pilot-shirts-MZAny pilot or flight attendant will tell you that being in uniform—especially at an airport—can be a trying experience.

Airports, especially mega-plexes, can be confusing and disorienting places, and travelers will look for anyone who remotely looks like they know—well, anything. And the pilot uniform  is a magnet for attention, some of it not so positive.

The most common question is usually along the lines of finding gates or baggage claim. Somehow, this always seems to occur whilst standing right under a sign for the wanted location, but hey, who’s checking? In larger airports with international flights, the uniform becomes a sort of universal sign of someone who might be able to help, especially if the person asking is in a bit of a panic.

Some of the questions are technical, wanting to know how or why things happen the way they do, either on the ground or in the air. These are fairly simple to answer, and often they are actually fun conversations.

But the most difficult situation to deal with is the individual (or worse, a group) who approaches and starts to berate you because of a travel experience that has not gone smoothly. If the red face and flying spit don’t give it away, the opening line of “Your company sucks” usually does.

My advice is to let the person vent for a bit, and, if necessary, ask a question or two that will help narrow down the area of complaint. At that point, you might be able to offer the appropriate words of consolation and help. In my experience, I find that when conversations start this way, it’s because of a lack of information provided to the customer (or the customer was not around when the information was disseminated). Sometimes you’re simply not going to be able to help, and the best you can do is to offer some empathy.

Another tack might be to get as much information as possible, and then walk with the customer to a gate or service counter and explain in succinct terms what the individual needs.

Oddly enough, it seems like passengers also have a hard time believing that we are not intimately familiar with everything. More than once, I’ve been asked questions about a particular airport or city, and folks are surprised to learn that it might be my first visit there as well. When it’s a hub airport, they are even more incredulous, but all I can do is politely explain the situation and try to help as best I can.

The most important thing to remember when wearing in your uniform in public is that from the minute you walk out your door to the minute you walk back in, you are a representative of your company, and, on a larger scale, your industry. This is true of any uniform, but it bears repeating, because the airlines are an industry that everyone loves to hate.

Remember, your uniform is a great way to both show off and smooth out some ruffled feathers. Use that to your advantage. Realize as well that some will make note of your name from your ID or name tag. If they are going to write the company about their exchange with you, do what you can to make it a positive communication. Whether you like it or not, you become who your uniform says you are, no matter where you are.—Chip Wright

Lake Hood Master Plan Alternatives Survey

The Lake Hood Seaplane Base is in the process of updating it’s Master Plan, the document which will guide development of the airport for the next ten to twenty years.  The process involves planning staff and stakeholders reviewing issues, current use and future projections for the airport, and developing alternatives for projects to maintain and/or expand the facility. At this stage, alternatives have been developed, and a user survey is underway to rate the alternatives developed by the planning team.  Options range from maintenance of existing facilities, to candidate projects that could significantly expand the capacity of the airport. For more information about the plan, which is about halfway through a two-year schedule, see the LHD Master Plan website.

Whether you are a local or transient user of Lake Hood, consider taking the online survey, designed to help set priorities for the proposed alternatives identified. The survey has links to color maps, showing the locations of different elements of the plan.  It contains about 50 questions, so you might grab a cup of coffee and prepare to devote a little time to working through the the options.  Click here to take the survey, which runs through December 7, 2015.

lake hood mp graphic

Lake Hood is is purported to be the world’s largest seaplane base, and is the home for some 800 aircraft.  With the water lanes and gravel runway, it serves both seaplane and wheel traffic, often topping 400 operations a day in the summer.  This general aviation airport (exclusive of neighboring Anchorage International Airport) is estimated to have an economic impact of $24 million to the Anchorage community. In addition to being home for private pilots, air taxi operators, maintenance and parts businesses, it has an aviation museum, several government aircraft bases and a Civil Air Patrol maintenance facility. It is also home to the Alaska Airmen’s Association.

If you care about this facility, take a few minutes and provide some feedback to help guide the future of this Alaskan crown jewel.

Heads Up: VIP NOTAM issued for Anchorage

Heads up for pilots flying in the Anchorage area this Sunday afternoon, November 22, 2015. A VIP NOTAM has been posted for the time interval from 2 to 5 pm, limiting flights within 30 nautical miles of JBER. Like the Presidential TFR from last August, there is an inner and outer ring, each with different restrictions.

