ISRO ISTRAC Syllabus 2026 & Exam Pattern: Post-wise Syllabus, CBT Pattern, Marking Scheme & PDF

ISRO 2026 Technical Assistant Previous Year Question Paper PDF Download

ISRO 2026 Technician-B Previous Year Question Papers PDF Download

ISRO ISTRAC Exam Pattern 2026: Post-Wise Details

The exam pattern for this recruitment cycle follows the same structure ISRO/ISTRAC has consistently used for Technician, Draughtsman, Technical Assistant and Scientific Assistant recruitments in previous cycles. There are two major components: the Written Test/Computer Based Test (CBT) and the Skill Test.

ISRO ISTRAC Exam Pattern 2026 – Technical Assistant, Scientific Assistant and Library Assistant-A

The written test/CBT for these posts consists of 80 multiple choice questions to be completed in 1.5 hours. Each correct answer carries +1 mark, while each wrong answer attracts negative marking of -0.33 marks. The Skill Test that follows is of qualifying nature, conducted for 100 marks.

Pass criteria for the written test: Unreserved candidates need to score 32 out of 80 marks, while reserved category candidates (only where the post is reserved) need to score 24 out of 80 marks.

Pass criteria for the Skill Test: Unreserved candidates must score 50 out of 100 marks, and reserved category candidates must score 40 out of 100 marks.

ISRO ISTRAC Exam Pattern 2026 – Technician-B and Draughtsman-B

These trade-based posts also follow the same 80 MCQs in 1.5 hours pattern with +1 and -0.33 marking. The pass criteria mirror the Technical Assistant pattern: 32/80 for unreserved and 24/80 for reserved candidates in the written test, and 50/100 and 40/100 respectively in the Skill Test.

An important note for Technician-B and Draughtsman-B candidates: in case of a tie in written test scores and academic marks of the notified qualification (NAC/NTC/ITI), candidates possessing a valid NAC (National Apprenticeship Certificate) score will get preference over those without an NAC score.

ISRO ISTRAC Exam Pattern 2026 – Cook-A

The Cook-A written test/CBT is comparatively shorter, with 60 MCQs to be completed in 1.5 hours, using the same +1 and -0.33 marking scheme. The Skill Test for this post is purely qualifying in nature, conducted for 100 marks, and candidates must secure a minimum of 60 marks to qualify. No relaxation in Skill Test marks is applicable for any category for the Cook-A post.

ISRO ISTRAC 2026 – Shortlisting Ratio for Skill Test

Across all posts, candidates who qualify the written test/CBT will be shortlisted for the Skill Test in a 1:5 ratio, subject to a minimum of 10 candidates being called per post/category. Final selection is based purely on marks obtained in the written test/CBT among those who clear the Skill Test on a go/no-go basis.

ISRO ISTRAC Exam 2026 – Tie-Breaker Rule

If two or more candidates score identically in the written test/CBT, the academic marks obtained in the essential qualification notified for the post will act as the tie-breaker.

ISRO ISTRAC 2026 – Medium of Exam

Candidates have the option to attempt the written test/CBT in either Hindi or English medium.

ISRO ISTRAC 2026 Exam Mode & Centres

ISTRAC reserves the right to conduct the written test/CBT online or offline, and it may be held in Bengaluru or other cities across India depending on candidate distribution. The Skill Test, however, will be conducted only in Bengaluru for all shortlisted candidates, regardless of their exam centre for the written test.

ISRO ISTRAC Technician-B Syllabus 2026 (Post Code 001 – ITI Electronics Mechanic)

Candidates applying for the ITI Electronics Mechanic Technician-B post should prepare from the NCVT-prescribed Electronics Mechanic/Technician Power Electronic Systems/Mechanic Consumer Electronic Appliances/Mechanic Industrial Electronics trade syllabus, covering:

• Basic electrical and electronics fundamentals (Ohm’s Law, resistors, capacitors, inductors)
• Semiconductor devices (diodes, transistors, SCR, FET)
• Analog electronics (amplifiers, oscillators, power supplies)
• Digital electronics (logic gates, flip-flops, counters, multiplexers)
• Electronic measuring instruments (multimeter, CRO, function generator)
• Power electronics and consumer electronic appliance repair
• Basic electrical wiring and safety practices
• PCB assembly, soldering techniques, and component identification
• Workshop calculation and science related to the trade
• Engineering drawing basics relevant to electronics trade
• Employability skills (as per NCVT common curriculum: communication skills, ICT literacy, basic workplace safety)

ISRO ISTRAC Technician-B Syllabus 2026 (Post Code 002 – ITI Carpenter)

For the ITI Carpenter trade, preparation should be based on the NCVT Carpenter trade syllabus, covering:

• Wood identification, properties, and seasoning of timber
• Carpentry hand tools and power tools
• Joinery techniques (mortise and tenon, dovetail, lap joints)
• Furniture making and wood finishing techniques
• Reading and interpreting carpentry/civil drawings
• Measurement and marking tools used in carpentry
• Safety practices in carpentry workshops
• Trade-related workshop calculation and science
• Employability skills (common NCVT module)

ISRO ISTRAC Draughtsman-B Syllabus 2026 (Post Code 003 – Draughtsman Civil)

Candidates for the Draughtsman Civil post should prepare from the NCVT Draughtsman Civil trade curriculum, covering:

• Building drawing and construction fundamentals
• Reading and preparing plans, elevations, and sections of buildings
• Surveying basics and site plan preparation
• Building materials (cement, bricks, steel, aggregates)
• Estimation and costing basics
• AutoCAD/computer-aided drafting fundamentals (where applicable)
• Building bye-laws and basic construction codes
• Structural drawing basics (RCC elements, foundations)
• Workshop calculation and science related to civil trade
• Employability skills module

