Tejas LCA SP-21: Final Operational Clearance

Light Combat Aircraft [LCA] SP-21 with Final Operational Clearance[FOC] finally took to the sky. When a fighter jet is given FOC it means that it has satisfied all the minimum requirement set to it by it’s consumer[IAF] and it is also combat worthy now.

LCA SP-21 about to take off.

It is good to know that LCA with FOC finally took to the sky. It is important to remember that making a modern fighter jet is extremely challenging. Only a handful of nations can claim to develop a fighter jet. Though LCA mk1 is not very cutting edge in the present scenario but it can totally replace MiG-21 which are just too dangerous to fly due to old age. This FOC configuration, that is LCA mk1 will be produced in small number that is a total of 16. Air force has further added 83 orders but for LCA mk1A, which will be much more advanced compared to this LCA mk1 and will take another 3 to 4 years to get into production.

Features added in LCA SP-21

  • Air to Air refueling, you can see refueling probe on the nose of the Aircraft.
  • Beyond Visual Range(BVR) Missile system.
  • Manufacturing improvements.
  • Option to add additional fuel drop tank.

As of now LCA Tejas is not deployed along the border with Pakistan and China but it would be proud day to see LCA Tejas defending the borders one fine day and replace MiG-21s . China has advance Air Force and LCA will be need in larger number to counter them.

Even though it took decades for LCA to become combat ready, it has provided industries valuable lesson and this will result in faster roll out of more advanced LCA mark-1A and LCA mark-2. India is a developing country and cannot afford to waste a lot of money on defence. A modern fighter jet costs around 500 crore rupees, that is hell lot of money and that is why it is very important that we get this thing made in India. I was not sure earlier but now I think Indian industry is in the right direction and I am looking forward to one day see a huge number of Indian fighter jet in Indian Air Force.

As of now a total of 123 LCA fighter jets have been ordered. This decision has been taken mostly to keep this Fighter program rolling, which is something necessary. Also there needs to large participation from private players in defense industry else things can go bad.

Rafale fighter jet of Indian Air Force

India finally purchased Rafale fighter jet after a lot of confusion. It is a fighter jet developed by France in 1980s to replace Mirage 2000. Rafale is a advanced 4th generation fighter jet. India which is struggling to develop LCA and which lacks power to take in battle field had to go for This fighter jet. India has air superiority Su-30 aircraft but Mig-21, Mirage 2000 are all getting old and have to be replaced.

Rafale fighter jet of French Air Force.
Rafale fighter jet of French Air Force.

Rafale is twin engine, multi-role aircraft which can be used for Air to Air or air to ground attacks. One Rafale costs almost 600 crore Indian rupees. It has a maximum speed of 1920 km/hr and combat range of 1850 kilometers. It has empty weight of 10330 kilograms which makes it a medium weight fighter jet. This jet can carry 10 tons of weapons. Also there is a Naval version of Rafale jet which India may consider in future. Rafale is also used by Egyptian Air Force and Qatar Air Force. Great

India has placed an order of 36 Rafale jets and it looks like a lot more will be added in near future. In 2019 fight between India and Pakistan, India lost 1 Mig-21 and an Indian pilot was captured by Pakistan. If India had Rafale, it would have been a different matter during this little fight. India also has China as it’s other adversary and Rafale will help counter the big Chinese Air Force.

This Jet is expected to serve Indian Air Force for Next 20 to 30 years that is upto 2050. India is also trying to develop a twin engine LCA but it will take upto 10 years to develop and till then Rafale will help India in defending it’s border.

January current affair for NDA I 2020.

Important current affair or events which happened in January 2020 for NDA I 2020 Examination.

1. National Voter’s Day: 25th January.
“Electoral Literacy for Stronger Democracy ”was the theme for National Voter’s Day 2020. It was observed that young people were not taking interest in voting, hence government in 2011 decided to celebrate this day to increase interest of people specifically young people in voting. Election commission of India, the body responsible for conducting elections in India was set up on 25th January 2050.

2. 2020 Republic Day chief Guest.
President of Brazil Jair Bolsonaro was the chief guest of 2020 republic day. He was on a 4 day visit to India.

