Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.ssau.ru/files/education/metod_2/pigareva_sovremen_la.pdf Дата изменения: Tue Dec 9 17:27:16 2014 Дата индексирования: Mon Apr 11 02:26:41 2016 Кодировка: Поисковые слова: п п п п п п п п п п п п п п п п п п п

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( Modern Aircraft)
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2008


143.21 43 .. : .. , .. . : . . . / . .. , .. . - : . . . -, 2008. ­ 80 . , «English for Specific Purposes». , , , , . . 2 .

143.21 43

© , 2008

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UNIT 1
An - 70 - New Step in the Development of Transport Aviation. Preparing to read. 1. Here is the title of the text "An-70 New Step in the Development of Transport Aviation". Try to predict how the text begins. The two first sentences will be displayed on the blackboard. 2. Write down three important facts related to the topic 'An -70-New Step in the Development of Transport Aviation'. Share the information and discuss it. 3. Match the keywords with their translations............ ................................... 1) to be intended for 2) long-haul 3) short take-off run 4) latitude 5) multiplexed data exchange channel 6) telpher 7) winch 8) to airdrop the paratroops 9) coaxial fans 10) contraption 11) container handling 12) airworthiness a) b) c) d) e) f) g) h) i) j) k) l)

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Reading 1. Read the text and check if your answers in ex. 2 p.1 are correct. 2. Read the text and complete the table below. Data on aircraft An-70 Types engines Cargo capacity Range Speed Runways Avionics Control systems of Advantages (in comparison with other types of aircraft)

An - 70 - New Step in the Development of Transport Aviation A. An - 70 is a long - haul short take - off military transport plane intended for airlifting military cargo of total mass of up to 47t. B. The plane can airlift 20 - 35t of cargo on 3800 - 7400km distance at 750kmph cruising speed , airdrop the paratroops and hardware, including single pieces weighing up to 20t,from either high or low altitude, bring in 300 troops with their small arms, evacuate 206 sick and wounded.
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C. Depending on the operational mode and cargo mass, An ­70 can take off from the average - strength concrete runways 1800m long, or the loosely - bound ground airstrips 600 - 900m long. In the latter case it carries 20-35t of cargo on 1450 3000km distance. D. Four D - 27 engines with coaxial fans ensure high cruising speed at 20 - 30% lower fuel consumption, comparing with other modern turbojets. E. The integrated digital avionics provide for steady operation of the plane by day or night, at every latitude in any weather, flights over the blank terrain, air-defence penetration, formation flights, take-offs from and landings on the unprepared ground airstrips. The use of multiplexed data exchange channels makes for an easy adaptation of avionics to any mission profile. F. In-built load - carrying contraptions enable the plane to load and unload the cargo, as well as airdrop it. They include four electric telphers of total carrying capacity of 12t, two electric winches having the pull of 1.5 t each. On customers demand the plane can be equipped with the second easily demountable deck or rollways for container-handling. G. On - board control & diagnostic systems allow An -70 to operate autonomously without any special ground infrastructure. All maintenance is done when the conditions so require. H. An ­ 70's high technical and operational potential makes it possible to built upon its base a whole range of models, both military and civil : early warning aircraft , flying command post, patrol aircraft, refuel aircraft and many various An-70T commercial transports. I. In 1998 the International Consortium of Medium Transport Aircraft has been set up which founders, beside Antonov Aeronautical Scientific Technical Complex , include the Russian and Ukrainian aviation factories, scientific Consortium conducts joint R & D , production , export. Its prime objective is the long- term pooling of the financial, industrial and human resources for the successful certification, production, sale, and leasing and after-sale support of An-70. Consortium is the sole legal entity having the right to built An-70 and alter its design. At present An - 70 is undergoing
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flight and certification tests for its compliance with the Air force's requirements and AP-25 (FAR-25, JAR-25) airworthiness criteria. Comprehension Check 1. Divide the text into logical parts and entitle them. 2. Answer the questions below. 1) What is An-70 intended for? 2) How many people can it evacuate? 3) What runways can the aircraft take off? 4) What ensures high cruising speed? 5) What provides for steady operation of the plane by day or night, at every latitude in any weather? 6) What enables the plane to load and unload the cargo? 7) What systems allow An-70 to operate autonomously without any special ground infrastructure? 3. Define the main idea of paragraphs E and F. Find the supporting details that help to develop the main idea. 4. Explain why: a) An-70 can take of and land on the unprepared ground airstrips. b) The avionics can be easily adapted to any mission profile. c) An-70 has a lower (20-30%) fuel consumption comparing with other modern turbojets. d) It is possible to build upon An-70's base a whole range of models, both military and civil. e) An-70 can operate autonomously without any special ground infrastructure.
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Vocabulary Focus 1. Fill in the gaps with the words & expressions from the box.

consortium special ground infrastructure mission profile wounded

multiplexed ground airstrips concrete runways channels

sick

hardware.

