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for fuel at our Dekalb Taylor Municipal Airport (KDKB) FBO location in Dekalb, IL (123 nm to OSH).
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DFW Fudging ATC Operational Error Rates?
GA Boosters Back Airlines In FAA Reauthorization Talks
AVweb At EAA AirVentureIf you can't make it to EAA AirVenture in Oshkosh, Wis., next week, then you'll be happy to know that AVweb will bring the show to your desktop. We'll be publishing daily issues, podcasts and video posted directly from the show grounds to keep you up-to-date with the latest news from AirVenture. And for those lucky enough to be going to the airshow, don't forget to stop by AVweb's booth to enter to win one of several ExxonMobil fuel cards or even our grand prize: upset recovery training from APS Emergency Maneuver Training. |
The U.S. Office of Special Counsel (OSC) late last week directed DOT Secretary Mary Peters to investigate allegations by air traffic
controllers at Dallas/Fort Worth International Airport that management has covered up ATC operational errors at the facility. According to the OSC, air traffic controller Anne Whiteman told the
special counsel in 2004 that managers at the DFW TRACON routinely covered up operational errors by not properly investigating and reporting them as required by FAA policy. Making it even worse,
Whiteman said she was reprimanded by her managers and harassed by coworkers because of the disclosure. In February 2005, the DOT Inspector General reported that her whistleblowing had resulted in the
exposure of a seven-year management practice of underreporting operational errors. The report noted that FAA officials considered the underreporting to be very serious and had begun corrective
actions. In recent disclosures made by Whiteman and an unidentified whistleblower alleged that FAA personnel at DFW are routinely identifying operational errors as pilot errors. The FAA maintains that
all controller errors are being correctly reported and said its inspectors recently visited the airport. In some cases, the whistleblowers say that managers have improperly interpreted FAA orders and
directives to cover up operational errors. "We had been led to believe that her disclosures and the inspector general's final report had taken care of the problem," said U.S. Special Counsel Scott
Bloch. "Instead, matters got worse, and we believe the trend to blame pilots for what are really errors by air traffic controllers resulted from a push by FAA top management to reduce the number of
operational errors." He noted that the whistleblowers disclosures reflect a problem that could be national in scope.
Sen. John Rockefeller, D-W. Va., said he’s determined to ensure general aviation pays more to support the modernization of
the air traffic control system. During hearings on the reauthorization of the FAA by the Senate Finance Committee, Rockefeller threatened to restrict GA access to congested airspace if user fees are
not imposed on this segment as part of the reauthorization package. He said airline passengers should not be forced to "continue to subsidize corporate jets." It should be noted that this is the same
congressman who’s worked hard to attract business jet manufacturer Sino Swearingen and the now-defunct Tiger Aircraft to his home turf of Martinsburg, W. Va. In fact, as he lobbies for fees that
corporate aviation groups say will hurt their industry, he’s also actively involved in a rescue of Sino Swearingen, whose major investor -- the Taiwanese government -- is now trying to get out of
the deal. Rockefeller told local media last week there’s someone waiting in the wings to buy the Taiwanese shares. Assisting Rockefeller in the battle for user fees is Sen. Trent Lott, R-Miss.,
who is apparently thought of well enough by the aviation community in Pascagoula, Miss., since they named the local airport after him. Trent Lott International Airport specializes in handling
corporate airplane traffic, according to its
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Canadian User Fees Drop Four Percent
Investigators Say Student Pilots Should Be Flagged
