Ladder models suggest the existence of a continuum, and thereby blur basic differences COOK, Whether the affected persons are merely interviewed, or whether they participate directly in research decisions, possibly implies completely different social-policy and professional-policy backgrounds and underlying philosophical positions. So-called "early" forms of participation, such as the briefing of professional researchers by those who are affected by the problem under study, can, at most, be described as preparatory joint activities that may facilitate participation in the research project at a later date.
However, the problem with these forms of participation is that they may constitute "pseudo participation. The phenomenon can also be observed in many other research fields, where such "early" forms of participation are abused in order to motivate the affected persons to co-operate and to disclose personal information by giving them the false impression that they have a say in the research process.
To distinguish the various types of participation, we consider it more appropriate to specify the decision-making situations in the research process, and the groups of participants, and to disclose who, with what rights, at what point in time, and with regard to what theme, can participate in decisions. Such a procedure is presented in the present special issue by v. The situation is quite different in the case of research projects controlled by the affected persons themselves—for example, "survivor-controlled research" ROSSO, Here, by definition, the persons who are directly affected participate in all decisions.
However, even in this case, it would appear necessary to specify who, or which group, participates in which decisions, because, here too, there are positions of power and competition between individuals or groups. The fundamental decision not to treat the research partners as objects of research, but rather as co-researchers and knowing subjects with the same rights as the professional researchers, gives rise to a number of questions about the material resources needed for participation.
As a rule, professional researchers receive a salary for their work—although, in academically-driven research, this remuneration is often quite low. Normally, the co-researchers receive—if anything—expenses, and they are expected to make their knowledge available free of charge.
The taken-for-grantedness of this situation must be called into question because co-researchers frequently belong to lower social classes or marginalized groups and have limited material resources at their disposal. This means that such resources must be guaranteed during their participation in the project. The necessity of material support is not limited to the remuneration of direct co-operation in the research process. Rather, people from marginalized, low-income groups also need other forms of material support.
GOEKE and KUBANSKI point out that, besides paying an independence-enhancing research fee, the willingness of persons with disabilities to participate in research projects can be increased by the provision of assistance on site, and barrier-free access.
There is no rule about what material resources should be made available to research partners. It depends on the group in question. Resources provided could include travel expenses, childcare costs, food for participants with special dietary needs, compensation for loss of earnings, etc.
Such support for research partners has, of course, advantages and disadvantages. On the downside, "paid" participation can become a job like any other and can cause people to distance themselves from, or compete with, other community members.
However, what is decisive is that remuneration signalizes social recognition of the value of the individual's contribution to research. If participatory research genuinely aims to put the relationship with research partners on an equal footing, then the socially dominant form of recognition must be used. It should be noted that financial resources for the co-researchers must be allowed for when planning participatory research projects, and that funding bodies must be requested to accept the inclusion of such resources in the financial plan.
In the classical research setting, the relationship between researchers and researched seems to be clearly defined. Basically, it is a non-relationship in which the researcher is, as far as possible, neutral or invisible. Anything else is considered to lead to the distortion of the results or to threaten the internal validity.
This situation changes radically when the relationship between the participants is put on a participatory footing. In this case, the perspectives of the various partners and their differences of opinion are important for the process of discovery; objectivity and neutrality must be replaced by reflective subjectivity.
This calls for willingness on the part of the research partners from the life-world under study to enter into the research process, and the necessary knowledge and ability to participate productively.
An apparent dilemma inherent in participatory research becomes visible here. On the one hand, participatory research aims, in particular, to involve marginalized groups in the production of knowledge and, by so doing, to foster empowerment. On the other hand, these are the very demographic groups who are characterized by a lack of competencies and social capital cf. For this reason, they are deemed also to be lacking the competencies necessary to participate in the research process.
The only way out of this dilemma is to ask who defines these deficits and from what perspective. The answer is obvious: They are defined by representatives of the dominant social group—in this case scientists—who specify the necessary knowledge and ability against the background of their familiar worldview and their methodological requirements.
