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The purpose of this paper is to augment heat transfer rates of traditional rib-elements with minimal pressure drop penalties.

The novel geometries in the present research are conventional cylindrical ribs with rounded transitions to the adjacent flat surfaces and with modifications at their bases. All turbulent fluid flow and heat transfer results are presented using computation fluid dynamics with a validated v2f turbulence closure model. Turbulent flow characteristics and heat transfer performances in square channels with improved ribbed structures are numerically analyzed in this research work.

Based on the results, it is found that rounded transition cylindrical ribs have a large advantage over the conventional ribs in both enhancing heat transfer and reducing pressure loss penalty. In addition, cylindrical ribs increase the flow impingement at the upstream of the ribs, which will effectively increase the high heat transfer areas. The design of rounded transition cylindrical ribs and grooves will be an effective way to improve heat transfer enhancement and overall thermal performance of internal channels within blade cooling.

The novel geometries in this research are conventional cylindrical ribs with rounded transitions to the adjacent flat surfaces and with modifications at their bases. The combination of cylindrical ribs and grooves to manipulate the turbulent flow.

THIS paper is an analysis of production problems of airframes considering them as problems of structural design. Its object is to suggest new theories for the analysis of air load shears, to point out the extent to which existing conventional designs can be simplified, and to encourage the aircraft industry to direct attention to similar problems concerning the basic arrangement of airframes.

A description of the design philosophy pursued for the principal load carrying structures, materials employed and details of the structural test programme. THE structural concept of the F.28 Fellowship is based on principles that have proven their soundness during the extensive static and fatigue testing as well as during about 2½ million world‐wide operational flying hours of the F.27 Friendship.

THE AIRCRAFT MANUFACTURER can provide helpful answers to the two most important questions of the communities affected by air transportation. Aircraft will be built which do not intrude on the every day existence of communities. Aircraft will be built whose airports only require tens of acres of land instead of thousands of acres. The DHC‐7 will be the first of them.

THE first practical application of a simplified form of aircraft structure was made by the Republic Aircraft Corp. in their production of the Seabee. This machine dispensed with conventional ribs and used external chordwise corrugations instead. These were found to be perfectly satisfactory; they resisted the air loading and were stiff enough to prevent undue distortion of the cross‐section of the structure. For machines of higher speed, however, these corrugations, or ‘beads’ as they were called, would be objectionable and would have to be replaced by internal stiffeners fixed to the skin. This is the type of structure it is now proposed to analyse—a general view is shown in FIG. 1.

Describes preliminary structural design work on a notional uninhabited tactical aircraft (UTA), carried out at Cranfield University. UTAs are seen as an important future element of military fleets. A notional baseline requirement was derived, leading to the evolution of a design solution. The basic requirements for such a UTA are naturally highly classified but, although industry has been hesitant to comment, the baseline requirements and design solution developed herein are believed to be reasonable.

In this article the requirement leading to the design is discussed and this is followed by a general description of the aircraft and its operating efficiency. The accommodation is described, with particular reference to the flight deck and equipment. The various systems and installations are next reviewed; followed by a detailed description of the various structural components, which, in many cases, have been designed round these systems. The development work that has been done in order to allow design and construction to be completed will be described in some detail in a later article.

THE structural design is based where possible on the principles developed over the years on aircraft such as the Trident and Caravelle, and on a scries of investigations and tests carried out to establish weight and cost effectiveness. The design concept is in accoradnce with FAR25 as well as the special requirements defined by the French and German airworthiness authorities.

THE Short SD3‐30 is a wide‐bodied Feederliner optimised for commuter and regional air services. The aircraft has been designed to accommodate up to 30 passengers with baggage plus 3 crew or 7500 lb of freight (3400 kg) and thus conforms with the new Part 298 Regulation of the United States Civil Aeronautics Board. Its operating economics are optimum over sectors of 100 to 300 nautical miles (185 km to 555 km). A large forward loading door capable of accepting ‘D’ size containers is available which facilitates use of the aircraft in mixed passenger/freight configurations. The aircraft will be fully certificated to US Federal Aviation Regulations Part 25 and to British Civil Airworthiness Requirements Group A category.

A Summary by Dr. Alexander Klemin of the Papers Presented Before the Fourteenth Meeting of the Institute held at Columbia University, New York, on January 29–31, 1946. AERODYNAMICS IN spite of increased wing loadings, the use of full span wing flaps has been delayed, because of inability to find a suitable aileron. The Development of a Lateral‐Control System for use with Large‐Span Flaps by I. L. Ashkenas (Northrop Aircraft), outlines the various steps in the aerodynamic development of a retractable aileron system well adapted to the full span flap and successfully employed on the Northrop P‐61. Included is a discussion of the basic data used, the design calculations made, and the effect of structural and mechanical considerations. Changes made as a result of preliminary flight tests are discussed and the final flight‐test results are presented. It is concluded that the use of this retractable aileron system has, in addition to the basic advantage of increased flap span, the following desirable control characteristics: (a) favourable yawing moments, (b) low wing‐torsional loads, (c) small pilot forces, even at high speed.