Haul Air Transportation Research Articles

Strategy for 19-seat hybrid-electric short haul air transportation

This paper addresses a way to implement greener aviation technologies, such as hybrid-electric propulsion, into the air transportation network to respond to the increasing environmental challenges posed by growing air traffic. New routes could be established between small airports to ensure better air connectivity in Europe while also connecting disadvantaged areas and relieve congestion at hub airports. Such routes could, for example, be served by micro feeder or 19-seat hybrid-electric aircraft, which produce low or no emissions, have lower operating costs, and are more applicable to environmental constraints. To achieve this and overcome the various challenges posed by the new hybrid-electric technologies, a new strategic roadmap for short-haul air transport is needed to optimize network services with small hybrid-electric aircraft.

The Effect of Refueling Stop on Long Haul Air Transport Greenhouse Emissions

A study on the environmental impact and fuel consumption of a long haul aircraft has been performed. Target of the study is to investigate the beneficial effect of refueling in long range flights, in terms of fuel consumption and CO2 emissions, while taking into account the adverse effect on flight duration. This has been achieved using the ‘Hermes’ aircraft performance model, developed at Cranfield University. In a further step, a parametric study has been performed in order to take into account non ideal conditions, where the refueling station is positioned further than mid-distance and extra range is required to be flown. Such data can be useful for scheduling real-life missions featuring refueling stops. The results show that the viability limit is affected by both type of the aircraft and payload, while a minimum range exists, under which the beneficial effect of refueling diminishes.

Advanced short haul aircraft for high density markets

The short haul (less than 500 miles) passenger enplanements represent about 50% of the total domestic enplanements. These can be distinguished by the annual passenger flow for a given city pair and classified into low, medium and high density markets. NASA studies have investigated various advanced short haul aircraft concepts that have potential application in these three market areas. Although advanced operational techniques impact all market densities, advanced vehicle design concepts such as RTOL, STOL and VTOL have the largest impact in the high density markets. This paper summarizes the results of NASA sponsored high density short haul air transportation systems studies and briefly reviews NASA sponsored advanced VTOL conceptual aircraft design studies. Trends in vehicle characteristics and operational requirements will be indicated in addition to economic suitability and impact on the community.

V/STOL Concepts in Short Haul Air Transport

The relative merits of aircraft designed to field length ranging from 0 ft to 3,000 ft are assessed with respect to direct operating cost, indirect operating cost and V/STOL port amortization combined into a total ticket cost for profitable space and other concessions. Tilt wing, V/STOL turboprop STOL and turbofan STOL aircraft operations are examined. The aircraft are of 90 passenger capacity and an average stage length of 200 miles is assumed. A daily traffic flow of, from 500 arriving passengers at a suburban terminal, to 12,000 at a city terminal is considered. It is concluded that: (1) ticket cost will not be greatly influenced by the number or length of runways or vehicle type for suburban operations alone; and (2) number and length of runways has a considerable impact on ticket cost for close-to-city center operations; there being a distinct advantage for aircraft with less than 1,000 ft takeoff and landing distance.

The Potential and Development of a V/S.T.O.L. Inter‐city Airliner

IN a previous article (Ref. 1, 1966), Chichester‐Miles of H.S.A. discussed some of the advantages and opportunities offered by the use of V.T.O.L. aircraft in short haul air transport. In a more recent article (Ref. 2, 1969), Boorer and Davey of B.A.C. reviewed the characteristics and some of the operational problems of V/S.T.O.L. aircraft, and argued in favour of initial civil S.T.O.L. aircraft leading to V.T.O.L. developments as an effective part of the overall ground and air transport system of the 1970s, on the basis of a foreseeable market demand for such aircraft at ranges between 50 and 300 miles. Quoting from their conclusions: ‘S.T.O.L. commercial operations appear therefore to be just around the corner. V.T.O.L. commercial operations may be a decade or so away but, as and when a S.T.O.L. inter‐city transport system develops, the improvement of S.T.O.L. performance toward V.T.O.L. may well become attractive and perhaps even necessary.’