The Modern Flight

Authors: RVV. Petrescu and FIT Petrescu

Abstract: A modern flight involves both a great flight quality and high safety throughout. You can’t speak of a quality of flight today unless it provides increased comfort to all passengers in full safety and relaxation. Regardless of the aircraft design type, a minimum level of comfort is required in the passenger cabin so that they feel safe, comfortable, quiet, plus not having the time to get bored if the flight is longer, but to keep constant the sensation of pleasure. For longer journeys, passengers must have the feeling of a vacation and not of a travel that doesn't over. Today, modern ships struggle to provide passengers with extra comfort, who no longer have to look on the walls or on a possible common screen that diffuses a movie that is known or not interesting for passengers as being a bad movie of a bad cinema. Every passenger must have his own laptop, which he can work on, navigate, communicate, or watch a pleasant, personally chosen film so that time passes easily and quickly and the journey being one as special as possible. Another aspect of a successful journey is to ensure increased safety throughout it. This is not easy to accomplish, especially in modern, complicated times, with all sorts of dangers that can occur during a flight. Nor is the fact that the ship is giant, full of people, workers, supervisors, can not completely eliminate all the dangers of a possible terrorist attack on board or from outside the ship, the dangers of air voids, globular lightning, frost, birds, a completely free route ... A large mass of specialists is constantly working to solve these problems. The propulsion system of the ship and its maintenance in the air, are, in the opinion of the authors of this paper, the two essential factors of ensuring one safer flight. For this reason, the paper will focus on the modern propulsion systems of an aircraft and in the most normal way of keeping it in the air. The safest way to keep an airplane in the air known from the oldest to the present day is the use of a navigable airship. On such a flying device, which automatically keeps everything in the air, without the danger of collapsing, with minimal fuel and energy consumption, with great flight safety and high comfort, it is only the problem of the maximum speed of navigation, which may be limited by the high resistance of the aircraft to advance. When we have a pleasure trip, or one on short or medium distances, navigating with airships is always preferred. What can be done when the journey takes place over very long distances and travelers are rushed to arrive at the destination, with the high speed of the aircraft being a priority? At first glance, in such cases, an airship can no longer be used. And yet a modifiable one could be used successfully and in such situations. This is an essential point to be discussed during this work.

Keywords: Modern Flight, Flight Quality, High Safety, Some Special Aircraf, Helicopters, Aerospace, Spacecraft Propulsion, US Army, Jet Engines, Airships

Introduction

With Alpine wreckage still being sifted, this is either a very good or a very bad time to write about the mystery and beauty of aviation. I am a nervous flyer, always imagining the worst will happen, so when I hear that ‘the captain has turned off the seat-belt sign’ I feel a jolt of relief. Even more so when, halfway through the trip, the captain himself speaks to the passengers in a voice whose mellifluous calculation is as precise as the in-flight computers. You would always want the voice of the pilot to be Mark Vanhoenacker’s.

He is an unusual hybrid: a BA 747 pilot and, now, an author of real distinction with a genuinely poetic sensibility as well as a memorable turn of phrase. Although flight is the greatest modern adventure, it has been poorly served by literature. Writers, evidently, prefer grubby divorces in the suburbs to the majesty of aviation as a context for a discussion of human folly and ingenuity. There was the man-boy Saint-Exupéry, of course. Let’s not forget Biggles. And before Vanhoenacker there was Guy Murchie, whose Song of the Sky (1954) was the most eloquent and engaging account of what it takes to get into the air and what happens when you are up there.

Vanhoenacker has found a perfect voice for a glorious subject. He calls it Skyfaring because he is keenly aware of maritime parallels. Indeed, the aircraft industry speaks of ships, hulls, and rudders. He’s aware too of metaphors: ‘pilot’ itself being, since Aeneas’s Palinurus, one of the most resonant.

This pilot’s voice has gentle authority, calm assurance, a persistent, but not unpleasant, didacticism and a very nice sense of telling details. And all of this is informed by Vanhoenacker’s own privileged access plus a sense of wonder, refreshed daily, about how boggling it is that 380 tons of aluminium, titanium, steel, glass, rubber and duty-free can keep the population of a village aloft at seven miles above the ground while moving closer to the speed of sound (https://www.spectator.co.uk/2015/04/the-miracle-of-modern-flight-by-a-747-pilot-with-a-poets-sensibility/).