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As the debate heats up in Washington, D.C., over the imposition of user fees for general aviation aircraft, Canada's nonprofit,
privatized air services provider Nav Canada has announced that the fees it charges will go down 4 percent across the board for at least a year. For the owner of a piston single, that means the annual
fee will drop from $71 to $69. The overall annual revenue reduction to the company will be about $50 million. Nav Canada says cost control and an increase in air traffic combined for the rosy
financial picture that allowed the reduction. And conspicuously included in the 
Britain’s Air Accidents Investigation Branch (AAIB)
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Two Weeks To Taxi Offers RV Help
Ohio Aircraft Repair Shops Hurt By Sales Tax
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The popular Two Weeks To Taxi builder-assist program started by Glasair to help sell its Sportsman 2+2 homebuilts has now
evolved into a standalone business and is expanding its service. The company will now allow those purchasing Vans RV-7 and RV-10 aircraft the opportunity to build their kits in about 14 days under the
guidance and organizational direction of licensed mechanics and expert aircraft builders in a facility designed and equipped expressly for the purpose. Company officials say the expanded service
should help more kits get built. "Between the two companies (Glasair and Vans), more than 14,000 aircraft kits have been sold, yet many remain unfinished," Michael Via, president of Two Weeks To Taxi,
said in a news release. "We feel that providing a service focused on allowing builders to complete an aircraft in just two weeks is a remarkable opportunity." [more] The two-week program (it can take
a little longer in some cases) has been operating for three years, and Via said those who have done it swear by it. He maintains that the program not only assures the project will get done, it
solidifies costs and almost certainly results in a better airplane. The program complies with the FAA’s 51-percent rule, and the company is now taking reservations for those who will be getting
their RV kits in early 2008.
Aircraft repair businesses in Ohio are lobbying the state to repeal a sales tax on parts and labor they say is causing layoffs and
threatening businesses. According to the
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Fossett Claims Gliding Speed Record
Fellow Passengers Sue TB Patient
Venezuela Drafts Law To Shoot Down Unidentified Aircraft
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Aviation record collector Steve Fossett and New Zealand soaring expert Terry Delore have set a speed record for gliding over a
1,250-km (675 nm) triangular course. Fossett and Delore averaged 149.23 kmh (80.56 knots) over the course from Ely, Nev., last week. Delore told Christchurch’s The Press newspaper that even
though it wasn’t a “ripper” of a day in the skies over Nevada, they still got the job done. “…We were able to maintain a good and steady pace, even in the absence of cloud for
a good chunk of the flight," Delore said. "After 27 attempts and 18,000 km [9,719 nm] of desert flying, the longest-standing world speed record is ours, subject to ratification. We are rapt." In
contrast to most of their flights together, Delore said he did more flying on the record flight while Fossett concentrated on navigation and looking for favorable conditions. Delore said they
didn’t set out to break the record that day. They intended to test new equipment on the ASH-25 (25 is for the 25-meter wingspan) sailplane. The old record of 143.46 kmh (77.46 knots) was held by
German Hans Werner Grosse since 1987.
Seven Canadians and two Czechs have launched a $1.3 million lawsuit against an Atlanta lawyer for his "reckless" behavior in boarding a
flight knowing he had tuberculosis. "He deliberately got on this plane, endangered our lives and this is very selfish and reckless behavior that deserves to be punished," Nassim Tabri, a 26-year-old
graduate student who was sitting one row ahead of Andrew Speaker, told the 
Straying into Venezuelan airspace could soon have dire consequences.
