American Airlines, faced with the need to ground inefficient Boeing 707 airfreighters, opted in 1981 to expand its 747 freighter fleet, add Hercules “hub planes”, and increase hub trucking operations. The Hercules' ability to carry the 10-foot M-l (8×8 cross section) containers, its lift capacity and short haul economics made the aircraft particularly attractive as the hub airfreighter. The hub planes feed 747 freighters at New York, Chicago, and San Juan; they also provide freight-er service to Boston, Cleveland, Port au Prince, Haiti, and Santo Domingo, Dominican Republic. The planes are operated under lease arrangements with Southen Air Transport of Miami, Florida and Transamerica Airlines of Oakland California. American's revenue and cost projections for hub plane operations are being met and the Hercules have proven the best available alernative to the grounded 707 freighters.
Prior to the introduction of the BAC 1–11 aircraft, constant speed generator drives were primarily the hydro-mechanical type; i.e., the engine speed was trimmed by the use of hydraulic devices. The BAC 1–11 has introduced the Plessey CSDS, a pneumatically trimmed unit which assumes the dual role of a CSD and an engine starter. This unit is basically an epicyclic gear train which takes inputs from both the engine and a reversible roots type air motor/blower to drive an A-C generator at a constant speed. This paper will discuss the design, operation, and performance of this unique unit.
SOME POSSIBILITIES for shortening the field length requirements of present-day jet aircraft are: Install leading-edge, high-lift devices which are retrofitable to present-day aircraft. Retrofit — or purchase new — aircraft powered by turbofan engines. These have an inherently higher take-off thrust to cruise thrust ratio than the jets, which vastly improves the take-off acceleration. Use boundary-layer control actuated by turbine discharge gas for immediate consideration in new aircraft engines. Use direct-lift jet engines. These will improve the block speed characteristics of the aircraft and also give vertical take-off and landing capabilities. This paper discusses the advantages of each of these possibilities. The author also describes the problem of airport location within a city, and its effect of total travel time.*
The sources of pollution from aircraft and airports are reviewed, with emphasis placed on the industry's current understanding of the magnitude and control technology applicable to such sources. The progress of industry activity in reducing pollution from aircraft is presented, including on-going research directed at defining the impact, source strength, and applicable control technology. The unknowns and the areas in which research is needed and not currently under way also are identified.