Constant flexibility in the service of hi-tech research: Height-adjustable work platforms at DLR

1. The Customer

The Flight Operations department of the German Aerospace Centre (DLR) in Brunswick tests new developments on and inside aircraft under actual (non-virtual) conditions. The range includes aerodynamic studies, in-flight simulators as well as the testing of navigation systems and air traffic management systems. The research contracts come both from the DLR itself and from external universities, national authorities, industry or external research institutes.

In preparatory sessions, often lasting several weeks, the six aircraft and two helicopters are modified to cater for the requirements of the relevant research contract, components are fitted and modifications undertaken. It is only once extensive ground tests have been completed that the operation takes to the skies.

The main medium for conducting the research is a VFW 614 ATTAS (this stands for Advanced Technologies Testing Aircraft System) that is now over 20 years old. For more than two decades it has been flying throughout Europe on DLR test contracts.

2. The Mission

For working on the lateral control system of the VFW 614 ATTAS a height-adjustable working platform needed to be designed. As regards the size requirements for the platform two factors were specified: 1) the width of the height controls that had to fit under the platform and 2) the need for an unencumbered projection distance of at least 1 metre.

The requirements on load capacity were particularly demanding because, in addition to two technicians, material and spares frequently also need to be accommodated on the platform. At the same time, weight savings were called for because the working platform needed to be light enough to be moved by two people without difficulty. This meant a full design specification which was duly drawn up by the DLR.

3. The Solution

In close collaboration with the DLR, ZARGES Aluminium Systems GmbH (ZAS) developed a concept that promised to meet the difficult and sometimes conflicting requirements. Repeated discussions and agreement with everyone involved in the project were called for until the optimum result was finally achieved – in particular as far as the height adjustment facility was concerned. “This was one of the most important pre-requisites for us, to enable us to carry out work on the whole of the side rudder easily and comfortably”, explained Stefan Schröder, the engineer at DLR responsible for new research contracts as well as for technical support inside the aircraft hanger.

The ZARGES height-adjustable working platform replaces the rigid scaffolding previously used, thus considerably simplifying the work. A graduated height adjustment facility means that the height of the 2,20 m x 4,50 m platform can be varied between 3,50 and 7,00 metres.

Maximum load capability has been increased to 300 kilograms so that two people and a wide range of materials can be accommodated on the platform. In the future, the development engineers and technicians will be able to carry out their work on the lateral control system of the ATTAS aircraft conveniently and safely.

4. Special Technical Features

Height adjustment facility:

• Multi-level adjustment facility between 3,50 m and 7,00 m.
• Notches every 50 centimetres.
• Height-adjustable by means of hand crank with corresponding transmission action.
• Specially developed guide profi les for simultaneous increase in stability.

Weight:

• As light a weight as possible was one of the important criteria in the design specifi cation.
• Can be operated by two people without any diffi culty.
• Empty weight of 1260 kg with a load capacity of 300 kg. (Only 40 % of the weight of a steel construction)

Large platform with high load capability and 1,00 metre projection:

• Particularly large working platform (2,20 m x 4,50 m) featuring ample space for spares and tooling.
• Approx. 1,00 m unencumbered projection for maximum possible reach.
• Optimum tilt safety assured due to a broad crossbeam underneath the aircraft.