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Buried Wreckage Investigated
Aircraft Fuselages Become Library
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Construction workers digging a water line trench near Watsonville, Calif., last week unearthed a chunk of riveted metal, some bullet
casings dated 1942 and part of a burned parachute. And now the town is buzzing about what might be buried there. Various local authorities, along with officials from Travis Air Force Base, are now
examining the contents of the hole to see what it is and if it’s safe to bring it into the light of day. "There's definitely a piece of history there, whatever it is," Kenny Lazzerini, who owns
the strawberry farm on which the wreckage was found, told the 
They’ve been turned into homes, restaurants and businesses, but a New York firm has found a more scholarly use for
discarded aircraft fuselages. LOT-EK, which is described as "urban architect recyclers," has designed a library in Guadalajara, Mexico, made entirely out of the aluminum tubes. Now it’s not clear
whether the books are stored in the seatbacks or whether the overhead storage compartments come into play, but LOT-EK says the fuselages make a good building. "The fuselage becomes the basic module of
this building. It is insulated and furnished according to the program. The internal subdivision generated by the existing floor joists is used to respond to functional needs,"
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On The FlyThe FAA is investigating a runway incursion at Fort Lauderdale (Fla.) Airport in which a Delta Airlines airplane had to go around to avoid a United airliner that had taken a wrong turn onto the active runway. The FAA credited sharp-eyed controllers with avoiding the accident…The FAA is proposing an airworthiness directive on Trimble or FreeFlight Systems 2101 I/O Approach Plus global positioning system (GPS) navigation systems. A software upgrade is needed to stop annunciation errors… A DC-10 air tanker will return to service next week after wing repairs. The aircraft clipped trees after hitting a downdraft while working a fire in California on June 25… In the funny books, a four-color Bristol Fighter biplane-inspired hero named Danger Aceis one of the leading contenders in Dimestore Productions' Small Press Idol contest. (Think American Idol for comic books.) The comic that sells the most copies this week will win a four-issue publishing deal.
AVweb's Newstips Address ...
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The Pilot's Lounge #115: The Loneliness of a Town Without An AirportIf a town of decent size doesn't have an airport, what other sparks of life doesn't it have? Click here to read Rick Durden's column. I saw a couple of farms and ranches that boasted a hangar and a lovingly-tended airstrip. Each was so inviting it was all I could do not to land and see if there might be some home-made ice cream to be had. "Hi, I'm here. I'll trade you a ride in the biplane for some ice cream." I wonder if it would work? About 90 minutes into the second leg of the trip -- about the time the seat was feeling less and less comfortable and the question of "What in the world am I doing here?" was starting make itself known -- I saw what looked to me to be one of the most delightful villages I had ever viewed from the air. In an area of gently rolling hills, the community was built on a ridgetop, providing commanding views in all directions. Had there been a castle and walled ramparts in the center, I don't think I would have been surprised. It was a lovely setting. The town was so striking that I made a gentle circle around it, savoring the view over the side of the cockpit coaming and wondering what it would be like to live in such a picturesque spot. There was a two-lane highway serving the town and I estimated that there might be maybe 8000 or 10,000 residents. A river wide enough for excellent canoeing or kayaking curled along the base of the ridge. Stone ruins along the river looked to have once been a flour mill. On such a nice weekend day, I expected to see folks tubing and canoeing on the river, walking beside it or riding bicycles throughout the town. I was more than a little surprised to see no one outside, despite a plethora of cars moving about. Good grief, what sort of people live here? Are they not aware of what they have? Does no one in this town enjoy the simple pleasure of being outdoors on a beautiful day? I looked at my sectional to spot the nearest airport. I was in no hurry; this town was worth exploring even if the citizenry were oblivious to the world around them. There was bound to be a café where I could sit outside and have lunch and maybe a used book store where I could part with some cash. In fact, if there were a decent bed and breakfast, I'd be returning here with my wife to spend a weekend. From where I sat, the place looked charming. I searched the sectional in vain. The town had no airport. There was no airport nearby; the closest was probably 35 or 40 miles away by road. I was aghast. What foolishness reigns here? There are dozens of perfects sites for runways within a mile or so of town. What sort of community of this size is so short-sighted as to not have an airport? Does no one in this town dream? Does no one in this town wonder what is beyond the horizon? Does no one have any sense of adventure? No wonder no one was outdoors.
