Climate Impact of Hydrogen Aviation: Research on the variations of surface temperature change caused by hydrogen and kerosene combustion aircraft

Concerned about rapidly rising temperatures, international institutions, nations, and companies worldwide examine how to reduce emissions in all economic sectors. Inside the aerospace sector, it is believed that hydrogen technology has the potential to be the best asset to fight global warming. This thesis aims to create and use a methodology to...

Standardized environmental fatigue sequence for the evaluation of composite components in combat aircraft (ENSTAFF = ENvironmental FalSTAFF)

Fatigue life assessment of composite structures in fighter aircraft necessitates testing with both mechanical and environmental loading at both coupon and structural element size levels. Testing facilities to run such tests are now available but environmental fatigue testing is expensive and time consuming. An environmental fatigue loading...

Flight simulator investigation on the approach path parameters for MLS curved approaches

The present flight simulator study has been addressed to the evaluation of the approach path parameters for curved approach paths. A number of seven oblique approach paths has been investigated, varying in both straight final length and oblique angle. The investigation was carried out for various operating minima (decision height, runway visual...

Flight simulator experiments concerning take-off visibility minima

The Working Group on All-Weather Operations of the European Civil Aviation Conference (ECAC) has initiated a study concerning the factors influencing the minium required visibility at take-off. In two special checkout sessions on the KLM Boeing 747 flight simulator, the experimental conditions have been defined for an investigation directed at...

Patch repair of corroded aircraft skin areas

Environmental conditions in Europe are conducive to corrosion attack of aircraft structures. In military aircraft corrosion problems occur especially at countersunk fastener holes. The corrosion is generally removed by grinding. A limited amount of material removal is specified by the aircraft manufacturers, but it is sometimes necessary to...

Low-speed handling qualities of advanced transport aircraft; A comparison of ground-based and in-flight simulator experiments

The tail of the test spectrum: The effect of different approximations of the lower end of a gust load spectrum on crack growth and fatigue life in 7075-T6 and 2024-T3 specimens

The influence of the approximation of the lower end of the load spectrum was investigated by comparative tests using the Basic F-27 test programme and an extended version, containing three times more cycles per flight. Crack growth was studied on notched sheet specimens made of Alclad 202U-T3 and Alclad TOT5-T6. Fatigue life tests were done on...

Prediction of fatigue crack growth rates under variable loading using a simple crack closure model

A model for the prediction of growth rates of fatigue cracks in aluminium alloys subjected to service loading conditions is presented. The model is based on an approximate description of the crack opening behaviour and was applied successfully in an analysis of effects of crack growth acceleration and retardation observed experimentally under...

The effect of visual information on the manual approach and landing

The visual scene is an important source of information for the manual approach and landing task. This study deals with the effect of this information in combination with basic display information on the manual approach performance. In this context, a pre-experimental theoretical analysis has been performed in terms of the optimal control model....

Effects of variations in gust spectrum and ground-load level on fatigue life and crack propagation in 70T5-T6 and 202U-T3 specimens

The effects of systematic variations in mean stress level and in spectrum and ground load severity of a flight simulation test programme have been investigated on riveted specimens (fatigue life) and sheet specimens with central saw cut (crack growth). The fatigue life and crack propagation life in Alclad 202U-T3 compared with Alclad TOT5-T6...

Determination of low-speed longitudinal manoeuvring criteria for transport aircraft with advanced flight control systems

The application of Active Control Technology concepts and in particular the Relaxed Static Stability principle in certain categories of future transport aircraft will lead to the introduction of primary flight control systems incorporating full-time stability augmentation. For this category of transport aircraft adequate handling quality...

NLR test results as a database to be used in a check of crack propagation prediction models: A Garteur activity

The report describes a joint Garteur activity in the field of the prediction of crack propagation under variable amplitude loading. Existing crack propagation models or models under development will be checked with NLR crack propagation data of 202U-T3 Alclad 2 mm sheet material under F-27 Spectrum flight simulation loading. After completion of...

Handling quality criteria development for transport aircraft with fly-by-wire primary flight control systems

The introduction of fly-by-wire primary flight control systems in certain categories of future transport aircraft, makes it highly desirable to initiate further studies into handling quality criteria for future guidance in system design and airworthiness certification. The handling quality criteria for such aircraft must be based on parameters...