omniomni/omni-engineering huggingface dataset:
Kreider-Reisner XC-31. The Kreider-Reisner XC-31 or Fairchild XC-31 was an American single-engined monoplane transport aircraft of the 1930s designed and built by Kreider-Reisner. It was one of the last fabric-covered aircraft tested by the U.S. Army Air Corps. Designed as an alternative to the emerging twin-engined transports of the time such as the Douglas DC-2, it was evaluated by the Air Corps at Wright Field, Ohio, under the test designation XC-941, but rejected in favor of all-metal twin-engined designs.

The XC-31 was built with an aluminum alloy framework covered by fabric, and featured strut-braced wing and fully retractable landing gear, with the main gear units mounted on small wing-like stubs and retracting inwards. An additional novel feature was the provision of main cargo doors that were parallel with the ground to facilitate loading.

Following evaluation by the USAAC, the XC-31 was transferred to NACA, which used it for icing studies at its Langley Research Center.

Specifications

See also

References

C-031
1930s United States military transport aircraft
Single-engined tractor aircraft
High-wing aircraft
NASA aircraft
Aircraft first flown in 1934
Aircraft with retractable conventional landing gear
Single-engined piston aircraft
Düsseldorf–Elberfeld railway. The Düsseldorf–Elberfeld railway is a 27 km long main line railway in Germany, originally built by the Düsseldorf-Elberfeld Railway Company, connecting Düsseldorf and Elberfeld (now Wuppertal) via Erkrath, Hochdahl and Vohwinkel.  It is served by Regional Express, Regionalbahn and S-Bahn trains.

History 
The Düsseldorf–Elberfeld railway was built from 1838 to 1841 by the Düsseldorf-Elberfeld Railway Company (Düsseldorf-Elberfelder Eisenbahn-Gesellschaft, DEE), which had been established for this purpose. It was taken over by the Bergisch-Märkische Railway Company (Bergisch-Märkische Eisenbahn-Gesellschaft, BME) in 1857 and a continuous second track was built by 1865.

Realignment of lines in Düsseldorf 

The Düsseldorf Central Station opened on 1 October 1891 replaced the three stations of the recently nationalised, formerly (nominally) private railway companies. The new line from the Düsseldorf station ran north along the existing route of the trunk line of the Cologne-Minden Railway Company to Wehrhahn CME junction. It then swung east and followed the Düsseldorf-Derendorf–Dortmund Süd line of the Rhenish Railway Company. East of the intersection with the Troisdorf–Mülheim-Speldorf freight line it rejoined it original route. The Düsseldorf Valley Railway separates at the same place and runs to the northeast.

Erkrath-Hochdahl incline 

The biggest challenge in the construction of the line was dealing with the climb between Erkrath and Hochdahl. The line has a gradient of 3.33% and rises 82 m in about 2.5 km. For more than one hundred years, this was the steepest main line in Europe. For many years trains had to be hauled by cable, originally driven by a stationary steam engine. A few months later haulage by cable attached to a stationary steam engine was changed to haulage by cable attached via pulleys to a locomotive running downhill on an additional track. With the duplication of the remainder of the line in 1865, the steep section of line became three-track, until the electrification of the line in 1963. The third track was rebuilt in 1985, as part of the additional third track built for the planned S-Bahn line.  In 1926, cable haulage on the incline was replaced by bank engines.

Current situation 

Between Gruiten junction and the Düsseldorf-Gerresheim station the long distance line is only single track. Regional Express lines RE 4 Wupper-Express and RE 13 Maas-Wupper-Express run on this line, stopping only at Düsseldorf, Vohwinkel and Wuppertal. S-Bahn line S 8 services runs on the parallel two-track S-Bahn line.

References 

Railway lines in North Rhine-Westphalia
Railway lines opened in 1838
1838 establishments in Prussia
Buildings and structures in Wuppertal
Buildings and structures in Mettmann (district)
Transport in Düsseldorf
Custer CCW-5. The Custer CCW-5 was a twin-engined, 5-seat aircraft of pusher configuration, which used a channel wing claimed to enable low speed flight and short take-offs. Two CCW-5s flew, eleven years apart, but the type never entered production.

The aircraft was the third and last of a series of Custer Channel Wing designs.

