The problem could be solved, in part, by fast commercial airliners that can fly more passengers to their destinations in less time. Right now, the faster you fly the more fuel you burn. Last year, the longest non-stop flight in commercial aviation history took 19 hours from Singapore to Newark, New Jersey. At the same time, the aviation industry has never been more aware of the importance of reducing its carbon footprint, especially in light of recent climate change events.
The challenge of flying faster, on less fuel, has spurred several projects researching the use of new composite materials and sustainable fuels in airline travel. The research is set to solve the problem of fuel efficiency in super-fast aircraft.
The British Aerospace , BAe for short, is a short-haul regional airliner. The BAe features a large airbrake with two petals at the rear of the fuselage below the tail rudder instead of thrust reversers. The advantage of the airbrake over thrust reversers is that they can be used during flight and allow for steep descents if needed. The BAe had a cruise speed of Mach 0.
One of the notable features of this aircraft, and its engines, is that it had a very low level of operational noise. This was because of the geared turbofan ALF — the gearbox allows the fan speed to stay below the speed of sound, which greatly reduces the noise emitted from the engines. Having equipped four engines on the BAe meant that it had superior takeoff performance on short runways and in hot and high-altitude conditions. This aircraft was the second-ever short-haul jetliner to enter service, following the French Sud Aviation Caravelle.
The One-Eleven was designed and built to replace the turboprop Vickers Viscount on short-haul routes, though it proved to be quite popular with domestic airlines and various international operators.
It is one of the most successful British designed airliners. The BAC had a cruise speed of Mach 0. Compared to its predecessor iterations of the One-Eleven, the Series was longer by 8ft 4in ahead of the wing and 5ft 2in behind the wing and Rolls Royce Spey turbofan engines.
The aircraft also featured a modified cockpit that incorporated avionics systems and instrumentation which included a more sophisticated autoflight system. An aircraft surpassing the speed of sound generates a shock wave that produces a loud booming sound as it passes overhead; fine, perhaps, over the Atlantic Ocean, but many countries banned supersonic flights over their land. Some hope for future supersonic travel remains, at least for those able to afford private aircraft.
Several companies are currently developing supersonic business jets. For now, it seems, travelers will have to appreciate the virtues of high-bypass engines, and perhaps bring along a good book. Log in to post comments. Marcelo Pacheco. Actually, a very large part of higher turbofan efficiency is due to higher combustion temperatures, a result of better materials that can withstand higher temperatures and far more precise control over airflow inside the combustion chamber that reduces heating of the combustion chamber wall.
Since those improvements are invisible, they're often ignored. The first twin engine wide body cruises at Mach 0. The other often ignored aspect of airliner cruising speed is the variability of Mach speed vs temperature and altitude. All of those aircraft could cruise some 10 knots faster, by burning more fuel, but airlines nowadays like to cruise strictly at the lowest cost index a little slower. A and A normal cruise is Mach 0. There were not only Concorde supersonic civil aircraft, but also Tupolev Tu Phil Cassady.
The "sound barrier" is the problem. Even when using Bluebook aircraft values as comparisons, which are usually low, it shows that airplanes like the Bonanza, which are much larger and more luxurious, but nowhere nearly as efficient as the Mooneys, command higher prices. So why do people buy Bonanzas over Mooneys?
Please note that the pricing figures were estimates. Times have changed, and so have prices. How far will it go without making a fuel stop? Suddenly, fuel capacity becomes a really big deal. So, to safely make 1, miles and still have some reserve, it would have to stop twice to get gas. The actual time in the air would be 5.
Two fuel stops, however, are going to add 1. For a trip of 1, miles, the Bellanca looks good again. But that second fuel stop on a really long mission is a killer.
Mooney Acclaim Ultra. Courtesy of Mooney. Still, back to that hypothetical 1, trip. So, it easily can make it with only one stop. Seven and a half hours of flying, plus 0. So, the much faster Bellanca Viking only got there 55 minutes faster. But are all of those things a really big deal on such a long trip? And in general, airlines are reducing flight speeds to conserve fuel.
In , the airlines made news in a bad way when the U. Air cargo is a tiny percentage of daily flights around the world, meaning passenger planes are still responsible for the vast majority of these emissions.
Some general cost-cutting measures could save fuel as a secondary effect, like overselling flights in order to fly fewer, but fuller, airplanes each day. In some countries, the culture is beginning to move away from flying when possible, but globally, the middle class with access to tourism continues to grow at a rapid speed.
Airlines have worked to cut emissions by making more efficient aircraft, researching alternative fuels, and investing extensively in carbon offsets. But as with cars and other vehicles, planes have optimum cruising speeds that are the most efficient for fuel, and this is usually slower than impatient travelers have grown to expect.
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