3. Novel Coronavirus
Cornovirus are a type of virus which causes cold, respiratory problems in Human and other animals. There is no vaccine for this virus.
Primary mode of transfer for this disease from Human to Human is through coughing or sneezing. So wearing a breathing mask is recommend. It is believe that this disease was initially transferred from an animal to a human. In Wuhan area of China this virus has killed hundreds of people since December 2019.

4. Khelo India 2020
Khelo India is an initiative by Indian government to promote sports and find new talent in youngsters. Khelo India takes in under two age categories, that is under 17 and under 21. Khelo India 2020 was held from 20 January 2020 to 22 January 2020 in Guwahati, Assam. Maharashtra won the maximum number of gold medals[256], followed by Haryana[200], Delhi[122].

5. 50th World Economic Forum
50th World economic forum was held from 21 to 24 January in Davos, Switzerland. Theme for this years meeting will be “Stakeholders for a Cohesive and Sustainable World”.
The key areas that will be discussed are Ecology, Economy, Technology, Society, Geopolitics, Industry. With increasing climate change and global warming, business around the world are trying to become more environmentally sustainable.Earlier profit was the sole purpose of business which led to large destruction of environment.

6. K-4 ballistic missile.
Final development trial of K-4 ballistic missile was conducted in January 2020.
K-4 is a submarine launched ballistic missile. This missile will be added to Arihant class nuclear submarine and has a range of 3500 kilometers. Nuclear missile submarine has a lot of advantages as these missiles can be launched from any position in the ocean. Also Submarines are less likely to be detected by the enemy so in case of war enemy will not be able to destroy missiles in preemptive strike.

Please click the following given link in order to download or open in PDF format January 2020 NDA I current affair PDF file.

Naval LCA Tejas

LCA Naval MK1 did its first ever landing on INS Vikramaditya which is an Air Craft carrier of Indian Navy. Commodore Jaideep Maolankar was the pilot who landed the light combat aircraft(LCA) on the aircraft carrier.

LCA mk-1 on INS Vikramaditya

Countries such as as Russia, China, USA and France already have the capability of arrested landing of aircraft on aircraft carriers and it goes as far as 50 years back.

Naval LCA was derived from Air Force version of LCA. LCA was made structurally stronger to land on an Aircraft carrier because while landing and stopping over a short distance puts a lot of stress on the structure of the aircraft.

Development of Naval LCA started in 2012, initially it was found to be overweight and under powered to land on an Aircraft carrier and was likely to be scrapped. Over the course of eight year it has been changed and modified into the version known as LCA(N) mk-1 which successfully landed on 11 January 2020 on INS Vikramaditya .

Even though LCA(N) mk-1 has successfully landed on the aircraft carrier, it is still considered to be an experimental aircraft meaning it will be not be inducted in large number in Indian Navy. Indian Navy still considers it to be under powered and short range to take on real world situations and Indian Navy is looking for a two engine variant of LCA(N) Mk-1 which will be called as LCA MK-2 or some other two engine aircraft.

LCA Mk-2 may take upto 10 years to develop and that is a very long time. Still landing of LCA on Vikramaditya has been a great achievement and kudos to all the scientists and engineering who worked on it.

December current affair for CDS I 2020

1. MiG-27 retired from service:

MiG-27 also called as Bahadur was retired from Indian Air Force service on 27th December. MiG-27 is a ground-attack aircraft. It played a major role in Kargil war where it targeted enemy location in Kargil.

2. National Mathematics Day: 22 December.

This day is celebrated is celebrated as National Mathematical Day of India in remembrance of Srinivasa Ramanujan, he is one of the greatest mathematician from India.

3. Vijay Diwas: 16th December.

Vijay Diwas is celebrated on 16th December to remember the victory of India over Pakistan in 1971 war. East Pakistan was liberated which led to creation of a new country called Bangladesh.

4. Chief of Defence staff

General Bipin Rawat was appointed the first Chief of Defence staff on this day. This post has been created to make sure that all three services that is Navy, Air Force and Army work as one structure and can coordinate easily.

5. INDIRA 2019

This was a tri services exercise which took place between India and Russia. This exercise involved all the three services(i.s Navy, Army and Air Force) of both the countries. This exercise took place in Babina, Pune and Goa and it started on 10th December and concluded on 19th December.

