North Yorkshire Moors Railway General Discussion

I had to chuckle at the "team shed" posts after they "fixed" the visiting class 37.

Which clown hired in a loco without working vacuum brakes for a preserved line that only has vac braked stock? Surely this would have shown up in their pre visit inspections?

 

Oh yes? Pray, do tell us how. I'm sure the regulators would love to know of this happening.

Peter

 

Yes but is that a viable option for daily operations though?

 

I thought I read on another forum it was staying.

 

That is not what you said though. You referred to an air only loco on a vac only train - no mention of any dual braked vehicles, either loco or coaches being involved. @Simon Smith was referring to a loco that was hired in for the summer to assist with the Whitby service and not just the gala. His post asked a valid if impolite question.

Peter

 

It is. I believe the NYMR's SMS doesn't allow vacuum braked locos to translate for air only locos, though I'm sure @Steve or @torgormaig will confirm.

In fairness, I wouldn't blame the NYMR at any point for the non-availability of 37688 at the start of the gala. The loco has hardly been used recently and there's no vacuum braked stock at Crewe to test the system on properly. Creating enough vacuum on the loco alone is a lot different to trying to suck the air out of half a dozen coaches.

 

Not really my field, but I thought you could test the vacuum ejector on a loco in the absence of any vac-braked stock by adding a blank over the end of the vacuum pipe that had a small (ca. 1/4 inch) hole in it? With the ejector running, the loco needs to be able to maintain a vacuum against that small leak.

Tom

 

Whats the purpose of another diesel being hired in? Is it for Whitby cover in the event of another steam ban. Otherwise the railway seems to have plenty of operational diesels, but a lack of available steam....

 

You're not wrong there, Tom.

 

There seems to be conflicting reports on the steam situation one sad that 80136 had some issues, another report suggested that a standard of some sort was running today, so supplementing 5428, 44806 and 926. hopefully 63395 and 92134 will also be back soon.

 

Until the influx for the diesel gala the railway had four operational diesels but only one of which was EVL approved. Because there's only one EVL loco, the red T/T really requires four diesels to maintain the times. With only three locos, the train from Whitby has to arrive first in Pl.2, the loco detach and run through Pl.3 to the north end of the station. The down train can then be let in to Pl.2, the loco detached, run into the sidings and replaced by the Whitby loco. The Whitby train then has to depart before the non-Whitby loco can run through Pl.3 and attach to the up train. It creates havoc with the T/T.

 

Yeah get that. I've been surprised to be honest that they've been doing that with Repton. I'd of thought they would just have had Repton and the Class 31 running the full length of the line on the Whitby sets, but specifying on the daily timetable which one was Steam, and which one was diesel. I suppose they are damned whichever way they go but at least that way customers would have had a full steam option (and a full diesel for those that prefer it), and the railway less struggle to maintain the t/t.

On another note I saw 63395 arrive back at Grosmont today facing Whitby. Would be interesting if it stayed that way when it is running for a while. More options for different photo's etc.

 

Earlier post below answered some of this, though no timeframes on the issues.

If a standard has been on test today hopefully that is 80136 resolved at least. But 5428 also down at the minute. So just Repton, 44806 and potentially 80136 for the moment. I'd hoped that with the length of the steam ban that when it ended most of them would have been available. But I suppose without being able to run them you can't test any fixes or check issues etc.

 

Not my field either but I would have thought that the vacuum load on connecting to a (say) 5 coach train and creating a vacuum on both sides of 10 brake cylinders plus the associated pipework would be much higher than required to maintain the vacuum on a test pipe with an oriface?

 

Not really. There are two factors: what volume do you have to pump out (all the cylinders and all the connecting pipework); and how fast can air leak back in.

If you had a perfect system with no leaks, any pump will eventually pump everything out (down to its own limiting pressure), so the only limit on connecting an arbitrarily long train is how long you have to wait. Which then leaves the question of leakage, and the blank with small hole is calibrated to simulate the typical leakage you would get along a train. If the ejector can overcome that leak and maintain a working level of vacuum, then it should be able to do so on a train of well-maintained carriages.

Tom