line speeds

[whole diary]

[The SprinterMeister]

I was driving along the a30 lastnight when I noticed a train Exeter bound and was struggling to keep up at legal speeds? Was between Exeter and honiton

yeh but seriously anyone know

The overall line speed limit on the Southern below Salisbury is 85mph. 60mph through Honiton if routed by the main line, 25mph through the up loop line. Think there might be a differential speed limit at Gittisham heading towards Honiton which is to do with the braking distance from the Honiton up distant to the signal controlling access to the up loop. Don't know for sure as I haven't signed the Mule for years.

[The SprinterMeister]

the 159's started life as ordinary 158's with bsi couplings but were converted to 159's by a company in scotland,they did have 4 step braking in the early days i think as part of a trial initially and it was later put to standard 3 step.
i believe there was nothing to stop them being ran in multiple despite the 4 step although network south east preffered them not to be used with other 3 step braked units,not sure why this was the case though.
the only major difference between 159's and similar 3 car 158's like the ex-tpe stuff is the toilet retention tanks and SWT^▸ (South West Trains) have got modified driver switch and door control panels fitted now.
these days 159's can be coupled to other dmu's with compatible bsi couplings for example the 2 and 3 car 158's aquired from TPE^▸ (Trans Pennine Express).

The 159's did NOT have 4 step braking from new. Urban Mythology I'm afraid. They were built with standard 3 step braking which they still retain. Only difference as far as the brake controls are concerned is there is an emergency stop plunger on the secondmans side which is used during driver training and so forth. They were built as three car 158's, they would have been 158873-895 in the scheme of things, they have the same 400bhp Cummins as the 158863-872 batch of cl158. The interiors were delivered part fitted out, Rosyth Dockyard doing the conversion to 159 interior layout and fitting the first class section, toilet tanks etc.

The delay in fitting toilet tanks to the 159/1's was due to the engineering drawings for the original tanks being mislaid when Rosyth changed hands, a spare tank at Salisbury was cut up and measurements taken in order to obtain the tanks for the 159/1's.

There were thoughts about re-engineing the 159/1's to take the 400bhp Cummins although it doesn't in fact show any performance advantage over the 350bhp Cummins used on the FGW^▸ (First Great Western) ones. The step up gears within the transmission have a different ratio which has the effect of keeping the 400 Cummins below its rated BHP. As there is more involved than swapping the engines (The transmission, rads and oil cooler have to be changed as well) I doubt this will happen.

[6 OF 2 redundant adjunct of unimatrix 01]

I was driving along the a30 lastnight when I noticed a train Exeter bound and was struggling to keep up at legal speeds? Was between Exeter and honiton

yeh but seriously anyone know

The overall line speed limit on the Southern below Salisbury is 85mph. 60mph through Honiton if routed by the main line, 25mph through the up loop line. Think there might be a differential speed limit at Gittisham heading towards Honiton which is to do with the braking distance from the Honiton up distant to the signal controlling access to the up loop. Don't know for sure as I haven't signed the Mule for years.

thankyou, so basically i wasnt the only one slightly over the speed lim?.. a descrepancy which i resolved asap of corse

[G.Uard]

I won't take up space in quoting all of TSM^▸ (Track Section Manager)'s reply ref 4 step braking from above, but I am pleased to see this issue laid to rest.  Urban myth it may be, but a very widely believed one.  Even that constant source of information Wikipedia, seems to think that 4 step braking was fitted on conversion from 158-159/0.  Thanks to TSM and smithy.

[smithy]

TSM^▸ (Track Section Manager) may well be correct but i have it on good authority that in early days 159's did trial a 1 bar pressure increase in emergency much like turbostars in essence giving it a 4th step,the trial was later removed and they were reverted back to standard 3 step.

[The SprinterMeister]

TSM^▸ (Track Section Manager) may well be correct but i have it on good authority that in early days 159's did trial a 1 bar pressure increase in emergency much like turbostars in essence giving it a 4th step,the trial was later removed and they were reverted back to standard 3 step.

They never had enhanced brake pressure in emergency either. It should be remembered that Exeter men signed them when they were new. The work all went to Salisbury / Waterloo when the shadow SWT^▸ (South West Trains) franchise was created.

It might be they have enhanced emergency braking now, I will ask a SWT Sarum driver when I see one to ask.

[onthecushions]

Diverting a little, I've noticed on HST^▸ (High Speed Train) journeys into Paddington, on occasion the train paces aircraft coming into land at Heathrow. Sometimes the train even gains on the planes. Headwinds perhaps?

OTC

[G.Uard]

According to Air New Zealand, the landing speed for a Boeing 747-400,
one of the newer long-range versions, the landing speed is 200 km/h or
124 mph.  This is the landing configuration with full flaps and slats
deployed, which slow the aircraft significantly over its "clean"
landing speed.  So possibly. 

Air New Zealand
"Aircraft Statistics"
http://www.airnz.co.nz/aboutus/resourcecentre/aircraft_statistics.htm

The Boeing 767-300 and 767-200 both land at 240 Km/h or 149 mph:  Only a 143 could keep up with one of those.