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The study aims to provide a quick-and-robust multifactorial screening technique for early detection of statistically significant effects that could influence a product's life-time performance.

The proposed method takes advantage of saturated fractional factorial designs for organizing the lifetime dataset collection process. Small censored lifetime data are fitted to the Kaplan–Meier model. Low-percentile lifetime behavior that is derived from the fitted model is used to screen for strong effects. A robust surrogate profiler is employed to furnish the predictions.

The methodology is tested on a difficult published case study that involves the eleven-factor screening of an industrial-grade thermostat. The tested thermostat units are use-rate accelerated to expedite the information collection process. The solution that is provided by this new method suggests as many as two active effects at the first decile of the data which improves over a solution provided from more classical methods.

To benchmark the predicted solution with other competing approaches, the results showcase the critical first decile part of the dataset. Moreover, prediction capability is demonstrated for the use-rate acceleration condition.

The technique might be applicable to projects where the early reliability improvement is studied for complex industrial products.

The proposed methodology offers a range of features that aim to make the product reliability profiling process faster and more robust while managing to be less susceptible to assumptions often encountered in classical multi-parameter treatments.

The experience gained since 1959 at MBB, Military Aircraft Division, in the development and flight testing of V/STOL combat aircraft having the capability to reach Mach 2 and to take off with after‐burning temperatures is described. The German project VJ 101 C and the US/FRG project AVS as well as the joint US/FRG V/STOL Technology Programme conducted during the years 1967 through 1970 serve as examples. The paper consists of two main sections:

MODERN HIGH PERFORMANCE AIRCRAFT with large envelopes, a variety of external stores and possibly, variable geometry as well, cannot exhibit sufficient inherent stability (static and dynamic) and conformity of handling qualities without the use of artificial stabilisers. This is especially true for vertical take off and landing aircraft which exhibit either neutral stability or instability during hovering and transition.