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The correct choice is (b) False

Best explanation: FHSS stands for frequency hopping spread spectrum and DSSS for DIRECT sequence spread spectrum. DSSS TECHNOLOGY is more advantageous as it is LESS susceptible to NOISE and can not be easily jammed or HIJACKED.

Correct answer is (a) Satellite

Best explanation: Since the MQ-9 has an endurance of 28HRS and range of 3,200nm it needs a communication system that is not affected by the curvature of the Earth. Satellite communication system is best suited for this as a MINIMUM of 3 SATELLITES is ENOUGH to have communication around the world using the technique of TRIANGULATION.

Correct choice is (d) 50,000ft

The best explanation: HALE CORRESPONDS to High ALTITUDE and Long Endurance AIRCRAFT. It has a service ceiling of 50,000ft and an endurance greater than 20HRS.

Right answer is (a) True

Easy explanation: ALTHOUGH an FMS is NEEDED for UAVS, for simple UAVs such as radio controlled models does not require FMS. The FMS functions of many smaller UAVs are CARRIED in the ground station.

The CORRECT option is (c) Low ACCURACY

The explanation is: Terrain reference navigation, TRN, SYSTEMS are used in cruise missiles and aircraft. One of the major advantage in UAV/UCAV applications is that they are COMPLETELY self-contained and unjammable as well as of high accuracy. They are completely independent of any external systems such as satellites or ground STATIONS.

The correct choice is (d) 10^-5/hour

Explanation: SINCE the UAV is unmanned its failure would not be fatal, the failure probability for a UAV is less than that of a normal aircraft with a figure of 10^-5/hour. ALTHOUGH, a failure might cause damage to the UAV and where it falls. The failure probability DIFFERS from MISSION to mission.

Correct option is (b) Advanced integrated avionic architecture

The best I can explain: The JOINT Strike Fighter’s SENSORS, communications, and flight-control systems will blend TOGETHER more tightly than any other combat aircraft in HISTORY, and will revolve around high-speed fiber-optic data buses and powerful commercial off-the-shelf microprocessors using advanced integrated avionic architecture.

Correct answer is (a) HMDs

To elaborate: Since the UAV is unmanned it does not require HDD or HUD but since the pilot is going to be on the ground CONTROLLING the UAV, HMDs are considered to be cost-effective and also show good performance and SITUATIONAL AWARENESS.

Correct choice is (b) Pave PILLAR architecture

Easy explanation: In a TYPICAL single seat fighter aircraft the pilot has to play the role of both controlling the aircraft and weapons management as OPPOSED to a TWIN seat aircraft where the pilot flies the plane and the RIO or Radar Intercept Officer manages the weapons. Pave pillar architecture allows the pilot to be the weapons system manager WITHOUT which single seat fighter aircraft like F-22 and the F-35 would not have been possible.

The correct answer is (a) True

Easy EXPLANATION: The REASON why time division multiplexing is possible is that the DATA transfer form the component to the COMPUTER is DIGITAL. This reduces a huge amount of wiring as the data transfer is serial and also the error is not propagated.

The correct answer is (a) COMPLEX DESIGN

Explanation: The centralized architecture is ONE where all the components are linked to a single main frame computer for processing. The design is simple and software preparation and UPDATE is easy as the computer is easily accessible but requires long data BUSES running from the component to the computer which increases weight.

The correct option is (C) Federated architecture

Easiest EXPLANATION: Federated avionic architecture is a type of SECOND generation architecture in which the data from each avionic component was converted into digital INFORMATION and sent to the MAIN frame computer. This technology was called the DIAS or Digital Avionics Information System.

The correct option is (d) Increased life CYCLE

Easy explanation: An INTEGRATED modular avionics architecture system reduces weight as the processors are centralized and relatively fewer components are required. It is also easy for maintenance as each component is a separate block which can be repaired or replaced easily. Modular avionics architecture ensures that the SOFTWARE used is hardware INDEPENDENT and can be updated in the future. However they do not ensure increased life cycle of the components, the life cycle of a component is same if the architecture is modular or any other type.

