SMS Pylon Decoder Unit, Type C

Technical Information

Catalogue No: C0564
Category: Stores/Weapon Management
Object Type: Signal/Data Processor
Object Name: SMS Pylon Decoder Unit, Type C
Part No: 32-010-03
Serial No: 5213
Manufacturer: Marconi Avionics
Division: Unknown
Platform(s): Tornado 
Year of Manufacture:
Width (mm):
Height (mm):
Depth (mm):
Weight (g):
Location: Archive Object Store

Marconi Avionics
PDU Type C
Part No. 32-010-03
Ser. No. 5213
Spec SP.P.80012
Design Code K0656
Mfg. Code
NATO Stock No.


The stores-management system (SMS) controls the selection, arming, and release of the Tornado’s bombs, rockets, guns and guided weapons and times the release in accordance with target data, wind, type of weapon, and other inputs.. Emergency and selective jettison facilities are also provided.

The system consists of four distinct unit types, which are interconnected by means of digital data transmission. As well as the two control panels, there is a master computer and stores loaded unit and numerous decoder units. These latter are responsible for digital data transmission interfaces, and for providing the power signals for stores release. In addition there are wing mounted Pilot Indicator Ordnance Release units.

The need for safety and mission success has been the prime consideration in formulating system philosophy, design and implementation.

The system is basically a duplicate, “both on line” arrangement and is highly self-monitored. A release is only permitted if both lanes agree, or if, on disagreement, the faulty lane is detected by its monitoring.

The master computer and stores loaded unit accommodates the following facilities:
● Weapon loaded facilities;
● Two optically-isolated 16 bit digital processor and stores;
● Interface electronics;
● Duplicate power supplies;
● System sub-fusing.

This has represented a major design constraint and, to satisfy it, extensive use of special hybrid components was necessary with multi-layer printed circuit cards loaded on both sides with components. CMOS technology is used to minimise the resulting heat dissipation problem, and sophisticated cold wall techniques combined with channelled air cooling are used. The contract was work shared with Selenia in Rome with the majority of the design carried out by Marconi-Elliott Avionic Systems Limited with Selenia responsible for manufacturing most of the later development phase hardware.

The width of this unit tapers from 85mm at one end down to 56mm at the slanted end.

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