1) An-70 can airdrop the paratroops and 206 bound any . . and .

; it can evacuate 1800 long, or the loosely-

2) An-70 can take off from the average-strength 600-900m long. data exchange 3) The use of

makes for an easy adoption of the avionics to

4) On-board control and diagnostic systems allow An-70 to operate autonomously without any 5) is the sole legal entity the right to built An-70 and alter its design.

2. Explain the following words and word combinations in other words or give synonyms where it is possible. A long haul aircraft, to be intended for(A), to airdrop the paratroops (B); formation flights , unprepared airstrips (E); contraption, a demountable deck (F); in compliance with, airworthiness criteria, customer (I). 3. Translate from Russian into English. 1) -70 , 47 .
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2) , 1800 .

, -70

-

3) D-27 20-30%, . 4) -70 - . 5) -70 , : , , , - . 6) , -70 . Focus on writing 1. Rearrange the following words to form meaningful sentences. Work in groups. 1) cargo / An-70 / intended for / up to 47t / of / total mass / of / a/ military / long haul/ plane / transport / short take-off / military / airlifting / is. 2) speed / SV-27 coaxial fans / turbojets / with / high / consumption / at 20-30% lower / four D-27 engines / with / modern / fuel / ensure / other / cruising / comparing. 3) weather / every / in / latitude / any / at / for / avionics / operation / the / plane / integrated / of / digital / the / night / by / day / or / provide. 4) enable / load-carrying / to load / in-built / as / contraptions / the / unload / the cargo/ it / plane / airdrop / well / as / and. 5) requirements / at / is / certification / with / its / present / the Air force's / and / undergoing / AP-25 / criteria / An-70 / flight / airworthiness / compliance / tests.
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2. Use the prepositions in the box to complete the sentences. in up to 1) An-70 can take off on with for at over of without from by

the average-strength concrete runways 1800m long.

2) It carries 20 - 35t ____ cargo ____ 1450 - 3000km distance. 3) An - 70 is intended ____ airlifting military cargo of ____ 47t. 4) Four D - 27 engines ensure high cruising speed ____ 20 - 30% lower fuel consumption, comparing ____ other modern turbojets. 5) The integrated digital avionics provide ____ steady operation of the plane ____ day or night ____ every latitude ____ any weather, flights ____ the bank terrain . 6) ____ customers demand the plane can be equipped ____ the second easily demountable deck or roll - ways ____ container - handling. 7) On-board control and diagnostic systems allow An-70 to operate autonomously ____ any special ground infrastructure. 3. Write a summary of the text. Speaking 1. a) Read the text again. Find the details and fill in the table. Loadcarrying contraptions Maintenance Integrated digital avionics International Consortium (founders and activity)
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b) Speak on the points from the table. Work in pairs. c) Research any new transport aircraft and compare its performances with An 70. 2. Work in groups. You are involved in developing of different systems or parts of the aircraft. Today you are to make a report to your boss. You are responsible for one of the following topics: - engines - avionics - loading and unloading - control systems - flight performances - ICMTA (Consortium) 3. Choose the topic to speak on. Invent and develop your own ideas for aircraft improvements.

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UNIT 2 American Eagles Preparing to Read 1. Look at the title of the text ''American Eagles ''. Write down 10 words that may be related to the topic. Then work in pairs, share the words and give your prediction about the contents of the text. 2. Look at the following list and try to guess what type of aircraft it is. Work in groups and share the information. extremely maneuverable air superiority unprecedented avionics high engine thrust-to-weight ratio tactical electronic-warfare system air-to-air weaponry advanced radars turn without loosing airspeed electronic countermeasure set weapon control stick 3. Match the English words with their Russian counterparts. 1) throttle 2) interdiction 3) ground clutter 4) redundant 5) avionics 6) air intake trunk a) () b) , c) , d) . e) - f)
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7) thrust-to-weight ratio 8) precision 9) versatile 10) control stick 11) dogfight 12) adverse weather 13) to acquire enemy aircraft 14) head-up display

g) h) k) l) m) n) o) p)

