Thomas Q. Carney

An Airborne and Wind Tunnel Evaluation of a Wind Turbulence Measurement System for Aircraft-Based Flux Measurements*

Abstract Although the ability to measure vertical eddy fluxes of gases from aircraft platforms represents an important capability to obtain spatially resolved data, accurate and reliable determination of the turbulent vertical velocity presents a great challenge. A nine-hole hemispherical probe known as the “Best Air Turbulence Probe” (often abbreviated as the “BAT Probe”) is frequently used in aircraft-based flux studies to sense the airflow angles and velocity relative to the aircraft. Instruments such as inertial navigation and global positioning systems allow the measured airflow to be converted into the three-dimensional wind velocity relative to the earth’s surface by taking into account the aircraft’s velocity and orientation. Calibration of the aircraft system has previously been performed primarily through in-flight experiments, where calibration coefficients were determined by performing various flight maneuvers. However, a rigorous test of the BAT Probe in a wind tunnel has not been previously ...

Meso-Synoptic Scale Interactions during AVE/SESAME 1, 10–11 April 1979. Part II: Influence of Convective Activity on Larger Scale Flow

Abstract This is the second of two companion papers that describe the development and application of a unique set of kinetic energy budget equations which account for meso-synoptic scale interactions. This paper applies the set of equations and data discussed in the first paper to examine the influence of organized deep convective activity on larger scale flow during AVE/SESAME I, 10–11 April 1979. Kinetic energy budget results are presented for five areas: the total analysis area; the whole convection area which is fixed and contains most of the convective activity during the 24-h period; and three subareas, one containing the most intense convection (CBI), one containing weaker convection downwind of CB1 (CB2), and one containing essentially no convection downwind of CB2 (NC). Scale interactions arise through the differences between the total SESAME dataset and that based on only the large-scale NWS data (see paper I). These differences are referred to as the δ-scale. The most energetically- active area...

Comparison of Best Economy and Best Power Mixture Settings in the Purdue University Training Fleet Revisited

Best economy (lean of peak or LOP) operation of aircraft engines rather than best power (rich of peak or ROP) has been suggested as a means to reduce fuel consumption in light aircraft with modest speed reduction leading to reduced operating cost (increased miles per gallon), and to reduce cylinder head temperatures (CHTs) leading to improved engine longevity and reduced maintenance cost. A recent study by Chrisman (2011) using a limited number of data sets from aircraft in the Purdue University fleet of Cirrus SR20 training aircraft demonstrated statistically significant reduced fuel consumption and reduced CHT but no statistically definite speed reduction. This study confirms the earlier results for fuel consumption and CHTs using expanded data sets. It suggests that the failure to derive a statistically significant reduction in speed is a consequence of inherent experimental limitations rather than the lack of any reduction.

Meso-Synoptic Scale Interactions during AVE/SESAME I, 10–11 April 1979. Part I: Theoretical Development of Interaction Equations

Abstract This is the first of two companion papers that describe the development and application of a set of kinetic energy budget equations which explicitly account for meso-synoptic scale interactions. The present paper focuses on the theoretical development of the equations and discusses a particular type of dataset to which the equations will be applied in the second paper. The kinetic energy content for the total observable flow (kT) is partitioned into components representing large (synoptic) scales of motion (kL), δ-scales of motion (differences between the total and large-scale flow denoted as kδ), and interactions among features within the two scales. Thus, kT = kL + kδ + (VL·Vδ). The Eulerian form of the kinetic energy budget is derived for each of these components. A Barnes objective analysis scheme is used to obtain two gridded datasets, one of which is based on all the data taken in the AVE/SESAME I regional scale network on 10–11 April 1979. This SES network consisted of 23 NWS and 16 supple...

Differences between Kinetic Energy Budget Terms Derived from SESAME and NWS Data Sets

Abstract Upper air data collected during AVE-SESAME 1, 1200 GMT 10 April 1200 GMT 11 April 1979, are used to detect differences between calculations of kinetic energy budget terms derived from two sets of analyses. Barness objective analysis scheme is used to grid both sets of analyses, one based on all data taken in the regional AVE-SESAME network (SES) and the other based on data taken only at the National Weather Service stations (NWS) within that network. The SES analyses were derived from data taken at 23 NWS stations plus 16 supplementary stations. Four areas are examined: 1) the total analysis area, 2) a smaller fixed area that contains most of the active convection throughout the period, 3) a still smaller, but varying area that contains the strongest convective activity as determined from Manually-Digitized Radar (MDR) data and enhanced IR satellite imagery and 4) another varying small area downstream from the strong convective activity that contains no detectable convection. The most significan...

Risk Perception Analysis of a Small Aircraft Transportation System

This study examines the impact and relationship between demographic factors and risk perceptions toward Small Aircraft Transportation Systems (SATS). The study included 178 participants who responded to an electronic survey administered to Purdue University faculty members and to selected leaders within the Purdue Intercollegiate Athletics department. Participants were surveyed as to their demographic identities including gender, age, academic position, and aviation familiarity, as well as their perceptions of physical, financial, and status risk from a SATS program. Results of this study showed that certain demographic factors are significant predictors of certain SATS travel risk perceptions. Participants’ intentions to travel via SATS also are identified to be a function of their demographic identity. Future research topics are discussed to further validate the results of this study.

