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Rupak Chattopadhyay

@RupakChatto

Jul 23

Now that it is going to be curtains on the @IAF_MCC MiG-21s after 60+ years of service, it is worth remembering that no other type served in the numbers and variants as the MiG-21. Over the years, no fewer than twenty four operational squadrons and four training establishments operated 840+ aircraft of the type.

The first MiG-21 type to join the IAF in 1963 were six MiG-21 F-13 Type 74, followed in 1965 by six MiG-21 PF Type 76.

In 1966, based on its experience from the war in 1965, ordered more MiG-21s. This time the much improved MiG-21 FL, Type -77 variant. 38 aircarft were delivered from the USSR and another 197 were manufactured by @HAL_india between 1966-73. The MiG-21FL (Type 77) and MiG-21PF (Type 76) are visually distinguishable by several key features. The FL variant has a larger tail fin with a brake parachute housing at its base, while the PF's brake parachute is housed in a ventral fairing. The FL also features a detachable gun pod (GP-9) and a larger fuel capacity compared to the PF. The GP-9 was a specific requirement articulated by the IAF based on its 1971 experience. The Type-77 also offered multirole capability in being able to deliver 500kg bombs. The aircraft would be retrofitted after 1982 with additional underwing pylons.

Begining in 1973, the IAF began inducting an upgraded variant in the form of 34 MiG-21MF and 160 MiG-21M fighters. The former were directly supply from the USSR with the R-13 engine a built-in GSh-23L cannon freeing up the centre pylon for a droptank. The M used a modified R-11 engine which was already under manufacturing for the Type-77. Collectively known as the Type-96, the M/MF aircraft offered zero-speed, zero-altitude ejection seat , 4 wing pylons, newer avionics and more fuel. Visually it was distinguished from its predecessors by its thicker spine. The Type-96s would all be upgraded in 2001-04 with a the more modern R-13 engines.

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Rupak Chattopadhyay

@RupakChatto

Jun 27

Thanks to Kapil Chandni and the @indiannavy for their document on the building of the carrier INS Vikrant. It has some interesting information on how the design evolved over almost a two decade period between 1980 and final sanction in 1999. Here is this story. 1/n

In 1980, the Directorate of Naval Design (DND) prepared a concept design of a ‘Helicopter Carrier’ based on the hull form of MV Harshavardhan, a merchant vessel .

This was followed by in 1985 a formulation of Outline Staff Requirements (OSRs) a Sea Control Ship (SCS) of 35,000 ton.

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Rupak Chattopadhyay

@RupakChatto

Feb 7

Purnima Sinha (1927 – 2015) was a physicist and one of the first Bengali women to earn a doctorate in physics in the field of x-ray crystallography of clay minerals. She was born to Dr. Nares Chandra Sengupta, a constitutional lawyer and progressive writer. She married the anthropologist Surajit Chandra Sinha, later vice-chancellor, Visva-Bharati University.

After obtaining her MSc degree in Physics from Calcutta University, she joined for her PhD work in 1951 under the legendary physicist Satyendra Nath Bose. Purchase of equipment in the early years of independence was difficult and she built instruments with components available in the open market. She recalled “we had put together our X-ray equipment from the World War II surplus gathered in the lane behind Dr Bidhan Roy’s house”. Purnima’s PhD research was entitled “X-ray & Differential Thermal Analysis of Indian Clays”. She also worked with Nobel Laureate physicist Paul M Dirac when he was a visitor to Calcutta University in 1954.

In the early 1960s, Purnima worked on the origin of life with clay as the substrate in the Biophysics Group at Stanford University, California. She observed that the spacing in the clay structure, determined through X-ray studies, corresponded to the pitch of the DNA double helix. Since then, she remained interested in biophysics till the end of her life. After her return from the USA in 1964 she spent most of her professional life at the CGCRI, Kolkata till she took voluntary retirement in 1986.

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Rupak Chattopadhyay

@RupakChatto

Jan 6

Pafulla Chandra Roy (1861 – 16 June 1944) was an Indian chemist, educationist, historian, industrialist and philanthropist. A product of the Bengali Renaissance, he was the founder of Bengal Chemicals & Pharmaceuticals, India's first pharmaceutical company. He is the author of A History of Hindu Chemistry from the Earliest Times to the Middle of the Sixteenth Century (1902).

The book draws uses primary sources to deal with a ranage of subjects inlcuding, metallury and rare-earths extraction. Topis include Colophon - The Rasas - Abhra - Vaikranta -copper Pyrites Vimala - Silajatu - Sasyaka - Extraction of Copper - Chapala Rasaka - Extraction of Zinc - The Uparasas or Inferior Rasas Sulphur Gairika Kasisa Tuvari Talaka Manassila - The Afijanas - The Common Rasas - Navasara and other Rasas - The Gems - Vajram - General Process of Reducing Gems to Ashes - On Metals - Gold - Silver - Copper - I on - Tin - Lead Brass - Bell Metal, &c. - Initiation into Discipleship - On the Laboratory - Tests for Killed Iron - Antimony

Prafulla Babu was born in the village of Raruli-Katipara, then in Jessore District (now Dighalia, Khulna), and was the third child and son of Harish Chandra Raychowdhury. Ray's great-grandfather Maniklal had been a dewan under the British East India Company's district collector of Krishnanagar and Jessore. The ruins of the Ray Bari still exist.

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Rupak Chattopadhyay

@RupakChatto

Mar 28, 2023

Meet Nelson Wang, the inventor of Indian-Chinese the "Chicken Manchurian". Wang was born in Calcutta's Tangra China Town in 1950. When his family moved to Canada in the 1977, Nelson decided to move to Bombay.
#ChickenManchurian #Chinese #Cricket #Foodie

Strating out as a nightclub limbo dancer and fire-eater, he found a job was as a cook at Frederick's, a Chinese restaurant in Colaba and where the legendary Raj Singh Dungarpur, then President of the Cricket Club of India was a regular.

Frederick's was asked if could cater to Cricket Club of India, but turned down the offer. So Nelson took on the challenge. It was here that Dungarpur, who liked fried food asked Nelson for something spicy and crunchy with a gravy.

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Rupak Chattopadhyay

@RupakChatto

Mar 27, 2023

INS Kamorta P177, later P77 was the first Peyta ASW ship commissioned into the Indian Navy on21 November 1968. In 1971 she served in the Eastern fleet as part of its ASW screen and intercepted blockade runners. She was decomissioned in 1991.

@OfficialGRSE

INS Kamorta P28 is the leadship of the Project-28 ASW corvettes built by @OfficialGRSE and commissioned in 2014. He is armed with OTO Melara SRGM, AK-630M CIWS, RBU-6000 and Torpedo tubes. She will be oufitted with a 50km VL SRSAM from DRDO.

@ThingsNavy

@ThingsNavy @IndianShips

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