omniomni/omni-engineering huggingface dataset:
Basler BT-67. The Basler BT-67 is a utility aircraft produced by Basler Turbo Conversions of Oshkosh, Wisconsin. It is a remanufactured and modified Douglas C-47 Skytrain / Douglas DC-3; the modifications are designed to significantly extend the DC-3's serviceable lifetime.

Design and development
Basler Turbo Conversions was founded in 1990 solely focused on converting existing C-47/DC-3 airframes into the BT-67. Basler configures each new build to the client's specifications. Industries served include cargo, military, cloudseeding, and scientific research. The conversion includes fitting the airframe with new Pratt & Whitney Canada PT6A-67R turboprop engines, lengthening the fuselage, strengthening the airframe, upgrading the avionics, and making modifications to the wing leading edges and wingtips.

Due to the higher fuel consumption of the turbine engines of the BT-67, compared to the original piston designs fitted to the standard DC-3, range on the standard fuel tank, with 45 minute reserve, is reduced from . Basler provides a long-range fuel tank which increases the aircraft range to .

Gunship version
The Basler BT-67 has a gunship version used by the Colombian Aerospace Force  for counterinsurgency operations. The Colombian gunships are equipped with a forward-looking infrared (FLIR) ball, enabling the aircraft to conduct effective nighttime missions.

Operators

Military
 
 Colombian Aerospace Force
 National Police of Colombia 
 
 Salvadoran Air Force
 
 Guatemalan Air Force
 
Malian Air Force
 
 Islamic Air Force of Mauritania
 
 Royal Thai Air Force

Civilian

 Australian Antarctic Division

 ALCI Aviation
 North Star Air
 Kenn Borek Air

 Polar Research Institute of China 

 Alfred Wegener Institute
United Kingdom
Bell Geospace

 United States Forest Service

Future operators

 Argentine Air Force:
On 18 April 2024, the State Department approved a possible sale of  BT-67s intended for the Argentinian Air Force with an est. cost of $143 million, with the main contractor being Basler Turbo Conversions.

Accidents and incidents

As of 2019, a total of 15 BT-67 aircraft have been involved in crashes or other incidents since the 1990s.

Specifications (BT-67)

See also

References

External links

 Basler Turbo Conversions, LLC
 The Antarctic Sun "A Timeless Machine Returns"
 The Antarctic Sun "Modern plane and old history maker are birds of a feather"
 Global article

BT-67
1990s United States civil utility aircraft
Low-wing aircraft
Douglas DC-3
Aircraft first flown in 1990
Twin-turboprop tractor aircraft
Aircraft with retractable conventional landing gear
Permendur. Permendur is a cobalt-iron soft ferromagnetic alloy with equal parts of cobalt and iron which is notable for its high magnetic saturation level.  Its saturation flux density of around 2.4 tesla is the highest of any commercially available metal.  Coupled with its low coercivity and core losses, its high saturation and permeability makes Permendur useful as magnetic cores in transformers, electric generators and other electrical equipment.   The advantage of high saturation in a magnetic core is that it can function at higher magnetic field strengths, so the core can be smaller and lighter for a given magnetic flux and power level.  Permendur is used for magnetic cores and pole pieces in lightweight transformers and electric motors used in aircraft.    The alloy was invented in 1929 by Gustav Elmen at Bell Telephone Laboratories.   Various formulations are sold under different trade names.

Cobalt-iron alloys like permendur have very high Curie temperatures so they can function magnetically at high temperatures at which other ferromagnetic materials lose their magnetic properties.  They are harder and less ductile than many other iron alloys and so are harder to fabricate, but have superior mechanical strength.  Most permendur alloys require heat treatment after fabrication to attain the best magnetic properties.

The most important alloys are 
Permendur 2V (Vanadium Permendur, Permendur 49):  Invented by White and Wahl in 1932, it is approximately 49% cobalt, 49% iron and 2% vanadium.  The vanadium improves ductility and workability.
Supermendur (Hiperco 50): Invented by Gould and Wenny in 1957, it has similar composition to Permendur 49 but is grain-oriented so it has a square hysteresis loop and much lower core losses, for better performance in transformers.  Current formulations include trace amounts of niobium, silicon and manganese to improve cold-forming properties.
The coercivity can be controlled by varying the vanadium concentration.  Equiatomic cobalt-iron alloys with more vanadium than permendur, 2-5%, are called Remendur.  This is a medium-coercivity magnet material which bridges the gap between Permendur and Vicalloy cobalt-iron magnets with 8-15% vanadium.