Economic Advantages of Airports[IMGCAP(3)] Rolling out of my turn I flew on southwest. Yet, for the rest of the day, through two more fuel stops, I was unable to get what I had seen out of my mind. By and large, in this country, if a town has at more than 4000 people and is more than a 45-minute drive from an airport served by airlines, then the town is probably going to have a community airport. I felt the long-ago degree in economics start turning the gears inside my skull and I began thinking of airports in terms of money and jobs for small communities. From a cold, hard, economic sense, virtually no such community can attract any sort of major employer if it doesn't have very easy access to an airport. The ability to rapidly move people and things has been a basic tenant of successful business since the Second World War. Take the state that is the watchword for middle America, Iowa. It is not a state that one tends to equate with big business; it is rural and intensely agricultural, so most business has been tied in with supporting farming, and is therefore local. After the war, the state made sure that virtually every community that had an airport had the money to pave at least one runway and install at least a non-directional beacon so that every airport had an instrument approach. (Those airports now have GPS approaches.) It turned out that farmers and the businesses catering to them did need to move parts, documents and people fast in order to be successful. The farsightedness of the state in supporting small town airports paid off. One of the basic ways of tracking community health in Iowa is to look at the small towns that have airports and those that do not. The ones without airports have been steadily losing population over the last three decades. (In all states, small-town "brain drain" is a serious concern, as only the lower quarter of the high-school graduating classes seem to remain in town.) However, at least in Iowa, in a time when the small community is dreadfully at risk, the ones with airports are holding their own, not losing population. The airport means that the local small-business owner or farmer can get that part or document quickly when time is truly of the essence. It means being able to have the freedom to live and work away from the crushing foolishness of a city but still get to those cities quickly when it is necessary. After all, no matter what business a person is in, when the work is all over, the only thing left is time. And that local airport means extra time and the chance to live and work where a person desires. I couldn't help but think about Iowa City, Iowa. It is home to one of the finest universities in the nation, the University of Iowa. It has one of the oldest continually operating airports west of the Mississippi River. It was one of the few original stops on the very first transcontinental air mail route. When the mail began to be carried by civilian contractors rather than just the Postal Service, those contractors became airlines and started carrying passengers. Iowa City was front and center in the growth of the airline industry; its citizens had only to drive to the south edge of town to board the very newest and finest United Airlines could offer on its service across the country. An hour's drive away, the smaller town of Cedar Rapids sat in the shadows, just another community. It was doing OK because it had an airport, but not as well as Iowa City with its airline service and University attracting businesses. In the 1950s United Airlines approached the Iowa City leaders asking that the runways at the airport be lengthened so their new generation airliners could continue to serve the city. In one of the great foolish moves of all time, the city said no. Cedar Rapids fell all over itself to expand its airport. In a relatively short time, the airlines that served Iowa City all moved out and went to Cedar Rapids. Over the last half century the results have been quite startling; Iowa City has carried on as a very pleasant university town. Cedar Rapids is now larger, and has attracted the high-tech businesses one might have expected to go to the university community. What is fascinating to me is that Iowa City leaders are regularly competing with their friends in Cedar Rapids to attract businesses that will help their tax base, yet they cannot seem to understand why they are at a disadvantage and often lose out. They try to make light of the 45-minute drive to the airline airport and cannot seem to understand that they blew it years ago. Time is extremely valuable and a business choosing between two attractive communities, one with an airline airport and one without, is going to pick the former. class="copy"> Livable Cities Have Airports[IMGCAP(4)] As I thought more about that very pretty town without an airport, I found that my thoughts moved away from the chilly economic analysis to the whole idea of what makes a place livable and attractive. I thought about the people who live in that town. What do the kids who do when they dream -- as all kids do -- of far horizons, of the big world out beyond the corn and wheat fields on the edge of town? What sort of support do they get for their dreams? What reinforcement do they have that they can make their dreams happen someday? They rarely get to see a little airplane in the sky overhead on its way to who knows where. They don't get to bicycle out to the airport and look at those little airplanes and see people they know flying them or think that those airplanes are of the size they might fly. They don't get to wonder where a little airplane might be going and what they might see and do if they were flying it. The airliners flying by are so high that they are unheard, leaving -- at most -- a brief-lived contrail in the heavens. Is that silent contrail enough to pull the eyes and dreams of a child or a teenager skyward and outward from everyday existence? Is there anything in that town to pull the kids away from the televisions and computer games and alleyway drug sales that are now so sadly prevalent in our smaller towns? Is the contrail enough to inspire dreams of greatness, of reaching for more in life? Where does the kid who wants to be inspired go? How does that kid ride a bicycle to the airport fence and look at the runway or the windsock and dream of bigger things?