Remember, the details and times may change, so be sure to check NOTAMs before you take off (and while enroute) for the latest information.  http://tfr.faa.gov/tfr2/list.html

Graphic depiction of the VIP TFR NOTAM. Make sure and check for updates, in case it changes.

Graphic depiction of the VIP TFR NOTAM. Make sure and check for updates, in case it changes.

First officer responsibilities

DC10ChecklistEveryone knows that (almost) every professionally flown airplane has two pilots up front, and the captain is in charge. He or she gets paid the big bucks to make all of the hard decisions and take all of the glory when things go perfectly smoothly.

What are the first officer’s responsibilities?

First, every first officer hates the word “co-pilot,” because that is not the proper term. But moving on.

At the most basic level, the FO is there in case anything happens to the captain. Twice in 2015, airline flights have diverted because of a medical issue with one of the pilots. In one case, the captain died. This is obviously not the norm, but it is a possibility, and with the increase in mandatory retirement age from 60 to 65, it’s not unreasonable to expect that more events like this might occur.

From a duty standpoint, the FO does more than recite checklists and move the lever for the landing gear. Just about every airline and flight department allows the captain to “delegate” certain duties to the FO, and in most cases, it becomes a working assumption that the FO will fulfill these duties. Delegating, per se, doesn’t have to occur. For example, the walk-around is almost always conducted by the FO, and when the weather is lousy, you can pretty much guarantee that the FO will be the one trudging around in the rain and snow to check the outside.

In an environment like the airlines, in which the crew is monitoring two radio frequencies on the ground, the FO will handle most communications on the company “Ops” (for Operations) frequency. This is the frequency used for all non-ATC issues, such as late-arriving wheelchairs, two passengers being assigned to the same seat, catering issues, et cetera. The captain might jump in for a maintenance issue, but the FO usually handles these as well.

In the corporate world or in operations with no flight attendant, the FO is often responsible for tidying up the cabin, disposing of trash, and the like. Fetching paperwork often falls on the FO as well, though at some companies the captain takes care of this so that he or she can review the fuel load and weather with the dispatcher.

In the airplane, crews typically rotate turns flying, and there is no difference in the way the airplane is handled or flown, no matter who is flying. If it’s the FO’s leg, and he wants to deviate 20 miles for weather, then the deviation takes place. The FO generally will run the checklists while taxiing, because the captain is the only one with a steering tiller, but once airborne, the flying pilot is the flying pilot. If something goes awry, company procedures may dictate who does what. Most but not all airlines will allow the FO to continue flying if an emergency develops during the FO’s leg. That said, some situations may arise that require the captain to fly. This is usually a result of aircraft design, and it is not a reflection of the ability of the FO to fly. Nonetheless, the captain always has the option to take over if he or she believes that is the best course of action.

First officers often comment that they work much harder than the captains, and it’s a comment that is actually fairly accurate. FOs often get the grunt work in addition to routine duties. Fair or not, it’s just the way it is, a means of paying the dues. It’s also a learning experience. But when push comes to shove, the FO has just as much authority to question something as a captain does, and if there is something wrong that can only be found on the walk-around, the captain is counting on the FO not only to do the job, but also to do it well.—Chip Wright

The science of building/maintaining aircraft

young mechanic (1)

Building and maintaining aircraft is mostly science and perhaps a bit of art. There should be a keen awareness on the tradeoff made between affordability, suitability, and safety. If it’s a homebuilt and you built it, than who knows better than you on how to maintain it? That’s somewhat debatable and while the amateur-built regulations give us plenty of rope with which to hang ourselves, there are some best practices that should be taken as gospel. Many have been learned the hard way.

A few observations:

Hot Seat—Understanding amperage, circuit breakers, and good wiring technique is more than just a good idea. A homebuilt flying the Everglades some years ago in visual conditions asked ATC if they were aware of any fires in the area. ATC knew of nothing, but the pilots soon discovered that the automotive electric seats they had installed had turned into hot seats. Unfortunately, the plunge into the swamp was fatal and the NTSB noted that a circuit breaker supposedly protecting wiring and accessories from a short circuit, didn’t. We can discuss the wisdom of electric seats in homebuilts but wiring practices are really non-negotiable. It was high price to pay for a bit of ignorance.