In this way, research becomes a very demanding task that calls for many competencies. By contrast, the primary aim of participatory research is to give members of marginalized groups a voice, or to enable them to make their voices heard. What counts is that they bring their experiences, their everyday knowledge, and their ability into the research process and thereby gain new perspectives and insights RUSSO, The difference between the academic worldview and that of the research partners from the field is actually an asset which must be exploited in the exploration process.
Therefore, mutual curiosity about the knowledge and ability of those on the "other side" and what one can learn from them is so important. It enables all participants to acquire new roles and tasks that differ clearly from those of "classical" research. This means that all participants must change considerably in the course of the participatory research process—both on a personal and on a cognitive level. And yet, the importance of the individual participant and his or her personal competencies, motivation, etc.
It shapes how we respond within and to the research process. If we have control, it also shapes the research process itself. In participatory research projects, professional researchers acquire new and unfamiliar roles—this is especially evident in the case of user-controlled research.
However, role distribution in participatory research is not static. Rather, it is subject to continual change. This is due not least to the relatively long duration of participatory research projects. Months, or even years, can elapse between the beginning and the end of a project. During this time, various developments occur in the group of research partners that shape the way they relate to each other.
Such changes in the role structure have long been familiar to us from ethnological studies, in which researchers spend a long time in the field. HEEG attempted to capture the temporal sequence of qualitative procedures by using the metaphor of the curriculum vitae. The different stages he describes can be adapted to participatory research as follows: At first, the professional researchers enter the field as "foreigners"; as time goes by they assume the role of "mobilizer," "service provider," "provider of information," and "ally"; eventually they become "patrons"; and, in the best case, they finally become "mentors.
Within the framework of participatory research there are also other challenges that researchers must face. The research themes, and the biographies and social background of the research partners, call for very intensive contact.
However, collaborative research with people who have a history of marginalization is possible only on the basis of trust RATH, This trust must be allowed to develop; it builds on long-term, honest relationships that are characterized by closeness, empathy, and emotional involvement.
Here it is important that researchers show their own emotional reactions. The academic requirements described in detail in Subsection 4. At the present point in time, one can safely say that, in a number of disciplines, scientists who pursue a participatory research project—within the framework of a qualification process, for example—become outsiders in the academic community.
This calls for considerable courage and willingness to swim against the current, and, possibly, to put up with disadvantages. The diversity of requirements and roles demands from the researcher very different competencies and skills, and a high degree of flexibility and reflexivity—things that are not acquired in the course of conventional university education.
In a similar way to the professional researchers, the roles of the non-professional research partners, and the way they perceive participation, change over time.
At first, they may view the research project with anxiety, distrust, and detachment, and see themselves as outsiders who are expected to furnish information as in conventional research processes.
At the same time, they are personally empowered and develop dispositions such as self-confidence, self-assurance, and a feeling of belonging. However, participation in participatory research also calls for specific knowledge and skills—in other words, competencies, which the participants must gradually acquire.
These include, for example, linguistic competencies, the ability to proceed systematically in the research process, communicative skills in dealing with groups, etc. Professional researchers should offer training courses and workshops on these thematic areas see "capacity building" in v.
UNGER, and impart these skills in their everyday dealings with the co-researchers. A key task in this regard is to design training units and choose methodological approaches in such a way that they build on the initial state of knowledge of the participants and develop it further. The development of different roles is not without conflict. In the various phases, the relationships—and all other aspects of the research—must be continually reflected upon, and emerging conflicts must be dealt with jointly.
In participatory research, all participants are involved as knowing subjects who bring their perspectives into the knowledge-production process. The potential of the individual subjects to acquire knowledge is shaped by their biological makeup, their personal and social biography, and their social status.
This calls for a high degree of reflexivity in the sense of self-reflexivity and reflection on the research situation and the research process. This is a particularly important issue for action researchers who are intimately involved with the subject of the research, the context in which it takes place, and others who may be stakeholders in that context. This requires, on the one hand, a safe space with open communication—a "communicative space" see Subsection 3.
