Stalls are caused by the steam engine losing enough boiler pressure to climb the gradient, as the engine starts to work harder and harder, more steam is being used and the rate it's being generated starts to drop, causing the boiler to lose pressure. As the boiler loses pressure, the brakes start to apply causing the engine to go even slower and thus' making it stall. The steam crew must then wait for the pressure to rise again, to release the brakes and then make an attempt at restarting.
Certainly a reminder that Beasdale bank, 1 in 48, is not to be trifled with! The Mallaig line is very scenic but also a real test for any locomotive. But there are squeals on the first climb that are not there on the second at similar or greater speeds, therefore not just wheel flanges. So I would agree with those who reckoned that the brakes partly leaked on the first time, especially as the engine was blowing off as it stalled. The second time as well as rebuilding steam pressure the driver may well have ensured he was pulling the best possible vacuum before restarting, and the engine slogged steadily up the steepest part.
As I was recording the video I thought "they have left the brakes on" but later I was told it was the sound of the wheel flanges on the curve with the rising gradient. This is plausible as there is a similar sound on the second, successful, attempt at the apex of the curve.
Judging by the sound of brakes, I wonder whether the vacuum failed?
That sound must surely be brakes binding? Not the squeal usually associated with flanges on tight curves
went on that few weeks ago.wonderful trip
Stalls are caused by the steam engine losing enough boiler pressure to climb the gradient, as the engine starts to work harder and harder, more steam is being used and the rate it's being generated starts to drop, causing the boiler to lose pressure. As the boiler loses pressure, the brakes start to apply causing the engine to go even slower and thus' making it stall.
The steam crew must then wait for the pressure to rise again, to release the brakes and then make an attempt at restarting.
Blow up
Certainly a reminder that Beasdale bank, 1 in 48, is not to be trifled with! The Mallaig line is very scenic but also a real test for any locomotive. But there are squeals on the first climb that are not there on the second at similar or greater speeds, therefore not just wheel flanges. So I would agree with those who reckoned that the brakes partly leaked on the first time, especially as the engine was blowing off as it stalled. The second time as well as rebuilding steam pressure the driver may well have ensured he was pulling the best possible vacuum before restarting, and the engine slogged steadily up the steepest part.
Very good footage!
Went on it 2018 emotional.
That sounds as if the pressure was so low the brakes came on.
Fascinating - many thanks for the video response. They got there in the end!
As I was recording the video I thought "they have left the brakes on" but later I was told it was the sound of the wheel flanges on the curve with the rising gradient. This is plausible as there is a similar sound on the second, successful, attempt at the apex of the curve.
Sounds to me like low steam pressure causing brakes to apply and needing to stop for a blow up.
Lose the annoying bagpipes