June 18, 2013
When a gain on one side requires a loss on the other, we call that a zero-sum game, and in aviation, that’s frequently what happens in the name of increasing capacity. Many people simply assume we’ll go faster and farther, carry more and cost less – because that’s the way it’s always been. But if you look closely at the aviation world, you find areas where capacity grows only by cramming more things of smaller size into the same space.
Most notoriously, that’s the way the game is played with airline seats. Seat “pitch” is the term the industry uses for the space between rows of seats, another way of defining legroom, albeit indirectly. It’s changing all the time, but the typical pitch in economy is now about 31 inches, down from 34 or more, with Spirit Airlines coming in at a shin-scraping 29 inches. Spirit, not so coincidentally, is the discount carrier that pioneered the idea of non-reclining seats. Meanwhile, all airlines will tell you that seat padding has gotten thinner, but hasn’t sacrificed any comfort because of modern cushioning materials, hence the closer spacing between rows.
Asian airlines tend to really cram people in, perhaps because the average person there is not as bulky as the rotund Westerners with their trendy obesity. Passengers gripe constantly about seat pitch, especially on long flights, but the only way for really large people — tall or wide — to find comfort is to buy it. If you dig deep into your wallet, and pay for business class and higher, the knee room goes up by as much as a foot. The seats not only recline, they’re wider and — again for a price — lie flat like a bed for long-distance flights.
Another area that’s feeling the squeeze is radio communications, and, in particular, the air band, which spans frequencies from 108 to 137 MHz. The radio spectrum is like real estate — they’re not making any more of it. In the beginning, voice communication radios had 70 channels spaced 200 kHz apart from 118 to 132 MHz, with the lower bands from 108 up to just below 118 dedicated to navigation channels. As voice traffic grew, they split the channels in half, with 100 kHz between them. In the 1950s, they did it again, down to 50 kHz, and then, as the industry boomed in the 1970s, to 25 kHz, providing 720 channels. Now the Europeans have taken to splitting each channel into three parts, with 8.33 kHz spacing. Some radios in the U.S. offer that option as well, mostly for use at high altitude. This splitting and re-splitting has been a boon for the people who make the radios, because they’ve had successive waves of obsolescence to drive buyers. It gets a little bit more expensive to improve the selectivity of a radio so that the receiver can accept only the frequency it’s tuned to, but channel splitting has been the only way to increase capacity in the air band since day one.
Now a lot of voice communication is expected to be replaced by digital text messages, which should eliminate errors and the problems of congestion that typify a busy push period at a major terminal when everybody is trying to talk at once. (You can hear the radio chatter during crazy hour at JFK here).
The ultimate scarce commodity in the aviation business is airspace, although the fact that it’s three-dimensional makes air traffic density a different problem from highway congestion. The choke points show up near major airports, and not so much in the en route airspace. All those arriving flights have to funnel into a runway or two, which means air traffic controllers have to work at sequencing the arrivals so they have enough space between them to allow for no-panic landings and their wakes don’t toss around the following aircraft. Very large aircraft attach the word “heavy” to their call signs as a reminder to Air Traffic Control that they require a larger trailing interval.
Until recently, human skill and experience provided the ideal interval between aircraft, but now computers and ultra-precision navigation promise to narrow that interval to, perhaps, the limits imposed by trailing wakes. In other words, airplanes will arrive in sequences and at intervals that are much closer than they are now. Will that alone eliminate delays in arrivals and departures? No. Only the construction of more runways near the busiest cities can do that. London is struggling with the problem right now, and may end up locating new runways far from downtown.
Capacity comes dear. And it’s wise to remember that when we gain something, something else usually has to give.
March 27, 2013
On March 22, an FAA press release announced the agency’s decision to close 149 control towers following the cutoff of funding more commonly known as “sequestration.” Outgoing transportation secretary Ray LaHood said the selection of towers for closing — all of them operating under contract — involved “tough decisions.” But in the aftermath of the announcement, there’s been little information about what effect the closings will have on flight operations.
Airports that have operating towers are designated as “controlled” fields. Those without towers are, simply, “uncontrolled fields.” Typically these are small rural airports, but they range in size from a single runway to former military bases with miles of paving.
FAA employees staff most airports that serve airlines and the traveling public, and those will remain open, although some may close at night when traffic tends to decline. The towers targeted for closing are staffed by non-federal controllers who work for private companies under contract to the FAA. In some cases, airports or local governments fund all or part of such a tower’s operation, and these towers too should be relatively unaffected.
