2 bendies vs 3 DDs can
alight assuming the same space, and this brings us to the following
example I have posted before:
Based
on the absolute space taken, the DDs win, but a stationary bus is a
sitting duck. When you take into account of the flow, you will
realise more pax can be cleared with a bendy.
Based
on observations, bendies take less than half the time of DDs
dwelling at busy bus stops, having similar and significant boarding
and alighting activities. Using simple, easy to calculate numbers,
the calculation is as follows:
In a
given 6 minutes time frame, and 36 m space. As you have said 3 DDs
OR 2 bendies can fit into the space. But lets simply assume a bendy
takes half the time (in fact, in reality, more often than not it
takes less than half) of a DD. And for simplicity sake, lets assume
a double deck takes 3 mins (at stops like NP and SIM, 5 mins is not
unheard of), and a bendy takes 1.5 mins. Ie each DD space can be
used by 2 DDs in 6 mins and each bendy space can be used by 4
bendies in 6 mins.
You
could fit 3 DDs x 2 buses per space OR 2 bendies x 4 buses per
space.
So in
a given 6 minutes time frame, you could fit 6 DDs OR 8 bendies.
The
above calculation was deliberately made simple, but it can be
extrapolated to fit different dwelling times.
The above assumes a DD
takes just 3 mins while a bendy takes 2 mins. In reality, DDs can
take 5 mins or more to complete boarding and alighting (see 74, 154
at NP/SIM or Clementi MRT). And also note that typically, a bendy
can take in a few more people than a DD in terms of total
capacity.
How about DDs where people don't move upstairs? Like DDs on 222,
291, 983 where it takes some effort for the drivers to get them
upstairs, or in the case of 291, the DD is delayed such that the
next bus (usually a Scania) is at waiting behind to enter the
berth. Do you know that before the introduction of 983, there
wasn't a need to place any staff at CCK Ave 5 (the former 300
u-turn part) to force people to move to the rear of the 300 bendy
but a few days after 983's DDs were introduced, during the morning
peak, staff have to be deployed to force people to go upstairs?
Waste of resources as the staff could be used for other things like
controlling buses at the interchange.
How sure are you that passengers can't hear a bus driver
shouting on a bendy when usually you will be able to hear the
commotion even when sitting at the last row of a bendy, maybe you
don't sit there often so you won't know.
last time already ask u how many bus stops will have such
significant boarding/alighting activities but u cant answer.
you have mention SIM/NP/Clementi Mrt bus stops.. what about
other bus stops whereby the whole bus load of paxes will alight and
another whole bus load will board? cant find much also, except for
some MRT station bus stops (but mostly it is either alighting or
boarding, seldom will have whole bus load alighting then another
bus load board)
For clementi mrt bus stops, not all bus services have
significant boarding /alighting activities also, (maybe 154 some
trips/some timing, 184 some trips/some timing)... pls do not tell
me that every single trips of 184 bendy will have 100 paxes
alighing at the bus stop...
for NP/Sim, if during am peak, mostly will be alighting only.
while for afternoon trips, mostly will be boarding (alighting still
have, but not the entire bus load).. so basically, the dwelling
time should be the same for alighting during AM (or lesser for
DDs).. (assuming u have 3 DDs unloading 300 ppl together
compare with 2 bendies unloading 200), or if compare boarding
activities during PM, 3 DDs will have less dwell time for boarding
compare to 2 Bendies...
we still haven compare those bus stops for which 2 DDs can do
boarding/alighting, but only one bendy can do boarding/alighting..
(esp for boarding situation only). 2 DDs can board together (assume
no alighting) and carry 200 paxes in 3 mins? while one bendy can
only carry 100paxes in 3 mins (since only one door for
boarding)..
in your example above, you have assume that DDs have double
alighting time as compare to Bendies... but in reality, is it
really double the time whereby paxes can also alight using front
entrance (so 2 exit for DD compare to 3 exit for bendies).
Bendies have its own usefulness, but in Singapore, space is an
issue..
to park 300 bendies in a depot, need 50% more space than to park
300 DDs...same go for interchange...
LTA should throw some DDs on those intratown/SMRT feeders to see
whether paxes will go upper deck or not since SMRT is now using
their MAN A24 on long haul route instead of
feeder/intratown...