On the other hand, it calls for numerous types of support on the part of both the professional researchers and the co-researchers. Therefore, the ability to be responsive to the needs of others, to give them time and space for reflection, etc. Reflection can be focused on different things. Personal reflexivity focuses on personal assumptions, values, experiences, etc. We suggest distinguishing four focuses or types of reflection from which techniques and instruments can be derived that can facilitate reflexivity on the part of participants.
The potential closeness of the research participants, and the type of research theme socially taboo issues such as sexual abuse, experiences in psychiatric institutions, poverty, etc.
Writing from a psycho-analytic perspective, Georges DEVEREUX was one of the first to point out that reflection on such personal ways of reacting can be used as a source of knowledge. Whether a psycho-analytic theory background is needed for this type of reflection is, of course, debatable. However, what is undisputed, in our view, is the fact that, in a participatory research context, it is necessary to disclose such personal dispositions—at least to the extent that they impact collaborative work on the object of research.
Conditions conducive to such openness can be created in group settings—for example, in the widely used focus groups—in which an accepting attitude is fostered BORG et al. However, there appear to be inadequacies in the way such groups are run in practice.
Ideas for improvement could perhaps be gleaned from the various therapeutic and consultation group concepts available. As we pointed out earlier, the different interests of the participants inevitably lead to conflicts in the research group from time to time. This means that the relationships between the group members must also be regularly reflected upon in order to shed light on such conflicts and, if possible, to defuse them.
As far as we are aware, there has been little discussion in the literature about the way in which such group conflicts can be reflected upon and moderated. This is surprising when one considers that there is a rich body of literature on group dynamics. The concept of "theme-centered interaction" TCI proposed by Ruth COHN can be considered an example of an attempt to foster social learning and personality development in a group setting.
When applying TCI, an effort is made to keep all the elements—the theme in question, the conflict in the group, the individual participants, and the political, ecological, and cultural context the "globe" —in view at all times and to reflect upon them.
Following Pierre BOURDIEU's concept of sociological self-reflection , , the social determination of the participating knowing subjects, and of the participatory project, must also be reflected upon.
The focus here is on the social conditions of possibility and the limits of the individual subjects and the participatory research project as a collective knowing subject. It is a question of reflecting on the political, economic, and social context conditions in which the research theme and the research project are embedded. In fact, structural reflection is undertaken in all the articles.
Therefore, it is all the more important that it be recognized as a separate type—and an essential element—of reflective practice in participatory research. This type of reflection is largely consistent with the concept of "epistemological reflexivity" employed by BORG By now, it is accepted also as a quality criterion in qualitative research—especially in ethnology. A considerable number of methodological proposals as to how such reflection can be fostered have already been made. To a certain extent, research with partners to whom the rituals of academic research are alien and unfamiliar—which is frequently the case in participatory research—calls for new methods of data collection.
The question of the "appropriateness of the method to the participants" is particularly relevant here. From a methodological perspective, the involvement of field partners as co-researchers in the data collection process has various advantages and disadvantages, each of which must be carefully considered. One major advantage is that the co-researchers have first-hand knowledge of the field. Therefore, they understand the way people think and may be able to obtain better and faster access to the desired informants.
This facilitates the discovery of "natural codes"—in the grounded theory sense of the word. Methods of data collection should therefore build on the participants' everyday experiences. This makes it easier for them to understand the concrete procedures. However, it means that new methods of data collection must be developed that are appropriate to the concrete research situation and the research partners. The range of methods to be found in the literature is very broad and depends greatly on the research field and the research partners in question.
In our view, therefore, it makes little sense to standardize methods of data collection. Rather, it is necessary to follow the Glaserian dictum: It should also be remembered that, while many people from marginalized groups may have limited verbal communication skills, they have developed other communication strategies.
In recent years, the many possibilities of using visual and performative methods of data collection and representation have been discussed in qualitative social research. These procedures have been documented, for example, in three thematic issues of FQS devoted to 1.
