wondering about this 125mph bi-mode Flirt. A 9-car version would need at least 3 diesel power modules (4 engines each), taking up valuable platform space. Interesting to see what Stadler have in mind.
-
Our new ticketing site is now live! Using either this or the original site (both powered by TrainSplit) helps support the running of the forum with every ticket purchase! Find out more and ask any questions/give us feedback in this thread!
Abellio Greater Anglia Class 755s (Regional Trains)
- Thread starter swt class 450
- Start date
Sponsor Post - registered members do not see these adverts; click here to register, or click here to log in
R
RailUK Forums
Bletchleyite
Veteran Member
XC trains are not by and large operating at maximum lengths so this is no more of an issue than an HST.
I was thinking more of other regional routes, yes I guess they may come with something for XC but equally they be likely up against an Hitachi 802 variant, and the Bombardier Bi-mode plus others perhaps.
43096
On Moderation
- Joined
- 23 Nov 2015
- Messages
- 16,773
Probably easiest to put the engines at each end of the train. Could even give the vehicles a name that reflects what they do. Something like “power car” perhaps? Stadler already have the basis for such a vehicle - it’s already in service as Class 68/88.
Why would it need three power units for only 9 cars? Maybe Stadler can make more a more powerful power unit.
edwin_m
Veteran Member
A nine-car with two power cars (8 engines total) would have a better power:weight ratio than a three-car (2 engines) but worse than a 4-car (4 engines), so shouldn't have any problem getting to 100mph, but as a rule of thumb 125mph takes twice as much power and the extra power in a Meridian/Voyager helps with acceleration at lower speeds too. So the FLIRT on diesel power might not be able to match those timings.
Remember the Bi-Modes have a max range of 500 miles before refueling.
on diesel, yes. Might seem obvious but are bigger fuel tanks an option? Stadler will know what can be made to fit into their bodyshell.
that's why I suggest the 4-engined pod in a 3-car, times 3, in a 9-car formation. That ought to comfortably have enough power for 125mph travel.
I would expect that they have maximised the fuel tanks for the space available, so no. That said, if you are willing to forgo the corridor that runs through them (and put them at either end of the train, rather than the middle), you may well be able to get a larger fuel capacity
43096
On Moderation
- Joined
- 23 Nov 2015
- Messages
- 16,773
As I said above, rather than putting two or three power modules through the train, once you get to six or seven coaches and above, it's far better to put the engines in a power car at the end of the train. That also allows bigger fuel tanks.
diesel power car at each end is moving away from Stadler's distributed power concept.
A power module with only 2 engines would have the same size fuel tank therefore double the range, you could have more power modules? Nah.
What we need is a 125mph bi-mode loco. Class 88 with the big engine, which of course does not fit the UK loading gauge.
Interesting puzzle for Stadler to solve.
That depends if you are interpreting power car in the traditional HST sense, or in the sense of a vehicle with power generating equipment in it! The powerpacks for the bi-modes that this thread is nominally about are on unmotored bogies, indeed only the outermost bogies are motored according to this post - so the type of thing that @43096 is proposing would just be these bi-modes in reverse!
or something like the old 210
43096
On Moderation
- Joined
- 23 Nov 2015
- Messages
- 16,773
Not necessarily. Diesel power car at each end, with cabless FLIRT type vehicles in between with traction equipment, including pantograph, transformer etc. Under 25kV AC you stick the pan up and shut the diesels down; opposite if you need diesel power. Basically, what IEP should have been....
Stadler are very good at coming up with bespoke solutions: it's what they made their name on and they still do such trains today - for example, the Swiss metre-gauge railways by-and-large get all their new kit from Stadler.
indeed they are. The power module's diesel engines are 520kw/700BHP, 4 of those and we are at 2800BHP, a considerable increase over an HST power car. A pair of those top and tail a 9 car with Stadler's favoured articulated bogies would give a lightweight rake that would go like the proverbial. Much to like. Will they see the light of day here?
