WO1993013983A1

WO1993013983A1 - Engine arrangement

Info

Publication number: WO1993013983A1
Application number: PCT/EP1992/000107
Authority: WO
Inventors: Wisting Sven
Original assignee: Wisting Sven
Priority date: 1992-01-17
Filing date: 1992-01-17
Publication date: 1993-07-22

Abstract

An aircraft is described having two engines (4, 5) and couplings between each engine and a respective propulsion means (9, 10) for the aircraft, the engines and the couplings being within a single housing.

Description

ENGINE ARRANGEMENT

This invention relates to an engine arrangement for

<? a vehicle which has particular application to aircraft.

Embodiments of the invention will be described below by way of example with reference to Figs. 1 and 2 of the accompanying drawing which show, diagrammatically, vertical, longitudinal sections through an aircraft and a part of an aircraft respectively.

Referring to the two figures, in which similar parts are indicated by the same reference numeral, there are shown aircraft 1 having, as may be seen from Fig. 1, a forward stabilizer 2, which is sometimes referred to as a forward wing, a foreplane or a canard. A main wing 3, which is sometimes referred to as the mainplane, is mounted towards the rear of the aircraft 1.

Towards the rear of the aircraft, and within the body of the aircraft, there are two engines 4 and 5. The engines 4 and 5 are mounted in line and in tandem and, in the embodiment of Fig. 1, the engines 4 and 5 are opposite to each other about a gear box 6, each thereby tending to offset any torque from the other that would otherwise be passed on to the airframe. The engines 4 and 5 in both embodiments drive propulsion means including two contra-rotating pusher propellers or fans 9 and 10 through separate reduction gear arrangements. In the embodiment of Fig. 1, the gear arragements are housed in the box 6. Dual independent drive shafts 7 and 8, sometimes known as two-spool-type shafts, which are co- axially arranged, drive the propellers or fans 9 and 10 in each embodiment. The propellers or fans 9 and 10, which are arranged about a common axis, can be shrouded, as best shown in Fig. 2.

Fuel for the engines 4 and 5, which is stored in the wing 32, is fed to the engines in the embodiment of Fig. 1 via a feeder tank 12 arranged above a luggage compartment 13. In the embodiment of Fig. 2, the drive from the engine 4 to the inner spool-shaft 7 is via gears 15, 16, a shaft 17 and gears 18, 19, and the drive from the engine 5 to the outer spool-drive 8 is via a shaft 21 and gears 22 and 23. The arrangement of the engines in Fig. 2 allows the lower part 25 of the fuselage to be at a smaller angle to the horizontal, than in Fig. 1. In the particular embodiment of Fig. 2 it is at 15 degrees to the horizontal.

Seats 14 are positioned in front of the engines 4 and 5 and the main wing 3, as illustrated in Fig. 1.

A fin 26, which is shown in Fig. 2 has a trim able high set horizontal tailplane 27 for pitch control and is arranged in a well-known way above and aft of the engines.

The engines 4 and 5 are, in the preferred embodiment, ankel-type rotary engines.

The gearing arrangements in the box 6 between the engines 4 and 5 and the propellers or fans 9 and 10 respectively of Fig. 1 are such that, in case of failure of one engine, the other engine can be engaged to drive both propellers, but normally both propellers operate independently to each other. To suit varying requirements, one or both of the propellers can be featherable and/or reversible. It will be appreciated that in the arrangement of Fig. 2, one engine can be made to drive both propellers, should the other engine fail.

The arrangements described enable an aircraft to be provided in which drag is minimised, yaw, upon the failure of an engine, is rendered non-existent as a result of the drive-train arrangement, and vibration is minimised as a result of using engines without recip¬ rocating parts. The aircraft is inherently stable and stall-resistant due to the forward mounted stabilizer 2. The propulsive efficiency is improved by the use of contra-rotating propellers or fans and by the reduction of drag as a result of the in-board location of the engines, which is made more easy by the arrangement of the engines one behind the other, or in line. Economy and speed are significantly enhanced by the slimming of the airframe as a result of the arrangement of the passenger seating, the engines and the propellers, which, in the particular embodiments described, are housed one behind the other.

It will be understood that, while the invention has been described, by way of example, with reference to particular embodiments, variations and modifications thereof and other embodiments may be made within the scope of the appended claims.

For example, the engines 4 and 5 need not be of the Wankel-type, and other propulsion means for a vehicle than the airscrews or fans 9 and 10 may be employed. It will also be understood that for a vehicle of the hovercraft or air-cushion type, for example, the passenger cabin may be beneath the engine arrangement. It will be noted that in the arrangements shown the engines are one behind the other along the length of the aircraft. However, it is not essential that such an arrangement be adopted. In the embodiment shown in Fig. 2, the engines are on different levels vertically. Other configurations may be adopted. The engines could be positioned one above the other, at the same distance along the length of the vehicle, with the gear box between them, or side by side and with a gear box arranged between them. Such arrangements are parti¬ cularly suitable for ultra light aircraft. It will also be understood that the propulsion means need not be from the rear of the vehicle. The arrangements described can be applied to vehicles with propellers at the front or

^■ft- with propulsion means above the main body, as with helicopters. It will also be understood that although the engines are in a single housing, they may be in separate compartments in the housing, in order to meet safety requirements, for example. The arrangements described can make possible an improvement in safety by enabling vehicles that might otherwise be powered by a single engine to be powered by more than one engine.

Claims

1. An engine arrangement for a vehicle including two engines, two coaxially arranged vehicle propulsion means, and means to couple each engine to a respective one of the propulsion means independently of the coupling between the other engine and its respective propulsion means, the engines and the coupling means being arranged in a single housing.

2. An engine arrangement as claimed in claim 1 in which the coupling means includes a gear box and in which each of the engines is arranged on an opposite side of the gear box from the other.

3. An engine arrangement a"s claimed in either claim 1 or claim 2 in which the coupling means between each one of the engines and its associated propulsion means includes a shaft, each shaft being coaxially arranged with respect to the other.

4. An engine arrangement as claimed in any one of the preceding claims in which there is included means which upon the failure of one engine causes the other engine to drive both propulsion means.

5. An engine arrangement as claimed in any one of the preceding claims in which the engines are arranged one behind the other along the length of the vehicle.

6. An arrangement as claimed in any one of claims 1 to 4 in which the engines are arranged at substantially the same distance along the length of a vehicle, either one above the other, or side by side.