mppd Posted August 28, 2009 Posted August 28, 2009 As part of the ongoing F-4 packs I'm doing, I'm putting together a 25th TFS pack - this unit flew the first D-model F-4s with tapelights in SEA, and all aircraft had a distinctive fuselage spine antenna offset to one side (and later had the LORAN towelrack antenna added as well). These birds specialized in supporting the Igloo White program and deploting various seismic/acoustic sensors. I'd like to add some of these, but photos are scarce and dimensions even more so. Any help would be appreciated. Thanks, Mike D. Quote
+331Killerbee Posted August 28, 2009 Posted August 28, 2009 ADSIDs The ADSID, or Air Delivered Seismic Intrusion Detector, was a family of sensors that were released from aircraft as the name implies, and fielded in versions I, II and III. Sensors dropped in each area of operations were factory-built with a fixed-frequency on which they transmitted. For any of the area-designated frequencies, they had to be ordered by unique FSN (Federal Stock Number) to match the assigned frequency channels. Nomenclature Model Variant Type Length Weight ADSID I (N) - - - - - - normal - seismic - 31.00 ins - 26.0 lbs ADSID I (S) - MA-36 - short - seismic - 20.10 ins - 13.7 lbs ACOUSID II - TC-415 - ****** - seismic-acoustic - 53.14 ins - 38.8 lbs ACOUSID III - MA-31 - ****** - seismic-acoustic - 47.63 ins - 37.2 lbs ADSID III (N)- MA-33 - normal - seismic - 37.66 ins - 37.2 lbs ADSID III (S)- MA-37 - short - acoustic - 20.10 ins - 13.7 lbs MODS 81 mm - mortar - ****** - seismic - 33.00 ins - 9.6 lbs It is estimated that some 36,000 ADSID and ACOUSID sensors were produced by just one of the contributing manufacturers involved. Sensor design consisted of a series of common modules, using the latest Integrated-Circuit chip technology of the time to keep costs down. The electronics design centered on a concept of interchangeable subsystem circuit boards - 'Common Modules'. Common Modules were cylindrical, sealed in hard foam potting compound, and connected to each other with circular connectors around the outer circumference at the ends of the cylinders. As with the GSID, the same adjustments - Gain, Code, Real-Time, Inhibit, and Disable - could be programmed into the ADSID modules. A 'Common Module' existed for each of the following functions; Transmitter, Encoder, Command decoder, and Command receiver. RF alarm messages were modulated with a combination of 19kHz, 25kHz and 32kHz pulses, which provided up to 27 codes (IDs) on a single radio channel. The transmitter radiated two watts power on one of 40 channels in the 160-175 MHz-band FM/VHF radio spectrum. Presets If switched to the RT (Real Time) mode, the sensor would transmit alarms at a maximum rate of 1.4 per second. If the sensor alarmed constantly in the RT mode, minimum battery life was at least 48 hours. If switched to the INH (Inhibit) mode, the sensor would transmit alarms at a maximum rate of one every ten seconds. Minimum battery life in this mode was 45 days. In spite of rocks, trees, rice paddies and other inhospitable impact sites, 80% of the ADSIDs were found to be operational after air delivery. Application The ADSID III shown in the photograph above is typical of the devices dropped from U.S. aircraft along roads, rivers, and jungle trails in Southeast Asia. They were dropped in sequential 'strings' along a predetermined target line in a series of from 4, up to 10, 12, 15 or sometimes more, depending on the priority of the target area. With their flexible spring-steel antennas, they were designed to bury in the ground and blend into the surrounding foliage by resembling tree branches and plants. All devices transmitted alarm data for only a short distance. They were continuously monitored twenty-four hours a day by U.S. Air Force crewmen flying unarmed, propeller - driven electronic surveillance aircraft orbiting overhead at 20,000ft. Initially, Navy OP-2E Neptune aircraft performed sensor air deliveries at very slow speeds from altitudes as low as 500 feet, making them easy targets for enemy gunfire. The pilots of VO-67 at Nakhon Phanom AB knowingly expected that they would incur as high as an 85% casualty rate from such operations, but volunteered to fly them anyway, and many crewmen were lost. During later operations, sensors were hand-dropped from CH-3 Jolly Green Giant helicopters by personnel of the 21st SOS Dust Devils (Special Operations Squadron) and later, delivered by Air Force F-4D Phantom-IIs. 331KillerBee Quote
mppd Posted August 28, 2009 Author Posted August 28, 2009 Thanks KB, That's more than I had found for dimensions. The photo I had found. I had a feeling that you'd have something on 'em. Thanks again, Mike Quote
Dreamstar Posted August 28, 2009 Posted August 28, 2009 http://en.wikipedia.org/wiki/Operation_Igloo_White Quote
+331Killerbee Posted August 28, 2009 Posted August 28, 2009 The Pod..... The Sensors...... 331KillerBee Quote
mppd Posted August 28, 2009 Author Posted August 28, 2009 BINGO!! Outstanding!! Exactly what I needed - I can't guarantee I'll do every one, but several at any rate. No one else will probably ever fly a mission dropping them anyway... Thanks again, owe you a favor! Mike Quote
+ST0RM Posted August 30, 2009 Posted August 30, 2009 Write them into a Recon mission. Must drop them at the target area, or something like that. Looks to be a great new add-on. Quote
mppd Posted August 30, 2009 Author Posted August 30, 2009 Thanks Storm, but the historical stuff seems to be about as popular as the make-believe stuff for the Third Wire series. I'm just trying to get the USAF F-4 variants done with at least one markings/decal package each before I take a break. The 25th TFS birds were sort of distinctive, so I guess they deserve a separate pack - they received the LORAN "towelrack" in 1971 or so as well. Mike Quote
mppd Posted September 2, 2009 Author Posted September 2, 2009 SUU-42 or -42/A Flare (or sensor...) dispenser - for F-4 or AC-130... Mike Quote
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