American Eagles A. The F-15 Eagle is an all-weather, extremely maneuverable, tactical fighter

designed to permit the Air Force to gain and maintain air superiority in aerial combat. B. The Eagle's air superiority is achieved through a mixture of unprecedented maneuverability and acceleration, range, weapons, and avionics. The F-15 has electronics systems and weaponry to detect, acquire, track and attack enemy aircraft while operating in friendly or enemy-controlled airspace. C. The weapons and flight control systems are designed so one person can safely and effectively perform air-to-air combat. The F-15 superior maneuverability and acceleration are achieved through high engine thrust-to-weight ratio and low wing loading. Low wing-loading (the ratio of aircraft weight to its wing area) is vital factor in maneuverability and, combined with the high thrust-to-weight ratio, enables the aircraft to turn tightly without losing airspeed. D. A multimission avionics system sets the F-15 apart from other fighter aircraft. It includes a head-up display, advanced radar, inertial navigation system, flight instruments, ultrahigh frequency communications, tactical navigation system and instrument landing system. It also has an internally mounted tactical electronicwarfare system, identification "friend or foe" system, electronic countermeasures set and a central digital computer.
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The head-up display projects on the windscreen all essential flight information gathered by the integrated avionics system. This display, visible in any flight condition, provides the pilot information necessary to track and destroy an enemy aircraft without having to look down at cockpit instruments. E. The F-15`s versatile pulse-Doppler radar system can look up at highflying targets and down at low flying targets without being confused by ground clutter. It can detect and track aircraft and small high-speed targets at distances beyond visual range down to close range, and at altitudes down to treetop level. The radar feeds target information into the central computer for effective weapons delivery. For close-dogfights, the radar automatically acquires enemy aircraft, and this information is projected on the head-up display. The F-15`electronic warfare system provides both threat warning and automatic countermeasures against selected threats. F. A variety of air-to-air weaponry can be carried by the F-15. An automated weapon system enables the pilot to perform aerial combat safely and effectively, using the head-up display and the avionics and weapons control stick. When the pilot changes from one weapon system to another, visual guidance for the required weapon automatically appears on the head-up display. G. The Eagle can be armed with combinations of four different air-to-air weapons: Aim-7F/M Sparrow missiles or AIM-120 advanced medium range air-to-air missiles on its lower fuselage corners, AIM-9L/M Sidewinder or AIM-120 missiles on two pylons under the wings, and an internal 20mm Gatling gun in the right wing root. Low-drag conformal fuel tanks were especially developed for the F-15C and D models. Conformal fuel tanks can be attached to the sides of the engine air intake trunks under each wing and are designed to the same load factors and airspeed limits as the basic aircraft. Each conformal fuel tank contains about 114 cubic feet of usable space. These tanks reduce the need for in-flight refueling on global missions and increase time in the combat area. All external stations for munitions remain available with the tanks in use. AIM -7 F/M Sparrow missiles, moreover, can be attached to the corners of the conformal fuel tanks. H. The F-15E is a two-seat, dual-role, totally integrated fighter for all- weather, airto-air and deep interdiction missions. The rear cockpit is upgraded to include four
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multi-purpose CRT displays for aircraft systems and weapons management. The digital, triple-redundant flight control system permits coupled automatic terrain following, enhanced by a ring-laser gyro inertial navigation system. For low altitude high-speed penetration and precision attack on tactical targets at night or in adverse weather, the F-15E carries a high-resolution APG-70 radar and low attitude navigation and targeting infrared for night pods. Reading 1. Read the text and write out the words and word combinations you don`t know, try to guess their meaning from the context. Compare your notes with your partners. to penetrate conformal fuel tank threat warning system a head-up display ground clutter air intake trunk dogfight identification friend or foe electronic warfare system engine throttle deep interdiction mission redundant control stick to acquire the aircraft

