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A turboprop aircraft, such as a Cessna, cannot fly as fast as a turbofan aircraft, such as a Boeing. Because of this, lift cannot be maintained at high altitudes. As you go higher, you can go faster because there's less air to slow you down. But if you don't go fast enough, then the plane will stall and keep falling until it reaches an altitude at which lift can be maintained at its current speed.
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What type of engine does a B52 have?
The B-52H has eight Pratt & Whitney TF33-P-3 turbofan engines, each providing more than 17,000lb of thrust.
What altitude turboprop engine can fly?
That depends on a few things. How big is the plane, how many engines does it have, how many blades on each propeller, etc. More blades will let the aircraft keep moving forward and maintain lift at higher altitudes where the pressure is low, but if speed isn't the problem, then the question is if the engine can get enough oxygen to keep the engine running. If the pressure is too low, then the engine will stall and shut down. Restarting the engine again after having fallen to a lower altitude ought to work. As for the average ceiling, I'd say no higher than 40,000 feet if you can get that high, probably 30,000 feet would be the ordinary limit.
What is the speed of fan in a turbofan engine?
Most turbofan engines have parts running at more than one speed. The inner most compressor stages and the first turbine stages usually turn faster than the outer stages. The more popular engines seen on airliners use three stages, and three different speeds at any given time. Watch a modern airliner engine during engine start and you can hear the inner stages begin to spin up before you will see the outer fan stage begin to rotate. It depends on the engine, but the largest fan stage which is seen in the intake will be less than 10k rpm, often less than 5k.
How can aircraft fly without and engine?
an engine-less aircraft is more likely to glide than fly. It may gain altitude by riding on updrafts though.
What is the most recent developed engines for a plane?
There are a number of engines currently under development for aircraft.These include:Prop-fan - a mixture of a turboprop and a turbofan where the fan casing is removed to reveal a 'propeller' like fan, which is placed at the rear of the engine to eliminate the need for long shafts. Prop-fans are proposed to be much more efficient than any existing turbine engine and is designed for use on short - medium range passenger aircraft.Scimitar: An engine under development by Reaction Engines Limited in the United Kingdom which is designed for use on Supersonic aircraft cruising at Mach 5It uses Hydrogen fuel and makes use of a pre-cooler which uses the very cold liquid nitrogen fuel to cool the hot, compressed air entering the engine. This makes it extremely efficient at such high speeds.
What does altitude do to the air pressure?
makes 40% oxygen than lower altitude
What condition will true altitude be lower than indicated altitude?
high temperatures
How is density and altitude related?
They are relted because as the altitude increases than the density will alwways decrease.
What does a turboprop do?
Answer:The combination of the words turbine and propeller in techno jargon will give you the word "turboprop". A turboprop engine is a turbojet (gas turbine) engine, which powers the propeller/s. A conventional jet engine produces its thrust in large part due to the heated gasses escaping out the rear of the engine. While this is very useful for aircraft which fly at high speeds and high altitudes, it is less desirable for aircraft which are designed to fly at slower speeds and take off from smaller runways.A turboprop engine is a jet engine which converts the bulk of its thrust into rotational energy for powering a propeller. This allows jet engines, which are a high-rpm low-torque engine to be used in situations where low-rpm and high-torque are needed instead.The higher reliability and efficiency of a jet or turboprop engine as compared to an internal combustion engine makes them very desirable for aircraft designs which, in the past, would have utilized internal combustion engines.Answer 2A turboprop is a jet engine with a propellor attached - a jet engine is a turbine (fan) that compresses a large volume of air for combustion in a chamber as a opposed to a piston - a turbo charger on steroids - the propellor is attached to the central shaft of the fan blades - the two exhaust tubes on either side of the front of the turboprop are for the jet exhaust and it actually can add to the speed of the aircraft - the jet engine is usually backwards on a turboprop, the air intake under the engine is sent to the back which is really the front of the jet turbine, compressed by the fan blades (which drive the propellor) then sent to the combustion chamber where it is mixed with fuel and ignited - then exits through the exhaust tubes which bend to point backwards