No Airport = No FutureI could not help but be saddened by the stultifying loneliness a young man or woman must feel to be stuck in a town that does not show any sign of looking outward by having something so simple as an airport runway, that time-honored symbol of a gateway to adventure. Are the kids there easy prey for the beaten-down adults who tell them to quit dreaming, to quit being "foolish" and be content with what they have been given and their lot in life? Are those kids easier prey for the dealer who tells them that this here meth will take them away from this crummy town? How can the people of a town be so insular, so close-minded and content with the mundane, as to not have the most basic of airports? My thoughts returned to my initial desire to visit the town, and I wondered whether I would enjoy the people I might meet who had proclaimed to all who cared to see that they were content and attuned to just beetling across the surface of life rather than living it fully. Would there be anyone there with any sense of creativity, of adventure, of fascination with ideas beyond the horizon? Would they be a town of risk avoiders, insurance salespeople, belt-and-suspenders wearers whose idea of a fabulous time was to go to the local bar and get blotto while watching professional wrestling on the television? As I flew into the evening, I concluded that it was a very pretty town. Yet I suspected the people of a town without an airport might well possess other bad habits that are not so immediately observable. Life is short enough that I'm not willing to risk a visit to find out. After all, I'm not going have time to get to see all the places I know for certain I want to see. Nevertheless, I will feel sorry for the residents of the town without an airport, especially the kids. They know not what they are missing. See you next month.
Want to read more from Rick Durden? Check out the rest of his columns.
Propeller Governor DiagnosticsWhen your prop surges, hunts or does anything unusual, do you know what to check first? Click here to read this maintenance article. pressure decreases blade angle), it's the low-pitch stop that will occasionally get set improperly. This will show up as the inability to reach proper static-RPM because the blades can't go to a low enough angle to allow the engine to spin up to max. RPM. Once you're rolling on takeoff, however, the RPM comes up, and for the rest of the flight everything is just fine. A note of caution here: On the single or twin, this particular problem will only happen after prop-hub maintenance of some kind. A similar symptom showing up suddenly or gradually, with no maintenance having been done on the prop or engine, indicates a weakening engine or possible governor-system trouble.
Piston Stick[IMGCAP(5)] The piston in the prop dome can stick occasionally. It usually happens when a seal gets pinched between the piston and cylinder wall. Sometimes, an engine that has experienced metal contamination will have metal particles wedge between the piston and wall, as well as tear up the seal. The centrifugal force in the prop dome slings debris right into this area and will eventually cause problems. That's why the prop is one of the components on the list of things that must be disassembled or overhauled after a metal-contamination incident to eliminate debris. To check the twin for a sticky prop, start the engine and wait for the governor to bring the blades off the feather locks, usually indicated by a slight rise in RPM a few seconds after the oil pressure starts to come off zero. At about 1,000 RPM, bring the prop to feather and immediately shut down the engine. The prop will stop fairly quickly, enabling you to watch it go into feather. There should be a smooth, constant movement to feather that only stops at the feather stop. If the prop requires help to fully feather or is jerky or sticky in its movements, you should get it sent out for repair. To check the single for a sticky prop, see the section below on transfer-system troubleshooting. A worsening problem is indicative of hydraulic lock or excessive clearance in the oil-transfer system. First, let's look at hydraulic lock.