2. Read the text while reading find out the necessary information and fill in the following table.

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Comprehension Check 1. Read the following statements. Say weather they are true; if not, correct them. 1) The weapons and flight control systems are designed so five pilots can safely and effectively perform air-to-air combat. 2) The F-15 Eagle is an all-weather, extremely maneuverable, tactical fighter. 3) Its maneuverability and acceleration are achieved through aspect ratio and low wing loading. 4) The head-up display projects on the windscreen only a small amount of information gathered by the integrated avionics system. 5) The radar feeds target information into central computer for effective weapons delivery. 6) The F-15`s electronic warfare system provides only threat warning and doesn`t provide automatic countermeasures against selected threats. 7) The Eagle can be armed with combinations of one air-to-air weapon - AIM-7F/M Sparrow missiles. 8) Low-drag conformal fuel tanks were especially developed for the F-15C and models. 9) Conformal fuel tanks reduce the need for in-flight refueling on global missions and increase time in the combat area. 10) The F-15E is a two-seat, dual-role, totally integrated fighter for all-weather, airto-air and deep interdiction missions. 2. Ask questions to which the following sentences are the answers. Remember to use "wh" words: why, what, where, when. Work in groups. 1. ____designed to permit the Air Force to gain and maintain air superiority in aerial combat. 2. ____through a mixture of unprecedented maneuverability and acceleration, range, weapons and avionics. 3. ____ the weapons and flight control systems. 4. ____ it sets-the F-15 apart from other fighter aircraft.
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5. ____ projects on the windscreen all essential flight information gathered by the integrated avionics system. 6. ____The F-15`s versatile pulse - Doppler radar system. 7. ____ enemy aircraft. 8. ____both threat warning and automatic countermeasures against selected threats. 9. ____ enables the pilot to perform aerial combat safely and effectively. 10. ____ when the pilot changes one weapon system to another. 11. ____ with combinations of four different air-to-air weapons. 12. ____ low-drag, conformal fuel tanks. 13. ____ about 114 cubic feet of usable space. 14. ____ the digital, triple redundant flight control system. 15. ____ a high resolution APG-70 radar and low altitude navigation and targeting infrared for night pods. Vocabulary Focus 1. Find in the text the synonyms to the given words and expressions. a battle in the air distance aviation electronic equipment to do smth. better than others to win in the battle to fulfill essential to be fitted to crash, to defeat the enemy 2. Match the words with their definitions. 1. aircraft acquisition 2. wing-loading
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multifunctional menace (danger) warning upgraded accuracy bad weather to collect information

a) the armament intended for battles in the air b) danger


3. multimission avionics 4. air-to-air weaponry 5. ground clutter 6. threat 7. air intake tranks

c) a special channel for sucking in the air for ventilation d) the detection of the aircraft e) the ratio of aircraft weight to its wing area f) ground interference g) a versatile radio electronic on-board equipment

3. Express the same in English. ; ; ; ; , ; ; « - »; () ; ; ; ; -; ; ; ; ; ;



; . Focus on Writing 1. Match the beginnings and the endings of the sentences. 1) The air's superiority is achieved ... 2) The weapons and flight control systems are designed so ... 3) The F-15 superior maneuverability and acceleration are achieved... 4) A multimission avionics system sets the F-15... 5) The head-up display projects on a) about 114 cubic feet of usable space b) four different air-to-air weapons c) visual range down to close range, and at altitudes down to treetop level d)four multi-purpose CRT displays for aircraft systems weapons management e) through a mixture of unprecedented maneuverability and acceleration,
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the windscreen all essential flight information... 6) The F-15 pulse-Doppler radar system can detect and track aircraft and small high-speed targets at distances beyond... 7) The Eagle can be armed with combinations of... 8) Each conformal fuel tank contains... 9) The rear cockpit is upgrated to include 10) For low altitude, high-speed penetration and precision attack on tactical targets at night or in adverse weather...

range, weapons, and avionics f) the F-15E carries a high-resolution APG-70 radar and low attitude navigation and targeting infrared for night pods g) one person can safely and effectively perform air-to-air combat h) apart from other fighter aircraft i) gathered by the integrated avionics system j) through high engine thrust-toweight ratio and low wing loading

