The co-operation between Hamburg and Delft was intense and far more fruitful than the relationship that had existed with Fokker. Information was transferred quite easily back and forth. The culture of the Germans matched that of Delft very well and the engineers on both sides enjoyed the exciting work on the new material. What was still lacking, however, was a trustworthy industrial partner who was willing to share the risk of producing the Glare material. SLC, with AKZO and ALCOA in the background, was a real industrial partner. The dedication of SLC employees like Bill Evancho, Jim Thomas, Carl Gareshé and Marc Verbruggen was vital for the success of the Glare project, especially for the development of a smooth and mature technology from what was still essentially a laboratory process, and to establish confidence in the material. One could depend on the material deliveries from SLC, which was of the utmost importance for DASA.
However, as we have seen in the previous chapter, AKZO did not have the experience in the aerospace sector and ALCOA was retreating from its initial enthusiasm for the Glare material. In the aerospace business, the subcontractors usually take part of the risk of developing the aircraft and
therefore long-term industrial alliances had to be built in a different way than AKZO was used to in the bulk chemical sector, which was its core business.
Airbus wanted to be sure that Glare would be available for the next thirty years. In 1994/95 the ‘Dolores’ reorganisation took its toll and the work on Glare came to a virtual stop in Germany. Nonetheless some Glare repairs were tested on the barrel and co-operation was taking place with a PhD-student from Delft, Richard Müller, who was studying the behaviour of riveted joints in aluminium and Glare fuselages. Since those riveted joints are usually the critical location where fatigue cracks start to develop, this was very important work. Müller established a database of test work on joints, which proved to be essential for the understanding of the behaviour of Glare joints. Like the other PhD-studies, it was an important piece of the puzzle that was being assembled to show a complete picture of the Glare technology. The PhDs contained the results of the undergraduate students who did their Master’s theses and who were usually guided by one of the PhD-students. Numerous Master’s thesis projects were done in this period.
However, around 1995 it appeared that some further action was necessary in order to prevent the Glare project from fading away in Delft. Students are attracted to projects that are new and fascinating, but after so many years it was difficult to keep the same enthusiasm and flavour of novelty as in the beginning when everything was new and fresh. As we saw in Vogelesang’s inaugural lecture, the university staff also broadened their outlook. It was felt that Delft had a responsibility in the Dutch industrial context and that it would be wise to avoid placing all the bets on Glare. The future of the research group should not depend on the application of one material. On the other hand, Glare offered excellent possibilities for scientific study on physical properties, to do modelling work, and to expand the knowledge base in a way that was also fruitful for other materials. Glare functioned as a kind of stepping stone for general research on different properties. Müller’s PhD-study, for example, was on riveted joints. This ancient technology was already in use by the ancient Greeks and was applied from the start in aluminium aircraft structures, but his study on Glare revealed that a lot was also still unknown even for aluminium, despite all the experience with the technology. The findings of his dissertation were taken up by Airbus in Germany for aluminium before Glare was applied. Therefore, all the efforts of the university group on Glare would certainly not be in vain. The work had led to an increase in knowledge and experience in the behaviour and modelling of aircraft materials, which was useful in general. What also
played a role in the changing situation was that the success of the group in Delft led to growth. An Adhesion Institute was founded and also a Centre on Lightweight structures. The Glare project became one amongst many others.
All these projects were carried out in the lab and the group of people working in the lab was expanding rapidly. This also put the culture of friendship and personal relationships around the coffee table to the test. Delft entered a new period.
France
Van Wimersma was sent to Aérospatiale by SLC for support in 1994.
As a skilled designer, he was able to create a place for himself within the company, even as a foreigner from another company. He started a design study for the application of Glare on the A330 fuselage as a follow-up to the previously successful A320 study that he carried out as an undergraduate student. Although the outcome of the A330 work was quite positive and
indicated a 20% weight saving, the French remained sceptical and reluctant.
The difference with the situation in Germany was that in France, Glare was in the hands of composite specialists who considered carbon to be the way to go. In their opinion, Glare could at best only be a step between aluminium and full carbon composites. In the composites department, the assignment to work on Glare meant a dead end to your career. Five or six French Glare designers responsible for Glare passed by over the years and every time Van Wimersma had to start all over again with the ‘education’ and by creating goodwill. “Glare, à la mer” was the popular saying and the fact that the sound of Glare in French was not so shiny as in English, resembling the word ‘glaire’ (phlegm) in the French language, did not improve matters. “Who wants to make an aircraft of phlegm?”, was one of the jokes he became all too familiar with. Once Van Wimersma accompanied one of his French colleagues, who was responsible for Glare, in a car. While they drove past a churchyard, his colleague quipped: “Look, there is the spot we reserved for burying Glare!” It left Van Wimersma feeling uncomfortable. All the same, the French had to be involved in Glare to keep up with the developments in Germany where progress was fast. In Germany, design studies were done on upper shell panels of the A340 fuselage, which indicated a possible weight saving of 14-17%.