adding to the total thrust of the engine Often the word turboprop is confused with turbo charged which is a regular piston engine that uses a turbo charger (air compressor) - the P-38 lightning twin boom fighter of WW2 is a great example of a turbocharged engine and once you hear the sound the turbo chargers make you never forget itTurbo prop engines address a need for a compromise between propellor and jet engines - propellors are efficient at slow speeds to about 350 mph (meaning the amount of fuel used for speed and range) and dont have as much power as a jet - jets are effecient from about 300mph up and are more powerful than a piston engine but use more fuel - a turbo prop has nearly the power of a jet without as much fuel use and fills the gap for a mid range speed of about 200 to 400 mph - rarely see turboprops on low speed aircraft because of the extra fuel use with exception of some STOL bush style aircraft like the cessna caravan and the new quest kodiak that need the extra power for short/rough field useAlso turbo props can reverse thrust like a jet engine but do so usually by changing the angle of the propellor blades - another big advantage over piston engines for short runways - also turboprops use jet fuel since they are jet engines so they are being used more frequently in countries outside USA where avgas is becoming hard to find (not much general aviation aircraft but lots of jet airliners in many countries)A big advantage to using turboprops is how long they can be flown before a complete overhaul - the time can vary a lot by engine but an average time for a piston engine is about 1800 to 2000 hours and a turbo prop about 3000 to 3600 hours - so you can fly a turboprop a whole lot longer between major overhauls.
How fast does the turbofan go?
A turbofan engine is the most modern variation of the basic gas turbine engine. As with other gas turbines, there is a core engine, whose parts and operation are discussed on a separate page. In the turbofan engine, the core engine is surrounded by a fan in the front and an additional turbine at the rear. The fan and fan turbine are composed of many blades, like the core compressor and core turbine, and are connected to an additional shaft. All of this additional turbomachinery is colored green on the schematic. As with the core compressor and turbine, some of the fan blades turn with the shaft and some blades remain stationary. The fan shaft passes through the core shaft for mechanical reasons. This type of arrangement is called a two spool engine (one "spool" for the fan, one "spool" for the core.) Some advanced engines have additional spools for even higher efficiency.How does a turbofan engine work? The incoming air is captured by the engine inlet. Some of the incoming air passes through the fan and continues on into the core compressor and then the burner, where it is mixed with fuel and combustion occurs. The hot exhaust passes through the core and fan turbines and then out the nozzle, as in a basic turbojet. The rest of the incoming air passes through the fan and bypasses, or goes around the engine, just like the air through a propeller. The air that goes through the fan has a velocity that is slightly increased from free stream. So a turbofan gets some of its thrust from the core and some of its thrust from the fan. The ratio of the air that goes around the engine to the air that goes through the core is called the bypass ratio.Because the fuel flow rate for the core is changed only a small amount by the addition of the fan, a turbofan generates more thrust for nearly the same amount of fuel used by the core. This means that a turbofan is very fuel efficient. In fact, high bypass ratio turbofans are nearly as fuel efficient as turboprops. Because the fan is enclosed by the inlet and is composed of many blades, it can operate efficiently at higher speeds than a simple propeller. That is why turbofans are found on high speed transports and propellers are used on low speed transports. Low bypass ratio turbofans are still more fuel efficient than basic turbojets. Many modern fighter planes actually use low bypass ratio turbofans equipped with afterburners. They can then cruise efficiently but still have high thrust when dogfighting. Even though the fighter plane can fly much faster than the speed of sound, the air going into the engine must travel less than the speed of sound for high efficiency. Therefore, the airplane inlet slows the air down from supersonic speeds.
What is the difference between a negative the altitude and a positive altitude?
Altitude describes an object's position relative to sea level. An object in a position higher than sea level would have a positive altitude, sea level would have an altitude of zero, and any object below sea level would have a negative altitude.
Why is there a maximum altitude for aircraft?
After the maximum altitude is reached the preesure is so much that the pilot cant go farther. If he goes more than the maximum altitude he will lose consiousness.