It is therefore not necessary to go into detail here. However, we would stress the point made by RATH that, when choosing methods, the previous experiences of the research partners should be specifically addressed. It can be difficult for people who have never had anything to do with research to understand the various methodological procedures. Therefore, special training programs are needed to enable them to carry out the procedures applied within the framework of the project.
Hella von UNGER reports, for example, that capacity building on the part of research partners represents a core aim in community-based participatory research. It is interesting that, in this way, the participants develop not only specialized competencies required for participation in the research process, but also more general competencies, all of which contribute to personal development.
Despite the aforementioned diversity of data collection methods in participatory research, two procedures appear to be applied very frequently, namely interviews and focus groups. We shall now address certain aspects of these two procedures that are particularly visible in the participative approach but are not often mentioned in discussions on qualitative methods.
The interviews conducted within the framework of participatory research are normally semi-structured—a type frequently used in qualitative research. Experience has shown that, after appropriate training, the various research partners are well able to conduct these interviews—generally in teams of two.
In the participatory research situation, it can be clearly seen that the outcome of an interview must be perceived as a situation-dependent co-construction on the part of the interview partners see McCARTAN et al. This has already been discussed in the qualitative research literature.
The author does not perceive communication between two partners as a dyad, but rather as part of a much larger system of communication. She adapts Haley's system of communication as follows: I the sender , 2. In our view, these considerations are of considerable relevance to participatory research because, here, the virtual presence of the participating community must always be borne in mind. RATH incorporates this notion into her study, although she derives it from a different theoretical background.
In view of the imagined listeners, she contends that an interview is not purely a private conversation between the interview partners, but that it is, in a sense, public. The second instrument that is frequently used within the framework of participatory research is the focus group. This label stands for a lot of different procedures. The common denominator is that a group of different types of research participants is formed, and that these participants are given the opportunity to enter into conversation with each other in a safe setting and to deal with aspects of the project.
It can be said that the focus group is one of the key instruments for the creation of a "communicative space" see Subsection 3. In the best case, all relevant issues are discussed. This open dialog becomes the central starting point for the entire participatory research enterprise. However, focus groups can also assume other tasks. For example, if participants do not hail from the same context, focus groups offer them an opportunity to get to know each other RUSSO, Moreover, together with other methods of data collection, focus groups can make a taboo theme known in the community and "get things moving" there v.
In teams of professionals, they can facilitate frank exchanges between the team members BORG et al. They also frequently serve to collect data because in the open and—ideally—relaxed atmosphere, it is easier to address taboo themes v.
This applies particularly to participatory research because it ensures that the various perspectives flow into the interpretation during the data analysis process and that the research partners gain an insight into the background to their own viewpoints and that of the other members.
It is not surprising, therefore, that a number of authors in the present special issue report that data were analyzed in focus groups together with the research partners BORG et al. For similar reasons, the research findings are also discussed in focus groups.
RUSSO points out that it is possible to validate findings communicatively in focus groups and that other effects can be observed at the same time: Hence focus groups can be considered as an instrument that encourages this process of appropriation.
The representation of participatory research findings also has a number of distinctive features. Above all, the multi-perspectivity and multivocality must be preserved in the representation of the results v.
In traditional academic writing, authors stay in the background. It is considered somewhat unscientific to write a text in the first person. Indeed, in some cases, authors consistently refer to themselves in the third person.
The required distance is symbolized by this third person, and the impression is given that the statements made are "objective.
As a rule, the texts aspire to be unequivocal and to follow scientific logic. In participatory research, by contrast, the various contributions to the results must be clearly visible. In their publication, all participants in the study were given a chance to voice their opinions and positions.
In the present issue, RATH takes a more radical step. She uses poetry to make "the emotional" visible; to highlight the constructed nature of texts; and to challenge the conviction that knowledge derived from academic texts is "certain. However, the representation of the results of participatory research cannot be limited to texts. In order to render the findings understandable to affected persons, to give them a basis for further discussion, and to reach a wide audience, other forms of representation are needed.