Hose Clamps—Another fatal accident occurred when a mechanic decided to use an automotive hose clamp to secure a muffler and exhaust pipe on a Piper Cherokee, resulting in an in-flight fire. The aircraft version, while about 15 times more expensive, had a critical detail that the mechanic apparently overlooked or thought unimportant. There is a pin on the clamp, which is inserted into a hole in the muffler and exhaust pipe and holds the two together even if the clamp loosens. Some parts of aircraft really do need to be expensive and well-made.

Plumbing—A recent honest mistake apparently involved the builder of an RV-10 who suffered an engine stoppage due to fuel starvation. There is currently a $35 million lawsuit pending against Vans Aircraft and the manufacturer of the fuel flow transducer that the NTSB reported was plugged by an improperly-used sealant in the system. There was loss of life so the legal system is involved. Sometimes that’s warranted but this has little, if anything, to do with Vans in my view.

There is a long thread on Vans Air Force that looks at the pros and cons. One of the writers thoughtfully points out that there is perhaps not enough guidance on what and how one should specifically assemble various parts and pieces. In my two earlier examples, it seems the guidance was pretty clear and the crux of this suit may hinge on what the builder knew and when he knew it. How much guidance should a manufacturer for a kit or a component provide, and does that incur additional liability? Is it their responsibility to educate builders on everything that a certificated mechanic should know? Guess a jury will sort that one out.

One thread respondent points out that in too many cases there is “tribal wisdom” or the excuse that if the Framistan hasn’t failed in 350 hours it must be done right. Perhaps, but there are some notable examples of certificated aircraft where a rigorous process didn’t uncover a particular fault until years or decades later. Is that evidence of negligence?

I’ve had the honor of meeting with Dick VanGrunsven and you won’t find anyone more concerned about design, safety, pilot proficiency, judgment, ease of kit assembly, and the use of proven methods. There are thousands of Vans kits flying and he’s become one of the most successful manufacturers in the world.

But building and maintaining an aircraft is still a daunting task. The certificated manufacturers have to regularly defend against a variety of suits—most of which are groundless but very expensive. The “gotcha approach” once a suit is filed doesn’t always serve the industry or buyers of aircraft particularly well. An admission that something could be improved, such as more guidance or improving the hardware, is often used as evidence of wrongdoing when that isn’t usually the case.

This trial will be closely watched from many quarters. In the interim let’s insure that our machines are so well built (if we built them) and maintained that we’re willing to put our families into them. Don’t forget that flying part either.

Staying Alive in a Two Dimensional World

Winter is coming, so I thought it a good time to touch on an optical illusion called flat light. Though it is more prevalent during winter months, it can occur any time of year.

For VFR flight, we need to see enough of the ground as a reference to control the aircraft and to avoid terrain, which is the problem with this illusion. Those of us who fly in Arctic regions take flat light very seriously, but it can also occur at lower latitudes.

If you haven’t experienced it personally, flat light can be difficult to appreciate. While horizontal visibility may often be very good–like being able to see a mountain range 50 miles away–when looking down one is unable to focus on the ground.  Imagine being able to see the ground, without having the depth perception necessary to determine exactly how far away it really is. In a flat light condition your height above the ground determination may be off by as much as 2,000 feet!

The problem stems from the limitations of how we perceive our world. Our brain acts as a video processor and models an image based on raw data received from the retina via the optical nerve. We only see .0035 percent of the electromagnetic spectrum, visible light in the near ultraviolet class, and that data is badly pixilated with a hole in it. The hole, commonly referred to as the blind spot, is due to a lack of light receptors where the optic nerve attaches to the retina. Even when we close one eye we don’t see the blind spot because our brain is very good at interpolating data. It simply fills in the picture with what it calculates should be there. An interesting experiment demonstrating the brain’s imaging capability is when people are fitted with special glasses, turning the images they see upside down. After a time, the brain makes the correction and everything is right side up.  That is until the glasses are taken off, when the image once again goes upside down until the brain can once again adapt.

If that wasn’t problematic enough, the best part of our field of view with good resolution is very narrow. Based around the retina center, it is about 1 degree, or about an inch using the distance from the pilot to the aircraft instrument panel. Now you know why our instructors always stressed a proper scan! As humans, we are stuck with these sensory capabilities, which unfortunately don’t serve well flying in a flat light environment.

