Published online by Cambridge University Press: 28 July 2016
The effort required to produce very accurate supersonic nozzles has suggested the need for criteria from which the order of accuracy required for quantitative experiments can be deduced. The purpose of this note is to indicate a way of obtaining such criteria for measurements of aerodynamic forces, but also to point out that “ sufficiently accurate ” nozzles for such measurements are indeed very difficult to produce and to suggest that a remedy might first be sought in interference corrections.