Analysis of interference to remote passive microwave sensors

The final acts of the 1979 World Administrative Radio Conference (WARC) were analyzed to determine potential interference to remote passive microwave sensors. Using interferer populations determined from the U.S. Government and FCC Master File Lists and assuming uniform geographical distribution of interferers, the level of interference from shared services and active services in adjacent and subharmonic bands was calculated for each of the 22 passive sensing bands. In addition, due to the theoretically large antennas required for passive sensing, an analysis was performed to determine if smaller antennas, i.e., relaxed resolution requirements, would have an effect on interference and to what extent

Remote sensing frequency sharing studies, tasks 1, 2, 5, and 6

The following tasks are discussed: adjacent and harmonic band analysis; analysis of impact of sensor resolution on interference; development of performance criteria, interference criteria, sharing criteria, and coordination criteria; and spectrum engineering for NASA microwave sensor projects

Fatal General Aviation Accidents in Furtherance of Business (1996–2015): Rates, Risk Factors, and Accident Causes

Introduction: General aviation missions related to furtherance of business potentially carry higher risk (operations in adverse weather, at night, for longer distances) than those undertaken for recreation. The study herein was undertaken to determine fatal accident rates, proportions, and risk factors/causes. Method: The National Transportation Safety Board aviation accident database was queried for accidents (1996–2015). Annual fleet times were from the general aviation annual activity survey. Statistical analyses used Poisson distributions, proportion testing, and Cohen’s Kappa tests. Results: The fatal accident rate for business operations was three- to six-fold lower than the rate for recreational flights with a decline evident between 1996 and 2015. However, a higher proportion of business-related accidents were fatal (33%) compared with recreational flight mishaps (22%). Business-related, fatal accidents were over-represented for operations of longer flight distance, non-daylight hours, and degraded visibility. The most frequent accident cause categories were a deficiency in pilot skills/experience/systems knowledge (45%) and violation of the federal aviation regulations (e.g. departure into instrument conditions without an instrument flight plan, flight into known/forecast icing) (26%). Conclusion: Despite the fatal accident rate declining for business-related missions, the proportion of fatal mishaps was higher than that for recreational flights. Practical application: Towards enhancing safety (a) flight reviews should discuss alternate flight planning to circumvent the hazards of night operations, adverse weather, and fatigue, (b) pilots should be encouraged to participate in additional training, e.g. the FAAST program, and (c) pilots should avail themselves of aviation training devices for maintaining instrument proficiency

Causes and Risk Factors 1 for Fatal Accidents in Non-Commercial Twin Engine Piston General Aviation Aircraft

Accidents in twin-engine aircraft carry a higher risk of fatality compared with single engine aircraft and constitute 9% of all general aviation accidents. The different flight profile (higher airspeed, service ceiling, increased fuel load, and aircraft yaw in engine failure) may make comparable studies on single-engine aircraft accident causes less relevant. The objective of this study was to identify the accident causes for non-commercial operations in twin engine aircraft. A NTSB accident database query for accidents in twin piston engine airplanes of 4-8 seat capacity with a maximum certified weight of 3000-8000lbs. operating under 14CFR Part 91 for the period spanning 2002 and 2012 returned 376 accidents. Accident causes and contributing factors were as per the NTSB final report categories. Total annual flight hour data for the twin engine piston aircraft fleet were obtained from the FAA. Statistical analyses employed Chi Square, Fisher\u27s Exact and logistic regression analysis. Neither the combined fatal/non-fatal accident nor the fatal accident rate declined over the period spanning 2002-2012. Under visual weather conditions, the largest number, n=27, (27%) of fatal accidents was attributed to malfunction with a failure to follow single engine procedures representing the most common contributing factor. In degraded visibility, poor instrument approach procedures resulted in the greatest proportion of fatal crashes. Encountering thunderstorms was the most lethal of all accident causes with all occupants sustaining fatal injuries. At night, a failure to maintain obstacle/terrain clearance was the most common accident cause leading to 36% of fatal crashes. The results of logistic regression showed that operations at night (OR 3.7), off airport landings (OR 14.8) and post-impact fire (OR 7.2) all carried an excess risk of a fatal flight. This study indicates training areas that should receive increased emphasis for twin-engine training/recency. First, increased training should be provided on single engine procedures in the event of an engine failure. Second, more focus should be placed on instrument approaches and recovery from unusual aircraft attitude where visibility is degraded. Third, pilots should be made aware of appropriate speed selection for inadvertent flights in convective weather. Finally, emphasizing the importance of conducting night operations under instrument flight rules with its altitude restrictions should lead to a diminished proportion of accidents attributed to failure to maintain obstacle/terrain clearance

