On Sep 23, 2:02 pm, (Colin Rosenstiel) wrote:
In article om,

(MIG) wrote:
The UNDMs were all from the extra build known as 1949 stock, rather
than 1938 stock as such. I think that 1949 stock consisted of only
UNDMs and trailers and allowed units to be reformed.

Not so at all. Some of the UNDMs (22 out of 92) came from the remains of
the aborted 9 car train experiment.

There were no 1949 stock cars with full driving cabs, though. They were
the first cars to be withdrawn because they were non-standard.

I've just found another source suggesting that the Northern City line
only had three-car units, and that six-car formations ran from the
opening of the Victoria Line in 1968, which fits with the report.
Presumably traffic increased with people changing and Highbury and
Islington.

It will be because of the requirement that trains had to have at least
two compressors that dictated 6 car trains all the time.


The implication, not spelled out, was that three-car units were
transferred in 1966, and ran in pairs from 1968. Maybe they had
double compressors or maybe the implication is wrong.