Hi StielGr, I found my course notes but not my photos yet. I believe the SS11 was a development of a WW2 German missile and was a little brother of another missile, the AS12. The first generation SS11 was superceded by the second generation Milan missile in UK service in the mid-late 1980s. The last users were Territorial Army squadrons of the Army Air Corps (see the handwritten info on your T10K). I remember doing initial acceptance inspections on about 300 of them in 1980 - 81. I believe they had recently arrived from the French manufacturer in Bourges. They were packed one to a box, six to a pallet in fibreglass boxes. The lid was an odd shape to accomodate the screw-on (Practice) warhead strapped in it (I believe HEAT warheads were separately packaged for UK use), with the MMA (missile main assemblage) in the lower half of the box and a small tool and missile history and record card kept in a small lidded compartment on the top of the lid. The manufacturer's film claimed `This missile is man-portable' as it showed a man carrying a boxed missile on his back as he climbed a mountain but at about 112 Lb (50 Kg?) that was stretching it. I believe one was used by Royal Marines in the ground role to score a direct hit on the conning tower of an Argentinian submarine when it surfaced off South Georgia in 1982 at the start of the Falklands conflict.
The T10K controller was otherwise known as the T10K generator. The box generated firing/launch commands and was used to control the missile in flight. It also provided a self test of its guidance signals (P & Y lamps) before firing. It had a 6 position rotary switch; a voltmeter for checking the aircraft power supply; a frequency selector switch (FF = fixed frequency, where the aircraft travels faster than 100 knots, VF = variable frequency, when the aircraft speed is 0 to 100 knots); red & green firing sequence indicator lamps (red when in progress, green when firing sequence complete); a 19 pole connector to the missile selector box and a 7 pole connector for training.
The firing and flight sequence went like this:
Minus 1 second - C position, where the air gunner has the rotary switch locked behind the ramp on the T10K - Missile locked on launcher, check Pitch & Yaw signals (the orange & white lamps).
The air gunner now lifts the rotary switch over the ramp and it continues under its clockwork mechanism.
0 seconds - O position - the latch release cartridge (the latch holds the missile in position on the launcher) fires, allowing the link rod to rise via a spring, to free the missile on the launcher and completes circuit connections.
0.15 second - IG position - Ignites the Gyro run-up charge (propellant contained within the rotor ball of the gyro), which burns for 0.15 second, to 40,000 RPM.
0.5 second - UG position - the gyro uncages (Uncage Gyro) and thermal batteries are ignited that provide the missile with in-flight power.
1 second - FB and F positions - Boost igniter and ball delay valve propellant fire (Fire Boost) and Flares are ignited. The missile launches. Note that the junction box remains on the launcher as missile/helicopter interface.
1.3 seconds - the sustain motor ignites, via the ball delay valves at front of the boost motor, 0.3 seconds into the flight.
2.2 seconds - The boost motor is burned out and the missile is fully controllable.
3.1 seconds - The fuze arms, 2.1 seconds into the flight.
21 seconds - The sustain motor is burned out, 20 seconds into the flight.
22 seconds plus - The wires are jettisoned at the junction box.
The tin-covered balsa wood wings were canted off by 0 degrees 48 minutes to give roll stability in flight. If a guidance wire broke the missile dived right.
The T10K was connected to the Missile Selector Box. The selector box was a vital part of the system, having an on/off switch, a missile selector switch, a master jettison switch (all missiles), a single jettison switch, a selection prohibition lamp (lit when a firing sequence was in progress) and a safety key as a master on/off switch. It was set up for firing missiles in the sequence Left outer (1), Right outer (2), Left inner (3) and Right inner (4).
The system also had a gyro stabilised sight - the AF110 - with three settings:
1 - Normal.
2 - x 2.5.
3 - x 10.
Flight time to maximum range of 3000 metres was about 20 seconds, not 26 as I wrote earlier (that was Swingfire). Minimum range was stated to be 400 metres (after 2.1 seconds of flight). Terminal speed was about 420 MPH. Penetration was stated to be up to two feet (60 cm) of armour plate. Flares (two per missile) were pre-fitted to operational missiles. A fuze protective cover also had to be removed before assembly of the missile. Each missile came with two thermal batteries that on assembly of the missile, were fitted to the forward end of the MMA, where they were held in position by spring clips. The warhead (HEAT 140 AC 62 B or Practice 125 59 S) was then screwed onto the MMA. There was also a Drill version. I don't know the meaning of the practice warhead info but for the HEAT, AC = Anti-Char (Anti-Tank), 140 = diameter of the cone in mm, and 62 B = year of design and suffix letter. The HEAT warhead was fitted with a Burdan anti-ricochet ring to help it grip a target at a low angle of attack. I believe it was milled, similar to the edge of eg a 10 p coin.
The boost and sustain rocket motors were of solid propellant in separate chambers, the boost behind the sustain. The `Simplet' boost motor had two side-mounted exhausts. Each had a carbon throat insert (venturi) and was closed with a melinex disc atmospheric seal. The boost motor comprised 3.6 Lb (1.6 Kg) of seven sticks of slotted tubular `Epictete E8' propellant, all burned after 1.2 seconds. Two ball delay valves were sited at the forward end of the boost motor section. Each contained propellant that was ignited at the same time as the boost motor and they burned for 0.3 of a second. After 0.3 second propellant gases from the boost motor passed through the ball delay valves to ignite the rear end of the `Sophie' sustain motor. The sustain motor was a single grain of 8.8 Lb (4 Kg) of E8 propellant with a burn time of about 19 seconds. Set into the sustain motor were three copper tubes. Their ends were exposed 1.8 seconds after sustain ignition, ie 2.1 seconds after launch (safety for the helicopter and crew in the event of premature detonation) and sustain motor gas pressure was bled off along them to arm the fuze. As Hazord has said, the sustain thrust exhausted through a central tube and missile directional control was via two pairs of jet deflectors, operated by electromagnets. All were in the eflux but when a pair was energised, one deflector would be pulled more into the eflux while its partner was correspondingly moved the same distance out of the eflux.
I will try to find my photos - they show positioning of the T10K & missile selector box etc.
