I always aim to make mine a challenge, or at least interesting!
I will be taking the floor if it is still available tomorrow evening. Until then, someone else can have it...
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A fairly rare sight as a general rule, this unit is or was however very common in the areas it serves or served.
Not especially numerous at only 43, but a very common sight in Birmingham and Manchester.
Its capacity is or was very high for the number of coaches it has or had - almost too high.
284 seats in a 3-car train is substantial and if anything verging on uncomfortable; compare the same 284 on c2c 357s.
One unusual feature about the train makes or made it quite popular among enthusiasts, but not all.
The engine noise when accelerating and especially decelerating makes it sound vaguely like a sports car, possibly even an F1 car. Many enthusiasts are appreciative of this unusual feature.
Several similar classes exist(ed) in what is now Southeastern territory.
465s and 466s are virtually identical by build and are a common sight under Southeastern.
If listed by TOPS number, the class after this is or was very rare.
There is no 324 so the next class is 325 - one of the rarest classes out there.
There is a clue out there, relating to the enthusiast clue, that would give it away.
I hate the damn things! This relates to the clue about enthusiasts' perspective, above.
But the class is or was not exactly... abundant, unless of course you live(d) in one of several certain metropolitan areas.
As shown above, the 323 is quite rare, unless you live in Birmingham or Manchester.
unlike the 503, the unit in question is actually similar in design to the rarer class that follows it.
The 325 shares many characteristics with the 323, although the front end is different.
One thing I will say is that the numbers aren't necessarily consecutive, but there is no intermediate between the two. There is no 374, for instance, so from the Eurostar we will find the SE 375. (Before anyone asks, 373 is also wrong.)
As shown above, the 325, the next class by TOPS, is very rare.
I'll make it a bit easier. This class is still in service today and does not serve London.
323s still run and rarely go any closer to London than Birmingham International (or possibly Coventry).
As far as TOPS goes, the 321 was a pretty good guess.
Only the 322 separates the two!
The next clue would have been thus: This class was the last built by its manufacturer.
Hunslet closed after the completion of the 323 order.