Now that so much of flying has become a sordid and humiliating ordeal, it is good to have an elegant corrective which restores some of its original romance. A recurrent theme is the strangeness of it all and how, at altitude, nothing is quite what it seems. Airborne, the earthbound laws of physics no longer quite apply. North turns to south, night becomes day while time and space are compacted this way and extended the next. Air, Vanhoenacker insists, is not ethereal nothingness, but a weighty gaseous soup which his aircraft manipulates and penetrates. We learn about winds, clouds and charts: ‘maps of transience and air’.

Did you know that Indicated Air Speed, True Air Speed and Ground Speed are all different? Did you know that pressure altimeters are always being re-set because pressure varies? Flight Level 35 is not always 35,000 feet; nervous fliers may wish to rehearse their anxiety about whether the flight crew have corrected their instruments to cold weather conditions vis-à-vis mountains expected en route. Then there is the radio altimeter which is so sensitive that its calculations account for the time electrons take to travel through a 747-400’s 274 kilometres of wiring.

But Skyfaring is not nerdy techno-porn. It is compulsive for the same reasons flight itself is compulsive: here is territory where the technical quickly blurs into the mystical. As he twiddles with the knobs on the ample abbreviations and acronyms in his cockpit, the GPWS (Ground Proximity Warning System) or the CAS (Collision Avoidance System), he takes a long, slow, left-hand turn into poetry. And sometimes into amusing bathos: ‘I saw the lights of all Baghdad pass by in the night, and then I ate a sandwich.’

Most of modern flight is automated, true. But I have actually done several hours on a 747 simulator and can testify that it’s wringingly exhausting both physically and intellectually. Most demanding of all is the awful responsibility: apart from officers in combat, no one holds so much life and death in the balance as a commercial airline pilot.

Dislocation and globalisation, epidemics and pollution are effects of flight. But so too are the beauty, poetry and mystery which are Vanhoenacker’s subject. As soon as the pilot says ‘Gear up!’, you enter a higher form of unreality. This really is a very good book.

One of the reasons that Steve Thorne’s Flight Chops video channel has become so successful is that he’s a digital pilot for a digital age. As he told us recently, it wasn’t until modern tools like the iPad and its bevy of flight-related apps came along that he felt like he could hit the sky and immerse himself in any and every aircraft he could find. However, that doesn’t mean he’s not willing to try things the old-fashioned way every now and then.

In this Throwback Thursday edition of Flight Chops, Thorne hits the sky in Dennis Simo’s 1942 Boeing PT-13/A75 Stearman, affectionately known as Miss Delish. A weekend warrior’s cross-country flight with nothing but paper – what could possibly go wrong? (https://www.flyingmag.com/flight-chops-what-happens-when-modern-pilot-flies-traditional-way).

Methods and Materials

LZ 127 the Zeppelin Grade (D-LZ 127) was a rigid aircraft, built only in Germany, for the purpose of carrying passengers powered by hydrogen as it was at that time, which operated commercially between 1928-1937. When he entered the commercial service in 1928, he became the first passenger transatlantic passenger service in the world. The name of the aircraft came from the German pioneer of aircraft, Ferdinand von Zeppelin, German nobleman [1-43]. During its operating period, the airship made 590 flights covering more than 1.7 million kilometers (over 1 million miles) of flight, extremely much for an air pioneer who was still created with not very special materials and its filling being made with hydrogen, a highly flammable gas. The ship was designed to be operated by a crew of 36 officers (men). The LZ 127 was the longest rigid aircraft at the time of its completion, being exceeded only by the USS Akron in 1931. It was dismantled for combat aircraft parts in 1940, in the Second World War (The Graf Zeppelin).

Zeppelin made his first flight on September 18, 1928, under the command of Hugo Eckener. The ship took off at 3:32 and flew just over three hours before returning to its base in Friedrichshafen.

A series of successful flights followed, including a 34 and a half hour endurance flight, during which the new German ship was presented to the residents of Ulm, Flensburg, Hamburg, Berlin, Leipzig and Dresden.

