 | | | | | |||||||||||||
| |||||||||||||||||
           Government Weather Flight Planning Tools General Aircraft Magazines Books & Tapes Organizations 
|
|
October 2008 
Maximizing Aircraft EfficiencyAre you getting the most performance from your airplane? The fact is a considerable amount of unused performance gets overlooked by the average owner/operator. Both performance and range can be improved through common operational techniques, performing regular maintenance procedures and careful planning. Most of this "hidden performance" can be gained back from wasted fuel and increases in the airplane’s useful range. In turn, you can reduce the annual operating costs. And with average aviation fuel prices nudging $6 a gallon in the U.S., who wouldn’t want to enhance their airplane’s efficiency? Thankfully, it’s not as complicated as it may seem. You just need to make the machinery work the way it was designed to work. One method is to ensure the airplane is as mechanically sound as it can be. Then, we’ll look at improving its basic aerodynamics, followed by some smarter flight planning. Finally, we’ll look at ways to save fuel while airborne. When Flying Birds Collide with Your Aircraft As we practice our license to learn, some hazards demand our frequent attention: Traffic, weather and terrain are the top three. They present varying levels of predictability, and a huge amount of brain power and economic investment has been poured into keeping pilots out of the teeth of these hazards. But what about the less predictable living hazards that share the airport—and sky—with us? Plenty of critters live on and around airports, and as for sharing the sky with birds, well, they got there first. Sometime in the 1980s, a Japan Airlines-bound ab initio student at Napa Airport, Calif., (APC) had a rough time understanding the tower controller’s by-the-book NOTAM. She warned, "Aircraft in the vicinity, be aware of large waterborne fowl in and around the airport environment." After several futile rounds of the hapless student pilot requesting that she say again, she finally bellowed, "Birds! We have birds on the runway!" Birds in the aviating environment are far from the cute critters alighting on Cinderella’s hand. A brown pelican, for instance, can pack a punch, weighing up to six pounds (and let’s hope you never encounter the 33-pound Dalmatian pelican). Turkey vultures weigh up to 10 pounds; however, the mass generated by a closure rate greater than your en route cruising speed can be incredibly destructive. Size doesn’t always matter: The tiny starling is a feathered bullet, with a body 27 percent more dense than the herring gull. Causes of Hypoxia and Flying Non-Pressurized Aircraft at Lower Altitudes Twelve thousand five hundred feet. Fourteen thousand. Fifteen thousand feet. If you’re a pilot, you immediately recognize the significance of these altitudes. Each triggers different requirements for supplemental oxygen use. Most of us learn the FARs associated with these requirements early in our primary training so we can spout them back on written exams and in the oral portion of the Practical Tests. After that, we may never think much more about them. But like most FARs, the oxygen rules are a minimum standard of safety. Of what real-world relevance are the oxygen requirements of FAR 91.211? From the standpoint of safety, when should you be using supplemental oxygen? Supplemental oxygen, for those not familiar with the term, is additional oxygen added to ambient air. The goal is to provide enough "added air" to bring the O2 user’s oxygen intake up to the same level it would be at a target altitude (usually sea level). The need for additional oxygen increases with altitude, since (obviously) the higher you go, the more O2 you have to add to give the breather sea-level air. For example, one aircraft manufacturer’s automatically regulated oxygen system meters supplemental air at the rate of 0.5 liters/minute/person at 5000 feet, scaling up to 2.8 liters/minute/person at Flight Level 250. Aircraft Takeoffs and Landing on Shorter Runways Early on in my flying career, taking off automatically meant, absolutely free, one mandatory dead-stick landing. That’s because I was flying hang gliders and developed an easy appreciation for fitting into small spaces. Later, after someone thought to put a small engine and propeller on one and dub the results an ultralight, my well-honed, dead-stick landing skills proved handy too frequently. Thankfully, the engines used on ultralights in those early days have improved greatly but—like a catchy tune you just can’t shake after hearing it on the radio—I still think in terms of whether a nearby field is large enough for landing. Coincidentally and for the same reasons, short-field takeoff skills with an ultralight received equal attention. After all, once you "land out" in an ultralight and resolve whatever caused the engine to fail, you still need to get back to the car. Best of all, the better our short-field skills, the more options we had for operating, powerplant status aside. Once I moved up to flying larger, heavier, faster airplanes, those same instincts came with me, as did the comfort of knowing I had the ability to safely operate from fields that might make a knowledgeable passenger utter an audible, "Whoa…." Pilot and Air Traffic Controller Communication When you think about it, the IFR system is really a wondrous thing. For example, every airport, navaid, fix and procedure has certain basic characteristics shared by all other similar facilities. For another example, a unique name or identifier is assigned, helping eliminate confusion between ATC and pilots. To navigate from one to another, the operator requests a route, naming the various facilities to be used. A flight plan is filed, or a radio request is made, a controller compares the request to his or her needs and a clearance is issued. On one level, it’s a simple system. On another, it’s incredibly complex. So complex, in fact, errors are found every day by pilots and controllers, and then corrected. The result is a relatively safe and efficient national airspace system. One of the keys to making it all work, however, is pilots and controllers cross-checking each other’s work. Most of the time, no errors are found. Sometimes, though, someone forgets something, or the system proves too inflexible. In those situations, operators and ATC sit down to figure out what went wrong and develop procedures to consider each other’s needs. This is my tale of finding an omission in the system, and how little effort it took for a fix to be implemented. Flying Your Aircraft Above It's Gross Weight I regularly fly my airplane some 250 pounds overgross. But, I do it legally, since it’s equipped with an STC’d tip tank installation. The STC (supplemental type certificate) allows operation at a maximum gross takeoff weight of 3550 pounds, an increase of around 7.5 percent from the airplane’s original 3300-pound gross weight when it left the factory. But there’s no paperwork accompanying the admittedly older STC providing performance charts at the higher gross weight. There’s no question performance suffers at the higher weight, but I’m legally allowed to use the older, lighter weight in computing performance. To compensate, I make sure I use runways of adequate length when operating at the higher weight and higher-than-published airspeeds, accepting a lower climb rate. The tradeoff is worth it. Whether by placing too much aboard, or putting it in the wrong place, loading an airplane outside its weight and balance envelope is relatively easy to do with most GA aircraft. It’s one thing to know you’re slightly over the gross weight and have the runway to handle it. It’s quite another to overload the airplane and then fail to consider the impact on performance.
|
About Us / Contact Us / Privacy Policy / Site Map | Copyright Belvoir Media Group, LLC. All rights reserved. | |||||||||||||