When discussing data collection Subsection 4. The application of such procedures in the representation stage, too, can make the research findings easier to understand. Nowadays, participatory research strategies are accepted—or even desired—in many practice contexts. In academia, by contrast, participatory research enjoys much less recognition as a fully fledged research method.
If at all, it is perceived as a strategy in the "context of discovery. Participatory researchers do not formulate hypotheses that can subsequently be tested, and even the research questions emerge only gradually during the process of engagement with the research partners. The closeness between the research partners prevents scientific distance on the part of the academic researchers, who are so entangled with the researched persons that it is not possible to separate the researchers' contribution to the collected data from that of the researched; hence the quality criterion of objectivity cannot be fulfilled.
Exact planning is not possible because the negotiation of the various decisions during the research process prevents the estimation of the duration of the project and the expected findings.
When "classical" quality criteria are applied, the research is not acceptable because it is neither objective, nor reliable, nor is it valid. From the perspective of a methodology that invokes the normative theory of science, these arguments are by all means accurate. Although the standpoint outlined above is more widespread in some disciplines than in others, it dominates the science sector both in the universities, when it comes to assessing theses, dissertations, etc.
This problem is faced by qualitative research in general. However, one outcome of the long-standing debate between the "exact" sciences and the humanities about the "object of science" is that interpretivist methods are increasingly being accepted as a basis for concrete research. This can be seen, for example, from the fact that qualitative approaches enjoy greater acceptance in certain disciplines, for example sociology and ethnology.
That said, the aforementioned closeness between research partners in participatory research—and the skepticism that this provokes from some quarters—means that it has not been able to benefit as much from the increased acceptance as "conventional" qualitative research has done.
The dissolution of the subject-object relationship between the researchers and the researched is a further grave problem for the academic recognition of participatory research. In participatory research projects, the role of active researcher—and knowing subject—is not held by the academic researchers alone but by all the participants, with all the consequences that this brings for data collection, analysis, interpretation, and the publication of the findings.
This leads to considerable acceptance problems when it comes to research funding. These problems start with the tendering period, which is often quite short. As a result, it is not possible to develop the research proposal collaboratively because negotiation processes with affected persons take much longer. In most cases, a reviewer's assessment of the quality of a project is based on the aforementioned nomothetic science model. However, as a result, requirements are imposed that either cannot be fulfilled by participatory research, or that lead to nonsensical restrictions.
This starts with the said research questions, which can be formulated only vaguely or in general terms before the project begins. Other characteristics of participatory research also hamper acceptance. It is scarcely possible to produce an exact timetable because the duration of the negotiation processes among the research partners cannot be accurately forecast. All that is clear is that the overall life-span of such a research project frequently exceeds the normally expected timeframe for funded projects see COOK, Certain items in the finance plan also meet with rejection by funding bodies.
However, such items in the finance plan are frequently rejected by the funders. The situation is similar at the universities, where it is very difficult for a young scientist to submit a thesis or dissertation that employs participatory research strategies. Moreover, it is scarcely possible to produce the exact timetables required by universities.
In addition, the number of reviewers who are in a position to assess such works is limited. This depends, once again, on the discipline in question.
At the present point in time, it is almost impossible to gain a doctorate in psychology in Germany with a thesis based on participatory methodology. The problem of forging an academic career is further aggravated by the fact that projects with research partners who are practitioners or affected persons is much more time-consuming because extensive discussions must be conducted with them. This means that the production of scientific works lasts much longer and, as a result, the researcher's list of publications is shorter.
Moreover, for the reasons stated above, few scholarly journals accept participatory works. Furthermore, marginalized groups are studied more frequently in participatory research projects, and these groups are not the focus of interest of "normal science. And because the Science Citation Index serves as an important indicator of scientific qualification, authors who apply participatory methods are disadvantaged. Overall, it can be noted that the current scientific structure is extremely unfavorable for participatory research projects.