Zeppelin's chart made its first commercial passenger trip over the Atlantic, leaving Friedrichshafen at 7:54 on October 11, 1928 and landed at Lakehurst, New Jersey on October 15, 1928, after a flight of 111 hours and 44 minutes. The ship has transported 40 crew members under Hugo Eckener's command and 20 passengers, including US naval officer Charles E. Rosendahl and Hearst newspaper reporter Lady Grace Drummond-Hay.

The first transatlantic crossing of the ship was to end in disaster due to a strong storm on the morning of October 13th. Captain Eckener had entered unusual in the storm at maximum power and speed of the aircraft (it was known that the speed had to be reduced in adverse weather conditions) and the ship had risen in altitude violently because of the unexpected storm and the inexperienced crew member in charge of steering the altitude of the ship (the R-38 and USS Shenandoah airships have broken under similar circumstances), but the commander managed to control the ship and recover it on time, rapidly and very much reducing its travel speed.

Eckener and his officers were able to re-establish control of the ship as soon as their speed had fallen, but they soon found out that the lower wing coverage was broken by the wind, threatening additional damage that would make the ship uncontrollable. Eckener immediately sent a four-man repair team (including his son, Knut Eckener, senior elevator man and future zeppelin commander Albert Sammt and Ludwig Knorr, who will become chief executive on the LZ-129 Hindenburg) to repair the cover even in flight. At the same time, Eckener made the difficult decision to send a distress call, knowing he was in jeopardy for his ship's reputation. The distress signal was soon taken over by the press and newspapers around the world had the opportunity to tell sensational facts about the prolonged destruction of Graf Zeppelin, which happened during his trip over the Atlantic.

Emergency repairs were successful, but the ship encountered a second event, a new storm just ahead of Bermuda. The Zeppelin managed to cross the second storm even though it had a temporarily repaired wing, which has again deteriorated on the occasion of the second storm and managed to reach the US coast on the morning of October 15. After a roundabout from Washington, Baltimore, Philadelphia and New York, to show Zeppelin Graf to the American public, Eckener brought the ship damaged by a safe landing at the United States naval base at Lakehurst, New Jersey on the evening of the 15th October 1928. The Zeppelin chart was delayed, damaged and had just finished the food and water supplies, but Eckener, his crew and passengers were greeted as heroes with a band parade across Broadway in New York City. Always materials used to build aircraft have been a priority (Aversa et al., 2017a-e; 2016a-o; Mirsayar et al., 2017). But at that time, there were no possibilities of today in creating of materials.

The first crossing of the Atlantic in a crewed flight, using a navigable, demonstrated that such a ship can keep on flying even under extremely difficult conditions. Apart from the fact that the ship entered the first storm at very high speed, totally unprepared and poorly coordinated, a major problem was the used material that has been broken in front of a very strong wind (extremely high winds).

A modern airship, the Airlander, made from special materials can face a hurricane without great difficulty.

If a modern ship hits an unexpected hurricane, the modern materials that cover it have a very high pressure and impact resistance.

However, today any more dangerous storm is signaled early and can be bypassed or avoided by lifting the ship above the storm.

Speed does not need to be diminished anymore, but instead, the velocity may be increased to avoid the storm or even to take the ship out of the storm area.

A modern airship-like a dirigible ship can easily rise to very high altitudes, or it could even leave the earth's atmosphere without big fuel or energy loss, no pollution, no dangers.

Even more, she might as well return to the earth's atmosphere.

The US Navy has experimented with many original uses of airships. The most original of these was to use these aircraft as aircraft carriers. This is a consequence of the crisis of the 1930s. With the recession, budgets allocated to airships in the US armed forces are reduced.

It is ultimately up to the US Navy to develop the employment doctrine as well as the technology of these vessels. Aware of the vulnerability of these devices, the US Navy sailors quickly abandoned the idea of using them for offensive purposes, preferring to assign them to reconnaissance missions. It is within this framework of employment that the various possibilities of carrying airplanes in airships and the technologies and methods to be developed to design and operate such assemblies, will be explored. Two of the three airships were destroyed in accidents only two years after their commissioning.