Design and development
In most situations an aircraft's lift comes chiefly from the low pressure generated on the upper surface by the locally enhanced higher air velocity.  This latter may be the result of the movement of the aircraft through the air or, when lift at low air speeds is important for short take-off performance, produced by engine power. The channel wing, the brainchild of  Willard Ray Custer, is an example of the latter, where the air velocity over the upper surface velocity in a U-shaped channel formed out of the wing was increased with a pusher propeller at the trailing edge. This near semi-circular channel laterally constrained the airflow produced by the propeller, even when the aircraft was at rest, producing higher flow velocities than over a conventional pusher wing. The need for wing mounted pusher engines made a pusher twin a natural configuration, and for his third channel wing design Custer chose to modify the existing Baumann Brigadier, a 5-seat mid wing pusher twin which itself did not reach production.

The CCW-5 retained the fuselage and empennage of the Brigadier, but replaced the whole center section with a pair of channels, starting at roots in the lower part of the fuselage. Only beyond the channels did the conventional wings regain their mid-wing configuration. A  Continental O-470 flat six engine was mounted on slender vertical and horizontal struts at the center of each the channels, on the mid-wing line. These drove constant speed pusher propellers. The main undercarriage was much shortened by mounting its legs on the outer part of the channel section; the Brigadier nosewheel was retained.

The first of two CCW-5s flew on 13 July 1953 and was piloted by Walker Davidson at Oxnard, California. It was reported to have completed its test flying by autumn 1956, when production was scheduled to begin.  This did not happen, though a second aircraft flew in June 1964.  The delay was partly the result of financial problems. The CCW-5 performed well below the original estimates with a maximum achieved speed of  compared with an estimated .  It was claimed that the aircraft could fly under control at  and that it could take off with a  load at 70% power in .

The second CCW-5 was finished in 1964 with  Continental IO-470P engines; it survives and is under restoration at the Mid-Atlantic Air Museum, Reading, Pennsylvania.

Specifications

See also

Notes

References

Channel-wing aircraft
CCW-5
1950s United States civil utility aircraft
Twin-engined pusher aircraft
Aircraft first flown in 1953
Aerospace Industries Organization. Aerospace Industries Organization (AIO, ) is a subordinate of the Iranian defence ministry and a leading high-tech complex headquartered in Tehran. It is a key player in development and production of space assets of Iran, and has some research center and factory under its control. Shahab ballistic missiles are one of notable products manufactured by the organization.

References 

Manufacturing companies based in Tehran
Government-owned companies of Iran
Aerospace companies of Iran
Ministry of Defence and Armed Forces Logistics of the Islamic Republic of Iran
Düsseldorf-Elberfeld Railway Company. The Düsseldorf-Elberfeld Railway Company (German: Düsseldorf-Elberfelder Eisenbahn-Gesellschaft, DEE) was founded in October 1835 and officially recognised by a Prussian government statute on 23 September 1837. This gave the company a concession for the construction and operation of the 26 kilometre long Düsseldorf–Elberfeld line via Erkrath, Hochdahl and Vohwinkel. One of the founders was the Elberfeld banker and later Prussian Minister of Commerce and Industry, August von der Heydt (1801–1874).

Construction
The construction of the first section from Düsseldorf to Erkrath (8.12 km) began on 9 April 1838 and it was opened for freight traffic on 20 December 1838. It was the first steam railway in western Germany (except for the short and sometimes horse-hauled Bavarian Ludwig Railway), the first in Prussia and the fifth in Germany. The Düsseldorf station was originally located at the south end of Königsallee rather than at the current Central Station.

The next section of the line from Erkrath to (Wuppertal) Vohwinkel (12.61 km) was put into operation for freight on 10 April 1841. The opening of the remaining 5.45 km to Steinbeck station in Elberfeld (now part of Wuppertal) followed on 3 September 1841, also only for freight. Passenger operations on the line started on 1 December 1841.

Erkrath–Hochdahl incline
The biggest challenge in the construction of the line was dealing with the climb between Erkrath and Hochdahl.  Because of the steep slope (1 in 30 (3.3%)) in this section for a long time trains had to be hauled by cable, originally driven by a stationary steam engine.  A few months later haulage by cable attached to a stationary steam engine was changed to haulage by cable attached via pulleys to a locomotive running downhill on an additional track.  In 1926, cable haulage on the incline was replaced by bank engines.

