The SSLV's Payload Fairing (Heat Shield) has a diameter of:
- 3.2 meters
- 1.5 meters
- 2.1 meters
- 2.8 meters
Explanation: The SSLV uses a 2.1-meter diameter ogive-shaped payload fairing, slightly wider than the 2.0-meter rocket body to accommodate larger payloads.
The SS2 stage (second stage) of the SSLV carries approximately how many tonnes of solid propellant?
- 15 tonnes
- 25 tonnes
- 4 tonnes
- 7.7 tonnes
Explanation: The second stage, SS2, is significantly smaller than the first, carrying about 7.7 tonnes of HTPB propellant.
The successful induction of SSLV into ISRO's fleet primarily helps free up which other vehicle for heavier, complex missions?
- RH-200
- PSLV
- GSLV Mk II
- LVM3
Explanation: Historically, the PSLV was used even for small satellites. SSLV now handles the 500 kg segment, allowing PSLV to focus on 1500 kg+ missions and complex multi-orbit tasks.
Which of the following is a primary cost-saving feature of the SSLV?
- Launching from a floating platform
- Using kerosene as a primary fuel
- Use of used components from old PSLV flights
- Simplified avionics and minimal manual intervention
Explanation: The SSLV features integrated avionics, high modularity, and a design that requires only about 6 people for launch operations, drastically reducing costs.
The 'AzaadiSAT' payloads launched on SSLV-D1 and D2 were developed primarily by:
- ISRO senior scientists
- School students across India
- Defense Research and Development Organization
- Private start-ups from Bangalore
Explanation: AzaadiSAT was a collaborative mission involving 750 girl students from 75 rural schools across India, coordinated by 'Space Kidz India'.
What is the specific impulse (Isp) of the solid stages in the SSLV (vacuum)?
- 310 seconds
- 450 seconds
- 285 seconds
- 220 seconds
Explanation: Modern HTPB-based solid motors in the SSLV provide a vacuum specific impulse of approximately 285 to 290 seconds.
The SS2 and SS3 stages of the SSLV are controlled during flight primarily through:
- Jet Vanes
- Secondary Injection
- Flex Nozzle Actuators
- Aerodynamic Fins
Explanation: Unlike the PSLV's SITVC, the SSLV uses high-precision Electromechanical Flex Nozzle Actuators for thrust vector control in its upper solid stages.
Which material is used for the Inter-stage structures (ISA) of the SSLV to reduce weight?
- Copper-Beryllium
- Carbon-Fiber Reinforced Plastic
- Maraging Steel
- Mild Steel
Explanation: SSLV utilizes Carbon-Fiber Reinforced Plastic (CFRP) for its inter-stage and payload fairing structures to maximize the payload-to-weight ratio.
The SSLV-D3 satellite, EOS-08, utilized a 'Bus' platform named:
- I-1K
- Micro-SAT
- Small Satellite Bus
- IMS-1
Explanation: EOS-08 was built upon the heritage of the IMS-1 (Indian Mini Satellite-1) bus architecture.
The 'Velocity Trimming Module' (VTM) is integrated into which section of the vehicle?
- Inside the heat shield
- Between SS1 and SS2
- Inside the SS1
- Above the SS3
Explanation: The VTM sits on top of the third solid stage (SS3) and carries the payload adapter on its upper deck.
Which specific separation mechanism is used to jettison the SSLV's payload fairing?
- Pneumatic pushers
- Zip-cord pyrotechnics
- Hydraulic pistons
- Linear bellows system
Explanation: SSLV utilizes a contamination-free 'Zip-cord' (linear explosive) based separation system to split and jettison the two halves of the heat shield.
How many satellites can the SSLV typically deploy in a single 'rideshare' mission?
- Only one
- Exactly 75
- Up to 8â10
- More than 500
Explanation: While it depends on the size and mass, the SSLV is designed to efficiently carry a cluster of 8 to 10 small satellites as part of its rideshare capability.
Which of the following describes the 'Intelligent Control' feature implemented in the SSLV avionics?
- AI-based weather prediction
- Remote refueling capability
- Fault-tolerant 'Salvage' logic
- Manual override capability
Explanation: SSLV features an 'on-the-fly' navigation and guidance system that can independently decide the best orbital injection strategy if anomalies are detected during ascent.
Which organization manages the 'AzaadiSAT' series of payloads carried by the SSLV?
- Skyroot Aerospace
- Agnikul Cosmos
- Space Kidz India
- Bellatrix Aerospace
Explanation: Space Kidz India is the Chennai-based startup that coordinated the development of AzaadiSAT by school students.
The SSLV-D1 mission carried which primary Earth Observation Satellite?
- EOS-03
- EOS-02
- EOS-01
- EOS-05
Explanation: EOS-02 was an experimental optical imaging satellite with high spatial resolution designed specifically for the maiden flight of the SSLV.