Save and Continue?

The purpose of this thesis is to describe the research I completed and the body of work produced during the course of my Master\u27s studies. The paper begins by briefly recounting early influences and the nature of my practice at the time I began the program. Then elaboration follows on the development of my work across various media, both traditional and digital. The work centers on formal questioning of pictorial media and draws conclusions on the nature of picture making, and the motivations I have for pursuing pictorial art

Passenger Obesity and Regional Aircraft Performance for the Most Corpulent States in the USA

Obesity affects over 25% of Americans; however, prescribed FAA standard passenger weights for US airlines are based on data compiled 15 years ago. Since increased passenger weight degrades aircraft performance and may lead to a loss of control, the hypothesis herein is that passenger weight under-estimation for states with high obesity rates could potentially lead to a runway overrun or the inability to out climb rising terrain. In terms of the employed methodology, current person weights for the ten most obese states were determined using nationwide data adjusted for state ethnicity. Performance degradation for regional aircraft was assessed by accelerate-stop distance for a rejected take-off and climb gradient. Statistical analyses employed Poisson distributions. The results reveal that obesity rates across all ten states increased (p\u3c0.001) between 2000, the year for which data were captured for standard passenger weights, and 2013. Moreover a 5.4 kilogram gain over the standard weight in current usage was evident. Modelling transport-category aircraft performance demonstrated that under-estimating passenger weights could degrade climb performance potentially leading to a collision with rising terrain and/or a runway excursion in the event of a rejected take-off. In conclusion, caution should be exercised in using standard passenger weights for states prone to obesity

General Aviation Accidents Related to Exceedance of Airplane Weight/Center of Gravity Limits

Obesity, affects a third of the US population and its corollary occupant weight adversely impacts safe flight operations. Increased aircraft weight results in longer takeoff/landing distances, degraded climb gradients and airframe failure may occur in turbulence. In this study, the rate, temporal changes, and lethality of accidents in piston-powered, general aviation aircraft related to exceeding the maximum aircraft weight/center of gravity (CG) limits were determined

Preserving Digital Oral Histories

This presentation addresses considerations for preserving audiovisual materials and large file formats

The effects of a seven week slideboard training program

The slideboard is a new exercise device that may provide a form of aerobic exercise. The cardiorespiratory and muscular strength and endurance benefits have not been established. Therefore, the purpose of this study was to determine the changes in leg strength and endurance, aerobic capacity, and body composition, during seven weeks of training on a slideboard. Ten male subjects ages 19-30 (x = 24 {dollar}\pm{dollar} 3) with an above average fitness level, volunteered to participate in this study. The subjects completed a max VO2 treadmill test, strength and endurance tests of knee extension/flexion, hip extension/flexion, and hip adduction/abduction, and skinfold tests for body composition pre and post training. A one way repeated measures analysis of variance (ANOVA) showed significant increases in maximum heart rate (192.9 bpm vs 195.7 bpm, p =.006). Left leg flexion endurance also significantly increased following the training (5.0 sec vs 6.2 sec, p =.0181). There was no significant differences found in any of the other variables measured. For individuals with an above average fitness level between the ages of 19 and 30, a seven week training program using a slide board with the same intensities and durations used in this study did not cause significant changes in cardiorespiratory fitness level or strength and endurance measurements with the exception of left leg flexion endurance