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 Specific projects included preparation and inspection of shipboard electronic equipment: provision of technical communications for the flagship USS Mount McKinley (AGC-7), press ships, and instrumentation ships; electromagnetic propagation studies and provision of sonobuoys for pressure recording; telemetering technical data from certain target ships; television recording of wave motion and wave heights; provision of timing signals for most projects (excluding bomb detonation timing signals); and provision of electronics equipment necessary for operation of the drone boats. The types of shipboard electronic equipment that had to be prepared and inspected included radios, radiosondes, radars, Identification Friend or Foe (IFF) systems, sonars, radar repeaters, homing devices, radar beacons, and interior communications systems.

The Electronics Group was berthed aboard Avery Island. USS Coasters Island (AG-74) was designated as an electronics repair ship for this group. Group personnel were evacuated from Bikini Lagoon the day before each shot and returned to the lagoon after each shot. For ABLE, group members were not part of initial boarding teams, but began their inspections when general reboarding was authorized. After BAKER, radioactivity delayed most inspections until mid-August. In fact, on 7 August the Target Inspection Section of the Electronics Group was reberthed aboard USS Fulton (AS-11), and Avery Island returned to the United States with most of the Electronics Group personnel. The Instrument Repair Unit also remained behind aboard Wharton and Haven to repair and maintain radiac instruments (Reference C.9.208, p. 3.43; Reference C.9.190, pp. 192-225).

Army Air Group (Task Group 1.5)

Although not under the control of the DSM, Task Group (TG) 1.5 assisted the DSM in determining the bombs' effects on in-flight aircraft. In addition to its several missions as TG 1.5, this group carried out blast and radiation experiments using B-17 drone and B-29 and F-13 aircraft. The drones were equipped with flight analyzers that recorded acceleration, airspeed, and overpressure. Some data were telemetered by a television arrangement. Upon landing at Enewetak, the instrumentation was removed for analysis. The drones were monitored for radiation and inspected for damage. The B-29 and F-13 aircraft had similar instrumentation except for the television system. Additional information on TG 1.5 is found in Chapter 8.

Table 4 is a tabulation of badging and exposures of personnel in the various groups of the Ship Material and Inspection Division. Since personnel were not badged all the time, these figures should be recognized as a partial statement of potential total exposure for these groups. Dose reconstruction techniques, discussed in Chapter 12, provide a way of estimating total dose figures.

NUCLEAR WEAPON PHENOMENA

The program to measure and record the various effects produced by the ABLE and BAKER nuclear detonations was the responsibility of the Technical Director, who headed the Instrumentation Division. The Instrumentation Division was responsible for measuring and recording weapon diagnostic data (blast, heat, radiation, etc.). The plan to measure and record the weapons' effects

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