John Bull S-Pattern Cable Clips used on PECs
Stores Ref: ?
Used on most PECs of the cold war, these rubber cable clips were a simple design which would form an uneven figure-8, fitting around the oxygen hose and communications cable.
See the PEC reference.
It appears as though this range of cable clips was originally intended for clipping cable harnesses to motorcycle tubular frames, I wonder if this was a modification brought about by a pilot, or squipper who also rode motorcycles?
A lot of the PEC manufacturers and RAF resources I've seen (dated from the 60's and 70's) show a mix of Lassovic Tape and S-Pattern John Bull clips in use, so it's a bit of a mystery how / when these clips were introduced to PECs.
The best reference to Lassovic Tape I can find on the internet is a comment found on the pprune forum from 2009. Quote from forum user G-CPTN:
Four decades ago I 'discovered' Lassovic tape. It was tough and almost impossible to tear - stretching extensively when pulled. It also had good adhesive qualities. I used it to hold electrical instrumentation wires on a vehicle that was to be tested at -40 deg. At that temperature, the Lassovic tape became extremely brittle and snapped whenever it was touched . . .
(This was before zip-ties were available.)
Exhibit
S-Pattern John Bull Cable Clip
S-Pattern Cable Clip taken from an aircrew PEC and flattened out, this image was captured in my flatbed scanner. This clip is still supple and strong.
Mk1 PEC dated September 1972
Three S-Pattern clips can be seen fitted to this PEC, keeping the communications cable close to the oxygen hose. These clips could have been installed at some point, as an upgrade from Lassovic Tape, or may have been part of the original build, this is unclear.
Manufacturers Resources
John Bull catalogue extract, page 40, 1954
Found at: TheVincent.com, the S-Pattern is the clip at the top of the image.
Overview of personal equipment connectors, Airmed, WW191 Issue 4, July 1975
This 1975 document shows the S-Pattern clip installed on a Mk8 PEC.
Whereas the same 1975 document also shows the Mk1 PEC (below) fitted with Lassovic Tape instead, so it's very unclear as to how / when these were introduced to RAF / RN PECs.