Takeover 
During its existence the DEE only operated its original line. After the Bergisch-Märkische Railway Company (BME) was established on 18 October 1843 and which was also based in Elberfeld, the two companies worked closely together. The BME acquired the property of the DEE and its operating rights on 22 September 1856.

External links
Company memorandum ("Denkschrift über die Anlage einer Eisenbahn zwischen Düsseldorf und Elberfeld : mit Beifügung des veränderten Entwurfs des Status und anderer Actenstücke, so wie des Gutachtens des Civil-Ingenieuers Rob. Stephenson in London und mit einer Situations-Karte"), including engineering advice of Robert Stephenson. Published: Düsseldorf, 1837. Digital copy (PDF) in library of  Heinrich Heine University Düsseldorf. 

Defunct railway companies of Germany
IsraGrid. IsraGrid is Israel's national infrastructure for grid and cloud computing. It began operation in January 2009.

A cooperation between Israel's Ministry of Industry, Trade and Employment and the Israeli Science Academy led to the establishment of IsraGrid, operating as a project of the National Infrastructures for R&D Forum (TELEM).

The main objective of IsraGrid is to create an infrastructure for R&D taking advantage of Grid and Cloud Computing. IsraGrid is addressing the needs of all R&D entities, including R&D and IT within enterprises, mature and global Hi-Tech companies and start-ups in different stages with a need for technology ramp-up and need to reduce capital and operational expenses. IsraGrid intends to provide Grid and Cloud infrastructure for R&D in the Israeli academy and industry, and enlarge the computing resources and their efficient usage by organizations and institutions.

References

External links
 IsraGrid (official web site)

Telecommunications in Israel
Tom McDermott (engineer). Tom McDermott is the Deputy Director of the Systems Engineering Research Center at Stevens Institute of Technology, a position he has held since March 2018.

Early life and education
McDermott attended the Georgia Institute of Technology, where he received a Bachelor of Science in physics in 1982, and a Master of Science in electrical engineering in 1984. While at Georgia Tech, he played drums in the Georgia Tech Yellow Jacket Marching Band.

Career

Lockheed Martin
On graduation, McDermott joined the nearby Lockheed Martin Aeronautical Systems in Marietta, Georgia where he would eventually be chief engineer and program manager for Lockheed Martin's F-22 Raptor Avionics Team. McDermott worked for Lockheed Martin from 1984 to 2002.

Georgia Tech
In 2002, McDermott joined the Georgia Tech Research Institute's Electronic Systems Laboratory, where he assumed control of their largest contract, the C-130 Avionics Modernization Program (AMP). In 2006, McDermott was promoted to Director of the Electronic Systems Laboratory.

While at Georgia Tech, McDermott was involved in the creation of a new professional master's degree program in systems engineering, a collaboration between GTRI and the College of Engineering. He taught short courses on topics including electronic warfare principles, systems engineering team leadership, and earned value principles.

In September 2007, McDermott was named Deputy Director and Director of Research of GTRI, where he oversaw GTRI's research agenda, its seven research labs, field offices, and new operations in Athlone, Ireland. He held both positions through August 2013, during which time he was Interim Director of GTRI between Stephen E. Cross's start as Executive Vice President for Research on May 1, 2010, and the placement of former GTRI director Robert McGrath on February 1, 2011.

Stevens Institute of Technology 
McDermott is currently the Deputy Director of the Systems Engineering Research Center (SERC) at Stevens Institute of Technology. He works in multiple technology fields but focuses both his research and teachings in systems engineering areas, including the importance of leadership in engineering. His current research includes "innovation models, strategic foresight techniques, system data analytics, and modeling and simulation of policy implications in current and future complex systems," and he aims to continue his research by looking into developing technology to aid in more rapid systems development and learning.

References

Living people
Georgia Tech alumni
Georgia Tech Research Institute people
People from Atlanta
Year of birth missing (living people)
Civil Aviation Department RG-1 Rohini. The Civil Aviation Department RG-1 Rohini (Literally means Tropic Bird) is an Indian two-seat training sailplane of the 1960s.  A high-winged wooden monoplane, with side-by-side seating;at least 107 were built.

