Crossword clues for turboprop
Longman Dictionary of Contemporary English
Wiktionary
n. A type of gas turbine aircraft engine that drives and obtains essentially all thrust from an external (typically unducted) propeller.
WordNet
n. airplane powered by a turbojet engine [syn: turbojet]
an airplane with an external propeller that is driven by a turbojet engine [syn: propjet, turbo-propeller plane]
Wikipedia
A turboprop engine is a turbine engine that drives an aircraft propeller. In contrast to a turbojet, the engine's exhaust gases do not contain enough energy to create significant thrust, since almost all of the engine's power is used to drive the propeller.
The propeller is coupled to the turbine through a reduction gear that converts the high RPM, low torque output to low RPM, high torque. The propeller itself is normally a constant speed (variable pitch) type similar to that used with larger reciprocating aircraft engines.
Turboprop engines are generally used on small subsonic aircraft, but some aircraft outfitted with turboprops have cruising speeds in excess of 500 kt (926 km/h, 575 mph). Large military and civil aircraft, such as the Lockheed L-188 Electra and the Tupolev Tu-95, have also used turboprop power. The Airbus A400M is powered by four Europrop TP400 engines, which are the third most powerful turboprop engines ever produced, after the eleven megawatt-output Kuznetsov NK-12 and 10.4 MW-output Progress D-27.
In its simplest form a turboprop consists of an intake, compressor, combustor, turbine, and a propelling nozzle. Air is drawn into the intake and compressed by the compressor. Fuel is then added to the compressed air in the combustor, where the fuel-air mixture then combusts. The hot combustion gases expand through the turbine. Some of the power generated by the turbine is used to drive the compressor. The rest is transmitted through the reduction gearing to the propeller. Further expansion of the gases occurs in the propelling nozzle, where the gases exhaust to atmospheric pressure. The propelling nozzle provides a relatively small proportion of the thrust generated by a turboprop.
Turboprops are most efficient at flight speeds below 725 km/h (450 mph; 390 knots) because the jet velocity of the propeller (and exhaust) is relatively low. Due to the high price of turboprop engines, they are mostly used where high-performance short-takeoff and landing ( STOL) capability and efficiency at modest flight speeds are required. The most common application of turboprop engines in civilian aviation is in small commuter aircraft, where their greater power and reliability over reciprocating engines offsets their higher initial cost and fuel consumption. Turboprop airliners now operate at near the same speed as small turbofan-powered aircraft but burn two-thirds of the fuel per passenger. However, compared to a turbojet (which can fly at high altitude for enhanced speed and fuel efficiency) a propeller aircraft has a much lower ceiling. Turboprop-powered aircraft have become popular for bush airplanes such as the Cessna Caravan and Quest Kodiak as jet fuel is easier to obtain in remote areas than is aviation-grade gasoline ( avgas).
Usage examples of "turboprop".
On that first visit, the bumpy, prayer-inducing descent in the turboprop persuaded me that the four-hour drive from Denver up through the Rockies, high, winding, fenceless passes and all, was the less intimidating choice.
We got it turboprop engines reverbrated through the interior with a all under control.
And while the upper probe had those massive free-flight turboprops, there was no indication of any engines at all on the lower ovoid.
I had my usual trouble with forms, but we made it and boarded a Tropicair Cessna Grand Caravan (15 seats including the pilot, and a single turboprop engine).