Flame spread over liquids is of high importance because of its relation to fire hazards in liquid fuel spillages. Aviation fuels mixed with nanoparticles are rising as promising higher performance fuels for high-end applications. Fire safety characterization of aviation fuels mixed with nanoparticles is paramount to the successful implementation of these new fuels in the aerospace/aviation industry. In this paper, measurements of the flame spread rate on top of a fuel pool of Jet A mixed with carbon nanoparticles are reported. Multi-Walled Carbon Nanotubes (MWCNT) with a nominal diameter of 30-50 nm were added in concentrations varied between 2 g/L and 6 g/L. Jet A temperature was varied between 30oC to 100oC, and a Nd:YAG laser was used to ignite the fuelair mixture established over the liquid fuel pool. Flame spread rate was observed to decrease with increased nanoparticle concentration for all temperatures. Reductions in the flame spread rate up to 50% were observed which are relevant for fire safety of liquids fuels.

Undesirable hot surface ignition of flammable liquids is one of the hazards in ground and air transportation vehicles, which primarily occurs in the engine compartment. In order to evaluate the safety and sustainability of candidate replacement fuels with respect to hot surface ignition, a baseline low lead fuel (Avgas 100 LL) and four experimental unleaded aviation fuels recommended for reciprocating aviation engines were considered. In addition, hot surface ignition properties of the gas turbine fuels Jet-A, JP-8, and JP-5 were measured. A test apparatus capable of providing reproducible data was designed and fabricated to experimentally investigate the hot surface ignition characteristics. A uniform surface temperature stainless steel plate simulating the wall of a typical exhaust manifold of an aircraft engine was used as the hot surface. Temperature uniformity of ±5°C was achieved on the stainless steel plate by virtue of its being bolted to a copper plate in which five automatically controlled 1000 W electrical cartridge heaters were inserted. A programmable syringe pump was used to dispense ~25 μL fuel drops onto the hot surface. Testing was performed in a quiescent environment with the exception of a mild upward flow created by an exhaust fan aiding the buoyant plume created by the hot plate. Ignition and flame propagation events were recorded using visible and midinfrared still and video imaging. The ignition and flame propagation events are transient and occur at randomly distributed locations on the hot surface. To characterize the ignition event statistically, the surface temperature leading to at least one ignition out of the number of drops and the surface temperature resulting in the ignition of all of the drops were recorded. The results of the experiment confirmed that the experimental variations in the drop size, drop velocity, plume characteristics, surface properties including temperature changes, and the nonlinear dependence of temperature of the chemical reaction rate lead to the probabilistic nature of the ignition event. The results of the experiment are of practical value in designing vehicular ignition and safety systems.

With the increase in energy consumption, charging of aircraft batteries with external electrical source has become ever demanding need. The concept of harvesting electrical energy onboard has aroused a renewed interest in humans. In this context, a piezoelectric generator is proposed that harvests mechanical vibrational energy available in huge amount from aircraft engine's vibrations. Embarked piezoelectric transducer, which is an electromechanical converter, when sandwiched between engine cowl, undergoes mechanical vibrations and thereby produce electricity. A static converter transforms the electrical energy in a suitable battery recharging voltage. Values of generated electrical power are discussed further in the paper.

In this paper the authors present the use of electromagnetic forces to make vertical landing possible for higher payloads. The proposed theoretical model uses the concept of generation of alternating electromagnetic fields by AC current which could safely land the payloads. This application brings out potential use of linear synchronous motors (LSM) in field of aerospace. The setup used for this purpose is an integration of numerous LSMs placed systematically in a cylindrical manner. The potential advantages of this system are increased ability to land heavier payloads by vertical landing and controlled touch-down in final stages. A highly controlled re-entry angle and trajectory are mandatory requirements for successful implementation of this system. This system provides a wide range of shapes of the vehicles that can sustain re-entry conditions.

The underlying paper deals with mode of operation of axial flow air compressors. Unlike the conventional axial compressors design that are driven by a motor or a turbine (in case of heavy machinery), the proposed model of the compressor uses synchronous motor arrangement for rotation and initial start-up. Blades will be made of magnetic materials or would be given magnetic coatings so that, blades can react to the induced magnetic field. This new model is expected to perform better and would have better speed control as that of conventional ones. The paper does not deal with any new design or configuration of the blades or blade profile. Magnetic materials and coatings would be discussed in later sections and also better ones based on various properties such as magnetic field strength, tensile strength etc. have been discovered as the fields of further research and development.

The paper deals with the reusability of command modules used during Apollo space missions. During Apollo missions in 1960-70’s the module surface becomes charred up to some extent, hence decreasing the strength and scope of further reusability of the module. A new design has been proposed and simulation results have revealed the possibility to reuse the module again for another mission. The new design has incorporated an in-built mechanism that will extend some part of the module surface outwards near to the periphery of the base of the module. The design, mechanism, material and other details are discussed in succeeding sections. New ablative material has been introduced for more getting more promising

The underlying paper presents the use of lasers in aircraft engines for combustion. The proposed theoretical model of an aircraft engine uses laser as a source to ignite fuel and thereby imparting propulsive power to the aircraft. Lasers being a promising source of energy provide an option of complete and uniform heating of the air-fuel mixture which ensure complete and clean combustion of fuel. Main emphasis for conceptualization of this paper is to make aircraft industry greener. Therefore, laser guns as an ignition source also demonstrate a unique property of sterilizing the air that passes through its path. So, the air available for combustion is free from organic substances and exhaust formed will be less polluting as compared to conventional engine exhausts. Some of the research works that have been completed do exhibit very promising results, which will be discussed in upcoming sections. Keywords: Aircraft propulsion technique, laser technology, aircraft fuel

The evolution in aircraft industry has brought to us many new aircraft designs. Each and every new design is a step toward a greener tomorrow. Design plays a vital role in deciding the flight characteristics and determining its efficiency. The proposed design has been designed keeping 100,000 lbs as the payload. Raked wingtips, canards, and elliptical shaped fuselage are the highlighting features of the proposed design. Reduction of drag will also be observed due to delay in separation point. Expected outcome of proposed design is less amount of fuel burn because of reduction in drag.