Grumman AF-3F Guardian externally-mounted retractable ASQ-8 MAD boom question


Seek out and close with the enemy
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May 22, 2006
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G'day all

I have a technical question if I may in relation to the Grumman AF-3F Guardian and the fitting of its externally-mounted retractable ASQ-8 Magnetic Anomaly Detector (MAD) boom "scabbed" onto the starboard (right) side of it's fuselage, to make it a more effective submarine killer.
In an article I've read by Tommy H. Thomason (
Tommy H. Thomason states that due to the added weight and space required (and I dare say drag) of fitting the MAD system and the large APS-31B surface-search radar under the right wing "required removal of some equipment and stores capability, " as well as a reduction of onboard fuel, which intern reduced the AF-3S's endurance from six to five hours.

My question of curiosity is just how big and heavy was this ASQ-8 MAD system?
For although the MAD boom seems obvious, how much and how big was the actual technical/systems/componentry of this ASQ-8 within the aircraft itself?

Did the 'unseen' internal technical/systems - 'black boxes' of MAD get smaller/more compact and lighter by the 1960's?

The reason I'm asking this is related to my curiosity as to whether such externally-mounted/scabbed retractable Magnetic Anomaly Detector (MAD) would be viable as a capability upgrade to other/existing ASW aircraft like the Breguet Be.1050 Alize for example.



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Feb 11, 2007
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It's not just weight that's significant, the weight of the boom is being added at the rear of the aircraft, giving it a longer moment arm in terms of displacing CofG. Just as you don't want to add weight high up in a ship you don't want to add weight at either end of an aircraft, at least without compensating for it. If you want to retain the CofG where it is and add X Kg at the tail, then you need to remove X Kg at the tail, or 2X Kg at half the distance between tail and CofG, and so on. This may be the primary reason for the reduced endurance, not drag, they're potentially leaving the aft-most fuel tank either empty or only part full in order to keep the CofG range within limits.