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1 – 10 of 153Alik Isyanov, Alexander Lukovnikov and Artur Mirzoyan
– This paper aims to consider main challenges of development of advanced architectures of propulsion systems, i.e. distributed propulsion systems (DPS).
Abstract
Purpose
This paper aims to consider main challenges of development of advanced architectures of propulsion systems, i.e. distributed propulsion systems (DPS).
Design/methodology/approach
This paper is a comparative analysis of different types of DPS.
Findings
Mechanical driving DPS seems as more feasible in near-term outlook, and turboelectric and full electric DPS are imagined feasible in mid- and far-term outlook.
Research limitations/implications
Additional comprehensive numerical and experimental researches are needed to approve the efficiency of DPS.
Practical implications
Possible impact of installation of DPS on aeroplane fuel efficiency are shown.
Originality/value
Application of DPS on long-range aeroplanes is new a engineering solution, which may allow to meet future advanced efficiency goals.
Details
Keywords
VOUGHT SYSTEMS DIVISION of LTV Aerospace Co, is a major subcontractor to Lockheed California Company for design and construction of the wing, empennage, aft body, alighting gear…
Abstract
VOUGHT SYSTEMS DIVISION of LTV Aerospace Co, is a major subcontractor to Lockheed California Company for design and construction of the wing, empennage, aft body, alighting gear, propulsion system installation, stores pylons and all associated systems located within the airframe components of the S3A Viking anti‐submarine aircraft. Further, because of long experience in developing carrier based aircraft for the US Navy, the company was given the added responsibility of assuring carrier suitability characteristics of the airplane. This included development of detailed ground loads and all design criteria for taxi, catapulting and arrestment. VSD is also performing the carrier suitability demonstration programme, now underway at Patuxent River, Md.
These details of British Patent Specifications are taken by permission from ‘Abridgments of Specifications—Patents for Inventions’. Copies of the full specifications are…
Abstract
These details of British Patent Specifications are taken by permission from ‘Abridgments of Specifications—Patents for Inventions’. Copies of the full specifications are obtainable from the Patent Office, 25 Southampton Buildings, London, W.C.2, price 3s. 6d. each.
ON completion of an 88 minute transit flight, a Boeing 747–436 was landed at night at Bangkok where the temperature was 29°C. The approach was made at a weight of 254 tonnes with…
Abstract
ON completion of an 88 minute transit flight, a Boeing 747–436 was landed at night at Bangkok where the temperature was 29°C. The approach was made at a weight of 254 tonnes with the commander handling, a Vref of 150kt, medium autobrake selection (level three) and a tail wind component of 5kt. After touchdown at 156 kt CAS, the first officer selected partial reverse thrust on all engines but had slight problems engaging reverse thrust on the outboard pair. The thrust reversers on the inboard engines deployed 11 seconds after touchdown; those on the outboard engines deployed 1.7 seconds later. Reverse thrust was modulated during the landing rollout and maintained for a total of 33 seconds. In appreciation of the modest additional stopping distance required by the delayed onset of reverse thrust the commander decided to override the autobrakes and brake manually, leaving the runway at 16kt groundspeed at the last exit point before the runway end. While taxying‐in the crew were alerted by the EICAS to an abnormally hot brake on the number 8 wheel (left body gear, rear inboard wheel). The brake temperature had reached level five on a scale of zero to nine.
FOR a number of years now it has been evident that a successor to the well‐tried Vickers Viscount and Convoir 240/340/440 series was required. However, the big problem was to…
Abstract
FOR a number of years now it has been evident that a successor to the well‐tried Vickers Viscount and Convoir 240/340/440 series was required. However, the big problem was to design an aircraft such that its economics and passengerappealweresub‐stantially better than the machines it would ultimately replace. Other important factors which had to be con‐sidered were improved reliability, easier and cheaper maintenance, higher standards of safety and means of reducing ramp times. Furthermore, the difficult choice of passenger capacity and cruising speed had to be made. Probably the easiest decision was to employ the twin‐engine configuration with the power plants placed in the now familiar rear position, one on cither side of the fuselage.
FUEL SYSTEM GENERALTHE standard version or the F.28 has a conventional two‐tank fuel system with an integral tank in each outer wing section contained by the wing torsion box with…
Abstract
FUEL SYSTEM GENERALTHE standard version or the F.28 has a conventional two‐tank fuel system with an integral tank in each outer wing section contained by the wing torsion box with a total capacity of 2,170 Imp. gal. or 17,200 lb. of fuel. The centre wing torsion‐box pro‐vides space for additional bladder type tanks with a capacity varying from 312 to 700 Imp. gal. or 2,460 to 5,500 lb. as desired.