How much of an effect will the closures have? Pilots of all stripes already follow established procedures for flying into uncontrolled fields. These procedures are spelled out in the Aeronautical Information Manual (formerly the Airman’s Information Manual) and are usually learned in the first few days of flight training, when the student pilot practices pattern flying and landings. If a tower is closed, inbound pilots would still tune in the tower frequency, transmit their position and intention to land, then follow that with continuing updates of position in the landing pattern; example: “States Air 43 is downwind for runway two-two, Metro Regional [Airport].”
At uncontrolled fields, pilots use a designated frequency — commonly called “Unicom” — to transmit advisories and monitor other nearby flights. An FAA spokesperson confirms that these established procedures will continue unchanged if the tower closures proceed with the first phase on April 7; the third and final phase is in May. Many airports are equipped with automatic weather monitoring and repeating transmissions that give pilots current conditions, and some also allow a pilot to illuminate the runway lights by keying the radio mike a set number of times.
Flight service facilities known as fixed base operators at some small airports voluntarily monitor Unicom and may even reply to incoming pilots with information about other aircraft known to be in the area. There are no plans to expand this service to actually control a field with a closed tower, however, probably due to questions about liability.
To sum up, the traveling public and operators of general aviation aircraft should notice little impact if the closures take effect. Pilots value the additional level of safety that tower controllers provide, but most will exercise additional caution and make good use of their radios.
March 5, 2013
Engineers who work in aviation learn to be risk averse. Change tends to happen slowly, through evolution rather than sudden breakthroughs. When a new idea comes along, it’s usually tested for years before being introduced to the fleet, and even then it usually debuts with the military—they have ejection seats, after all. Some engine components are tried out in ground-based turbines for electrical power plants before working their way into aircraft engines, a practice GE says it pursued for its latest engines.
One maxim of jet engine design is that higher power comes at a cost of greater heat. Unfortunately, heat melts metal. So anyone who can make an engine run hotter and still survive will be able to tweak more thrust out of the same amount of fuel. People have been working at the problem for years.
Early in the game, engineers tried alloys that could survive the 2,000+-degree-Fahrenheit gas that meets the first set of turbine blades. But the gas, coming straight from the combustor, put such stress on the turbines that they only lasted tens of hours. The metal would soften to a point where the rapidly spinning blades elongated, and their tips began to rub against the tip seals on the engine’s outer wall.
By combining metals such as nickel, chromium and even more exotic elements from the periodic table, engines could be made to run hotter and survive. Later, the blades were made from crystals grown in such a way that the metal’s grain aligned with the centrifugal force, lending greater strength. Another improvement was cooling the blades with tiny passages that carried cold air to the leading edge, using air from the engine’s compressor to supply the cooling flow. That stole some power from the compressor, but the investment paid off in higher combustion temperatures and improved power and efficiency.
Research into the use of ceramics in the engine’s hot section began decades ago, starting with ceramic coatings on combustors and parts of the turbine section. A NASA technical memorandum (89868) dated May 1987, authored by Gerald Knip, Jr. at NASA’s Lewis Research Center in Cleveland, Ohio, describes “revolutionary materials” applied to subsonic jet engines. It describes ceramic composites that overcome the typical brittle quality of ceramics by using reinforcing fibers in much the same way that carbon fiber reinforces modern composites.
GE and the Air Force are now going all in with advanced ceramics, which are incorporated into a research engine called ADVENT for ADaptive Versatile ENgine Technology. In tests, the engine is reported to have run hotter than any engine ever built. Ceramic matrix composites, or “CMCs,” made from silicon carbide matrix and fibers, make it possible for the engine to tolerate gas temperatures of 2,400 degrees and achieve a reported gain in fuel efficiency of 25 percent. With fuel prices so high, that kind of progress, following decades of materials research, couldn’t come at a better time.
January 23, 2013
The Boeing’s 787′s problems with onboard lithium-ion batteries led to the FAA’s decision to ground the fleet. That’s hardly surprising. But some erroneous information has found its way into public forums concerning the nature of these high-tech but somewhat touchy batteries.
To begin with, the kind of battery used on the 787 is rechargeable, which makes it different from the small lithium batteries sold in AA sizes at the hardware store. Those get used up and thrown away. The 787′s rechargeables also are different from the lead-acid batteries commonly used to provide start power for automobiles. About 20 years ago, it was common to add water to lead-acid batteries when the quantity of electrolyte, a dilution of sulfuric acid, dropped too low. Today the batteries are sealed and vented.
