Do School Leaders Have a Shelf Life? Career Stages and Headteacher Performance

This paper explores several issues about school leaders, career stages and performance. It draws upon various pieces of research, including the longitudinal study of secondary heads which began in the early 1980s at the National Foundation for Educational Research (NFER), to raise some key issues about headteachers’ careers, the various stages of headship, and the relationship between length of tenure and school leader performance. The paper concludes with some thoughts regarding the future of headship and what needs to be done to ensure that the quality of leadership remains as good as it should be. If leadership at the apex of organisations is as crucial as all the research and inspection evidence suggests, then what needs to be done to ensure a longer ‘shelf life’ for school leaders and is the notion of a limited or fixed-term contract worth revisiting

Laser space rendezvous and docking tradeoff

A spaceborne laser radar (LADAR) was configured to meet the requirements for rendezvous and docking with a cooperative object in synchronous orbit. The LADAR, configurated using existing pulsed CO2 laser technology and a 1980 system technology baseline, is well suited for the envisioned space tug missions. The performance of a family of candidate LADARS was analyzed. Tradeoff studies as a function of size, weight, and power consumption were carried out for maximum ranges of 50, 100, 200, and 300 nautical miles. The investigation supports the original contention that a rendezvous and docking LADAR can be constructed to offer a cost effective and reliable solution to the envisioned space missions. In fact, the CO2 ladar system offers distinct advantages over other candidate systems

Laser space rendezvous and docking system study continuation

Investigations were made of a configuration for a spaceborne laser radar (ladar) to meet the requirements for rendezvous and docking with a cooperative object in synchronous orbit. An analysis was completed of laser phase locking techniques, while experimental verification was made of pulse repetition frequency and resonant scanning control loops. Data measurements on a satellite mock-up were also made. The investigation supports the original contention that a rendezvous and docking ladar can be configured to offer a cost effective and reliable solution to envisioned space missions