THE Rainbow is the commercial adaptation of the XF‐12 photographic aeroplane the Republic Aviation Corporation completed for the Army Air Forces. In 1943, the Photographic Section…
Abstract
THE Rainbow is the commercial adaptation of the XF‐12 photographic aeroplane the Republic Aviation Corporation completed for the Army Air Forces. In 1943, the Photographic Section of the A.A.F. issued specifications for a new multi‐engined, long‐range, high‐speed, reconnaissance aeroplane to fly at very high altitudes. The required performance was so much beyond anything in existence at the time that it posed a real problem to designers of high performance aeroplanes. Republic engineers, who for years had specialized in high‐altitude, high‐speed pursuit planes, eagerly accepted the challenge. After exhaustive studies it was found that the performance required by the specification could only be met with a four‐engined machine using Pratt and Whitney R‐4360 engines, supercharged to carry full military power to 40,000 ft. Other combinations would either fail in speed, or in range, or in desired rate of climb or ceiling. A proposal based on four 4360 engines was submitted to the A.A.F., and in March 1944, the Company was awarded a contract for two XF‐12 aircraft. The first prototype was completed in December, 1945, and made its first flight on February 4, 1946.
Fernando Tejero, David MacManus, Jesús Matesanz García, Avery Swarthout and Christopher Sheaf
Relative to in-service aero-engines, the bypass ratio of future civil architectures may increase further. If traditional design rules are applied to these new configurations and…
Abstract
Purpose
Relative to in-service aero-engines, the bypass ratio of future civil architectures may increase further. If traditional design rules are applied to these new configurations and the housing components are scaled, then it is expected that the overall weight, nacelle drag and the effects of aircraft integration will increase. For this reason, the next generation of civil turbofan engines may use compact nacelles to maximise the benefits from the new engine cycles. The purpose of this paper is to present a multi-level design and optimisation process for future civil aero-engines.
Design/methodology/approach
An initial set of multi-point, multi-objective optimisations for axisymmetric configurations are carried out to identify the trade-off between intake and fancowl bulk parameters of highlight radius and nacelle length on nacelle drag. Having identified the likely optimal part of the design space, a set of computationally expensive optimisations for three-dimensional non-axisymmetric configurations is performed. The process includes cruise- and windmilling-type operating conditions to ensure aerodynamic robustness of the downselected configurations.
Findings
Relative to a conventional aero-engine nacelle, the developed process yielded a compact aero-engine configuration with mid-cruise drag reduction of approximately 1.6% of the nominal standard net thrust.
Originality/value
The multi-point, multi-objective optimisation is carried out with a mixture of regression and classification functions to ensure aerodynamic robustness of the downselected configurations. The developed computational approach enables the optimisation of future civil aero-engine nacelles that target a reduction of the overall fuel consumption.
Details
Keywords
Two DC 10–30 aircraft are now in full operation with British Caledonian Airways, the first having commenced operations with the airline in March this year and the other in May…
Abstract
Two DC 10–30 aircraft are now in full operation with British Caledonian Airways, the first having commenced operations with the airline in March this year and the other in May. The decision for BCAL to acquire wide‐body equipment had to be made on the basis that the in‐service date would be commercially right for the airline, and involved factors such as operating patterns, fleet size and market growth. Three types were initially considered; the Lockheed TriStar 1011–500, Boeing 747, and the DC 10–30. At the time that the decision was made (mid‐1976), it was apparent that the TriStar‐500 could only be considered further if the go‐ahead decision was assured, and the ‐100 proposed as an interim type was considered to fit in reasonably with BCAL's plans. The Boeing 747 SP was thought to provide too much capacity for the immediate and foreseeable requirements of the airline, and was more expensive. The final decision to acquire two DC 10's was taken in July last year, the deal also involving the option to acquire a further two aircraft at a later date.
Last month we published a critical review of an American airliner. When we received this we felt that it would be of interest to our readers to publish a similar review of a…
Abstract
Last month we published a critical review of an American airliner. When we received this we felt that it would be of interest to our readers to publish a similar review of a British airliner in very much the same category. We therefore approached Airspeed, a member of whose staff prepared this ‘unofficial’ article for us, setting out as objectively as possible the principal features of the Ambassador and explaining the the reasons behind their adoption.—EDITOR.