Figure 2.4 shows the location of the radio telemetry ground station in relation to Ground
Zere.
Aircraft Operation
The two B-29 aircraft were flown in close formation during the entire mission at 30,000 ft
MSL on a bearing from Ground Zero to the telemetry ground station based on the USS Oakhill.
Neither parachute-borne canisters nor the two aircraft were permitted to enter a cylindrical zone of 5000 ft radius established above Ground Zero, This zone was established because
of important safety factors involved in an atomic air drop. Since the computed canister wind
drift resulted in a target point within the prohibited zone, a drop point 6500 {t southeast of
Ground Zero was determined in order to minimize the slant range to Ground Zero of canisters
Nos. 1 and 2.
Each B-29 aircraft deployed a payload of stx canisters. Aircraft 4135 was early by 27 sec
and aircraft 1833 was early by 20 sec over the target point. Canisters Nos. 1 through 6 were
each deployed 18 sec early. Because of a malfunction of the bomb-bay system, canisters Nos.
$ and 5 were deployed at the time No. 3 was released. Canisters Nos. 7 through 12 were deployed by the salvo switch at H—178 sec owing to the failure of the bomb-bay system.
Figure 2.5 shows the canister array, indicating the intended canister positions compared
with the attained positions.
2.4.2
Canister Operation
Pressure data were recorded from all canisters except Nos. 1, 4, 8, and 12. Thermal data
were recorded from a!l the canisters except Nos. 1, 4, 8, 10, and 12.
Thefirst 28-ft sarachute of canisiers Nos. 1 and 12 failed te open. All other canister dualparachute assemblies were satisfactory. No RF signal wis received from canisters Nos. 4 and
8, probably owing to canister power-supply failure. The thermocouple on canister !- >. 12 was
damaged during deployment. The operation of the triple-parachute assemblies in the six canisters nearest Ground Zero could not be determined; however, no loss of data could be attributed to these assemblies.
2.4.3
Radio Telemetry Operation
The radio telemetry ground station was based on the aftersection of the USS Oakhill, LSD,
located 19.5 nautical miles northeast of Ground Zero.
The canister RF carriers wera recorded from the time of deployment from tke aircraft to
approximately H+3 min,
REFERENCES
1. N. A. Haskell and J. O. Vann, The Measurement of Free-air Atomic Blast Pressures, Oper-
ation Jangle, Project 1.3c, Air Force Cambridge Research Center, April 1952 (reprinted in
Blast and Shock Measurements II, Operation Jangle Report, WT -367).
2. Bendix Aviation Corp.. Operation and Maintenance Instructions for Portable Telemetering
Receiving Station, Report DLM-14, February 1952.
3. Bendix Aviation Corp., Instruction Manual, Y-11600 Telemetering Canister, Report DLM-4.
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