Lithium undergoes a spontaneous chemical reaction in the presence of water, which is one reason water is not a component in its electrolyte. The electrolyte is not an acid, nor is it corrosive. The liquid used in lithium-ion batteries is made up of organic chemicals — more specifically, hydrocarbons. The greatest risk, therefore, is that the electrolyte might ignite and burn; despite some news stories to the contrary, corrosion is not a concern.
The battery also relies on an ultra-thin plastic membrane perforated by tiny openings to allow ion migration between the positive and negative poles. Maintaining battery integrity relies heavily on the precision manufacture of that component and others, as well as on the quality of materials used in fabrication. One potential weakness of lithium-ion batteries is a kind of thermal runaway in which voltages get too high and create high temperatures in one cell, which can break down and affect adjacent cells, causing a destructive cascade.
The current investigation appears to be narrowing to the manufacture of the batteries and of the battery charging systems that control rate of charge, and thereby ensure safe operation. Meanwhile, because Airbus reportedly plans to use lithium-ion batteries on its new A350 family of airliners, it is following developments closely.
January 15, 2013
The people who manage airline companies are torn between two opposing ideas, both driven by cost concerns: having the very latest technologies in their aircraft, on the one hand, and sticking with the time-tested and proven on the other. If you don’t think airlines are a capital-heavy industry, just take a look at what’s parked on the ramp at any terminal airport. Even at a smaller regional airport, the airplanes and hardware have a total value in the millions. And that’s where the cost concerns come from. It takes a steady stream of revenue from passenger and freight operations to service the debt on all that stuff.
When fares were regulated, the numbers were stable and predictable, but deregulation arrived in 1978. Before that, airlines marketed mainly on their images as reliable or glamorous — or even hip (Braniff’s “the end of the plain plane”). With competition, the only marketing tool an airline had was the price of a ticket, and fares fell. Throughout the 80s, 90s — and even into the new century — major airline companies collapsed by the dozens, leaving merged giants that dominated in certain regions to survive.
Price competition will inevitably drive cost cutting, and airlines have turned to the suppliers of their aircraft for help. The manufacturers have to attack not the list price of the aircraft but the life-cycle cost of the airplane’s operation, which will total many times its purchase price by the time it is retired from service.
So when Boeing’s 787 Dreamliner makes headlines because of an equipment bay fire, as it has recently, it should hardly be surprising. In order to produce an airplane that would save its customers on the order of 20 percent in cost of operation, the company had to turn to completely new technologies in materials, propulsion and electronics. When you promise that kind of savings to a customer, you do one thing: you reduce the airplane’s weight. Which helps to explain why the 787 has a completely new type of battery that uses lithium instead of lead and acid or nickel-cadmium in an electrochemical closed system that produces a direct-current voltage. The battery is lighter, and it’s the same type that invaded the laptop computer market for the same reason — and occasionally with the same result: Sony made some laptop batteries back in 2006 that overheated and had to be recalled. There’s little difference between what happened to some unlucky laptops and what occurred in the battery of a 787 parked at Boston.
Airlines and their suppliers expect some birthing problems when any new type enters service. If there are new technologies aboard, those problems are almost guaranteed. The Boeing 747 had new large-fan engines, and after some time in service, their internal housings distorted from perfect circles to ovals, causing catastrophic wear. For a time, Pan Am’s global fleet carried spare engines in pods that were added near the fuselages of the jumbos. The airborne “pool” of replacements minimized the schedule delays when an airliner went out of service.
The introduction of so many new technologies at once in the 787 is almost unprecedented, and prospective passengers can take comfort in the fact that the problems have everyone’s attention. After all, these changes have the ultimate goal of keeping the price of a ticket low.
November 2, 2012
People in the airplane sales business try to dress for success, same as anyone. But the formula has changed over the years. Back in the days of multibillion-dollar airliner deals involving Boeing, Douglas, Lockheed, Convair and others — before deregulation, during the golden age of air-travel glamour — the costume was hand-tailored business suit, preferably a nice dark blue pinstripe, and wingtips (those are shoes, for those who’ve never seen a pair–you can Google them). A rule of thumb in those days was that the price of a really top-quality suit closely tracked the market price of an ounce of gold.
