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This paper aims to develop a new method of fuselage drag optimization that can obtain results faster than the conventional methods based on full computational fluid dynamics (CFD) calculations and can be used to improve the efficiency of preliminary design.

An efficient method for helicopter fuselage shape optimization based on surrogate-based optimization is presented. Two numerical simulation methods are applied in different stages of optimization according to their relative advantages. The fast panel method is used to calculate the sample data to save calculation time for a large number of sample points. The initial solution is obtained by combining the Kriging surrogate model and the multi-island genetic algorithm. Then, the accuracy of the solution is determined by using the infill criteria based on CFD corrections. A parametric model of the fuselage is established by several characteristic sections and guiding curves.

It is demonstrated that this method can greatly reduce the calculation time while ensuring a high accuracy in the XH-59A helicopter example. The drag coefficient of the optimized fuselage is reduced by 13.3%. Because of the use of different calculation methods for samples, this novel method reduces the total calculation time by almost fourfold compared with full CFD calculations.

To the best of the authors’ knowledge, this is the first study to provide a novel method of fuselage drag optimization by combining different numerical simulation methods. Some suggestions on fuselage shape optimization are given for the XH-59A example.

The purpose of this article is to understand alternative African futures as an aid to improved decision‐making and action by governments and by other key agents and stakeholders.

The authors aim is to put the two concepts (“futures” and think tank) into context and explain how they are going to be used in this paper. The aim is not to engage on a prediction exercise about African futures but rather to understand, think about and explore long‐term trends and how they may impact on alternative African futures.

The journey towards a knowledge economy is a difficult one and the experiences elsewhere in the world show that governments on their own can not succeed without assistance from think tanks. This means that as African governments are trying to map out new visions for the future, think tanks can grab the opportunities provided by the current realities to continue playing a meaningful role in shaping African futures.

Africa's complex challenges demand the best of intellectual capacities. Think tanks are potentially one of the best‐suited organizations to develop innovative and advanced solutions to Africa's challenges. They have a special role to play in shaping African futures, both as knowledge providers and policy formulation partners.