2. Make up your own sentences using the words and word combinations of exercise 1 p. 17 3. Write a summary of the text. Speaking 1. You are going to introduce your aircraft at Farnborough Air Show in the United Kingdom. Describe the performances of American Eagles and persuade the potential customers to purchase the aircraft from your company. Split into groups. Everyone should take part in presentation (remember to use the table ex.2 p.12) . Speak about: 1- radar systems of the aircraft 2- fuel system 3- weapons 4- the head-up display 5- flight performances
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UNIT 3 Sukhoi S-37 ``Berkut`` 5th Generation Russian Fighter Preparing to read 1. Write 3 important factors related to the topic. 2. The beginning of the sentence is displayed on the blackboard. Can you predict how the text begins? Share your ideas with your group mates. Reading 1. Skim the text and try to guess the meaning of the underlined words from the contents of the text. Sukhoi S-37 ``Berkut`` 5th Generation Russian Fighter A. Sukhoi S-37 "Berkut", Russian's 5th generation fighter. New in Sukhoi fighters forward-swept wing design integrated into the tandem triplane configuration. Visible in the tail section of the aircraft are two "stringers". A rather interesting element: the "stringers" are of different length. At first it might appear that this is an optical illusion, however, after a closer examination the difference in length of the "stringers" is obvious. It is reasonable to conclude that the longer "stringer" contains a spin-recovery parachute. However, the difference in size of the "stringers" can also be explained by a possibility of an aft facing radar. B. The S-37 fighter is designed to use the thrust-vectoring AL-37FU engines, however, during the first test flights it was used the more powerful D-30F6 engines from MiG-31, Russia's most advanced high-speed interceptor aircraft. The original, 1991 S-37 project was a smaller aircraft with a delta wing design and a single AL41F engine. This apparently was not the case with the 1997 S-37 "Berkut" : the new aircraft is significantly larger, it is equipped with two engines, and employs a forward-swept wing design. The combined thrust of S-37's engines is 25 tons.
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C. The basic dimensions and weight of the S-37 "Berkut" are similar to those of Su37. While the main advantage of the forward-swept wing design is the improved maneuverability at subsonic speeds and high angles of attack, its primary drawbacks are the reduced lift and handling problems at supersonic speeds. A natural way to counter such problems is by using more powerful engines and advanced thrustvectoring controls. The 1991 S-37 project was designed with very powerful AL-41F engines in mind. The AL-441F would be able to satisfy the power requirements of the S-37. D. The S-37 has large canards mounted on the intake side, close to the leading edge of the forward-swept wing. It is also apparent that the vertical stabilizers are canted slightly outward, and not inward. Two large auxiliary intake doors are located on the centre fuselage section. It previously suggested that the nose section of the S-37 was similar to the one of Su-27 family. However, later it became clear that it is rather similar to the original S-37 design announced in 1991 and later canceled. It is now clear that the S-37 fighter is intended to become Russia's fifth generation fighter. Main characteristics: - 75 feet long - inverted-arrow wing design - two thrust-vectoring engines - tandem triplane configuration - reduced RCS airframe - airframe is covered with radio wave absorbent. Dimensions: Wingspan 15.65m Length 22.2m Height 6.36m Powerplant: Two afterburning, thrust-vectoring Saturn/Lulka AL-37FU with digital controls; Thrust (each): 83.35kN dry;142.2kN with afterburning; Thrust-vectoring in pitch -20* to 20* at 30* per second.
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Weight: Normal take-off 26000kg MTOW 34000kg Performance: Max level speed at sea level 760kt (1400km/h) Max rate of climb at sea level 230m/sec Service ceiling 18800m Range (armed, internal fuel) 3880km Required runway length 1200m Armament: One GSh-30 30mm cannon with 150 rounds; Two R-73 and two R-27 missiles carried under the fuselage on special conformal suspensions. There are no armaments under the wing, but as need be it can be placed on underwing pylons. 2. Read the text and find the meaning of the following equivalents. Consult a dictionary. - spin-recovery - forward-swept wing - thrust-vectoring controls - conformal - suspension - canards - tandem triplane configuration 3. Read the text and search for the detailed information on the following: -wing configuration (its advantages and disadvantages) -engines -armaments -performance -powerplant

