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The Gross Weight (Empty weight) of an X-15 is 14,600 lb.
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∙ 11y ago
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Why does glide ratio not change with aircraft weight?
"Who said it doesn't? Of course it changes. The Lift force has to equal the weight of the aircraft. The amount of lift generated is a function of airspeed and angle of attack. Lift does not increase just because the aircraft weighs more. So, if two aircraft are identical other than weight, the lighter one glides further."Incorrect ! Absolutely wrong!Glide ratio (L over D or L/D) is NOT affected by aircraft weight. The glide ratio is a factor of the physical form of the aircraft; the drag produced by the aircraft shape & profile and the lift produced by the wings.Those factors do not change and we are speaking of aircraft best glide ratio, so, by definition, while producing the least drag which means landing gear retracted & flaps up, referred to as "clean".Aircraft manuals (POH- pilot operating handbook) that list glide ratio & often the speed at which to fly to achieve best glide ratio (greatest distance the aircraft will fly) always refer to aircraft maximum gross weight. If the aircraft weighs less, the best glide speed will be lower.A rule of thumb; for every 10% (1%) below gross weight, reduce speed by 5% (.5%) to achieve best glide speed.A Cessna 172 empty weight is about 69% of maximum gross weight. W/ min. fuel and 150lb pilot the plane weighs about 76% of gross, so 24% less weight = 12% reduction in speed to arrive at best glide, reducing best glide from 65 kts at gross weight to 57kts at minimal weight.This can be significant and determine if the plane reaches the planned touchdown point.Conclusion is, a heavier aircraft will glide the same distance as a lighter aircraft (of identical make/model) but it will need to be flown at a higher speed to do so.Yes, the lift produced is a function of airspeed & angle of attackas best glide ratio is a function of angle of attack (AoA). So a specific AoA must be achieved to insure best glide / longest distance over the ground.The most perceived difference between lighter and heavier aircraft is, the heavier aircraft arrives in the same spot, faster.The same effects are in play with air density and higher altitude.Air is thinner, less lift and less drag, but Lift over Drag (L/D) is still a factor of the physical structure, shape/ profile and the lift produced by the wings.This does not change when the air is thinner.I do not have information as to how to adjust the speed for best glide ratioas altitude increases and air density decreases.It is amazing how many pilots and aviation professionals do not understand this.
How many aircraft does NASA have?
Zero aircraft
Why cannot aircraft fly in space?
An aircraft is designed to fly in 'air' there is no 'air' in space.
What new invention detected aircraft?
In the 1940s the new invention of radar detected German aircraft off the coast of England.
What is the first aircraft in space?
sputnik I
What is the square root of x15?
It is √(x15), which can be simplified to approx 3.873*√x.
What does the weight of the airplane have to do with the lift of it?
The weight of an aircraft counteracts the lift produced by an aircraft. The heavier an aircraft weighs the greater the lift needed to get off the ground.
What is 12-x15 is?
-3
What is the lift force in an aircraft?
The lift force is the force acting against the aircraft's weight. For straight and level flight, lift acts in the upward vertical direction and the weight of the aircraft acts in the downward vertical direction. For level flight, lift = weight.
What is the same as x to the power of 15 divided by x to the power of -3?
18
Why empty weight is needed in aircraft?
It's not so much "needed" as it is a physical consequence. The empty weight is the weight of the aircraft itself - without fuel, crew, passengers, cargo or weapons.
What is the weight of an F14 aircraft?
Gross weight (Empty weight) of the F-14 is 43,735 lb.
What is 1557 miles into hours by air?
It depends on what you are flying in. A combat aircraft (X15) could take a little over 20 minutes. A Concorde (when it was flying) would take just over 2 hours. An ordinary passenger aircraft would take nearer 3 hours and then there are many smaller slower planes.
What is operating weight of an aircraft?
dry operating weight + take off fuel
What does 100.93 x15 equals?
the answer is 6.72866666 recurring
What is the weight limit for sports aircraft?
600 kg for aircraft operated from land, 650 kg for seaplanes.
What is the importants of thrust to weight ratio in aircraft?
It is important because it is essential for for climbing of aircraft. There is a limit for thrust to weight ratio. When an airplane exceeds it, it cannot climb effeciently.