The SSLV-D3 mission EOS-08 satellite carried a payload called 'Sichy'. What was its function?
- Navigation signal study
- Gamma-ray monitoring
- Soil moisture analysis
- Cloud cover imaging
Explanation: The SiC-based Gamma Ray Spectrometer (Sichy) was designed to monitor high-energy radiation environment and detect Gamma-Ray Bursts (GRBs).
The SSLV-D3/EOS-08 mission successfully demonstrated a new technology for 'thermal management' using:
- Deployable radiators
- Integrated Heat Pipes
- Carbon-nanotube paint
- Liquid nitrogen cooling
Explanation: The EOS-08 satellite carried on SSLV-D3 featured advanced technology demonstrations, including integrated structural-thermal management using heat pipes.
What was the orbit inclination achieved during the successful SSLV-D2 mission?
- 0 degrees
- 45 degrees
- 37 degrees
- 98 degrees
Explanation: SSLV-D2 was launched into a 450 km circular orbit with an inclination of approximately 37.2 degrees.
Which subsidiary of ISRO is primarily responsible for the commercialization of the SSLV through private industry partnerships?
- Physical Research Laboratory
- IN-SPACe
- NewSpace India Limited
- Antrix Corporation
Explanation: NewSpace India Limited (NSIL) is the commercial arm of ISRO tasked with transferring SSLV technology to the private sector and managing commercial launch services.
Compared to the PSLV, which takes several weeks to integrate, the SSLV is designed to be integrated and ready for launch within:
- 72 hours
- 10 days
- 24 hours
- 15 days
Explanation: One of the key advantages of SSLV is its 'launch-on-demand' capability, with a turnaround time of just 72 hours (3 days) using a very small team.
The Velocity Trimming Module (VTM) of the SSLV is equipped with how many 50N thrusters for reaction control?
- Sixteen
- Four
- Eight
- Twelve
Explanation: The VTM carries sixteen 50N thrusters in total; eight are for velocity increments (axial) and eight are for reaction control (RCS) to manage orientation.
The SSLV is specifically optimized for which emerging segment of the global space market?
- Small satellite constellations
- Heavy communication satellites
- Manned spaceflight
- Interplanetary probes
Explanation: SSLV targets the rapidly growing market for small satellites (Smallsats) and CubeSats, offering a low-cost, quick-turnaround alternative to larger rockets.
The SSLV-D2 mission carried 'Janus-1', which was the world's first satellite to be:
- Entirely 3D printed
- Launched without a protective fairing
- Powered by nuclear energy
- Fully software-defined and cloud-connected
Explanation: Janus-1, developed by Antaris, was a technology demonstrator for a smart, software-defined satellite platform.
What is the maximum payload capacity of the SSLV for a 500 km Low Earth Orbit (LEO)?
- 300 kg
- 750 kg
- 500 kg
- 1000 kg
Explanation: The SSLV is designed to carry a 500 kg payload to Low Earth Orbit (LEO) and roughly 300 kg to Sun-Synchronous Orbit (SSO).
Which specific sensor anomaly led to the 'Salvage Mode' execution during the SSLV-D1 mission?
- Pressure Transducer
- Sun Sensor
- Star Tracker
- MEMS Accelerometer
Explanation: A transient vibration during the second stage separation saturated the MEMS-based accelerometers, causing the software to misinterpret the data and trigger an emergency salvage logic.
What is the typical diameter of the SSLV rocket body?
- 2.8 meters
- 3.2 meters
- 2.0 meters
- 1.0 meters
Explanation: The SSLV has a uniform diameter of 2.0 meters across its three main stages.
The successful SSLV-D2 mission in February 2023 carried which primary ISRO satellite?
- EOS-08
- EOS-04
- EOS-06
- EOS-07
Explanation: SSLV-D2 successfully placed EOS-07, along with Janus-1 and AzaadiSAT-2, into their intended 450 km circular orbits.
How much thrust is generated by each axial thruster of the VTM module?
Explanation: The VTM is powered by sixteen 50N thrusters (eight for axial thrust and eight for RCS).
The SSLV configuration consists of how many solid propulsion stages?
Explanation: SSLV utilizes three solid propulsion stages (SS1, SS2, and SS3) followed by a liquid-based Velocity Trimming Module (VTM) for precise orbital insertion.
What is the expansion ratio of the SS1 stage nozzle in the SSLV?
Explanation: The first stage (SS1) nozzle is optimized for sea-level to mid-altitude performance with a relatively low expansion ratio of approximately 14.
What type of propellant is used in the three main stages of the SSLV?
- Liquid Oxygen and Kerosene
- UDMH and Nitrogen Tetroxide
- Liquid Hydrogen and Liquid Oxygen
- HTPB based solid propellant
Explanation: All three primary stages of the SSLV use Hydroxyl-terminated polybutadiene (HTPB) based solid propellants, similar to other ISRO solid boosters.