References

Cobalt alloys
Bristol Biplane Type 'T'. The Bristol Biplane Type 'T', sometimes called the Challenger-Dickson Biplane, was a derivative of the Bristol Boxkite. It was  built in 1911 by the British and Colonial Aeroplane Company and was designed as a cross-country racing aircraft for Maurice Tabuteau.

Development
The Type 'T' was not a development of the Bristol Boxkite but did use some of the experience gained with the Boxkite. It was designed by George Challenger, with the assistance of practical advice from Captain Bertram Dickson, a prominent pilot of the day. It had the same "Farman" configuration as the Boxkite, differing principally in having an enclosed nacelle to house the pilot. The structure bearing the front elevator also differed substantially: the elevator was mounted lower down, level with the lower wing, and the undercarriage skids were continued forward and upwards to form part of the elevator mounting. The rear-mounted twin rudders were balanced, unlike those of the Boxkite. 
The first aircraft  (Bristol No. 45) was built to compete in the 1911 Circuit de l'Europe race, with Maurice Tabuteau as pilot, and was powered by a  Gnome Gamma rotary engine. Tabateau put up a creditable performance, and completed all of the race's nine stages.
 
Four more aircraft were built for 1911 Daily Mail Circuit of Britain Air Race. These differed from the design of No. 45 in having  a modified nacelle and rudders placed further out, away from the slipstream of the engine.
No. 51 was to be flown by Graham Gilmour in the race but he was unable to compete because his licence had been suspended. After the race the aircraft was fitted with a 50 hp Gnome and sold to Gerald Napier but on 2 August 1911 it crashed at Brooklands, killing Napier.
No. 52 had a 70 hp Gnome engine and was flown by Collyns Pizey. 
No. 53 had a 70 hp Gnome engine and was flown by Gordon England, and was  withdrawn with engine problems.
No. 54 had a 60 hp Renault engine and was to be flown by Howard Pixton, who crashed during the race and did not finish.

Maurice Tabuteau also entered the race in the original Type T No. 45 but none of Type Ts finished the race. After the crash of No. 51 none of the Type Ts were flown again. An additional machine, No. 59, was modified by Gordon England as the Challenger-England biplane. One more aircraft, No. 78, was to be fitted with a 100 hp Gnome engine but was never completed.

The Challenger-England biplane
Under the direction of Gordon England one aircraft was later converted to a tractor configuration, powered by a  E.N.V. Type F water-cooled V-8 engine.

Specifications (Type 'T')

See also

References

External links
Bristol Aircraft since 1910 - photograph in Flight 1950

Biplanes
Single-engined pusher aircraft
1910s British civil aircraft
Biplane Type T
Rotary-engined aircraft
Aircraft first flown in 1911
Paul A. Fleury. Paul Aimé Fleury (born July 20, 1939) is an American physicist and academic administrator.  He was the dean of the faculty of engineering at Yale University and is the Frederick W. Beinecke Professor of Engineering and Applied Physics and professor of physics.
 
Fleury was born in Baltimore, Maryland and educated at John Carroll University (B.S, 1960) and MIT (Ph.D., 1965).  Fleury was at AT&T Bell Laboratories from 1970 until 1995 including work at Sandia National Laboratories. Fleury was the dean of the school of engineering at the University of New Mexico from 1996-2000.  He then succeeded D. Allan Bromley as dean of engineering at Yale.  In 2007, he became the director of the Yale Institute for Nanoscience and Quantum Engineering. He kept that position after retiring from the deanship at the end of 2007.

His research has been in experimental condensed matter physics and material science including dynamic aspects of phase transformations and optical spectroscopy.

Fleury was elected a member of the National Academy of Engineering in 1996 for discoveries related to ferroelectric, acoustic, and nonlinear performance of materials, and for management leadership in materials. He is also a member of the National Academy of Sciences and the American Academy of Arts and Sciences and a Fellow of the American Association for the Advancement of Science.  He received the Michelson–Morley Award (1985) and the Frank Isakson prize for optical effects in solids (1992) from the American Physical Society.

References
 "Paul Aimé Fleury." Marquis Who's Who, 2006. Reproduced in Biography Resource Center. Farmington Hills, Mich.: Thomson Gale. 2007.