The folks who sell to airlines haven’t changed clothes, even though the airline business is almost unrecognizable compared to what it was back in its heyday. At Paris and Farnborough, the boys from Boeing and Airbus are still wrapped in Saville Row as they schmooze clients. At the next level down — high-priced executive jets and even mid- to economy-priced GA airplanes — fashion has changed markedly since the ‘70s. Back then, a general aviation salesman from Wichita, Kansas who hoped to make an impression might dip a toe in the water of mod styling. You could spot the guy from the marketing department a mile off by the glare from his white patent leather belt and matching shoes. Hairstyles matched the longer, coiffed look of the times, with fuller sideburns and more exuberant cuts that draped just over the ears. Trousers were flared but not bell-bottom, and contrasting sport coats were a light color or bold pattern, with a pocket hankie to match the primary-color trousers. (Some “looks” should stay in the era from which they came. The leisure suit should not, by law, be allowed to survive except in museum collections and photos of the quaint old 1970s. It is the swastika of men’s fashion.)
That was kind of fun and adequate for selling airplanes with propellers to doctors and oilmen. But when the GA factories started building jets, the sales department went straight for that Wall Street look – the full Corporate Uniform.
Now we’re undergoing yet another, more subtle shift. Blame it on Silicon Valley, where nobody ever wears a tie knotted four-in-hand, but the business-jet crowd is showing the first signs of shedding the banker look. In some recent advertisements, manufacturers (of airplanes with a price so high one must not speak its name) are depicting their executives tieless. The big issue becomes whether to leave just one shirt button open, or go radical and liberate two [music from Born Free here]. If the Google guys and that Facebook billionaire can run around in tee shirts aboard their Boeings, surely airplane people – who are just as high-tech as you are, dammit!! – can drop the ties.
But don’t lose the dark navy-blue blazers. Please. That would be going too far.
October 12, 2012
Airplanes that look beautiful from the outside only reward their owners as they’re strolling up to board it. But time spent inside the cabin lasts far longer, and leaves a more indelible impression.
With that bit of wisdom in mind, the HA-420 Hondajet has been designed not to showcase a sleek exterior, but to afford the most spacious cabin possible in a light business jet. Now the American Institute of Aeronautics and Astronautics has named Hondajet designer Michimasa Fujino as the winner of its 2012 Aircraft Design Award.
The first unique feature that smacks the new Hondajet owner in the eye is the engine location: It’s mounted on struts that extend from the upper surface of the wing – the very place where, as Fujino likes to recall, he was taught in engineering school you never place the engines.
The next eye-grabber is the forward fuselage and nose section, which bulge like a swollen gland. They’re configured that way to encourage smoother airflow and reduce drag, despite the off-putting squid-like appearance.
Once inside, the benefit of the engine location becomes apparent in the startling spaciousness of the cabin, which extends farther aft than it does in traditional twinjets, where the engines are mounted behind the fuselage. There’s also room for a huge baggage compartment. By mounting the engines on the wing, all the plumbing that usually fills the aft fuselage moves elsewhere, freeing up space.
Fujino-san, as he’s known to his employees at the company’s Greensboro, North Carolina headquarters, deserves the award for supreme patience and persistence, if nothing else. But then, Honda has always been a patient and persistent company. And it’s said that founder Soichiro Honda had always been interested in aircraft.
The little jet began as a design study in the 1980s, then as a flying proof of concept aircraft – the MH02 – built under the aegis of Mississippi State University’s aeronautics division. The prototype for the HA-420 first flew in December 2003, nearly 10 years ago. And it’s been Fujino’s baby from day one.
Some would argue that it’s strange to give the award to an airplane design that has yet to prove commercially successful. The Hondajet has so far sold only about 100 orders (Honda is vague on the numbers). Not to mention that the airplane has yet to receive its FAA certificate of airworthiness. When the Eclipse Very Light Jet won the Collier Trophy back in 2005, there was a muffled outcry from its competitors because its status in the market was ambiguous, and the company went under soon afterward (it has since been revived).
But the Honda situation is different. The company speaks in terms of transportation, not vehicles. It is focused on movement, not machines. Its laboratories are as likely to experiment with four-legged robot walking machines and the locomotion of insects as it is with engine emissions – an area which it happens to have pioneered. The company even launched its own small jet engine, the HF120, which has led to a partnership with General Electric’s aero engine division.
Fujino deserves this award for pursuing successfully the engine-over-wing configuration that has proven itself in testing. After all, the 420 in the aircraft’s designation is derived from its top speed in knots. That’s 483 mph, fastest in its class.