In saying that, it cannot be disputed that it is sometimes very difficult to assess the quality and rigor of participatory projects. For these reasons, it will be very important for the future of participatory research to develop criteria that facilitate the assessment of such projects.
On a more pragmatic level, COOK suggests, for example, that standardized application forms be developed. However, there is undoubtedly considerable need for further development in this regard—and a more intense discussion of quality criteria will be of central importance. The problem of quality criteria for participatory research is regularly raised by a diverse range of stakeholders: In qualitative research, the question of appropriate quality criteria has been discussed at length, and various concepts have been proposed.
This discussion will not be pursued here. However, in our opinion, the question of quality criteria for participatory research reveals a number of underlying fundamental questions that are also of relevance to qualitative research in general. If one proceeds from the assumption that, in participatory research, all the perspectives and voices of the participants should be granted equal rights of expression, and that each group possesses qualitatively different knowledge about the social world under study, then it is to be expected that the participants will also have different views on the quality of the research process and its results.
In our opinion, the question of what constitutes "good" research findings is answered very differently by the various research participants, and also by those who review, assess, use, or read these findings.
This response depends on the system of values and norms to which the particular stakeholders subscribe; on their individual interests; and on the discourse that takes place in the context in question. Therefore, when asked by a stakeholder whether, and to what extent, a concrete project corresponds to its values and interests, the researchers must furnish convincing arguments derived from that stakeholder's own discursive context.
The fact that diverse groups address the quality criteria question highlights the need for a more context-specific analysis of what is understood by "quality" in the sense of a good participatory research project. From the perspective of social constructivism—which can be drawn on here as a meta-theoretical approach GERGER, —the concept of "quality" in the social constructivist sense is a socially defined concept.
The constructions that arise in this way are then binding within the sphere of influence of these institutions or organizations until such time as they are revised.
Within the framework of the present Introduction, we shall briefly demonstrate how this perspective can offer a starting point for tackling the problem of quality criteria in participatory research.
To begin with, one must identify the various institutions and groups of participants to whom the participatory research project is accountable. A review of the literature reveals that one can roughly state that participatory research projects are confronted with the task of demonstrating the quality of their work to such diverse social institutions as: In the course of the history of the western world, science has established itself as the social subsystem that judges whether something is "true," in the sense of correct knowledge.
However, participatory research is accountable to many social institutions for whom the criterion of "truth" in the scientific sense of the word is of only secondary importance. Therefore, from now on we shall not refer to "quality criteria," but rather to justificatory arguments employed in the institutional or contextual discourses in question. We argue that, in the course of social development in the various social spheres of activity, different systems of communication and action with different justificatory norms have evolved.
Therefore, the arguments used by researchers to justify a participatory research project and its findings must correspond to these structures because, otherwise, they will not be accepted.
In everyday research practice, these diverse justificatory requirements lead to considerable difficulties because their systematic dissimilarity is not recognized. Rather, they are experienced as incompatible demands that can scarcely be adequately responded to at the one time. This can be clearly seen in a number of contributions to the present special issue. On the basis of four examples derived from these articles, we shall outline the consequences that such diverse, subsystem-specific justificatory structures have.
It should be borne in mind that the participatory projects presented to scientific committees have been developed against the background of justificatory arguments and, above all, values that come from social contexts that differ greatly from the science world. The resulting justificatory arguments do not correspond to the "classical" quality criteria that can be considered to be a context-specific justificatory argument within the science system.
Therefore, compatibility of the justificatory argument structures in the various discursive contexts can be expected in the long term only if efforts to extend the academic code are successful. Modern twin keels are of high aspect ratio and present less wetted area then a full keel or long fin keel while retaining the steady helm associated with full keels. The twin keels become more effective with increased angle of heel, while a single keel becomes less effective.
Because twin keels cant outward at the tip, the leeward keel becomes more vertical and deeper in the water as the boat heels. The windward keel is working more horizontally creating downward lift that increases righting moment giving more power to carry sail. Also with this cant outward from the vertical, leeway forces water up to the root of the fin as opposed to spilling over the tip in a single keel. Hydrodynamic tests have shown that decreasing end tip loss can double the effectiveness of a fin the sole purpose of keel winglets.