Before the Second World War, competition between the airplane and the airship as an instrument of war and reconnaissance was still strong. Autonomy is an asset for the lighter than the air, but its maneuvering capabilities and its protections are limited, which makes it very vulnerable in combat situations. However, following the Treaty of Versailles in 1918, the Allies, intrigued by the success of the German military raids over Great Britain, appropriated the technology of the Zeppelin brand and in the United States was created the brand Goodyear-Zeppelin.

Very quickly, it is envisaged to equip the airships as aircraft carriers to assign them to reconnaissance missions, rather than to make them military apparatuses usable in combat. The losses of the German crews of the Zeppelins during the Great War had definitely limited the offensive interest of the dirigibles.

For example, in 1931, as soon as the ZR-4 Akron (which bears the name of the city where it was built) was to be built, was it planned to equip the Navy airships so that they could carry single-seater aircraft that they could dump and recover in flight. The same thing was planned for his "sistership" Macon (launched it two years later in 1933).

Initially, the primary purpose was to carry light aircraft used to increase the air reconnaissance capability of the airship. In the second phase, the biplanes on board were equipped with weapons systems, which could be used to ensure the safety of their mothership, in flight.

Resolutely new, these airships were responsible for developing a doctrine of employment. The cohabitation of a crew of pilots and balloonists was not without difficulty as to the elaboration of this doctrine, the airships post World War I being traditionally envisaged for missions of recognition and very little concerned with the offensive activities or freight. The pilot officers, emphasizing the intrinsic vulnerability of the airship, considered that the airship had to stay behind and use the aircraft taken for reconnaissance missions or even more offensive missions. The officers and crew of the Akron considered that the airship had to carry out the reconnaissance missions to which it had traditionally been assigned and to use the airplanes to ensure its air protection. The premature disappearance of the two airships Akron and Macon did not resolve this debate and put an end to the concept of aircraft airship before a doctrine could be elaborated.

But let's not forget that the materials used at that time did not have the special properties of today and the flight technique used then was very rudimentary.

The US Navy's two aircraft airships are original aircraft from the Navy's previous USS Los Angeles (ZR-3) research. They were built with an internal duralumin structure and three interior pins. The lift of the dirigible was obtained with 12 gas cells of gelatin and latex, filled with helium. Inside the structure, the ship carried eight 560 horsepower twelve-cylinder engines, designed by the German firm Maybach. These engines were diesel-powered. They were driven by external propulsion propellers. Propellers with propellers could be steered upwards or horizontally to control the airship during the take-off and landing phases.

Their only peculiarity was that it was planned from the outset to equip them with the capacity of carriage of single-seater airplanes releasable and in flight. To this end, a hangar was installed inside the dirigibles, in which the aircraft entered through a T-shaped opening made under the envelope. A release and retrieval device was also provided during catapults and stops for maritime aircraft carriers.

The launching and recovery of the aircraft from the airship is carried out with the help of a hook and anchor system, resting on a trapeze. The crews called these pieces of equipment the flying trapezes. The aircraft - usually a biplane - was equipped on its upper wing with a bar for hooking.

For the release, the trapeze hook was engaged on the aircraft support in the airship's hangar. Then the plane was descended by the trapezium and placed in the wake of the dirigible, at a sufficient distance from the envelope. The engine was then switched on and the aircraft could then clear itself from the wake.

For recovery, the biplane had to fly under its airship at a slightly higher speed than the latter. The pilot had to maneuver his apparatus to catch the bar implanted on the upper wing of his apparatus by the hook. He used an approach lateral maneuver to use the tolerance offered by the width of the fastening bar (the device having no margin for maneuver on the vertical axis, more dangerous more enter the aircraft in a collision with the bottom of the envelope of the airship). As soon as the contact between the hook and the bar was obtained, the locking was automatic and the motor had to be cut. The airplane was then lifted by the trapeze and returned to the airship's hangar.

The maneuver was particularly dangerous in wind gusts and even in optimal conditions it was not uncommon for several attempts to be made before the recovery of the aircraft was completed.

Several projects were designed to make Zeppelin airships capable of releasing and fetching fighter jets. There are also many examples of aircraft carriers or lighter aircraft than air in literature and fiction.