Pete_uk
Established Member
Could someone inform me of which Axels are powered on these bi modes?
Just the outermost bogies - see post 39 which details axle laypit, power, etc
normally the outermost of a set is powered but in Stadler's blurb there's the strong suggestion that an intermediate bogie could be powered in addition if the performance spec calls for it. At 1300BHP per bogie one could achieve 5200BHP installed in a 3 car set, which would do wonders for its 0-60 time and top speed.
James James
Member
- Joined
- 29 Jan 2018
- Messages
- 426
I think only the conventional bogies can be powered, but not Jacobs bogies: the 7 and 8 car Flirts (belarus, or PKP and soon SOB) all have an additional 2 conventional bogies in the middle of the train (i.e. 2 conventional bogies instead of one jacobs bogie joining cars), which does suggest that those are being used for additonal power. On shorter trains, I don't think the Flirts even use all axles for driving, e.g. 3 axles might be driven on a 3 car train with a total of 8 axles. And SBB's 4-car Flirt's accelerate ridiculously fast with 2 powered bogies (not sure if 3 or 4 axles driven), those units are probably the most powerful Flirt's in existence. (I believe there were some injuries when the SBB Flirt's first went into service because they accelerated faster than standing passengers expected.)
Interestingly, the GA Intercity EMU has two conventional bogies per 2-cars (i.e. 2 cars use 1 conventional bogie + 1 Jacobs + 1 conventional). I doubt they're powering all of those, perhaps its to simplify maintenance/allow for easy removal of sections of the train.
Now, in the standard European EMU Flirt's, transformers are all located behind the cab, meaning the end bogies carry the largest weight and thus have better traction - those center bogies would therefore also be less useful.
(The 250km/h capable Giruno is all Jacobs bogies though, so presumably Stadler can motorise Jacobs bogies - they just seem to have avoided it on the Flirt so far. Even then, only 4 bogies are motorised for an 11-car train, equivalent length to a conventional 7-car.)
Last edited:
Some pics in this blog* post:
http://busandtrain.blogspot.co.uk/2018/05/guest-post-new-stadler-trains-for.html
(*not my blog)
http://busandtrain.blogspot.co.uk/2018/05/guest-post-new-stadler-trains-for.html
(*not my blog)
dk1
Veteran Member
Totally disagree. It's made it IMO. We all see things in a different way.
Class 170101
Established Member
- Joined
- 1 Mar 2014
- Messages
- 8,389
The Stadler won't be suitable for XC or Northern unless the fuel tank can be pushed significantly further than currently designed.
Wivenswold
Established Member
I was looking forward to seeing the units in their original planned livery but I have to admit the yellow actually makes the train look more dynamic.
dp21
Member
- Joined
- 10 May 2017
- Messages
- 358
Just to clarify, on the BMUs only the outermost bogies are powered, on the IC/AIR12s the outermost AND centremost bogies are powered.
61653 HTAFC
Veteran Member
Perhaps the headlights don't quite meet the standard required for the yellow to be omitted?
They do meet the standard, but as discussed earlier in the thread, there were issues with the risk assessments for some level crossings on the rural network which prevented them taking away the yellow front.
It isn't just as simple as "Are the lights LOC & PAS TSI compliant - paint it whatever colour you like" - If there is a significant change (such as moving to a non-yellow front end) this counts as a "significant change" and so must be subject to "Common Safety method on Risk Evaluation & Assessment" (CSM RA). When doing this risk assessment, you have to consider operating conditions, the safety of railway workers, passengers, and the public, safety at level crossings, and other factors. If for whatever reason the risk assessment chucks out a result that is of concern (ie high/high risks) and you can't mitigate it effectively, you can't then go forward with that significant change.
Whether or not the fact that the train has got a patch of yellow on the front makes it less likely that there will be a level crossing incident is a whole other debate, but it is what it is.