What is the peak vacuum thrust generated by the SS1 motor of the SSLV?
- 1200 kN
- 2500 kN
- 3850 kN
- 4100 kN
Explanation: The SS1 motor is one of the most powerful solid motors in its class, producing a peak vacuum thrust of approximately 3850 kN.
The successfully operationalized SSLV costs approximately how much per launch (estimated)?
- Rs 150 crore
- Rs 30 crore
- Rs 10 crore
- Rs 80 crore
Explanation: One of the major highlights of the SSLV is its low cost, estimated to be around Rs 30-35 crore ($4-5 million) per launch, making it highly competitive globally.
The 'VTM' uses MON-3 as the oxidizer. What does MON stand for?
- Mixed Oxides of Nitrogen
- Molecular Organic Nitrate
- Metallic Oxide Network
- Monatomic Oxygen Nitride
Explanation: MON-3 is 'Mixed Oxides of Nitrogen,' specifically a solution of Nitric Oxide in Nitrogen Tetroxide, commonly used in storable liquid engines.
Which of the following describes the 'Multi-satellite adapter' feature of the SSLV?
- It allows the rocket to dock with the ISS
- It enables the launch of multiple satellites in a single mission
- It acts as a secondary fuel tank for the VTM
- It is a heat shield for atmospheric re-entry
Explanation: The SSLV features a modular multi-satellite adapter that allows it to carry and deploy multiple small satellites into different or similar orbits in one go.
SSLV-D2 mission carried AzaadiSAT-2. How many 'Space-STEM' payloads were integrated into this 8U CubeSat?
Explanation: AzaadiSAT-2 contained 75 individual experimental payloads, representing 75 years of Indian independence, built by girl students.
The VTM module of the SSLV has a total propellant capacity of approximately:
- 50 kg
- 300 kg
- 500 kg
- 100 kg
Explanation: The Velocity Trimming Module carries about 100 kg of liquid propellant to handle the final orbit correction maneuvers.
The SSLV's third stage (SS3) uses which material for its nozzle for high-temperature resistance?
- Stainless steel
- Graphite-epoxy
- Carbon-Carbon composite
- Tungsten
Explanation: ISRO uses advanced Carbon-Carbon (C-C) composites for the nozzles of its solid motors to withstand extreme thermal stresses during the final boost phase.
The term 'Launch on Demand' specifically refers to SSLV's ability to:
- Return to the launch site for reuse
- Launch even in heavy rain
- Change its orbit after launch
- Launch within a few days of a customer request
Explanation: 'Launch on Demand' highlights the quick turnaround and integration time, allowing satellites to be put into space with very short notice compared to traditional months-long schedules.
The SSLV-D2 mission successfully deployed Janus-1, a satellite developed by which entity?
- Dhruva Space
- Skyroot
- Pixxel
- Antaris
Explanation: Janus-1 was a 6U CubeSat from Antaris (USA), designed as a technology demonstrator for their cloud-based satellite design platform.
Which organization provided the GNSS receiver for the SSLV's navigation system?
Explanation: The ISRO Inertial Systems Unit (IISU) developed the integrated inertial navigation system, which includes the GNSS-based position update system.
The SSLV-D3 mission demonstrated the 'SR-0' mission profile. What does this signify?
- Shortest Range
- Zero Residual Velocity
- Standard Reference Orbit
- Sub-orbital recovery
Explanation: The D3 flight aimed for a 'Standard Reference Orbit,' proving the vehicle's repeatability and readiness for commercial induction.
The VTM (Velocity Trimming Module) of the SSLV utilizes which type of propellant system?
- Solid fuel
- Hypergolic liquid fuel
- Cold gas thrusters
- Cryogenic fuel
Explanation: The VTM uses a hypergolic liquid propellant system (MMH and MON3) which allows for multiple restarts and precise thrust control.
What is the primary advantage of the new launch site at Kulasekarapattinam over Sriharikota for SSLV missions?
- It is located in a seismically stable zone
- It is closer to the equator
- No 'dog-leg' maneuver is required for polar launches
- It has better weather year-round
Explanation: From Sriharikota, rockets must fly east and then turn south to avoid flying over Sri Lanka (a 'dog-leg' maneuver). Kulasekarapattinam allows a straight southward flight, saving significant fuel.
The first developmental flight, SSLV-D1, placed satellites into an unstable elliptical orbit instead of a circular one due to:
- Stage separation failure
- Sensor anomaly and software logic
- Engine thrust failure
- Propellant leakage
Explanation: An accelerometer failure during the flight caused the onboard software to trigger a 'salvage mode,' which successfully injected the satellites but into an incorrect, short-lived elliptical orbit.