The operational airships carrying aircraft are:

• The USS Los Angeles (ZR-3): used as a prototype to test concepts deployed on Akron and Macon. In service from 27 August 1924, removed from service on 24 October 1939
• The USS Akron (ZRS-4): first flight on September 23, 1931, destroyed, with its crew, on April 4, 1933
• The USS Macon (ZRS-5): put into service on June 23, 1933, accident on February 26, 1935

The abandonment of this aeronautical sector after 1935, designed by the US Navy to carry out long-range reconnaissance missions, created a lack in this area until the advent of the radar. Although equipped with radar stations on the Hawaiian Islands, the Admiralty was unable to exploit this new technology5 to identify the Japanese air attack on the morning of 7 December 1941.

Airships are kind of aircraft. Airships stay in the sky by floating. This is different from aeroplanes that stay in the sky by moving. An airship floats like a balloon. But an airship is different from a balloon. An airship has an engine for power and a way to control its direction of movement. A balloon does not have an engine or a way to control its direction of movement.

Some people may use the word "airship" to mean any kind of aircraft. This is not exactly correct. Technical people use the word "airship" only to mean a aircraft that floats and has both an engine and a way to control its direction of movement (Airship, From Wikipedia).

There are three kinds of airships. The difference is the amount of structure in the airship:

• Rigid airships - Rigid airships have big structures in them. The biggest airships were rigid airships made in the 1920s and 1930s. Big rigid airships were also called dirigibles
• Semi-rigid airships - Semi-rigid airships have small structures in them. There are only a few semi-rigid airships
• Non-rigid airships - Non-rigid airships have no structures in them. Non-rigid airships are also called blimps. Most airships are non-rigid airships. Blimps were used by the United States in WWII to fight against submarines. Blimps are now used mostly for advertising

A balloon satellite (also occasionally referred to as a "Satel loon", which is a trademarked name owned by Gilmore Schjeldahl's G.T. Schjeldahl Company) is a satellite that is inflated with gas after it has been put into orbit (Balloon satellite, From Wikipedia).

Pageos was specially launched for the "global network of satellite geodesy", which occupied about 20 full-time observing teams all over the world until 1973.

All together they recorded 3000 usable photographic plates from 46 tracking stations with calibrated all-electronic BC-4 cameras (1:3 / focal length 30 and 45 cm (12 and 18 in)). From these images, they were able to calculate the stations' position three-dimensionally with a precision of about 4 meters (13 ft). The coordinator of this project was Professor H. H. Schmid, from the ETH Zurich.

Three stations of the global network were situated in Europe: Catania in Sicily, Hohenpeißenberg in Bavaria and Tromsø in northern Norway. For the completion of the navigational network, exact distance measurements were needed; these were taken on four continents and across Europe with a precision of 0.5 millimeters (0.020 in) per kilometer.

The global network enabled the calculation of a "geodetic date" (the geocentric position of the measurement system) on different continents, within a few meters. By the early 1970s, reliable values for nearly 100 coefficients of the Earth's gravity field could be calculated.

An espionage balloon is a balloon used for spying (Espionage balloon, From Wikipedia).

During the Cold War, espionage balloons launched by the "Free world" had a secondary psychological warfare capability, carrying propaganda pamphlets and consumer goods (which were supposedly not freely available inside Communist states) that would be released or otherwise delivered onto enemy territories.

The advent of spy satellites, coupled with the end of the Cold War, have rendered espionage balloons obsolete.

Surveillance balloon programs include:

• Project Moby Dick
• Project Genetrix

A surveillance blimp is a type of airborne early warning and control aircraft, typically as the active part of a system which includes a mooring platform, communications and information processing. Example systems include the U.S. JLENS and Israeli Aeronautics Defense Skystar 300 (Surveillance blimp, From Wikipedia).

High-altitude balloons are unmanned balloons, usually filled with helium or hydrogen and rarely methane, that are released into the stratosphere, generally attaining between 18,000 to 37,000 meters (59,000 to 121,000 ft; 11 to 23 mi). In 2002, a balloon named BU60-1 attained 53.0 km (32.9 mi; 173,900 ft).

The most common type of high-altitude balloons are weather balloons (High-altitude balloon, From Wikipedia). Other purposes include use as a platform for experiments in the upper atmosphere. Modern balloons generally contain electronic equipment such as radio transmitters, cameras, or satellite navigation systems, such as GPS receivers.