Development and design

The Technical Centre of the Indian Civil Aviation Department is its research and development arm, and started design and production of sailplanes in 1950.  In the early 1960s  S Ramamritham  designed a two-seat training sailplane, the RG-1 Rohini, the first of four prototypes flying on 10 May 1961. The Rohini is a  monoplane of wooden construction, with a braced high wing and a low mounted tail positioned forward of the fin.  Its crew of two sit side by side in an open cockpit, while the aircraft's undercarriage consists of a single  unsprung wheel under the fuselage, with skids under the nose and tail.

A total of 17 Rohinis were built by Veegal Engines and Engineering of Calcutta, with Hindustan Aeronautics Limited building a further 86 RG-1s by 1971.

Specifications (RG-1 Rohini)

See also

Notes

References

HAL aircraft
1960s Indian sailplanes
Civil Aviation Department aircraft
Aircraft first flown in 1961
Waco Aristocraft. The Waco Model W Aristocraft was an American four-seat monoplane, the last aircraft designed and built by the Waco Aircraft Company. It had an unusual configuration with an engine mounted at the front driving a pusher propeller at the rear.

Design and development
The Aristocraft was an attempt by Waco to enter the post-war market for light aircraft. The prototype first flew in March 1947 powered by a  Franklin 6AL piston engine mounted at the front with a shaft driven pusher propeller at the rear. Of all-metal construction it was a high-wing monoplane with twin fins and rudders, It had a partially retractable tricycle landing gear.

The company had orders for 300 aircraft but decided that the type would need costly development in a shrinking market and only the prototype was completed. Waco sold the design rights and in the 1960s efforts were made to market the type for home-construction.

The sole prototype was eventually purchased in the early 1960s and restored to flight.

Specifications

See also

References

Notes

Bibliography

1940s United States civil utility aircraft
Aristocraft
Single-engined pusher aircraft
Mid-engined aircraft
Aircraft first flown in 1947
1992 Azerbaijani Mil Mi-8 shootdown. On January 28, 1992, Azerbaijani transport helicopter Mil Mi-8 was shot down by a heat-seeking missile near the town of Shusha.

The 1993 report by U.S. Federal Aviation Administration on aviation security called it the "most significant incident" involving civil aviation in Central Eurasia.

Background
Serious air warfare during the Nagorno-Karabakh War broke out in January 1992. Azeri aircraft became easy targets for Armenian armed forces. On January 9, the Armenians first claimed to have shot down an Azeri helicopter. More claims followed on January 24, 28 and 31 – all of them over Nagorno-Karabakh, the last being a Mi-8 downed from MANPADs over the village of Huha. On January 31, the Azeris claimed the downings of two Mi-8s that supported the first Armenian offensive.

Shootdown
The Mi-8 helicopter transported 44 persons aboard (41 passengers, all civilians, and 3 crew) when it departed the town of Aghdam for Shusha, which was blockaded by Armenians. The craft was downed en route by a surface-to-air missile. All aboard were killed. According to Azeri journalist Kerim Kerimli, who assisted in collecting bodies at the site and confirmed the number of fatalities, the missile was launched from Xankəndi.

Armenian officials stated that the helicopter was carrying weapons and ammunition to Azeris attacking Armenian villages.

See also

List of aircraft shootdowns during the Nagorno-Karabakh Conflict

References

Accidents and incidents involving the Mil Mi-8
1992 in Azerbaijan
Military operations of the First Nagorno-Karabakh War
Aviation accidents and incidents in Azerbaijan
20th-century aircraft shootdown incidents
Aviation accidents and incidents in 1992
January 1992 events in Asia
Aircraft shootdown incidents in the Nagorno-Karabakh conflict
Galilean cannon. A Galilean cannon is a device that demonstrates conservation of linear momentum. It comprises a stack of balls, starting with a large, heavy ball at the base of the stack and progresses up to a small, lightweight ball at the top. The basic idea is that this stack of balls can be dropped to the ground and almost all of the kinetic energy in the lower balls will be transferred to the topmost ball - which will rebound to many times the height from which it was dropped. At first sight, the behavior seems highly counter-intuitive, but in fact is precisely what conservation of momentum predicts. The principal difficulty is in keeping the configuration of the balls stable during the initial drop. Early descriptions involve some sort of glue/tape, tube, or net to align the balls.