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Comprehension Check 1. Divide the text into logical parts and entitle them. 2. Answer the questions: 1) What kind of aircraft is the Sukhoi S-37 "Berkut"? 2) What new is in the wing design of the aircraft? 3) What is visible in the tail section of the aircraft? 4) Are the "stringers" of different length? 5) How can the difference in size of the "stringers" be explained? 6) What kind of engines is it powered by? 7) What are the basic dimensions and weight of the S-37 "Berkut"? 8) What is the main advantage of the forward-swept wing design? What are the drawbacks? 9) What kind of engine would be able to satisfy the power requirements of the S-37? 10) Are the vertical stabilizers canted slightly outward and not inward? 11) Are two large auxiliary doors visible on the center fuselage section? 12) The airframe is covered with radio wave absorbent, isn't it? 13) What thrust can each engine develop? 14) What range can it fly? 3. Make up a summary of the text. Vocabulary Focus 1. Find the words in the text that mean: - push - improved - decreased - advanced - outside
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- inside - ban - to be alike - obvious 2. Explain the meaning of the following words: - triplane - interceptor - maneuverability - canards - armament - afterburning 3. a) Find the equivalents in the text: - - - - - - - - b) Make up 4-5 sentences with these words. 4. Fill in the gaps. 1) The difference in size of the stringers can be also explained by ...... . 2) One of the most interesting and confusing technical issue about the new Russian fighter is its ...... . 3) The basic dimensions and weight of the S-37 "Berkut' are similar to those of ....... . 4) The S-37 fighter has large ...... mounted on the intake side, close to the leading edge of the ..... . 5) Its primary drawbacks are ...... lift and handling problems at ..... speeds. Engines; reduced; SU-37; radar; supersonic; canards; forward-swept wing.
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Focus on writing 1. Complete the sentences. 1) New in Sukhoi fighters forward-swept wing design integrated into the ....... . 2) It is reasonable to conclude that the longer "stringer" contains a ....... . 3) The S-37 fighter is designed to use the ......... . 4) During the first test flights it was used the more powerful D-30F6 engines from ...... , Russia's most advanced high-speed ..... ..... . 5) The original, 1991 S-37 project was a smaller aircraft with a ..... wing design and a ..... AI-41F engine. 6) This apparently wasn't the case with the 1997 S-37 "Berkut": the new aircraft is significantly larger, it is equipped with two engines and employs a .... .... .... design. 7) The basic dimensions and weight of the S-37 "Berkut" are similar to those of ....... . 8) The main advantage of the forward-swept wing design is the .... ..... ..... ..... . 9) The drawbacks are the .... ..... and ..... ..... at supersonic speeds. 10) It previously suggested that the nose section of the S-37 was similar to the one of .... family. 2. Make up meaningful sentences from the following words: 1. is/ engines/ fighter/ to use/ the thrust-vectoring/ the S-37/ designed 2. intake/ section/ large/ are located/ two/ fuselage/ auxiliary/ centre/doors/ on the 3. canards/ side/ the Su-37/ intake/ has/ on the/ large/ mounted 4. wave/ the airframe/ with/ absorbent/ is/ radio/ with 5. the S-37 fighterussia`s/ it/ that/ to become/ fighter/ clear/ fifth/ now/ is/ is intended/ generation Speaking 1. Work in pairs. Your authorities give you the task to introduce some improvements of aircraft Su-37. Cooperate and prove your point of view speaking on your improvements.
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UNIT 4 Vertical Horizons Preparing to read 1. 2. Read the title of the text and think of all possible terms that may relate to Work in pairs. Share the words and give your prediction about the content

the topic. of the text. Reading 1. Skim the text and try to guess and explain the meaning of the underlined words or word ­ combinations. Vertical Horizons

A. People have dreamed of taking off and landing vertically for as long as they have dreamed about flying. But today the two classes of air vehicle remain fundamentally fixed-wing distinct: those that hover efficiently and those that fly efficiently. Closing the gap between rotary-wing and fixed-wing aircraft is the dream of vertical flight proponents, and designers are pursuing two paths: improving the efficiency of helicopters and perfecting new configurations. B. The first "free" vertical flight was made by Frenchman Paul Cornu in 1907, barely four years after the Wright brother's first flight, but the machine was impractical. Autogyros became quite sophisticated between the wars, but they were not true vertical take-off and landing (VTOL) machines. The first practical helicopters were the German side-by-side rotor Focke-Angelis Fa61 of 1936 and intermeshing-rotor Flettner Fl282 of 1941. But Igor Sikorsky's VS300 defined the modern single-rotor helicopter when it first flew in 1939.

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C. Despite all the technological progress since then, helicopters remain niche players in aviation. Compared with equivalent fixed-wing aircraft, they are still more expensive to buy and costly to operate; they are too noisy inside and out; and they vibrate too much for the comfort of their occupants or the longevity of their components. Yet helicopters are arguably the most versatile and useful of air vehicles. Room for improvement D. There is still considerable development potential in conventional helicopter, albeit incremental. Higher speeds, heavier payloads, less noise and vibration, and lower production and operating costs are possible. Typical industry goals for a 2020timeframe helicopter include a 200kt (370km/h) cruise speed; 30% reductions in empty weight and fuel consumption; 60%lower external noise; fixed-wing levels of vibration and safety; 30-50% lower development, production, operation and maintenance costs; and all-weather operability. E. The latest helicopters can cruise at up to 160kt, but this is an economical, rather than physical barrier. At 160kt the power required in forward flight is close to the power required in hover; to increase speed the power required in level flight has to be reduced. This will