These balloons are launched into what is termed "near space", the area of Earth's atmosphere where there is very little air, but where the remaining amount generates too much drag for satellites to remain in orbit.

Due to the low cost of GPS and communications equipment, high-altitude ballooning is a popular hobby, with organizations such as UKHAS assisting the development of payloads.

Manned high-altitude balloons were used from the 1930s to 1960s for research and in seeking flight altitude records.

Results

P-791 is an aerodynamic/aerodynamic experiment developed by Lockheed-Martin.

The first flight of P-791 was on January 31, 2006, aboard the aircraft test company, aboard Palmdale 42. It has a unique shape in three boxes with disk buffers at the bottom for landing. A very similar project can be seen in the vehicle of the Multilingual Vehicle (LEMV).

P-791 is an example of a hybrid aircraft. In such drawings, a part of the weight of the craft and its useful load are supported by aerostatic lifting (floating) and the rest is supported by an aerodynamic lift.

 The combination of aerodynamic and aerostatic lifting is an attempt to benefit both from the high speed of aerodynamic craft and the aerostatic lifting capacity. Critics of the hybrid approach have considered it "the worst of both worlds" in that such craft requires a landing and landing track, is difficult to control and protect on the ground and has relatively low aerodynamic performance.

Proponents of hybrid projects argue that these deficiencies can be overcome by advanced technologies. In particular, it has been proposed that the buoyancy control mechanisms reduce or eliminate the need for a runway.

The world's largest airplane, Airlander 10, a combination of airplane, airship, helicopter and airplane, made its first flight Wednesday after months of training and years of research and funding in 2016.

The flight did not take long - just 20 min, landing being a problem, in Cardington, north of London, CNN shows.

His design gave him the nickname '' Flying Ass, '' but the aircraft is ready to show the world what it is capable of.

The way he shows it gave him the name of "Flying Fund". But the biggest flying machine is ready to prove what it is, at the end of this month when it leaves the hangar. Airlander 10 has a length of 92 m and this summer will make six flights to demonstrate its technology.

Hybrid Air Vehicle, the company behind the aircraft, presented details of the routes and maneuvers that will be used to put the hybrid aircraft on its route.

The 92-meter-long aircraft, 26 tall and 43.5 m wide, was due to fly on Sunday, but the time was postponed due to technical problems.

Airlander 10 is a combination of a plane and a dirigible, being 15 m longer than the largest passenger aircraft in the world. It will fly at an altitude of 1,219 m at a speed of 74 km/h.

The aircraft will fly over the Cardington area in the UK. Another test to which Airlander 10 will be placed will be flying 138 km at an altitude of 3048 m at a speed of 111 km/h.

A modern airship can have elegant shapes and can also be designed for pleasure trips.

This is a modern, solid, economic ship, capable of climbing easily at any altitude and additionally capable of increasing its speed to very high values for a dirigible.

Discussion

Stealth aircraft are aircraft that use stealth technology to avoid detection by employing a combination of features to interfere with radar as well as reduce visibility in the infrared, visual, audio, and radio frequency (RF) spectrum. Development of stealth technology likely began in Germany during World War II. Well-known modern examples of stealth aircraft include the United States' F-117 Nighthawk (1981–2008), the B-2 Spirit, the F-22 Raptor, and the F-35 Lightning II.

While no aircraft is totally invisible to radar, stealth aircraft prevent conventional radar from detecting or tracking the aircraft effectively, reducing the odds of a successful attack. Stealth is the combination of passive low observable (LO) features and active emitters such as Low Probability of Intercept Radars, radios and laser designators. These are usually combined with active defenses such as chaff, flares, and ECM. It is accomplished by using a complex design philosophy to reduce the ability of an opponent's sensors to detect, track, or attack the stealth aircraft. This philosophy also takes into account the heat, sound, and other emissions of the aircraft as these can also be used to locate it.

