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Abstract

As the rotor configuration has the most impact on helicopter properties, the process of determination the assumptions for rotor design is a very important factor in the early stage of rotorcraft development. The following paper presents a mechanical analysis process used at the Institute of Aviation to quickly develop a coaxial rotor prototype applicable in ultra-light unmanned helicopter which has the potential for further improvement of its flight parameters. The article describes the rotor analysis process due to its feasibility based on commercially available solutions, the process of formulating assumptions for the entire structure, MES analysis of the rotor parts all leading to creation of the rotor prototype.

Abstract

The article presents the analysis of anomaly of rotor dynamics in ultra-light helicopter - Robinson R22. Robinson R22 is two-seat, two-blade main rotor and single-engine helicopter, well known as simple and common used aircraft because of low price and high availability. At the same time, large number of accidents and strictly defined rules (recommended piloting technique) and weather condition for safe flight show disadvantages of Robinson R22. The reason for considering this topic is the analysis of different flight properties and helicopter behaviour as well as easy entering into dangerous flight manoeuvre. In the article different flight properties and loss of control during the pull-up, manoeuvre or vertical gusts of wind and mast bumping accidents were analysed. Analysis shows that problem may be caused by construction of three-hinged rotor hub, designed and patented by F. Robinson. Article presents model of rotor hub and review of main rotor and rotor hub construction in light helicopters. Because of number of accidents, caused by the unusual behaviour of Robinson R22, restrictive pilotage rules were introduced: prohibition of flight in certain weather conditions, the necessity of attending additional training conducted by trained instructors. To reduce the probability of an accident a special instruction for specific Robinson R22 properties was created. Moreover, the statistics of accidents resulting from loss of control and review of legal changes caused by Robinson R22 accidents are presented.

Abstract

This article presents the influence of rotor blade airfoil shape on main rotor performances. In this case, we analysed the influence of anti-erosion tape, which is applied to the leading edge of the blade to protect the blades from environmental conditions. In Gyro-Tech Innovation an Aviation Company and Institute of Aviation the independent tests of helicopter and gyroplane main rotors were performed. Research includes: bench tests, on the test stand for dynamic testing of insulated rotors and tests on two flying constructions, gyroplane Cavalon produced by AutoGyro GmbH Company and ultralight helicopter Dynali H3. On the test bench, a two-blade rotor, used in ultralight and unmanned helicopters, was tested. In article, the authors present importance of the proper selection and application of anti-erosion coatings on rotor blades. Discuss the behaviour of the above-mentioned constructions with main rotor blades leading edge covered anti-erosion tape, during flight tests. The results of bench tests, including the comparison of polar curves of the main rotor with anti-erosion coating and without were also presented and discussed.

In the summary of this article among others the solution of technological pocked introduced in the rotor blade, corresponding to the thickness of the anti-erosion tapes, in such way that after tape is applied it does not change the contour of the blade airfoil were presented.

Abstract

In the first part, the article describes the stages of the development of gyroplanes and the influence of wartime policy on the interest in light aircraft. Also presented are links and the possibilities of using gyroplanes in various sectors of the economy. The authors, based on source texts, present the current position of the aviation industry in the Polish economy and attempt to diagnose its development capabilities. As a result, factors responsible for the current condition of the light aviation industry and its links with architecture and urban planning are submitted. The question is posed: what consequences will the development of the aviation industry bring for architecture and urban planning, for the community and the image of 21st century cities?

Abstract

The presence of dioxin-like compounds, such as chlorinated dibenzodioxins, chlorinated dibenzofurans and chlorinated biphenyls, in mainstream cigarette smoke has been investigated for seven cigarette brands covering a range of ‘tar’ deliveries from 1 mg to 14 mg. Adjusted per milligram of total particulate matter (TPM), ultra-light cigarettes had the highest concentrations of toxic equivalents (TEQ) of 10 fg/mg TPM. As the ‘tar’ delivery increased, lower concentration values were found in lights and full-flavor cigarettes. Calculated on the basis of a pack of twenty cigarettes, mainstream smoke from the ultra-lights and lights products produced values around 200 fg TEQ, and the full-flavor brand produced 575 fg TEQ per pack. Levels of TEQ from dioxin-like compounds in the tobacco section of four cigarette brands did not show significant differences and were similar to previous literature findings.

