Work Day 25th January 2020


No work this week


We have six I/O rack fan trays. See the accompanying photo which shows a ‘stack’ of all our fan trays consisting of the three installed trays belonging to our LCP 1022, two from LCP 1006, and a donated tray.

I-O Rack Fan Trays.jpg

Note that one tray has a different ON/OFF switch as supplied by Ferranti, probably an earlier variant as it has the earliest serial number. Five of the fan trays will now have their fans removed and refurbished to give them another lease of life, after all they are 35 years old.


Priming of prepared paintwork took place on the internal walls of the LCP cabin. See accompanying photo which shows the original paint, primed exposed metal and a sample patch of the new cockpit green paint.

LCP Internal Repaint.jpg

From 3rd Line

Bolts and Pin Paint Stripped

The attach photo is showing three of the ‘hollow’ bolts that mount the desiccators on the waveguides and an anchor pin from the pedestal roof. They were clogged with many coats of paint but two days soaking in paint stripper sorted them out.

Bolts and Pin Paint Stripped.jpg

Pete H

Work Day 18th January 2020


Work continued on preparing the pedestal and aerial system for a repaint. The Radiation Absorbent Material (RAM) on the top section of the pedestal has been refurbished by filling cracks and then rubbing down. The aerials are currently on their back so preparation work was carried out on the waveguides, aerial boom and the area around the top junction box and inside face of the elevation gearbox. See accompanying photos.

T86 Ae System Refurb.jpg

T86 Pedestal Refurb.jpg

The refurbishing of the top junction cover box has been completed, apart from fitting new rubber tubing from the vents to the desiccator. See attached photos.

T86 Top Dist Panel Refurb 2.jpg

T86 Top Dist Panel Refurb 3.jpg


The positive and negative 6V DC power supplies in the display console are stable again following disconnection of the Dish/Launcher box. This unit is not used in the simulator mode so finding the fault that is affecting the power supplies can be left until the team has more time.

Work has started on preparing the internal walls of the LCP for a repaint. The accompanying photo shows the general condition of the walls, paint has come away at the roof join and is in generally poor condition.

LCP Int Wall Rub Down 1.jpg


Away from Cosford at 3rd Line

1. SCSI Disk Emulator

The Argus 700 in the LCP now runs using a solid state SCSI disk emulator and a new version of the emulator is available which has been purchased and tested. The accompanying photo shows the test set up which includes the SCSI disk emulator under test, tape drive and tape controller.

Testing SCSI2SD.jpg

The assembly is connected to an Argus 700 and can boot the Bloodhound software. Testing was successful and the new SCSI disk emulator ran without a problem.

2. Fan Trays

I have finished refurbishing an I/O rack fan tray. We now have several spares of these trays so my plan this coming Saturday is to check the three in-situ I/O fan trays and the spare(s) in the LCP and check their fans. If any have fans that are dead or running slow I’ll swap out the fan trays to ensure all are ‘A’ OK.

The three fans in this refurbished tray were all refurbished a few weeks back but the tray itself needed some TLC. It was dirty, had patches of corrosion and the odd dead spider hidden in the cabling The fuse holder was broken and had to be replaced (good old eBay). The attached photos show the ‘kit of parts’ as dismantled and the other two photos the fan tray reassembled. The green dots on the fans cover the screws that dismantle the fan.

I sorted the A700 tray a few weeks back with refurbished fans. We have a spare A700 fan tray which I use on the test rig but it has 2 U/S fans.

Fan Tray Kit of Parts.jpg      Fan Tray Reassembled 1.jpg


Fan Tray Reassembled 3.jpg

A reminder … the computer racks use two types of fan:
EBMPapst 4650N – Argus 700 (six fans)
EBMPapst 4850N – I/O Rack (twelve fans)

The original fans were a mix of those that can be refurbished and those that can’t. Those that can are held together with two small screws, those that can’t are held together with two large hollow metal rivets (on the early models) which can’t be replaced by me at least. If the coil is O/C then the fan’s dead which was the case on a recent fan failure on the Argus tray.

The cost of new fans is another factor for new fans and we have looked at alternatives. Three X-Fans have been used in a spare unit for the base of the I/O rack but the nearest direct comparison to the Papst fans are supplied by SUNON. The SUNON has the same connector on the fan as do the Papst fans but … the air flow is in the opposite direction so can’t be mixed on a tray. The only requirement for new fans at the moment is for the spare Argus 700 tray and there’s no panic to get new fans at the moment. For info, Argus tray fans are:

Papst fans are £30 ish (they were a lot more but have come down in price)
SUNON fans are £18 ish

Cost makes a difference when six are needed to convert an Argus tray. Currently I buy individual fans as needed but they have to be Papst fans unless we replace all the fans on a tray (Argus six, I/O three).  … please note that all contributions are gratefully received as this project is totally funded from personal resources.

Pete H

Work Day 4th January 2020

Back to work at Cosford after the Christmas/New Year break. There’s no heating in the hangar so painting on-site is on hold (apart from the internal cabin walls) until the weather improves but there are still plenty of other tasks to carry out.


The In Flight Reference (IFR) aerial’s waveguide assembly was refitted and apart from some paint touch up work it is now ready for refitting. A task that will wait until the rest of the aerial assembly has been repainted. The accompanying photo shows the refurbished IFR aerial.

IFR Aerial Re-assembly wm.jpg

I’m currently refurbishing the modulator box from the aerial assembly at home and managed to remove three of the four bellows to ‘do a good job’!

Bellows from Mod Box wm.jpg


Before running the simulator I inserted the repaired MP140 into the Argus 700. It needed a new crystal, due to corroded leads, and tested operation of the keyboards and tracker ball; all proved to be OK. On the spare MP140, which was removed to enable the test, its crystal is showing corrosion around the edge and has been taken back home for repair at before it goes U/S.

The intention was to remove all the cards from the Argus 700 due to the damp conditions in the hangar over the winter months. During a final check of the simulator it was noted that two power supplies in the console had constantly varying outputs. Changing these power supplies with spares will be a first task for the next visit to Cosford. The varying voltages did not affect the running of the simulator which is a bit of a puzzle.

Pete H

%d bloggers like this: