A fifth projec.. sponsored by the Diamond Ordnance uze Laboratory, studied the effects of nuclear radiation on electronic fuze components and materials. Electronic components were placed in special test circuits to emphasize the property to be measured. The signals were fed into a mag- netic-tape recorder, which recorded the performance of the components during the detonation. In addition, the telemetering points of a Corporal fuze system were monitored, and departure from normal operating level was recorded on the tape. r were recorded at experimental stations. ED As a result, some noteworthy changes in electronic gear were observed: Some transistor parameters underwent transient changes 84 times their initial value without ensuing permanent damage; plate currents of vacuum tubes changed up to 120 per cent; resistors exhibited decreases in resistance of from 10 to greater than 20 per cent for periods of a millisecond; and the Corporal fuze exhibited dis- turbances ED a strong possibility of firing at neutron doses as low as It may be tentatively concluded that: 1. Almost all electronic components may suffer deleterious effects after a nuclear detonation which cannot be detected by simple measurements. 2. ments. 3. Many transient effects would not have been noted in reactor experiTransient susceptibility was directly dependent on the degree of exposure. . 4. Data from a number of diodes shows that they may be reliably employed to discharge a firing capacitor at the time of a nuclear detonation. 5. A Corporal fuze system would be highly suspect in a nuclear en- vironment. Program 8, Thermal Radiation and Effects 4 ) it was the purpose of the program to (1) study the effects ofa atomic weapons on materials and to evaluate a skin simulant<As substitute for animate skin in these studies; : ) eal a (2) obtain spectroscopic meas- urements of thermal irradiance as a function of time on a high altitude burst; (3) measure the fireball size of a high altitude burst as a function of time by photographic means; (4) obtain a photographic record of the early time spectra of a high altitude burst with high time and spectral resolution; (5) make measurements of the size, persistence, and spectral irradiance of the fireball in the infra-red from a high altitude burst; and (6) study material ablation from specimens inside the fireball, and test the neutron vulnerability of various materials to be used in the Teak and Orange experiments. For the very high altitude event, shot Yucca, two RB-36’s were modi- fied to serve as instrumentation platforms. Special windows and shelves were provided for the instrumentation and special wiring was installed. The aircraft were provided with special radar equipment to track the balloon assem- bly and position themselves. The AOC-CIC aboard the USS Boxer, which also served as the balloon launching platform, was utilized for control and as a back-up positioning system. Both aircraft were well positioned so that all instruments had the burst in their fields of view. Excellent records were obtained by ali projects whose instrumentation was aboard. In addition to its participation on shot Yucca, Project 8.5 also made 34 AFWL/HO 33