Abstract

Particulate- and gas-phase polycyclic aromatic hydrocarbons (PAHs) were determined in the mainstream smoke (MSS) of 59 manufactured cigarette brands (commercially available brands of unknown tobacco and blend type) with variable ‘tar’ yields and physical/technological characteristics. Depending on the existence/absence of filter, the ‘tar’ yield indicated on the packet, and the cigarette length and diameter, the examined cigarette brands were classified into 15 groups: non filter (NF), high (H), medium (M), light (L), super light (SL), ultra light (UL), one-tar yields (O), 100 mm long cigarettes (H-100, L-100, SL-100, UL-100, O-100), and slim cigarettes (SL-SLIM, UL-SLIM, O-SLIM). Cigarettes were smoked in a reference smoking machine equipped with glass fibre filters for collection of PAHs bound to total particulate matter (TPM), and polyurethane foam plugs (PUF) for collection of gas-phase PAHs. The relationships of gas- and particulate-phase concentrations of PAHs (ng/cig) with the contents of typical MSS components, such as TPM, ‘tar’, nicotine and carbon monoxide were investigated. In addition, the phase partitioning of PAHs in MSS was evaluated in relation to the technological characteristics of cigarettes.

Abstract

A comparative study of the mainstream smoke chemical composition of major brands of cigarettes produced in Greece has been conducted. The concentrations of tar, nicotine, CO and cadmium in the mainstream smoke of 32 cigarette brands were determined. In addition, the concentration of Cd in cigarette tobacco was also measured and the transfer rate of Cd from tobacco to smoke was calculated. Smoking of cigarettes and determination of tar, nicotine and CO were carried out by the ISO standard methods (ISO 8243, 3308, 4387, 10315, 10362, 3402, 8454), while the concentration of Cd was determined by atomic absorption spectrophotometry coupled with a graphite furnace (GF-AAS) after acid digestion of tobacco and total particulate matter (TPM) samples. Results were explained in relation to technical specifications of cigarettes. Depending on the amount of tar, cigarettes were classified into seven groups: non filter (NF), 100 mm long cigarettes (L 100), high (H), medium (M), low (L), super low (SL) and ultra low tar yields (UL). Low concentrations of Cd were found in the tobacco of most cigarette brands (94-572 ng/cig), thus resulting in low Cd concentrations in TPM (2-55 ng/cig). The transfer rates of Cd from cigarette tobacco to TPM ranged from 2 % (UL) up to 12 % (H). Relationships among the measured parameters were investigated by the Spearman correlation analysis. Concentrations of cadmium in TPM were strongly correlated with tar and followed the variation of Cd concentrations in cigarette tobacco. However, this tendency was not observed in ultra light cigarettes probably because of a cigarette ventilation effect. The transfer percentage of Cd in TPM was highly correlated with tar, although it was independent of the initial concentration of Cd in tobacco. Finally, factor analysis showed that concentrations of tar, nicotine, and CO in mainstream smoke were influenced by technical specifications of cigarettes, while concentrations of Cd in TPM were influenced by the initial level of Cd in tobacco.

: Determination on impact strength of AK9 silumin on base of ATND method. Archives of Foundry Engineering , 8 (2008)1, 269-272. [23] J. PEZDA: Mechanical properties of the AK132 alloys determination on the ATND method. Archives of Foundry Engineering , 6 (2008)19, 221-226. [24] J. PEZDA: Crystallization of ultra-light alloys on base of magnesium and lithium. Advances in Manufacturing Science and Technology , 33 (2009)2, 55-64. [25] A. BIAŁOBRZESKI, J. PEZDA: Registration of melting and crystallization process of ultra-light weight MgLi12,5 alloy with use of ATND method

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