Vertol began work on a new tandem-rotor helicopter designated Vertol Model 107 or V-107 in 1957. In June 1958, the US Army awarded a contract to Vertol for the aircraft under the YHC-1A designation. The YHC-1A had a capacity for 20 troops. Three were tested by the Army to derive engineering and operational data. However, the YHC-1A was considered by most of the Army users to be too heavy for the assault role and too light for the transport role. The decision was made to procure a heavier transport helicopter and at the same time upgrade the UH-1 "Huey" as a tactical troop transport. The YHC-1A would be improved and adopted by the Marines as the CH-46 Sea Knight in 1962. The Army then ordered the larger Model 114 under the designation HC-1B. The pre-production Boeing Vertol YCH-1B made its initial hovering flight on 21 September 1961. In 1962 the HC-1B was redesignated the CH-47A under the 1962 United States Tri-Service aircraft designation system.

The name "Chinook" alludes to the Chinook people of the Pacific Northwest. The CH-47 is powered by two turboshaft engines, mounted on each side of the helicopter's rear end and connected to the rotors by driveshafts. Initial models were fitted with engines of 2,200 horsepower. The counter-rotating rotors eliminate the need for an anti-torque vertical rotor, allowing all power to be used for lift and thrust. The ability to adjust lift in either rotor makes it less sensitive to changes in the center of gravity, important for the cargo lifting role. If one engine fails, the other can drive both rotors. The "sizing" of the Chinook was directly related to the growth of the Huey and the Army's tacticians' insistence that initial air assaults be built around the squad. The Army pushed for both the Huey and the Chinook, and this focus was responsible for the acceleration of its air mobility effort.

Improved and more powerful versions of the CH-47 have been developed since the helicopter entered service. The US Army's first major design leap was the now-common CH-47D, which entered service in 1982. Improvements from the CH-47C included upgraded engines, composite rotor blades, a redesigned cockpit to reduce pilot workload, improved and redundant electrical systems, an advanced flight control system and improved avionics. The latest mainstream generation is the CH-47F, which features several major upgrades to reduce maintenance, digitized flight controls, and is powered by two 4,733-horsepower Honeywell engines.

A commercial model of the Chinook, the Boeing-Vertol Model 234, is used worldwide for logging, construction, fighting forest fires, and supporting petroleum extraction operations. On 15 December 2006, the Columbia Helicopters company of the Salem, Oregon, metropolitan area, purchased the Type Certificate of the Model 234 from Boeing. The Chinook has also been licensed to be built by companies outside of the United States, such as Elicotteri Meridionali (now AgustaWestland) in Italy, Kawasaki in Japan, and a company in the United Kingdom.

The Army finally settled on the larger Chinook as its standard medium transport helicopter and as of February 1966, 161 aircraft had been delivered to the Army. The 1st Cavalry Division had brought their organic Chinook battalion with them when they arrived in 1965 and a separate aviation medium helicopter company, the 147th, had arrived in Vietnam on 29 November 1965. This latter company was initially placed in direct support of the 1st Infantry Division.

The most spectacular mission in Vietnam for the Chinook was the placing of artillery batteries in perilous mountain positions inaccessible by any other means, and then keeping them resupplied with large quantities of ammunition. The 1st Cavalry Division found that its Chinooks were limited to 7,000 pounds payload when operating in the mountains, but could carry an additional 1,000 pounds when operating near the coast. The early Chinook design was limited by its rotor system which did not permit full use of the installed power, and users were anxious for an improved version which would upgrade this system.

As with any new piece of equipment, the Chinook presented a major problem of "customer education". Commanders and crew chiefs had to be constantly alert that eager soldiers did not overload the temptingly large cargo compartment.

It would be some time before troops would be experts at using sling loads.

The Chinook soon proved to be such an invaluable aircraft for artillery movement and heavy logistics that it was seldom used as an assault troop carrier. Some of the Chinook fleet were used for casualty evacuation, due to the very heavy demand for the helicopters they were usually overburdened with wounded. Perhaps the most cost effective use of the Chinook was the recovery of other downed aircraft.

The Chinooks were generally armed with a single 7.62 millimeter M60 machine gun on a pintle mount on either side of the machine for self-defense, with stops fitted to keep the gunners from firing into the rotor blades. Dust filters were also added to improve engine reliability. At its peak employment in Vietnam, there were 22 Chinook units in operation.

Of the nearly 750 Chinooks in the US and Republic of Vietnam fleets, about 200 were lost in combat or wartime operational accidents. US Army supplied Chinooks to the Australian Task Force as required.