The SS1 stage of the SSLV is notable for being the first ISRO stage to use which technology for its casing?
- Composite motor case
- Titanium alloy
- Maraging steel
- Aluminum-lithium alloy
Explanation: Unlike the older S139 boosters that use steel, the SSLV stages utilize high-strength, lightweight carbon-epoxy composite motor cases to improve the mass fraction.
Where is the dedicated SSLV Launch Complex (SLC) being developed to handle high-frequency small satellite launches?
- Thumba
- Kulasekarapattinam
- Sriharikota
- Chandipur
Explanation: While initial flights use Sriharikota, a new dedicated launch site is being built at Kulasekarapattinam in Tamil Nadu to allow for direct southward launches into polar orbits.
The 'Velocity Trimming Module' uses a liquid propulsion system known as:
- Pump-fed system
- Pressure-fed system
- Gas-generator cycle
- Staged combustion
Explanation: To keep the vehicle simple and cost-effective, the VTM utilizes a simple pressure-fed system using regulated Helium gas to drive propellants into the thrusters.
In the SSLV-D1 mission, the 'VTM' could not perform its burn because:
- The fuel had frozen
- The stage failed to separate
- The mission was aborted by software
- The ignition system failed
Explanation: Due to the accelerometer anomaly, the software jumped to a 'recovery' logic that bypassed the VTM burn and separated the satellites immediately to prevent a crash, albeit in an incorrect orbit.
SSLV missions are launched from which specific launch pad at the Satish Dhawan Space Centre (SDSC)?
- Second Launch Pad
- First Launch Pad
- A Sounding Rocket Pad
- Third Launch Pad
Explanation: The developmental flights of SSLV (D1, D2, and D3) were conducted from the First Launch Pad (FLP) at Sriharikota.
The velocity required for a satellite to stay in a circular LEO at 500 km altitude is roughly:
- 28.0 km/s
- 3.5 km/s
- 7.6 km/s
- 11.2 km/s
Explanation: To maintain a circular orbit in LEO, the SSLV must accelerate its payload to approximately 7.6 km/s (roughly 27,000 km/h).
The total propellant mass loaded in the SS1 (first stage) of the SSLV is approximately:
- 45 tonnes
- 110 tonnes
- 15 tonnes
- 87 tonnes
Explanation: The first stage, SS1, is the largest and carries approximately 87 tonnes of solid HTPB propellant to provide the initial massive lift-off thrust.
What is the approximate height of the SSLV vehicle?
- 20 meters
- 44 meters
- 52 meters
- 34 meters
Explanation: The SSLV is much smaller than the PSLV (44m) or GSLV (51m), standing at approximately 34 meters tall.
The SS3 stage (third stage) of the SSLV has a burn time of approximately:
- 160 seconds
- 105 seconds
- 240 seconds
- 60 seconds
Explanation: The third stage solid motor, SS3, burns for approximately 105 seconds to provide the final major velocity increment.
Which onboard computer architecture is utilized by the SSLV for its Integrated Main Computer?
- LEON-3 based processor
- ARM Cortex-M0
- Intel i9 Mobile
- SCL-1802
Explanation: SSLV uses high-performance, radiation-hardened LEON-3 series processors (like the Vikram processor) for its miniaturized avionics package.
The SSLV-D2 mission included a payload called 'Janus-1'. How many days did it take to build this satellite using their cloud platform?
- 300 days
- 10 months
- 10 months
- Less than 1 year
Explanation: Janus-1 was notable for its rapid development, taking only 10 months from concept to launch-ready status.
Which control system is used for the SS1 stage of the SSLV during its ascent?
- SITVC system
- Reaction Control System
- Fins and rudders
- Flex nozzle control
Explanation: The SSLV uses a modern Flex Nozzle Control (FNC) system for its solid stages to provide pitch and yaw control during flight.
The total lift-off mass of the SSLV is approximately:
- 640 tonnes
- 80 tonnes
- 320 tonnes
- 120 tonnes
Explanation: The SSLV has a lift-off mass of approximately 120 tonnes, significantly lighter than the PSLV's ~320 tonnes.
Which specific module in the SSLV is responsible for terminal velocity corrections and precise satellite separation?
- Solid Booster Module
- Apogee Kick Motor
- Cryogenic Upper Stage
- Velocity Trimming Module
Explanation: The Velocity Trimming Module (VTM) is a liquid-propellant stage that performs final adjustments to ensure the satellites are placed in their precise intended orbits.
What was the primary payload of the SSLV-D3 mission, which marked the completion of the SSLV development phase in August 2024?
- EOS-07
- EOS-08
- Cartosat-3
- Oceansat-3
Explanation: The SSLV-D3/EOS-08 mission was the final developmental flight of the SSLV, making the vehicle operational for future commercial and national missions.