External links 
 Biography at Yale

Living people
Members of the United States National Academy of Sciences
1939 births
21st-century American physicists
Yale University faculty
Yale School of Engineering & Applied Science faculty
Massachusetts Institute of Technology alumni
Members of the United States National Academy of Engineering
John Carroll University alumni
Fellows of the American Academy of Arts and Sciences
Fellows of the American Association for the Advancement of Science
Sandia National Laboratories people
University of New Mexico faculty
Segmentation contractions. Segmentation contractions (or movements) are a type of intestinal motility.

Unlike peristalsis, which predominates in the esophagus, segmentation contractions occur in the large intestine and small intestine, while predominating in the latter. While peristalsis involves one-way motion in the caudal direction, segmentation contractions move chyme in both directions, which allows greater mixing with the secretions of the intestines.  Segmentation involves contractions of the circular muscles in the digestive tract, while peristalsis involves rhythmic contractions of the longitudinal muscles in the gastrointestinal tract.  Unlike peristalsis, segmentation actually can slow progression of chyme through the system.

External links
 
 Animation at colostate.edu
 

Digestive system
Treyfer. In cryptography, Treyfer is a block cipher/MAC designed in 1997 by Gideon Yuval. Aimed at smart card applications, the algorithm is extremely simple and compact; it can be implemented in just 29 bytes of 8051 machine code.

Treyfer has a rather small key size and block size of 64 bits each. All operations are byte-oriented, and there is a single 8×8-bit S-box. The S-box is left undefined; the implementation can simply use whatever data is available in memory. In each round, each byte has added to it the S-box value of the sum of a key byte and the previous data byte, then it is rotated left one bit. The design attempts to compensate for the simplicity of this round transformation by using 32 rounds.

Due to the simplicity of its key schedule, using the same eight key bytes in each round, Treyfer was one of the first ciphers shown to be susceptible to a slide attack. This cryptanalysis, which is independent of the number of rounds and the choice of S-box, requires 232 known plaintexts and 244 computation time.

Implementation
A simple implementation of Treyfer can be done as follows

#include <stdint.h>

#define NUMROUNDS 32
extern uint8_t const sbox[256];

void treyfer_encrypt(uint8_t * text[8], uint8_t const key[8]) {
    unsigned i;
    uint8_t t = *text[0];

    for (i = 0; i < 8 * NUMROUNDS; i++) {
        t += key[i % 8];
        t = sbox[t] + *text[(i + 1) % 8];
        t = (t << 1) | (t >> 7);        /* Rotate left 1 bit */
        *text[(i + 1) % 8] = t;
    }
}

void encrypt(uint8_t * text[8], uint8_t const key[8]) {
    unsigned int i = 0;
    unsigned int j = 0;
    uint8_t t = 0;

    t = text[0];
    for (j = 0; j < NUMROUNDS; j++) {
        for (i = 0; i < 8; i++) {
            t = t + key[i];
            t = sbox[t] + *text[(i + 1) % 8];
            t = (t << 1) | (t >> 7);
            *text[(i + 1) % 8] = t;
        }
    }
}

void decrypt(uint8_t *text[8], uint8_t const key[8]) {
    int i = 0;
    int j = 0;
    uint8_t top = 0;
    uint8_t bottom = 0;

    for (j = 0; j < NUMROUNDS; j++) {
        for (i = 7; i >= 0; i--) {
            top = *text[i] + key[i];
            top = sbox[top];
            bottom = *text[(i + 1) % 8];
            bottom = (bottom >> 1) | (bottom << 7);
            *text[(i + 1) % 8] = bottom - top;
        }
    }
}

See also

 Tiny Encryption Algorithm

References

 

Broken block ciphers
Developing tank. A developing tank is a light-tight container used for developing film. A developing tank allows photographic film to be developed in a daylight environment. This is necessary because most film is panchromatic and therefore can not be exposed to any light during processing. Depending upon the size and type, a developing tank can hold one to many roll or sheet films.
Famous brands include Paterson, Yankee, Jobo and Nikor.

A film reel holds roll films in a spiral shape. The film is held evenly spaced so that the chemicals in the developing tank reach all of the film.

Types

General
General tank support 110,126,135,120,620 format films
Developing tanks and film reels for roll films come in two varieties: plastic and stainless steel. With stainless steel reels, the film is clipped to the center and then gently pinched while the reel is turned so that the film falls into the reel's grooves. With a plastic reel, the film is loaded from the outside and then wound onto the reel by rotating the reel with a back-and-forth motion.