6. Hand-In-Hand 2019

Hand-In-Hand is a military exercise which took place between Indian and Chinese armies, this exercise took place in Meghalaya and it started on 7th December.

Fastest fighter jet of Indian Air Force .

MiG-25 developed by Mikoyan of USSR was the fastest jet to ever join Indian Air Force . It had speed of more than 3000 km per hour or over 2.8 Mach. Infact to this date no other aircraft has been build faster than Mig-25 in this category.

USSR MiG-25 in flight.

Indian Air Force bought MiG-25 in 1981. Though it was kept as secret and only 8 were purchased. In India MiG-25 was called as “Garuda”. These jets were mostly used for reconnaissance over Pakistani airspace and Himalaya region, it was also used in Kargil war of 1999. These MiG-25 could fly above 20000 meters height and no aircraft could get close to that height at that time. So taking taking pictures of enemy area was the primary role of this aircraft.

MiG-25 was originally developed around 1961 in USSR to intercept fighter jets of United States. USSR had huge area to protect and hence they needed an aircraft which could fly fast and fly far. MiG-25 was technological marvel of its time. Russia retired Mig-25 in 2010 as it was replaced by its successor MiG-31.

Mig-25 remained in Indian Air Force from 1981 to 2006. Due to availability of spy satellite and heavy cost of maintenance of this aircraft it was deemed fit to be retired. It served India for 25 glorious years.

Important Maths formula for CDSE

Below are some of the important formulas which will help you in CDSE, only a couple of topics have been covered in this post. Time limit in CDSE is less so the better you know the formulas the faster you will be able to solve your paper.


  1. log_b(x)=y \longleftrightarrow b^y=x
  2. log_b(xy)=log_bx+log_by
  3. log_b\frac{x}{y}=log_bx-log_by


Angle0\degree30 \degree45 \degree60 \degre90 \degree
TanA0\frac{1}{\sqrt{3}}1\sqrt{3}Not defined
CosecANot defined2\sqrt{2}\frac{2}{\sqrt{3}}1
SecA1\frac{2}{\sqrt{3}}\sqrt{2}2Not defined
CotANot defined\sqrt{3}1\frac{1}{\sqrt{3}}0
Trigonometric ratios asked in CDS examination.
  1. cos^2A +sin^2A=1
  2. 1+tan^1A=sec^2A for 0\degree \leq A \leq 90\degree
  3. cot^2A+1=cosec^2A for 0\degree < A \leq 90\degree
  4. cosecA=\dfrac{1}{sinA}
  5. secA=\dfrac{1}{cosA}
  6. tanA=\dfrac{sinA}{cosA}


  1. (x+y)^2=x^2+2xy+y^2
  2. (x-y)^2=x^2-2xy+y^2
  3. x^2-y^2=(x+y)(x-y)
  4. (x+a)(x+b)=x^2+(a+b)x+ab
  5. (x+y+z)^2=x^2+y^2+z^2+2xy+2yz+2zx
  6. (x+y)^3=x^3+y^3+3xy(x+y)
  7. (x-y)^3=x^3-y^3+3xy(x-y)
  8. x^3+y^3+z^3=(x+y+z)(x^2+y^2+z^2-xy-yz-zx)

Arithmetic Progression[AP]

  1. The general form of an AP is a, a + d, a + 2d, a + 3d, . . . . Where ‘d’ is called the common difference.
  2. If a,b, c are in AP, then b=\dfrac{a+c}{2}.
  3. In an AP with first term ‘a’ and common difference ‘d’, the nth term (or the general term) is given by a_n = a + (n -1) d.
  4. The sum(S) of the first n terms of an AP is given by, S=\dfrac{n}{2}[2a+(n-1)d].
  5. If l is the last term of the finite AP, say the nth term, then the sum of all terms of the AP is given by :S=\dfrac{n}{2}(a+l).

Quadratic equation

  1. A quadratic equation in the variable x is of the form ax^2 + bx + c = 0, where a, b, c are real numbers and a \neq 0.
  2. A real number \alpha is said to be a root of the quadratic equation ax^2 + bx + c = 0, if a \alpha^2 + b\alpha^2 + c = 0.
  3. Quadratic formula: The roots of a quadratic equation ax^2 + bx + c = 0 are given by \dfrac{-b\pm \sqrt{b^2-4ac}}{2a}, provided b^2-4ac\geq0.
  4. A quadratic equation ax^2 + bx + c = 0 has,
    • Two distinct real roots if b^2-4ac > 0.
    • Two equal roots(i.e coincident roots) if b^2-4ac = 0.
    • No real roots if b^2-4ac < 0.

