AINGTIP TANK SAMPLING SYSTEM LOADING ae vent VALVE JET FUEL AIR FLOW ate scoop FILTER PAPER SAMPLING PROBE BUL HEAD SS TON CHAMBER arc-3 RADIO SAMPLING PANEL GAS SAMPLE SYSTEM APX-6 [FF ARA-8 OF F-5 AUTO PILOT CABIN PRESSURIZATION FILTER PARTICLE SAMPLER Figure 23. F-84G sampler aircraft, CASTLE. general requirements that were later formalized by the IVY/CASTLE Scien- tific Director and approved by the laboratory. A new emphasis on high- altitude sampling was specified by the sampling project manager; such missions required an aircraft capable of operating at or about 55,000 feet (16.76 km) for at least one-half hour (Reference 29, p. 95). was made in August 1953 to use the same 15 A decision (one was lost during IVY) F~84G aircraft that were used in IVY and two featherweight B-36 aircraft. All the F-84G aircraft were rewired, fitted with new electronics, including a new type gamma intensity rate meter, and ten were equipped with a new gas-sampling device called a "double-squeegee.” 135 The remaining five