Special purpose

Minox daylight development tank. Minox format film can be loaded in broad daylight without the use of a changing bag or darkroom.
Meopta 16mm development tank.  Used for 16mm film only.  Film must be loaded in darkroom.
Agfa Rondinax 35 and 60. Respectively used for 135 and 120 film formats. Can be loaded in broad daylight without the use of a changing bag or darkroom.

Use

The user begins by opening the film canister (in the case of 35 mm film) or separating the film from a paper backing (in the case of medium format film, e.g. 120/220 format). The film is then loaded onto a film reel in a completely dark environment; this can be a light-tight room or a changing bag. Care must be taken during this step, as improperly loading the film may result in parts of the film not getting developed. Once the film is on the reel it is put into the developing tank, and then a lid is placed on the developing tank. Because the lid prevents light from reaching the film, the rest of the film developing process may be carried out in daylight. In addition to protecting the film from light, the lid contains an opening for rapidly pouring liquids into and out of the developing tank. Finally, a separate cap seals the canister, which prevents the contents of the tank from spilling when agitated by inverting the tank. But the tank should be cleaned by water every time after development as any residual fixer may not lead to proper development of the next film.

References

External links
 

Photography equipment
Liquid containers
Georges Jean Marie Darrieus. Georges Jean Marie Darrieus (24 September 1888 – 15 July 1979) was a French aeronautical engineer in the 20th century. He invented the Darrieus rotor, a wind turbine capable of operating from any direction and under adverse weather conditions, and the vertical-axis giromill.

The invention is described in the 1931 .

Darrieus is also known for introduction of laminated pressplates into the construction of the stators used in synchronous generators thus reducing the core losses.

Biography
In World War I, Georges Darrieus was appointed as the artillery captain in 1917.

References

Sources

External links
academie-sciences.fr 
US patent 1,835,018

French aerospace engineers
Members of the French Academy of Sciences
20th-century French inventors
Wind turbines
1888 births
1979 deaths
French fluid dynamicists
Canadian Associated Aircraft. Canadian Associated Aircraft was a joint Canadian-United Kingdom project to build Handley Page Hampden aircraft in the late 1930s.

History
During the build-up to the Second World War, Fairchild Aircraft Ltd. had joined together with five other aviation companies in setting up Canadian Associated Aircraft Ltd. The consortium was formed in 1938 to build the Handley Page Hampden for use in the Royal Air Force with Fairchild mainly contracted to build the Hampden's empennage. Of 1,430 Hampdens manufactured, 160 were built in Canada by the "Canadian Associated Aircraft" consortium of three Ontario (Fleet Aircraft, National Steel Car, Ottawa Car and Aircraft) and three Quebec (Canadian Car and Foundry, Fairchild, Canadian Vickers) aircraft companies as a so-called "educational project" to build up the Canadian aircraft industry and provide the expertise for building the four-engined Short Stirling bomber (ultimately the Stirling project was dropped and the Avro Lancaster was substituted).

Production

The Hampden was the only aircraft the consortium produced. They were built at Malton Airport near Toronto and at St. Hubert Airport near Montreal.

Of the 160 Hampdens built, 84 were shipped by sea to Britain, while the remainder came to  Royal Air Force station Patricia Bay (now Victoria Airport), British Columbia to set up No.32 Operational Training Unit (RAF). Due to heavy attrition from accidents, a number of "war weary" Hampdens were later flown from the UK to Patricia Bay as replacements.

Surviving aircraft

Hampden Mk I P5436 was one of the Canadian-built Hampdens. It completed only 100 hours of flying time before crashing near Patricia Bay, on 15 November 1942, while engaged in torpedo dropping practice.  In the 1980s, the Canadian Museum of Flight salvaged the remains of Hampden AN136 from Mt. Tuam on Saltspring Island and, later, N132 from a mountaintop near Ucluelet, British Columbia. Together with the salvage of P5436 in 1985, a lengthy reconstruction project was culminated in the unveiling of the composite P5436 Hampden now on display in the museum.

Facilities

Two facilities that built CAA aircraft:

 Saint Hubert Airport, Saint Hubert, Quebec - taken over by RCAF as RCAF Station St. Hubert beginning in 1941
 Malton, Ontario – National Steel Car, later taken over by government to form Victory Aircraft in 1942

References

Defunct aircraft manufacturers of Canada
Former defence companies of Canada
Tachikawa Ki-94. The Tachikawa Ki-94 was a single-seat fighter-interceptor aircraft project undertaken by the Tachikawa Aircraft Company and to be operated by the Imperial Japanese Army. The project refers to two aircraft designs: the Ki-94-I and the Ki-94-II, both of which did not advance beyond the mock-up and prototype stage respectively.