Hydraulic LockHydraulic lock is pretty unusual. It will act similarly to improper low-pitch-stop settings. On single-engine aircraft, the prop will not bring the engine RPM down as low as it should. The engine will also speed up with an increase in airspeed or an increase in manifold pressure (engine torque). On a twin-engine prop, it's just the opposite: The engine won't go to correct static RPM any more. On the twin this could also indicate a bad transfer system, so you'd better troubleshoot for both. The oil-filled McCauley propeller is the most likely to fall prey to hydraulic lock because it is designed to trap the red-dyed oil in the hub and retain it there. The other McCauley models are vented through a small hole in one of the hub-mount dowels, making them less likely to lock up. If oil is coming out that dowel hole, you have the same leak by the prop piston seals that could lock up a Hartzell. Hartzell hubs have no vent and, therefore, can be susceptible to hydraulic lock, however unusual it may be. To check for this condition in a Hartzell, set the hub with a grease zerk pointing down and remove the zerk. If oil comes out, you're getting oil past the piston (single) or piston-rod seal (twin) in the hub. The oil may also blow out the blade-shank seals (grease seals) and make a mess of the cowl and nacelle. On the Hartzell twin props, if the front-side piston seal is going bad, the air charge in the dome usually leaks out into the oil cavity and is vented back to the engine during prop cycling. A continuously low prop dome will cause other problems discussed later. A proper piston/dome reseal will cure this problem in either make propeller.
Oil-Transfer System[IMGCAP(4)] The oil-transfer system is the only other cause of this RPM control problem. This includes the governor and oil-transfer components. The governor may have a bad internal leak in the pump, pilot valve or pressure-relief valve. Any of these will cause the governor to lose some or all control. There is no direct troubleshooting for this unless you have a governor bench handy. The problem must be found by process of elimination. Since the governor has to be pulled off to send in, first check out the transfer system. Oil is transferred in from the prop governor to the prop through one of the below-mentioned methods. If there is excessive leakage in this transfer system, the prop won't be able to hit high-pitch/low-RPM on the single, or low-pitch/high-RPM on the twin. The twin may even go into an uncommanded feather. This is because too much oil is leaking from the excessive clearance of the transfer system. This problem can come from several sources. On the system with bearing transfer, either a standard bearing on an undersized crank or bearing galling causes the clearance to increase and thereby leak oil. On the transfer-collar system, the transfer collar will be too large for the crankshaft, either because of galling or improper fit. On the transfer-tube type, the tube-end clearance will be too large for the same two reasons as excessive transfer-collar clearance. To check for this problem, the prop governor must be removed. Use shop air and an air gun with the rubber tip inserted into the prop transfer hole in the governor pad. Put full shop pressure on this transfer hole until all the oil is blown out of the main bearing (no gurgling is heard). When you start this you should notice the prop blades go to immediate high-pitch setting on singles or against the low-pitch stop on most twin-engine governors. If you want to kill two birds, you can just pull the prop governor and do this check, seeing if the blades go to high pitch, checking for hydraulic lock, sticky blades, and blowing all the oil out of the bearing at the same time. You'll have to do this two or three times so that the oil will be removed from the prop dome. Caution: Do not pull the rubber tip out of the hole until all the pressure inside the prop dome is released. If you do, you will be covered with a huge spray of oil. Also note it should only take about 30 to 40 psi for the prop to go to its pitch stop. Now hook up a compression tester to the shop air hose and the rubber-tipped air gun to the compression tester instead of a cylinder fitting. Set the compression-tester regulator to 80 psi, as you would for cylinders. With the rubber tip held up in free air, activate the air gun. Make sure that the source gauge reads 80 psi and that the cylinder-side gauge reads zero, with all air escaping from the air gun. Now, put the air-gun rubber tip back in the oil-transfer hole and fully activate it. The only air leakage should be a small amount from the transfer point. Set the compression tester to 80 psi and read the cylinder-side gauge. On a Lycoming, the pressure held by the main bearing should be between four and 20 psi. The low figure here is a little hard to see sometimes, especially with some gauges starting at 10 or so. One reason a Lycoming transfer system can go so low is the engine operating oil pressure. They run between 60 and 90 psi, which aids in lessening the oil leakage from the transfer region in the center of the front main bearing. A Continental should be no less than 40 for the engines with transfer collars. For the Continental engines with the transfer in the main bearing, the cylinder-side gauge should be no lower than 18 psi. If the cylinder-side gauge falls out of these specs (on the low side), then the transfer system is bad and the engine must be disassembled. If this is not the problem, the governor should be sent off for a thorough bench check.