Flat light typically occurs during winter with overcast skies and a snow-covered ground. The combination of a very reflective white surface and a lack of direct sunlight turns our 3-dimensional world into one that looks 2-dimensional. There are no shadows or contrast, which are necessary for depth perception. Rock, trees, rivers, buildings, and roads can all provide the pilot with a much needed depth reference. Knowing this, a prudent pilot flying over a large flat white valley may opt to fly along an area with objects providing contrast, such as a rocky ridgeline.

One of the things that makes flat light so dangerous is its insidious nature. The pilot thinks he can see the ground and judge the altitude. Others may be convinced that if it’s daytime and there isn’t a ground obscuration, such as fog or blowing snow that they will be able to see the ground well enough to avoid crashing into it.

 

Loss of direct sunlight due to an overcast cloud layer over flat terrain covered with snow results in ideal conditions for flat light.

Losing sunlight over flat terrain covered with snow is an ideal conditions for flat light.

The closer one is to the ground the more dangerous the situation, as during takeoffs and landings.  You may have just landed on snow covered terrain with the sun shining, only to find 15 minutes later the sun has dipped below a ridge or been covered by a passing cloud.  You are now enveloped in a shadow of flat light where an attempted takeoff could be very dangerous. This is a case where you are better off being on the ground wishing you were in the air, rather than being in the air wishing you were on the ground.

There was an incident in 1999, when a company crashed three helicopters in one day and all on the same glacier due to flat light. The first helicopter encountered flat light on the glacier and experienced a hard landing, injuring the pilot and passengers. With the first aircraft overdue, a second helicopter was dispatched to search, which also crashed on the same ice field. A third helicopter began to search for the two missing aircraft, which also ended up crashing on the same glacier. The pilot of the third helicopter reported that he thought he was 500 feet above the ground when the aircraft impacted the ground.

These were experienced pilots who had been flying tours over this glacier day after day. They didn’t become less experienced in a day and the glacier didn’t change. What changed were the lighting conditions. It can be hard to accept that at times one can see the ground without enough depth perception to know how far below it really is. Without instrumentation such as a radar altimeter or TAWS (terrain avoidance warning system), the pilot won’t even realize it’s happening.

Anywhere, anytime

Vermilion Bay, on the shores of Louisiana, is so notorious with Gulf of Mexico helicopter pilots that it is commonly referred to as “Vertigo Bay.” The bay’s water has a reddish brown color, and when coupled with an overcast cloud layer, low visibility, and no wind it presents a significant hazard to VFR flight. It is the same effect you get in a room with a full-sized wall mirror when it gives the illusion of the room being much bigger than it really is. Vertigo Bay is so large that with visibility less than 5 miles you can’t see land, and without any wind the highly reflective mirror-like water provides no contrast, but instead reflects the cloud layer from above. When these adverse conditions exist, VFR helicopter pilots circumnavigate the bay sticking close to the contrast of the shoreline.

 

Highly reflective mirror-like water will reflect the cloud layer from above, making it difficult for the pilot to judge the height visually.  This is the Beaufort Sea north of Alaska, and though the water is reflecting the cloud layer from above, the sandbars, ship and distant ice pack help provide contrast for the pilot.

Highly reflective mirror-like water will reflect the cloud layer from above, making it difficult for the pilot to judge the height visually. This is the Beaufort Sea north of Alaska, and although the water is reflecting the cloud layer from above, the sandbars, ship and distant ice pack help provide contrast.

Avoidance is the certainly the best remedy for flat light. Understanding the environmental conditions where flat light can exist helps the pilot in early recognition and avoidance. Study the terrain along the planned route of flight, including possible areas where you may divert. Review weather reports and forecasts to determine what lighting conditions will exist on the flight. Avoid flying over large expanses of water without wind to ripple the surface and direct sunlight to provide contrast. Stay clear of takeoffs or landings or any low-level flight over large areas of white snow without some direct sunlight. Flat light is a condition where a conservative approach is best, using your superior judgment to avoid the necessity of using your superior skill.

(These views and opinions are my own and do not necessarily reflect the views of Era.)

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