The wave pattern reshapes to reduce the fore and aft crests. At hull speed a hollow forms amidship, but the bilge keels cause a wave to form in this hollow, canceling out the stern wave and giving a flatter wake. To ensure the desired effect is at cruising speed the correct fore and aft placement of the keels and proper proportions must be checked by model testing.
This placement is critical, as the model data shows. Too far forward or too far aft and the resistance will dramatically increase. The deep plunging of an ordinary hull is avoided by the stabilizing action of the fins which are also very effective in dampening out rolling motions. The fins also provide a certain amount of lift to the stern at speed when the hull is upright.
The effect of this lift is to flatten the trim angle, i. Directional stability is markedly enhanced by the fins. This is demonstrated both by tank tests and full size yacht performance.
Speed and fuel consumption under power are better then usual. The prop can work in clear water without being shrouded by the keel and rudder. In the case of the motorsailer we were testing, 85 h.
Also the yacht can be controlled in reverse, which is seldom true of single keel yachts. The rudder areas are smaller for the same reason as the keels. Each rudder is more effective as it works upright, deep in the water.
Both keels and rudders can be asymmetrical more curve on one side than the other like a wing, and tailored to work on their one specific tack. This again makes them more efficient allowing smaller appendages. Windward ability equal to that of an ordinary yacht is achieved on a fixed draft approximately comparable to that of a centerboarder without the problems associated with lifting foils.
Windward performance in rough water is superior because of the roll and pitch dampening abilities of the keels. Stability is equal to that of an ordinary yacht without recourse to extreme beam.
Righting moment and range of stability are at least equal to those of a well designed centerboard yacht of relatively deep fixed draft, because ballast can be placed in each fin the ballast is as low as any keel-centerboarder.
The general advantages of twin keels include the ability to take groundings in a level position. This allows the bottom to be cleaned and painted although the shorter and shorter keels are making this more precarious , without the cost and nuisance of a haul out, as well as being easily shipped without a cradle.
When sailing in shallow water, if one should touch bottom, the boat rights and clears itself. This is possible because twin keels draw more water when heeled than upright, unlike single keel boats which when righted dig themselves in deeper. Research have shown that all the above stated advantages are very real, and that by using current state of the art design practices, twin keel yachts can produce very high performance boats.
In England many production single keel yachts have had twin keel versions added to the production line up which have performed better then their single keel counterparts. In racing circles, no one has ever argued with the superiority of bilge boards essentially lifting bilge keels.
Scows dating back to the beginning of this century have used bilge boards exclusively. In yacht designer Bruce King did a series of bilge board one tonners of which Terrorist was notable. She was so superior that the I. In sailing his bilge boarders Mr. King says there was not a significant difference in performance between one or both boards down. In a cruising yacht the simplicity and lack of interior clutter certainly makes up for any performance difference between lifting and fixed keels.
Indications are, from all work that has been done, that twin keels will perform as well or better in a shallow draft then a centerboarder, and definitely better then a single keeler. The key is in the understanding of the complex hydrodynamics involving the interplay of keels with the hull. Only in the last 20 years have yacht designers began to explore the effects of pressure patterns on hulls.
The relationship of keel volume to hull volume to produce constructive wave interference at the required speed and the correct toe in angle of the keels to align them with streamline flow have more to do with the success or failure of twin keels then anything else.
We tested a model of a 37'-9" motorsailer, first with a deep fin keel 6'-4" and then with shallow draft twin keels 3'-9".
International Journal of Doctoral Studies Volume 11, Cite as: Avella, J. R. (). Delphi panels: Research design, procedures, advantages, and challenges.
The Advantages of Twin Keels. There has been a growing interest in twin keel boats in North directlenders.mlgh some design work has been done here on sail craft of this type, there are more numerous examples in Europe, particularly in Britain.
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