Correct option is (c) Disjoint or independent architecture

The BEST explanation: Disjoint architecture is a First GENERATION architecture where the avionics systems were stand alone black boxes which had separate sensors, PROCESSORS and displays and were linked TOGETHER by point to point wiring.

Correct answer is (a) True

Explanation: The NETWORK PROVIDES 100 Mbits/s full duplex (two way) communication and provides FLEXIBILITY to manage any change in the data communication between the connected systems without WIRING modifications.

Correct answer is (C) Core DIAMETER

To explain: The MAJOR difference between SINGLE mode fibre and multi-mode fibre is that the core diameter of single mode fibre is of the same order of MAGNITUDE as the wavelength of the light source (laser diode). Pulse dispersion is reduced in single mode fiber.

Correct answer is (B) Total internal reflection

To ELABORATE: The transmission of light signals ALONG any optical fibre depends on the optical property of total internal reflection. The transmitted light pulses get reflected by the cladding in the fiber cable at the same TIME MOVE in the forward direction. One main disadvantage of fiber optic cable is that it cannot be easily bent.

Right option is (b) Single twisted pair cable with shielding

Easiest explanation: The MIL STD 1533 bus is formed as a single twisted cable pair with one layer of shielding and jacketing and with a MAXIMUM length of 100 m (328 ft). Although direct COUPLING to the bus is allowed, this is generally not used in order to avoid the risk of one TERMINAL shorting out the bus. The bus connection is typically via a transformer coupled stub so that shorting of the stub is ISOLATED from the bus.

Correct ANSWER is (d) Avionics FULL DUPLEX Switched ETHERNET

For explanation: The version which has been adapted for airborne applications is known as the ‘Avionics Full Duplex Switched Ethernet’, which has been shortened to ‘AFDX Ethernet’ network. It meets the civil aircraft avionic system requirements in all aspects and its commercially sourced components make it a very competitive system.

Correct option is (a) TIME DIVISION Multiplexing

Easy explanation: The individual avionic sub-systems are INTERCONNECTED by means of a digital DATA bus SYSTEM. This enables the system to communicate with each other and transfer serial data information using time division multiplexing.

Correct option is (c) Electrical and Optical DATA bus

To explain I would say: Data bus systems are the ESSENTIAL enabling technologies of avionic systems integration in both federated and integrated modular avionics architectures. They can be broadly divided into electrical data bus systems where the data are transmitted as electrical PULSES by WIRES, and optical data bus systems where the data are transmitted as LIGHT pulses by optical fibres.

The CORRECT option is (B) Federated architecture

The explanation: Federated architectures ESSENTIALLY consist of a number of interconnected but functionally INDEPENDENT sub-systems with some degree of central computer control of overall operating modes. System is loosely coupled and are connected via a time shared multiplex HIGHWAY.

Right answer is (c) Fiber optic cable

Easy explanation: A single SCREENED twisted pair of wires only is required with such an encoding system to transmit information data RATES of up to 1 to 2 Mbits/s. Higher data rates of up to 100 Mbits/s can be transmitted using a SUITABLY screened coaxial electrical cable and information at EVEN higher data rates can be transmitted as coded light pulses using a fibre optic cable. Radio COMMUNICATION is not for data transfer between aircraft components.

Right answer is (d) Used only in America

Easiest EXPLANATION: ARINC is a non-profit-making organization in the USA which is run by the civil airlines with industry and establishment representation, which defines systems and equipment specifications in terms of functional requirements, PERFORMANCE and accuracy, input and output interfaces, environmental requirements and PHYSICAL dimensions and electrical interfaces. For example, air data computers, attitude heading reference systems, INS, communication radio equipment, data BUS systems, etc. Although it is a US BASED company the system standard is worldwide.