So congratulations to the man who inspired a new airplane, a new way to mount the engines on light twinjets, and a company – one with staying power – that’s brand new to aviation.
April 27, 2012
Back in the 70s, regional airlines began to play a significant role in the national transportation system by flying people from large hubs to small-town airports in rural America. The aircraft of choice was a twin turboprop of modest size, such as the Beech 99 or the Twin Otter, a bush airplane made by de Havilland Canada. Soon Embraer in Brazil was turning out the EMB 110 Bandeirante, and the “bandit,” as many called it, made serious inroads into the market. Many of those first-generation aircraft are still operating in other parts of the world, but not so much in North America.
Those were 19-seat airplanes, typically. But the industry was growing fast, and it began to look at 30-seaters. At the same time, some operators had detected an aversion among the flying public to airplanes with propellers. The turboprops were loud and not as fast as jets, and people would get one look at a twin turboprop parked at their gate and whine louder than the airplane’s engines. It was time to move on to regional jets.
For a regional jet to make economic sense, it has to provide a speed advantage so that the operator can fly more revenue legs on a given day than a turboprop would. If the price of fuel is manageable–and this is the key–the additional fuel consumption of the jet will be at least partly offset by an added couple of money-making trips.
It looks as if we may now be switching from a period where jets served the regional markets to a time when those jets will be parked and the turboprops will come back. Manufacturers like the French-Italian consortium ATR and de Havilland Canada have built turboprop airplanes with more seats and higher cruise speeds. The ATR 72-500, for example, delivers speeds well in excess of 300 mph. When flown on trips of, say, 300 miles, a jet is only a few minutes faster, but burns half again as much fuel. Fuel cost is affecting all airline operators, but the regionals are far more sensitive to operating cost. At the same time, engineers have learned how to cancel the vibrations generated by the propeller tips on the turboprop engine.
In a recent analysis published by AirInsight, a Baltimore, Maryland consulting firm, the company notes that one of the first regional airlines to reconsider its fleet makeup is the largest in the United States—SkyWest. The company has over 300 airplanes in its fleet. Says AirInsight, “The airline has to consider its 159 50-seat regional jets obsolete (given current economics)…We anticipate SkyWest will use a mix of high-speed turboprops and larger [regional jets] as it rationalizes its fleet.”
There are skeptics who believe that oil prices can’t remain high forever. Maybe not, but every time the economic news is favorable, oil seems to rise. With developing nations’ growing energy needs, global prosperity means expensive oil. Regionals can’t hedge fuel with the clout of the major carriers, one of which, Delta, is even in the bidding to acquire a shuttered Conoco-Phillips refinery in Philadelphia. As AirInsight concludes, “Absent a new and more fuel efficient 50-seat regional jet and continued high fuel prices, the future success of the high-speed turboprop appears inevitable.”
April 6, 2012
The economy may be recovering, but business aviation, which always lags recoveries, is still in the doldrums. Aircraft factories are operating at a fraction of capacity, and thousands of pilots, maintenance technicians, dispatchers and managers have been laid off.
The biggest risk during an extended layoff is that your currency— how recently you’ve practiced your profession—may lapse, which can make it nearly impossible to get re-hired. Some pilots and techs pick up contract work— part-time freelance jobs—but for those who can’t find anything, life can be grim.
One of the leading training companies, Flight Safety International, just announced an extension of a program to provide people who have trained with them in the past a chance to keep up their proficiency if they’ve been laid off. It’s not the first time FSI has done this; back in 2009 and ’10 they introduced the offer, “So this actually represents an extension of what we did back then,” says company spokesman Steve Phillips.
He credits company CEO Bruce Whitman with the original idea. “Bruce wanted us to come up with a way to help these people out, and this is the result,” Phillips says. The program is open to those have been “involuntarily unemployed since January 1, 2012,” according to a release. Pilots of business aircraft under a training contract with FSI at the time of layoff get no-cost training in whatever type aircraft they were training for.
Maintenance technicians who were enrolled in FSI’s Master Technician program at the time of involuntary job loss also receive the next course to completion for free. Pilots and technicians are not required to repay for the cost of the training.
Phillips says there’s no tax deduction for FSI, and although there will be some costs to the company, “The costs will be managed,” he says. “People in the program will be added to classes that are already scheduled, but yes, there is a cost for simulators and manuals and the like.”