Governor Malfunctions[IMGCAP(3)] There are a few problems caused by the governor that we should talk about next. The flyweight toes can sometimes wear a flat spot in the on-speed condition position, causing the governor to lose sensitivity and do some RPM "seeking." A worn pilot-valve bearing can also cause the governor to "seek" or maybe even surge. A badly worn pilot valve will leak too much oil and act like a bad engine-transfer system, as can a bad governor oil pump or its associated relief valve. The transfer system check will narrow this to the governor or the engine.
Other FactorsA few factors to also consider are the peculiarities of some models of props. The Hartzell used on the Aztec and some twin Comanches relies on just the air-charge in the prop, the ATM (aerodynamic twisting moment) and the internal spring to counteract or balance the governor pressure. There are no counterweights. If the dome air charge is low, the RPM will be airspeed sensitive; that is, the RPM will increase with airspeed and decrease with airspeed. This is true of most Hartzells but especially of this particular model because of the lack of counterweights. Hartzell also changed the air pressure in the domes of most of their other piston propellers (see Hartzell Service Bulletins 111D, 112, 114D, and 115D). These Service Bulletins add a feather-assist spring in the air-charge side of the dome and lower the air-charge pressure accordingly. In these props the dome pressure is now down around 40 psi, whereas before it was around 70. If you put 70 psi in a prop that has had this Service Bulletin accomplished, you may have trouble with props going into feather at low idle-speed and hot oil. Like a leaky transfer system, this will generally show up on landing rollout.
Prop SynchronizationSometimes prop-sync systems on twins will give some similar symptoms. If the system is mechanical and doesn't park the governor control in the right spot, you may not be able to get maximum RPM (parks too low) or feather (parks the lever too high). Be sure the system parks in the center position. Some older Cessna systems, with the driver motor on the governor control arm, can continue to run and cause the RPM to fluctuate constantly. The cause is the park micro switch doesn't activate and the motor runs continuously. Pulling the prop-sync circuit breaker will stop this fluctuation if it's the problem.
Control RiggingCheck control rigging before tearing into the system too deeply. The governor arm should hit its high-end stop and the arm should not be excessively loose on the speeder screw shaft. The control cable mounting should be solid and mounted to the engine, not the airframe. Sometimes a piece of baffling can move with air loads and interfere with the governor control arm (especially Continentals, due to the forward low-governor position). Engine movement, due to torque, thrust or worn engine mounts, can also cause control-cable movement when the control-cable mounting is loose.
System HealthThere isn't much that will affect the governor control system, but the things that do can cause expensive repairs if you don't watch it. Keep the oil changed regularly -- as we always recommend. Oil contaminated with moisture will corrode the aluminum parts in the propeller and cause prop piston-seal leakage. High oil temps (consistently at or near redline) can cause transfer-collar-equipped Continentals to wear the collar more than normal, causing eventual loss of RPM control. A great help in case of oil contamination from some sort of debris is the governor gasket with screens in the "smile" (intake port of the governor). The screen can catch particles that would otherwise cause scoring or galling in the governor and transfer system. They can save you from replacing a lot of governor parts in case of metal contamination. The transfer collar in the Continental is especially vulnerable to this problem when it occurs. The clearance on the collar/crankshaft is less than two-thousandths of an inch and the tolerances are measured in 10-thousandths of an inch. Galling or scoring in this system can easily result in a crankshaft needing to be reground or even failing inspection altogether, meaning you'll be buying another one. This is a huge expense best avoided with a little care. Just about every system in an engine benefits tremendously from clean oil. Additional propeller information may be found at the manufacturer Web sites: Hartzell Propeller and McCauley.
