Prestige15
On Moderation
Just a curious question, Is it possible that modern DMU's such as 170-196 can run at 110mph?
as do VoyagersClass 180s run at 125mph
That pretty much sums it up.Engines & transmissions might permit these units to physically reach that speed but there's a lot of considerations, testing and modifications would need taking into account before they would be permitted to.
Suspension considerations (normal and degraded), braking, effects of continuous operation on the drivetrain & auxiliary systems at the higher speed; warning horn and frontal lighting effectiveness, cab ambient noise levels, structural impact resistance including couplers, effects of high winds on stability/rollover resistance, effects of passing infrastructure or other trains at higher speeds, AWS modifications for >100mph running, likely wiper modifications, the list would go on and on.
Years ago if some may remember when the class 175 were announced, they were ment to be 125mph, Basically a shorter 180, Cant imaging a 2 car doing 125mph.
According to North West Coast Railway (source here): "When North West Regional Railways was franchised to the Great Western group in 1997, the package included the introduction of 70 new diesel vehicles to displace the 40-year-old 'heritage' stock still in service and to pioneer a service to London in competition with with Virgin, both from the Manchester area and the North Wales coast. Initially it was suggested that some would be 3-car sets capable of 125 mph for the London services, whilst the rest would be a mixture of one-car and two-car sets. GEC Alsthom were soon chosen as the constructor, and the initial thought of single cars was revised to 2- and 3-car 100 mph sets plus 9 three-car 125 mph sets. Artists' impressions from 1997 show the more streamlined front proposed for the faster units." So essentially some of the 175s were intended to be 125mph capable for London services. I tried to do some digging for the original artists impression but to no avail.Were they? Not only do they not have a less powerful engine than the 180s, but they are also slab fronted and have passenger accommodation right next to the cab, which no other 125mph stock has - the 175s simply are not a 125mph design whichever way you look at it.
As for if other contemporaneous DMUs could do 110mph, it would theoretically be possible I'm sure, but would almost certainly involve re-gearing at best, or complete drive line replacement in the worst case (looking specifically at the 170s!). The train body/suspension etc should be able to do 110 without too much difficulty
It was pointed out by wikipedia and RAIL 20 odd years agoWere they? Not only do they not have a less powerful engine than the 180s, but they are also slab fronted and have passenger accommodation right next to the cab, which no other 125mph stock has - the 175s simply are not a 125mph design whichever way you look at it.
As for if other contemporaneous DMUs could do 110mph, it would theoretically be possible I'm sure, but would almost certainly involve re-gearing at best, or complete drive line replacement in the worst case (looking specifically at the 170s!). The train body/suspension etc should be able to do 110 without too much difficulty
It was pointed out by wikipedia and RAIL 20 odd years ago
Chiltern's 168s originally came with an option to be modified to work at 110mph but it was never taken up I believe.Just a curious question, Is it possible that modern DMU's such as 170-196 can run at 110mph?
Neither of which are exactly known for being reliable sources!
Or in other words, some of them might be able to reach 100 mph, but they would possibly be knackered if they ran too fast for too long??Engines & transmissions might permit these units to physically reach that speed but there's a lot of considerations, testing and modifications would need taking into account before they would be permitted to.
Suspension considerations (normal and degraded), braking, effects of continuous operation on the drivetrain & auxiliary systems at the higher speed; warning horn and frontal lighting effectiveness, cab ambient noise levels, structural impact resistance including couplers, effects of high winds on stability/rollover resistance, effects of passing infrastructure or other trains at higher speeds, AWS modifications for >100mph running, likely wiper modifications, the list would go on and on.
I doubt a 170 could get to 110mph, unless perhaps down a fairly steep gradient.
Oh I dont know about that. Darn limiter always cut in at 102mph and speed wouldve kept climbing otherwise.I doubt a 170 could get to 110mph, unless perhaps down a fairly steep gradient.
I doubt a 170 could get to 110mph, unless perhaps down a fairly steep gradient.
for those saying that units without aerodynamic fronts clearly can't do high speeds, or two car units, etc- I appreciate they were an EMU, and that changes things, but the Metroliner in the USA was a two-car unit specified to be capable of 160+mph, could actually do 150mph fairly well and had slab ends (with corridor connectors behind doors). You can go fast if you put in power, gearing etc. All of which is possible with a mechanical/ hydromek DMU, but whether it is desirable is a whole different issue