Roland Perry wrote:
In message
-sept
ember.org, at 22:18:44 on Wed, 27 Apr 2016, Recliner
remarked:
Mr. William Rodgers - My Department contributed 25 per cent. of the
total expenditure of £18.5 million incurred up to 31st March 1975.
Expenditure since then, estimated at £7.2 million to 31st December
1976, qualifies under the Local Government Act 1974 for transport
supplementary grant at the rate of 70 per cent. The total cost of the
work outstanding at 31st December 1976 is estimated to be £3.6 million.

http://hansard.millbanksystems.com/w...761215_CWA_194

So the total cost was approx 18.5 + 7.2 + 3.6 = 29.3 million.

Using RPI, that would be around £220 million in todays money.

Of course that was for the original two-station extension, but it
nevertheless seems very low (and presumably doesn't include anything for
the several additional trains needed for the extension, but presumably
ordered in anticipation).

Tube lines have fleets of identical trains, you can't just order a few
more later.

Do you really think that?

I must be imagining the extra train ordered for the Met to cover the
Watford Junction extension, the extra carriages and trains ordered for the
Jubilee line (even after the original UK factory that assembled them had
closed), the extra carriages and trains ordered for the Overground, the
extra carriages and Pendolino trains ordered for Virgin (also after the UK
assembly plant had closed), the pending order for new Northern line trains
for the Battersea extension, etc.

But in this case, the 73TS were built while the Heathrow extension was
under construction, and a large enough fleet to cover it was ordered.
Without that extension, the order would have been for a significantly
smaller fleet. They were later modified to have more luggage space by the
doors, with fewer seats.


What was the total cost including the two separate, subsequent extensions
for T4 and T5, the latter also requiring a new grade-separated underground
junction for the T4 and T5 lines to the west of the T123 station? Those
extensions would certainly have much more than doubled the total cost.

And generate double the fares.

Probably not double (have you seen how few people use the T4 station?), but
more certainly. But if you're going to estimate that total incremental
revenue (as you did), then you also have to look at the total investment.