During the 1970s, the United States and Iran had a strong relationship, in which the Iranian armed forces began to use many American military aircraft, most notably the F-14 Tomcat, as part of a modernisation programme. After an agreement signed between Boeing and Elicotteri Meridionali, the Imperial Iranian Air Force purchased 20 Elicotteri Meridionali-built CH-47Cs in 1971.

The Imperial Iranian Army Aviation purchased 70 CH-47Cs from Elicotteri Meridionali during the period of 1972–1976. In late 1978, Iran placed an order for an additional 50 helicopters with Elicotteri Meridionali, but that order was canceled immediately after the revolution. Despite the arms embargo on place upon Iran, they have managed to keep their fleet operational.

In the 1978 Iranian Chinook shootdown, four Iranian CH-47C Chinooks penetrated 15–20 km into Soviet airspace in the Turkimenistan Military District. They were intercepted by a MiG-23M which shot down one Chinook, killing eight crew members, and forced a second one to land.

Chinooks were used in efforts by the Imperial Iranian loyalist forces to resist the 1979 Iranian revolution. During the war with Iraq, Iran made heavy use of its US-bought equipment, and lost at least 8 Chinooks during the 1980–1988 period; most notably during a clash on 15 July 1983, where an Iraqi Mirage F-1 destroyed three Iranian CH-47s transporting troops to the front line.

The Chinook was used both by Argentina and the United Kingdom during the Falklands War in 1982. The Argentine Air Force and the Argentine Army deployed four CH-47C (two each) which were widely used in general transport duties.

Of the Army's airframes one was destroyed on ground by a Harrier while the other was captured (and reused after the war) by the British. Both Air Force helicopters returned to Argentina and remained in service until 2002.

Approximately 163 CH-47Ds served in Kuwait and Iraq during Operations Desert Shield and Desert Storm in 1990–91.

The CH-47D has been seen wide use in Operation Enduring Freedom in Afghanistan and Operation Iraqi Freedom in Iraq.

The Chinook is being used in air assault missions, inserting troops into fire bases and later bringing food, water, and ammunition. It is also the casualty evacuation (casevac) aircraft of choice in the British Army.

In today's usage it is typically escorted by attack helicopters such as the AH-64 Apache for protection.

Its tandem rotor design and lift capacity have been found to be particularly useful in the mountainous terrain of Afghanistan where high altitudes and temperatures limit the use of the UH-60 Black Hawk. The CH-47F is being fielded by more units such as the 101st Combat Aviation Brigade and 4th Combat Aviation Brigade in the U.S. Army as it continues to operate in Afghanistan.

The Chinooks of several nations have participated in the Afghanistan War, including aircraft from Britain, Italy, the Netherlands, Spain, Canada, and Australia.

Despite the age of the Chinook, it is still in heavy demand, in part due its proven versatility and ability to operate in demanding environments such as Afghanistan [1-43].

Conclusion

In this paper it is proposed to return to modern airships, equipped with modern technologies, with special flying machines, with special resistant materials, loaded with helium, an inert gas.

Their great advantage is that they can keep themselves alone in the air without high energy consumption, or other devices.

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31. Petrescu, Relly Victoria; Aversa, Raffaella; Akash, Bilal; Corchado, Juan; Berto, Filippo; Apicella, Antonio; Petrescu, Florian Ion Tiberiu; 2017 About Helicopters, Journal of Aircraft and Spacecraft Technology, 1(3):204-223. http://thescipub.com/abstract/10.3844/jastsp.2017.204.223
32. Petrescu, Relly Victoria; Aversa, Raffaella; Akash, Bilal; Berto, Filippo; Apicella, Antonio; Petrescu, Florian Ion Tiberiu; 2017 Forces of a 3R Robot, Journal of Mechatronics and Robotics 1(1):1-14. http://thescipub.com/abstract/10.3844/jmrsp.2017.1.14
33. Petrescu, Relly Victoria; Aversa, Raffaella; Akash, Bilal; Berto, Filippo; Apicella, Antonio; Petrescu, Florian Ion Tiberiu; 2017 Direct Geometry and Cinematic to the MP-3R Systems, Journal of Mechatronics and Robotics 1(1):15-23. http://thescipub.com/abstract/10.3844/jmrsp.2017.15.23

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