We compare the performance of aircraft in an unnatural world. A laboratory, really. When you read that this or that aircraft flies so many miles at this or that speed, the information is likely accurate, but may not be achievable in the real world. The problem is not by design but by default.
In order to have a benchmark to measure against, the industry calculates aircraft speed, range and fuel burn in a perfect mythical atmosphere where there is no wind and the air temperature is always right at the international standard. But of course, the real atmosphere doesn’t behave that way. There is always wind slowing your trip as a headwind, or blowing you along faster as a tailwind. And air temperature, which has enormous impact on a jet’s performance, is always changing.
In the artificial laboratory where aircraft performance comparisons are calculated, air traffic controllers always assign pilots the perfect altitude for the weight of the aircraft and the length of the trip. And in the lab, controllers always agree to the direct route to the destination without deviation and instantly approve every altitude or course change request. Talk about a fantasy world. Just ask any pilot.
In the midrange performance specification contest the Gulfstream G280 leads in every category—that cannot be denied. It has the longest range at 3,600 nautical miles/6,667 kilometers. The G280 normal cruise speed of Mach 0.80 is the fastest. It climbs directly to 43,000 feet/13,106 meters after a maximum weight takeoff in 21 minutes, putting it on top of its competitors. And passengers enjoy the largest, most comfortable cabin while the engines burn the least amount of fuel per mile flown—up to 12 percent less fuel than any other aircraft in its class.
Nonetheless, Gulfstream’s technology gives G280 pilots more tools and more capability to deal with the imperfect real world we all fly in. Perhaps the most important Gulfstream G280 technology advance is the wing. Similar to the wings on other Gulfstream models, the advanced G280 wing creates very high lift so the aircraft climbs quickly to high altitudes, but the wing also keeps drag low when the aircraft is flying faster than its competitors, which adds speed and range and improves fuel economy.
Because the G280 can climb directly to 43,000 feet/13,106 meters, pilots are likely to be cleared to high flight levels above the routes crowded with lower flying airline jets and other less capable business aircraft. And the sooner an aircraft reaches higher altitudes, the sooner you begin realizing the benefits of fuel economy in thinner air at cruise speed versus climb.
Flying above 40,000 feet /12,192 meters improves fuel-efficiency markedly, makes direct routing by air traffic control more available, puts you above nearly all turbulence and weather issues, and most often reduces the impact of headwinds. The density of air decreases with altitude so at typical G280 levels a headwind will usually be less than for lower flying jets.
The fast Mach 0.80 normal cruise speed of the G280 is another capability that helps in the real world of flying. Any aircraft loses range that is proportional to its cruise speed when flying into a headwind. The headwind represents a smaller proportion of the airspeed of a fast aircraft so a smaller percentage of speed and range are lost to the headwind. With the fastest in class cruise speed, the G280 range advantage over other midrange jets increases when pilots encounter the inevitable headwind.
The superior wing technology and the thrust reserve of the G280’s Honeywell HTF7250G engines also give pilots tools to deal with above average temperatures at cruise altitudes.
It’s always cold outside at jet altitudes but often not as cold as normal. Pilots call those conditions “above standard temperature” and only a few degrees of air temperature increase make a big difference in how an aircraft performs. When it’s warmer aloft, the air becomes less dense causing the engines to lose thrust and the wing produces less lift.
Gulfstream’s technology gives G280 pilots more tools and more capability to deal with the imperfect real world we all fly in.
The advanced wing technology of the G280 delivers a significant lift reserve when flying at high altitudes, which is important for safety if unexpected turbulence is encountered, and for maintaining cruise range when air temperatures are warmer. Other jets with less capable wings are forced down to lower cruise altitudes by warm temperatures.
The G280 engines also have a reserve. The engines are limited to 7,624 pounds of thrust for takeoff, but are capable of producing much more power. That means this “flat rating” of capability is held in reserve to deliver rated power when the air temperature goes up. The G280 maintains its cruise speed and fuel-efficiency when Mother Nature doesn’t conform to the perfect world of performance specifications.
Among the other real world performance advantages of the G280 is its PlaneView280 cockpit. Gulfstream was the first business jet manufacturer to deliver primary electronic flight displays and has continuously advanced avionics capabilities in the many years since. The high-speed computers at the heart of the PlaneView system analyze the real conditions of wind, temperature and routing to show pilots how to optimize speed, range and efficiency. The many variables are too complex for even the most experienced pilots to analyze precisely, but PlaneView continuously shows G280 pilots how the flight is progressing and suggests available options of altitude and routing for greatest speed and efficiency.
All aircraft are fast with a tailwind and when pilots get optimum altitudes and the air temperatures are normal. But the G280 has large margins designed to complete trips when conditions are less than ideal. Giving pilots—and their passengers—more options to fly fast and far is what the G280 was designed to do better on paper. And in the real imperfect world of winds, weather and air traffic the G280 goes even faster and farther than other midrange jets. After all, it’s a Gulfstream.
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