Type 91 Japanese Torpedo Gyroscope. All Original Box and Precision Adjustments

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Type 91 Japanese Torpedo Gyroscope. All Original Box and Precision Adjustments:
$13500.00

All original, non-restored type 91 Japanese gyroscope manufactured by Mitsubishi at Hiroshima Machinery Works. This is an incredible example of the gyroscope used in the type 91 dropped in the Pearl Harbor attack of 1941. Included is an all original crate from Mitsubishi as well as the precision tuning kit. Everything on the gyroscope mechanically is 100%. The box is fully functional with the writing and labeling still intact with the key. Any questions can be answered by Henry via message.
PLEASE CONTACT ME FOR MORE PHOTOS/ VIDEOS. limits what can be put in the ad.Cleaning is available before shipping. This gyro has never been polished or cleaned, but the marine brass would clean up extremely well.
Here are some key facts and details about the Type 91 Japanese torpedo gyroscope:
1. Historical Significance: The Type 91 gyroscope was integral to the guidance system of the Type 91 torpedo, the primary aerial torpedoes used by the Imperial Japanese Navy during World War II. Its design was pivotal in enhancing the accuracy and reliability of torpedo strikes.2. Usage: The Type 91 torpedo was notably employed during significant naval battles and operations, including the attack on Pearl Harbor and other critical engagements in the Pacific Theater.3. Technical Design: The gyroscope helped maintain the stability and course of the torpedo after it was launched, allowing it to track its target effectively. This technology represented advanced engineering for its time.4. Survivability: Many components of World War II weapons systems were destroyed or lost over time, making surviving examples of the Type 91 gyroscope extremely rare.5. Complete Sets: Complete sets that include the gyroscope, original box, and adjustment kit are particularly scarce and highly sought after by collectors and museums.6. Anti-Rolling Controller (1939–1941): This ground-breaking addition to the Modification 2 variant used dynamic gyroscopic response to control hydraulic pistons. It deflected roll rudders up to ±22.5 degrees to counter tilt and prevent circular runs upon water entry.7. No Electronics Required: The system was entirely mechanical; air entered the device to spin the gyro, which experienced precession if the torpedo veered, subsequently directing pressurized air to the rudder servos to correct its path.8. Gyrocompass Guidance: A dedicated gyrocompass controlled the vertical rudders to ensure the torpedo traveled in a perfectly straight line, while a separate depth-keeping gyroscope adjusted the horizontal tail rudders to regulate depth (typically set between 2 and 16 meters).9. Drop Stability: This gyroscope configuration was vital for the Pearl Harbor attack. It allowed Japanese aircraft to drop the torpedoes from 66 feet (20 meters) in the air at speeds up to 185 mph without the weapons plummeting into the harbor mud.Price Breakdown Factors
• The Gyroscope ($3,000 - $5,000): The core brass and steel assembly is highly prized by advanced mechanical and naval collectors.
• The Original Box & Labeling ($2,000 - $4,000): Period-correct Japanese crates with intact kanji labels and internal
paperwork drastically drive up the premium.
• Air Adjustment Tools ($2,500 - $6,000): Because support tools were usually separated, lost, or scrapped, these are often rarer than the torpedo components themselves.