November 2019 current affairs

This current affair is aimed at NDA I 2020, OTA 1 2020 and CDSE 1 2020.

  1. Constitution Day/National Law Day : 26th November: On 26th November 2019, constitution of India adopted. I cam into effect on 26th January 1950. Don’t confuse with republic day which is celebrated in 26th January.
  2. International Film Festival of India: 50th International Film Festival of India was held in Panaji, the capital of Goa which begins on 20th November 2019. The Golden Peacock Award for the Best Film was given to the movie ‘Particles’.Best Director award was give to Lijo Jose Pellissery for the movie ‘Jallikattu’.
  3. 11th BRICS summit: 11th BRICS summit was held in Brazil from 13th to 14th November. Theme for this years summit was “Economic Growth for an Innovative Future.” BRICS is group of countries namely Brazil, Russia, India, China and South Africa.
  4. Dustlik-2019: Dustlik-2019 was a Joint Field Training exercise which began on 4th November between the armies of India and Uzbekistan, this exercise was held in Chirchiq, Uzbekistan. The focus of exercise was warfare and counter terrorism in urban areas.
  5. Athlete of the Year: Eliud Kipchoge, worlds top marathon runner who recently broke 2 hour record and Dalilah Muhammad world 400 meter hurdle champion won World athlete of the year award.
  6. 14th East Asia Summit: 14th East Asia summit was held in Bangkok, Thailand. India is also member of this club.
  7. 13th South Asian games[2019]: 2019 South Asian games are held in Nepal.  Bangladesh, Maldives, Pakistan, Bhutan, Nepal, Sri lanka and India are the South Asian nations taking part in this event.
  8. Regional Comprehensive Economic Partnership (RCEP): RCEP is a agreement free trade agreement of around 10 nations which also includes China. India decided not to join RECP as this would have meant that India had to reduce taxes on import and export, which may have effected not so competitive Indian industries and flooding of Indian market by Chinese and other countries goods.

Please check out the following link https://tejasx.com/exams for complete current affairs from all other months.

How to prepare for NDA I 2020

With 4 months to go for NDA I 2020, it is good time to start preparing for it. 4 months is sufficient amount of time to prepare for NDA exam assuming that you are good with the basics.

In paper two of NDA exams, Physics is the most important part in General knowledge. Around 20 questions are asked in from Physics, questions asked are easy. Physics questions are simple logic or formula based based questions, hardly one or two questions are numerical, where you have to use your pen. So make sure that you know all the basic fundamental and basic formula of physics.

From Biology, history and Chemistry combined 30 questions are asked. To prepare for these it is important that you solve previous year NDA examination question and take a lot of mock exams.

In order to take mock exam of NDA I 2020 use the following link and enroll for online NDA I 2020 examination.


Keep in mind that NDA 1 2020 has negative marking, for each wrong answer there will be 1/3rd negative marking, hence I would advice against too much guess work.

Finally current affair are easy marks. To prepare for current affair read last 7 months of current affairs. Current affair related to sports, awards, military exercises, important dates, economics and governance policies.

When preparing for NDA 1 2020, aim for at least 70 percentage mark to make sure that you absolutely get called for SSB interview. So you have to score good in both Paper-I and Paper-II.

Go through the syllabus of NDA examination, it will give you a better idea as to what the paper will be like.

Each paper is of only two and half hours that is 150 minutes. Which means that you have around one minute to solve each question in NDA I 2020. 150 minutes time is more that enough if you are well prepared. At TejasX, we have designed the questions/quiz according to this pattern only, with time limit and negative marking so that you get real feel of the examination. So make sure that you attempt these mock exams provided by TejasX and test where you stand and what is your speed.

NDA examination gives you a wonderful chance to enter armed forces and live a nice life. So take your preparation seriously and study as much as you can. Don’t take this exam lightly as some might thinking that it is not as tough.