Design and development

Ki-94-I

The first was a twin-boom monoplane with two  Mitsubishi Ha211 18-cylinder engines, driving two 4-blade propellers in a push-pull configuration. The very heavy armament planned for the aircraft (two  and two  cannon should have been enough to make short work of most US heavy bombers of the era. Notwithstanding the outstanding prospective performance, which however, was judged as "unduly optimistic" by the technical department of the Japanese Army Air Force, this design was judged too complex by the technical department, and the design was discarded.

Ki-94-II
The second Ki-94 design, made by a team also under Tatsuo Hasegawa as type I, chief designer of the aircraft and responsible for the used airfoil, was a more conventional single-seat, piston-engine monoplane fighter developed for the Imperial Japanese Army Air Force along the same requirements as the Nakajima Ki-87, which had been the Army's fall-back design for the original Ki-94. Intended to counter B-29 raids, it was optimized for high-altitude interception with a pressurized cockpit and heavy armament.

This design was approved by the Koku Hombu, and the aircraft was designated Ki-94-II (the scrapped earlier Ki-94 design was named the Ki-94-I). An order was placed for one static test airframe, three prototypes, and eighteen pre-production aircraft. Only two prototypes were built in the event; the first was equipped with a single  Nakajima Ha219 [Ha-44] engine, driving a 4-blade propeller because the 6-blade one was not ready. The second prototype was to be fitted with a 6-blade propeller. The War's end however stopped the construction of the second prototype and also found the first prototype still being readied for its maiden flight. So, the Ki-94-II never took to the air.

Specifications (Ki-94-II (estimated performance))

See also

References

Bibliography

 . First edition from 1970

External links

  Webpage devoted to Tatsuo Hasegawa by his son Akio Hasegawa, MD

1940s Japanese fighter aircraft
1940s Japanese experimental aircraft
Twin-engined push-pull aircraft
Ki-94
Twin-engined piston aircraft
Low-wing aircraft
Twin-boom aircraft
Inverted gull-wing aircraft
Single-engined tractor aircraft
I.Ae. 22 DL. The I.Ae. 22 DL was an Argentine advanced training aircraft designed by the Instituto Aerotécnico (AeroTechnical Institute) in 1943. It had a wooden structure which resembled the North American NA-16.

Development
The I.Ae. 22 DL was a development of the I.Ae. D.L. 21, which was itself developed from the North American NA-16, which was also in service with the Argentine military at that time.

Argentine experience with the NA-16-4P and deteriorating political relations with the US led to the local development of the I.Ae. D.L. 21, which shared the NA-16 fuselage structure. However it proved too difficult to produce and an entirely new design (the I.Ae. D.L. 22) of similar configuration, but structurally different and optimized to available materials was built instead.

It had a wooden structure and a nine-cylinder  I.Ae. 16 El Gaucho radial engine with a Hamilton Standard 2M-D-30 metallic propeller.

The prototype flew on 8 August 1944.  Approximately 200 aircraft were built.  A version with a  Armstrong Siddeley Cheetah 25 radial engine and a Rotol constant speed propeller was designated I.Ae. 22-C.

Operators
 
 Argentine Air Force
 Argentine Naval Aviation

Surviving aircraft

 A restored example, constructor number 728, is on display marked as Ea-701 at the Museo Nacional de Aeronáutica de Argentina.

Specifications (I.Ae.22 DL)

See also

Footnotes

References

Bibliography
 
 Burgos, Antonio C. "Los 75 años de la Fábrica Militar de Aviones"(in Spanish). aeroespacio.com. Retrieved: 15 October 2009. 
"Fabrica Militar de Aviones" (in Spanish). Aerospacio, Buenos Aires, 1977.  Article on the 50th anniversary of the "Fabrica Militar de Aviones" listing all the aircraft developed and manufactured there since 1927.

Further reading

External links

 Development and Specifications (in Spanish)

IAe022
1940s Argentine military trainer aircraft
Single-engined tractor aircraft
Low-wing aircraft
World War II military equipment of Argentina
Aircraft first flown in 1944
Aircraft with retractable conventional landing gear
Single-engined piston aircraft