More aircraft repair and prevention articles are available in AVweb's Maintenance Index. And for monthly articles about aircraft maintenance, subscribe to AVweb's sister publication, Light Plane Maintenance. |
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AVweb Audio NewsAVweb posts audio news on Mondays, plus a new in-depth interview each Friday. In last Friday's podcast, you'll hear you'll hear David
Billings on the enduring allure of the Amelia Earhart mystery. And AVweb's podcast index includes interviews with BusinessJetSEATS Alfred Rapetti; EAA's Dick
Knapinski; AOPA's Andrew Cebula; Cirrus Design's Alan Klapmeier; NBAA's Harry Houkes; Reason Foundation's Robert Poole; SATSair's Sheldon Early; Epic Aircraft's Rick Schrameck; AOPA's Randy Kenagy;
Eclipse Aviation's Vern Raburn; Xwind's Brad Whitsitt; BoGo Light's Mark Bent; DayJet's Ed Iacobucci; Pogo Jet's Cameron Burr; Teal Group's Richard Aboulafia; Air Journey's Thierry Pouille; Epic
Aircraft's Rick Schrameck; Cessna's Jack Pelton; Embraer's Ernest Edwards and LAMA's Dan Johnson. In Monday's podcast, Aerion vice
chairman Brian Barents talks about his company's supersonic business jet design. Remember: In AVweb's podcasts, you'll hear things you won't find anywhere else. |
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| FBO Of The Week | back to top | |
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FBO Of The Week: Elliott Aviation
Nominate an FBO | Rules | Tips | Questions | Winning FBOs
AVweb's "FBO of the Week" ribbon goes to Elliott Aviation at KMLI in Moline, Ill.
AVweb reader Jim Grady likes how they treat the "liitle guy." "Our Sunday evening arrival was literally as the staff was out the door and off duty. They returned, parked us, took the fuel order and even took us to town in the van. All this was for a couple in a little taildragger, not a jet-A customer!"
Keep those nominations coming. For complete contest rules, click here. AVweb is actively seeking out the best FBOs in the country and another one, submitted by you, will be spotlighted here next Monday! |
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| Video Of The Week | back to top | |
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Video of the Week: Near Mid-Air Collision with Big ConsequencesRecommend a Video | VOTW Archive
Shifting our attention back to safety this week, we have a video clip from YouTube user RemosG3. The near mid-air collision here ends with actual mid-air when the Rans S6 (with camera aboard) strikes the tow line attached to the glider the Rans barely missed. The line isn't clearly visible, so watch closely — and if you listen closely, you can hear the line hit the Rans and the parachute deploy.
Don't forget to send us links to any interesting videos you find out there. (Try as we might, we can't seem to goof off enough to see all the videos on the Web!) If you're impressed by it, there's a good chance other AVweb readers will be too. And if we use a video you recommend on AVweb, we'll send out an official AVweb baseball cap as a "thank you." |
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| The Lighter Side Of Flight | back to top | |
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Short Final
We were leaving Martha’s Vineyard when my student nervously contacted Cape Approach: Cessna 38W: Cape Approach, Cessna Three Eight Whiskey, student pilot departing the Vineyard, requesting advisories to New Bedford. Cape Approach: Cessna Three Eight Whiskey, Cape Approach. This should be interesting. I’m a student controller, squawk 2234, and ident. |
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| Names Behind The News | back to top | |
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Meet the AVwebFlash Team
AVwebFlash is a twice-weekly summary of the latest news, articles, products, features, and events featured on AVweb, the internet's aviation magazine and news service.
Today's issue was written by Contributing Editor Russ Niles (bio) and Editor In Chief Chad Trautvetter.
Click here to send a letter to the editor. (Please let us know if your letter is not intended for publication.)
Comments or questions about the news should be sent here.
Have a product or service to advertise on AVweb? A question on marketing? Send it to AVweb's sales team.
If you're having trouble reading this newsletter in its HTML-rich format (or if you'd prefer a lighter, simpler format for your PDA or handheld device), there's also a text-only version of AVwebFlash. For complete instructions on making the switch, click here.
Aviate, navigate, communicate.
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