A modern version of the Galilean cannon was sold by Edmund Scientific Corporation and is still sold as the "Astro Blaster". In this device, a heavy wire is threaded through all of the balls to keep them accurately aligned - but the principle is the same. The resulting rebound is quite powerful; in fact, eye safety issues became so prevalent that this toy now comes with safety goggles.

It is possible to demonstrate the principle more simply with just two balls, such as a basketball and a tennis ball. If an experimenter balances the tennis ball on top of the basketball and drops the pair to the ground, the tennis ball will rebound to many times the height from which it was released.

Calculation for two balls

Assuming elastic collisions, uniform gravity, no air resistance and the sizes of the balls being negligible compared to the heights from which they are dropped, formulas for conservation of momentum and kinetic energy can be used to calculate the speed and heights of rebound of the small ball:

 .

Solving the simultaneous equations above for v2′,

Taking velocities upwards as positive, as the balls fall from the same height and the large ball rebounds off the floor with the same speed, v1 = −v2 (the negative sign denoting the direction reversed). Thus

 .
Because .
As the rebound height is linearly proportional to the square of the launch speed, the maximum rebound height for a two-ball cannon is 32 = 9 times the original drop height, when m1 >> m2.

See also 
 Newton's cradle

References

Physics experiments
Educational toys
Jan Paweł Nowacki. Jan Paweł Nowacki (25 June 1905, in Berlin – 23 May 1979, in Warsaw) was an engineer. He worked for the British during World War II on radar installations, and later had a career as a university lecturer.

Biography
He attended secondary school in Berlin. From 1919 he lived in Poznań, where he received his high school diploma. He graduated in 1929 in Lwów with a degree in electrical engineering. In 1928 he was appointed assistant professor to Kazimierz Idaszewski. He earned his PhD in 1937. At the same time he directed various technical projects, such as the electrification of the Warsaw railway junction.

In 1940 he went to France and later to England. He has considerable achievements in development of radar equipment for the British military aviation. He was also a colonel of Royal Air Force authorized to military top secrets.

In 1947 he went to Wrocław to replace Professor Kazimierz Idaszewski in the position of Head of the Department of Electrical Machines. He inspired his colleagues and students to create a School of Electrical Engineering Science. In 1953 he moved permanently to Warsaw, to lead the Chair of Theoretical Electrical Engineering, and later the Department of Nuclear Energy. At the same time he worked in the automation field, and in biocybernetic issues.

The Royal Swedish Academy of Engineering Sciences appointed him as member in 1961. He was also a member of the Polish Academy of Sciences.

References
 http://apw.ee.pw.edu.pl/tresc/sylw/nowacki/nowacki-zycior.htm

20th-century Polish engineers
Members of the Royal Swedish Academy of Engineering Sciences
1905 births
1974 deaths
Structural fracture mechanics. Structural fracture mechanics is the field of structural engineering concerned with the study of load-carrying structures that includes one or several failed or damaged components. It uses methods of analytical solid mechanics, structural engineering, safety engineering, probability theory, and catastrophe theory to calculate the load and stress in the structural components and analyze the safety of a damaged structure. 

There is a direct analogy between fracture mechanics of solid and structural fracture mechanics: 

There are different causes of the first component failure: 
 mechanical overload, fatigue (material), unpredicted scenario, etc.  
 “human intervention” like unprofessional behavior or a terrorist attack.

There are two typical scenarios: 

A localized failure does NOT cause immediate collapse of the entire structure.
The entire structure fails immediately after one of its components fails.

If the structure does not collapse immediately there is a limited period of time until the catastrophic structural failure of the entire structure. There is a critical number of structural elements that defines whether the system has reserve ability or not. 

Safety engineers use the failure of the first component as an indicator and try to intervene during the given period of time to avoid the catastrophe of the entire structure. For example, “Leak-Before-Break” methodology means that a leak will be discovered prior to a catastrophic failure of the entire piping system occurring in service. It has been applied to pressure vessels, nuclear piping, gas and oil pipelines, etc.

The methods of structural fracture mechanics are used as checking calculations to estimate sensitivity of a structure to its component failure. 

The failure of a complex system with parallel redundancy can be estimated based on probabilistic properties of the system elements.

See also

References

Structural engineering
Continuum mechanics
Fracture mechanics
Solid mechanics