In France the opinion on Glare remained critical. Most of the development effort was put into carbon composite aircraft parts, since this was considered to be the future. In a way, the scepticism made sense since Glare had to be considered as a modified bonded aluminium structure and not as a composite material. On the other hand, the French criticism and their experience with composites also helped Glare. The French critics scrutinised Glare rigorously. The Germans discovered the French to be excellent sparring partners. The presence of different nationalities in Airbus was therefore also a significant asset. It was important that Aérospatiale carried out the first serious cost study on the application of Glare in the A330 aircraft. As a material, Glare was 5 to 10 times more expensive per kilogram than a traditional aluminium alloy and this was an important barrier to overcome. Boeing had never got past it and everybody could use this figure to rule out Glare easily because in the end each beautiful technology has to face economic reality.
Because Glare leads to weight savings, less material is necessary, but this will not close the gap between the aluminium and the Glare structure. The remainder has to be balanced by the reduced operating cost
because of the reduction of fuel burnt due to the lighter structure. However, cost reduction during manufacture was a prime issue. The era in which the application of new materials was performance-driven was over. For the material to be viable, the cost of the Glare structure had to come very close to the aluminium structure. Delft considered this to be possible because the excellent fatigue properties of Glare can make an aircraft structure in Glare simpler than in aluminium. For an aluminium structure, reinforcements have to be added around joints in order to reduce the stress levels and prevent fatigue cracking, while this would not be necessary in Glare. Also the crack stoppers, which are necessary in aluminium because significant fatigue cracks may occur and adequate residual strength has to be assured, are not necessary in Glare.
In Glare, the reduction of parts reduced the production costs of the structure. At the same time the use of the so-called ‘splices’, which were invented at that time to produce large panels, was favourable to Glare, as larger panels imply less expensive joints. Because the maximum sheet width of aluminium was originally 2.5 metres, the Glare sheets had to be connected by riveted joints every 2.5 metres. Splicing meant that the sheets would be connected in the Glare internally by bridging fibre layers and by adding extra aluminium sheets. The limit of the size was now the size of the autoclave, but they were huge. However, all these advantages were never quantified and the cost of the Glare material was still considered by many Airbus engineers to be the main obstacle to application. An extensive cost study which was performed by Aérospatiale with the help of Van Wimersma on the application of Glare on the A330 fuselage indicated that although the material costs of Glare are high, the total, finished cost of a Glare product comes very close to an aluminium product. This definitely proved that Glare should not be produced as a sheet material that has to be shaped and machined into a product as is the case for aluminium, but that Glare has to be produced as a component. It had to be laid up and cured in a curved mould such that after curing a product came out of the autoclave with the right shape for the specific aircraft, including the right local fibre orientations and reinforcements that are necessary. In this way, the number of production steps could be reduced significantly. This layup and curing resembles the much earlier way that Fokker had produced his plywood wings and also the production of the wooden fuselage of the Mosquito by De Havilland. Despite the fact that the French added a lot of extra factors to the cost to include uncertain aspects, this conservative approach led to a positive result for
Glare. Unfortunately the A330 cost study on Glare was never signed and released as an official document by Aérospatiale, probably because the outcome was so unexpected and striking that the senior management was not willing to take the responsibility for it. For the Delft team, however, it certainly was a pleasant surprise.
Van Wimersma’s co-operation with Aérospatiale was nevertheless very intensive and the criticism had proven to be the stimulus needed to achieve the best results. Working for SLC was very stressful in those days.
The constant barrage of questions from customers like the French Aérospatiale and the German company DA called for satisfactory answers, since this was vital for the confidence that the foreign engineers had in the material. Each question had to be treated with the utmost seriousness since it could mean the end of the project. Every time a specific issue came up, or when some important work had to be carried out to convince people, all those at SLC dropped whatever they were working on and pitched in to answer the question. Material was produced, specimens were made, tests were done and reports were written in a time that beat records. Beumler had the impression that a hundred people were working in Delft with dozens of testing machines to produce all that work, but in fact the basis of the project in Delft remained relatively modest. The laboratory in Delft was always able to answer the questions since it was very flexible and therefore able to produce test results fast. Even Aérospatiale was impressed and actually invented a name for the Delft approach: ‘real-time testing’. A question posed to Van Wimersma usually produced a test report within two weeks. Within the aircraft company, a fortnight was not even long enough to make a start on the paperwork to propose testing. Executing a test at Aérospatiale could take a year. The situation at SLC was especially stressful around 1995 because AKZO and ALCOA wanted to put less money into the company. A lot of money had already been spent and still there were no signs of a rapid wide-scale application of Glare. The Dutch Ministry of Economic Affairs had to provide a subsidy to keep the Dutch part of SLC alive. This was just enough to bridge the gap between the work done for Airbus and the growing interest within the company.