Pilot Source Study 2015: A Comparison of Performance at Part 121 Regional Airlines Between Pilots Hired Before the U.S. Congress Passed Public Law 111-216 and Pilots Hired After the Law’s Effective Date

This article is the third in a series of reports called Pilot Source Study 2015. In 2010, when the U.S. Congress considered dramatic changes to airline pilot qualifications, researchers from the ‘‘Pilot Source Study 2010’’ sampled pilots from six regional airlines to investigate how pilots’ backgrounds affected their performance in airline training. In 2012, when the FAA proposed rulemaking to http://dx.doi.org/10.7771/2159-6670.1151 implement Public Law 111-216, the ‘‘Pilot Source Study 2012’’ researchers repeated the study with a new sample of pilots from seven different regional airlines. Data from these two studies were combined into a Pre-Law dataset. On August 1, 2013, the mandates of PL 111-216 became effective, ushering in the Post-Law era. The Pilot Source Study 2015 consists of three articles that cover the 19 U.S. regional airlines operating under 14 CFR Part 121. This report (Article 3) compares pilots’ training outcomes between Pre-Law and PostLaw to determine whether their backgrounds had a stronger or weaker influence on Post-Law outcomes. Background variables were segmented into: (a) educational backgrounds, which occur early when pilots obtain their certificates and (b) experience backgrounds, which occur later when pilots accumulate flight time before applying to a regional airline. When comparing the Pre-Law and Post-Law data, educational backgrounds generally had less effect on airline training outcomes. Experience backgrounds also generally had less effect on airline training outcomes, with these exceptions: (a) previous airline and corporate experience had a more positive effect on extra training events, and (b) previous corporate experience had a more positive effect on completions. In conclusion, the congressionally mandated gap between earning pilot certificates and beginning airline training has reduced the positive effects of pilots’ educational and experience backgrounds.

A Safety Management Model for FAR 141 Approved Flight Schools

The Safety Management Annex (Annex 19), which became applicable in November 2013, consolidates safety management provisions previously contained in six other International Civil Aviation Organization (ICAO) Annexes, and will serve as a resource for overarching state safety management responsibilities. Through Annex 19, ICAO has required that its member states develop and implement safety management systems (SMS) to improve safety. This mandate includes an approved training organization that is exposed to aviation safety risks. In 2015, the FAA published AC 120-92B to provide guidance material for certificate holders operating under FAR 121, to implement and maintain an SMS. This AC may also be used by other aviation service providers interested in voluntarily developing an SMS based on the requirements in 14 Code of Federal Regulations Part 5 (14 CFR Part 5). There are numerous reasons for SMS implementation going beyond simple compliance with international or national guidelines. The most important of these is safety enhancement, because it is an intrinsic requirement of the aviation system. There is a vast body of literature regarding SMS, but none of it suggests a model to a specific service provider. The implementation of an SMS model tailored to FAR 141 approved flight schools has the strong potential to yield safety enhancement, through a structured management system to control risks in operation. The purpose of this study is to develop a safety management model for FAR 141 operators, based on the ICAO SMS outlined in Annex 19, and current FAA requirements and safety protocols, as outlined in AC 120-92B.

VFR-into-IMC Accident Trends: Perceptions of Deficiencies in Training

Pilots who operate under visual flight rules (VFR) and in visual meteorological conditions, who then continue flight into instrument meteorological conditions (IMC), remain as one of the leading causes of fatal aircraft accidents in general aviation. This paper examines past and current research initiatives, in seeking to identify causal factors and gaps in training that lead to VFR-into-IMC aircraft accidents, using a mixed methods approach. The Aircraft Owners and Pilots Association Air Safety Institute database and the National Transportation Safety Board database search engines were used to identify accident reports associated with VFR flight into IMC/deteriorating weather conditions for a 10-year time period (2003 to 2012). A national survey was also conducted to gain deeper insight into the self-identified training deficiencies of pilots. There is evidence that situational awareness is linked to decision-making, and there is a lack of proper training with regards to weather and weather technology concepts, making it difficult for pilots to gain these knowledge areas, skills, and abilities throughout their initial flight training and subsequent experience.

VFR-into-IMC: An Analysis of Two Training Protocols on Weather-Related Posttest Scores

According to the Aircraft Owners and Pilots Association Air Safety Institute, 264 accidents were identified as continued visual flight rules (VFR) into instrument meteorological conditions (IMC), during the past ten years. Approximately 89% of those VFR-into-IMC accidents were fatal, causing hundreds of deaths. VFR-into-IMC has been a major concern for the general aviation community, prompting focused efforts. Research, data analyses, outreach, training, and education are recommended practices to address risks associated with VFR-into-IMC. Researchers of the current study sought to evaluate the cause and effect relationship between two training protocols and weather-related posttest scores. A pretest–posttest experimental design was utilized at two testing locations. Participants were randomly assigned to one of three groups: a control group, an interactive online training group, or an interactive workshop group. An analysis of covariance was used to determine whether there was a significant difference between mean posttest scores among the experimental groups while controlling for pretest scores. The treatments did not appear to significantly increase posttest scores after controlling for pretest scores, at either experiment location. Though the results of this study did not yield anticipated findings, much was learned and potentially helpful to general aviation researchers seeking to mitigate VFR-into-IMC encounters. Recommendations for future research and practices