Recording the History - Recalling the Memories.
CABLE LOOM FROM MISSILE.
90 Wires carrying Missile and Fuze parameters for selection to send back to ground during flight.
Rack 1 Rack 2
The CMI Room
(Control & Monitor Instrumentation)
RAF BLOODHOUND
INSTRUMENTATION LAUNCHER CONTROL ROOM
Building 255
TWO RACKS
One for Each Launcher
TWO RED
STOP BUTTONS
to Stop Launch in an Emergency
and if WREBUS Meters shows a fault.
Active down to zero seconds.
Runs the PIP on mains supply on the launcher, until a few minutes before launch, when the batteries are switched in.
INSIDE THE BLUE BOX BELOW-THE PIP AS MOUNTED IN THE WARHEAD BAY-IN PLACE OF A WARHEAD
SAFETY & ARMING MONITORING UNIT
PRESSURE TRANSDUCER ASSEMBLY
SAFETY & ARMING TRANSDUCER.
An Accelerometer holds off the Break-Up Signal until after the Boost Motors Fall Away.
(So the Missile does not Explode during the first 4 seconds or near to the ground)
EVERYTHING in the WREBUS Break-Up System is DUPLICATED.
EXCEPT the WREBUS BATTERY and the EXPLOSIVE CHARGE.
Everything gets tested right up to the battery. The explosive cannot be “tested” as such.
MISSILE BREAK-UP UNIT
(Small Module Mounted outside the PIP, through the Warhead Bay Panel)
EXPLOSIVE CHARGE
Small enough to blow a hole in the side of the missile and make it unstable
This unit Indicates the state of the WREBUS on the launcher, and airborne up to detonation. (Or Not!)
All Duplicated
The Weapons Research Establishment Break-Up Designed Receiver.
Everything is Duplicated
Made by Rank-Bush-Murphy at Welwyn Garden City
These Duplicated Break-Up Signals are HELD OFF until a KILL signal is received from the ground, or there is complete loss of that signal. IF the WREBUS should fail to work, the Timers in the Break-Up unit do the job. Should these ALL fail, the Target Illuminating Radar is immediately switched OFF making the missile tumble. Don’t ask that question you are thinking “What happens if.”
SPIKE ANTENNA
Starboard Side
48 Way Multiplexer
A high speed motorised switch send 47 types of information back to earth.
24 Way Multiplexer
A second high speed motor selects an extra channel from every other revolution of the P3
THE ANTENNAE AT THE TAIL END
SLOT ANTENNA
Starboard Side
COIL ANTENNA
Starboard Side
WREBUS MISSILE REAR FIN ANTENNA
Port Side
Incoming WREBUS Held-Off Break-Up Signal
Just like the Railway Train Whistle theory, this signal when re-transmitted tells Range Control the Velocity of the missile at all times.
A signal received from the FPS16 Tracking Radar is amplified and re-transmitted to be received by a second FPS16, ensuring Range Control never lose track of the Missile in the bay.
LINKS AND SPECIAL FILTERS.
A choice is made here by RAF Personnel during Telemetry Installation, of just what 72 channels of data will be selected for sending back to Telemetry Receivers on the Range, for Trials Analysis to pour over for weeks to come.
Some of these channels are
Not Negotiable , Like WREBUS Receiver,
All Voltages,
Wing and Dish Angles
WREBUS Relays
Explosive Battery
Etc, etc etc.
Image of a stripped down Accelerometer will be shown here on-line one day. (When I can find it!)
Six very expensive High Current Silver Oxide Batteries filled on site with an Alkalin solution, Guaranteed to last the length of the flight, plus a period for testing on the launcher for 28 days
The PIP , or Pressurised Instrumentation Package used in the Bloodhound Mk 2 is made of heavy cast thick steel painted white. It has removable Top and Side Panels to gain access to all internal areas. The PIP weight when completed, is the same as a missile Warhead, which it is designed to replace in the Warhead Bay. A removable Battery Box with lid, holding six Silver Oxide Batteries, is fitted in the top of the PIP in place of a cast steel panel. The batteries come fully charged but have to be filled with Alkaline prior to fitting in the Battery Box. These batteries cost in the region of £150 each (in 1966) and are scrapped after just 28 days to comply with the Swiss manufacturers conditions of use. If a missile on the launcher is not fired within those 28 days, the Missile is returned to MSF for the warhead bay to be removed and new batteries to be fitted. A frequent occurrence in bad weather or because of “bad trawler-men”.
Battery recharging WAS possible, but not allowed for a firing, as the manufacturer would not guarantee the result. The Swiss manufacturer seemed to know how to make quick a “bob or two”, as we scrapped an enormous amount of batteries over the years,
Please Note:
This very basic diagram was produced from a page I found amongst my old notes.
This diagram, then on a large board, alongside an open PIP on it’s test cradle, formed part of a telemetry demonstration to visiting VIP’s, Air Commodore’s and other dignitaries etc, visiting Building 247 in the 1960’s and 70’s.
It was usually accompanied by a demonstration of a Missile on the MOTE undergoing pre-firing testing with the dish and wings moving in unison. Bear in mind that the Bloodhound Missile was still very SECRET in those days. So secret in fact that if any photograph’s were likely, the Fuze Aerial’s along the warhead bay had to be disguised with black Duct Tape.
The PIP Block Diagram below is fairly self explanatory to any missile type Techie, so as it is unlikely that many other visitors will be that interested in it, and it has taken me several hours to produce the diagram as it is, I have not expanded on the complete explanation of the inner workings of the PIP Telemetry Equipment.
If you have any questions, you can Email me. I will answer any that my old memory will allow Mike
The Pressurised Instrumentation Package (PIP) Block Diagram
YOU MAY NEED TO USE CTRL + & CTRL - TO MAKE THIS PAGE FIT YOUR SCREEN
This space reserved for an image of the PIP if I ever come across one.