ISRO ISTRAC Draughtsman-B Syllabus 2026 (Post Code 004 – Draughtsman Mechanical)

For Draughtsman Mechanical, focus areas from the NCVT curriculum include:

• Machine drawing fundamentals (orthographic projection, sectional views)
• Limits, fits, and tolerances
• Reading and preparing mechanical component drawings
• Assembly and detail drawings of machine parts
• Sheet metal drawing basics
• Fasteners, welding symbols, and their representation in drawings
• AutoCAD/computer-aided drafting fundamentals (where applicable)
• Workshop calculation and science related to mechanical trade
• Employability skills module

ISRO ISTRAC Technical Assistant Syllabus 2026 (Post Code 005 – Electronics)

The Technical Assistant (Electronics) post requires a First Class Diploma in Electronics, so preparation should cover diploma-level core subjects, including:

• Basic electrical engineering (circuit laws, AC/DC fundamentals)
• Analog electronics (amplifiers, oscillators, feedback circuits)
• Digital electronics (combinational and sequential circuits, microprocessors basics)
• Communication engineering fundamentals (modulation techniques, antennas, basic satellite/radar communication concepts, relevant given ISTRAC’s TTC and ground station operations)
• Electronic devices and circuits (diodes, transistors, op-amps)
• Control systems basics
• Electronic instrumentation and measurement
• Microcontrollers and embedded systems fundamentals
• Power electronics basics
• General engineering mathematics and applied physics relevant to the diploma curriculum

ISRO ISTRAC Technical Assistant Syllabus 2026 (Post Code 006 – Mechanical)

For Technical Assistant (Mechanical), preparation should be based on diploma-level Mechanical Engineering subjects, including:

• Engineering mechanics and strength of materials
• Thermodynamics and heat transfer fundamentals
• Fluid mechanics and hydraulic machines
• Machine design basics
• Manufacturing processes (casting, welding, machining)
• Production and industrial engineering fundamentals
• Theory of machines and machine elements
• Material science fundamentals
• Engineering drawing and CAD basics
• Applied mathematics relevant to mechanical diploma curriculum

ISRO ISTRAC Scientific Assistant Syllabus 2026 (Post Code 007 – Computer Science)

The Scientific Assistant (Computer Science) post requires a First Class B.Sc. with Computer Science as the main subject, so the syllabus should cover core computer science degree topics, including:

• Programming fundamentals (C, C++, Python basics)
• Data structures and algorithms
• Database management systems (DBMS/SQL basics)
• Operating systems fundamentals
• Computer networks basics
• Object-oriented programming concepts
• Software engineering fundamentals
• Computer organization and architecture basics
• Web technologies fundamentals (HTML, basic scripting)
• General computer awareness and IT fundamentals relevant to B.Sc. Computer Science curriculum

ISRO ISTRAC Scientific Assistant Syllabus 2026 (Post Code 008 – Mathematics)

For the Scientific Assistant (Mathematics) post requiring a First Class B.Sc. with Mathematics as the main subject, preparation should focus on core mathematics degree topics, including:

• Algebra (group theory, matrices, determinants)
• Calculus (differential and integral calculus, multivariable calculus)
• Differential equations (ordinary and partial)
• Real analysis and complex analysis fundamentals
• Probability and statistics
• Numerical methods
• Vector calculus and linear algebra
• Discrete mathematics basics (useful given computational aspects of ISTRAC’s work)

ISRO ISTRAC Library Assistant-A Syllabus 2026 (Post Code 009)

The Library Assistant-A post requires a Graduate degree plus a First Class Master’s in Library Science/Library and Information Science, so the syllabus should cover:

• Library classification systems (Dewey Decimal Classification, Colon Classification)
• Cataloguing rules and practices (AACR2, RDA basics)
• Library management and administration
• Information sources and reference services
• Library automation and integrated library management systems (ILMS)
• Digital libraries and institutional repositories
• Information retrieval systems
• Computer applications in libraries (since the Skill Test for this post specifically tests computer literacy)
• Basic library legislation and copyright awareness

ISRO ISTRAC Cook-A Syllabus 2026 (Post Code 010)

Since Cook-A requires SSLC/SSC pass plus 5 years of practical experience as a cook in a well-established hotel/canteen, the written test/CBT (60 MCQs) is likely to cover practical and applied knowledge such as:

• Basic food preparation techniques and cooking methods
• Food hygiene and safety practices (FSSAI-related basic awareness)
• Kitchen equipment handling and maintenance
• Menu planning and portion control basics
• Nutrition fundamentals
• Storage and preservation of food items
• Institutional/canteen catering practices
• General awareness related to catering operations

ISRO ISTRAC 2026 Preparation Tips for All Posts

• Prioritize accuracy over guesswork since the Written Test/CBT carries 0.33 negative marks for every incorrect answer.
• Revise your core syllabus thoroughly using ITI, Diploma, or Degree textbooks relevant to your post.
• Practice previous ISRO question papers for Technician-B, Draughtsman-B, Technical Assistant, and Scientific Assistant posts whenever available.
• Take regular mock tests to improve speed, accuracy, and time management.
• Practice solving 80 MCQs within 1.5 hours to get comfortable with the actual exam duration.
• Focus on curriculum-based questions, as the written examination is based on the prescribed educational qualification syllabus.
• Strengthen weak topics by analyzing mistakes made during mock tests and previous papers.
• Prepare for the Skill Test alongside the CBT, as only candidates who qualify the written test are shortlisted for the next stage.
• Avoid random guessing and attempt only those questions where you are reasonably confident to maximize your final score.
• Follow a consistent revision schedule in the final weeks before the exam to retain important concepts and improve confidence.