South Devon Banks facts for kids

The South Devon Banks are three very steep parts of the old GWR train line in Devon, England. This line connects the cities of Exeter and Plymouth.

These two cities are separated by the rocky Dartmoor area. Early railway planners had to find a way around this tough land. Isambard Kingdom Brunel, a famous engineer, designed the South Devon Railway. He chose to build the line along the coast, between the Exe and Teign rivers. Then, the line climbs the hills near Dartmoor to reach the Plym river mouth.

From Newton Abbot, trains climb Dainton Bank. From Totnes, they climb Rattery Bank. The highest point is Wrangaton summit. Then, trains go down Hemerdon Bank to reach Plymouth. These three steep sections are together called the South Devon Banks.

Dainton Bank: A Steep Climb

Dainton Bank is the third steepest main railway climb in mainland Britain. It is about 2 miles long. The slope changes from 1 in 36 to 1 in 57. This means for every 36 or 57 feet forward, the track goes up 1 foot.

Leaving Newton Abbot station, the line is mostly flat. It stays flat until Aller Junction. Here, the line to Torbay turns off to the left. The real climb starts at Stoneycombe. There used to be a signal box and a quarry siding here. The climb continues through Dainton tunnel. It ends at Dainton signal box. This section is about 2 miles and 17 chains (3.56 km) long.

Rattery Bank: A Long Uphill Journey

Rattery Bank is the seventh steepest main railway climb in mainland Britain. It is a constant climb of about 4 and a quarter miles (7.44 km). The slope starts between 1 in 45 and 1 in 70. It then gets a bit easier to 1 in 90. After that, it gets steeper again to 1 in 65.

After leaving Totnes station, the train line immediately starts to climb. It goes past where the Tigley signal box used to be. Then it continues to where the Rattery signal box used to be. This whole climbing section is about 4 miles and 50 chains (7.44 km) long.

Hemerdon Bank: The Final Big Hill

Hemerdon Bank is the fourth steepest main railway climb in mainland Britain. It has a constant slope of 1 in 42 for 2 and a half miles. This means for every 42 feet forward, the track goes up 1 foot.

The climb begins at Plympton. It goes all the way up to the Hemerdon signal box. This section is about 2 miles and 50 chains (4.22 km) long.

How the Banks Affected Train Travel

From early times, trains had limits on how heavy they could be. This was because they needed to climb the steep South Devon Banks. Express trains also needed to travel fast between Exeter and Plymouth.

In the old broad gauge days, trains would change engines at Newton Abbot. Special engines, like the GWR's 2-4-0 saddle tanks, would pull trains over the steep hills to Plymouth. This continued even after the tracks were changed to standard size. Later, different types of engines, like the GWR's 4-4-0 Duke class, would take over for the climbs.

The famous Cornish Riviera Express started running in 1904. At first, it was limited to 6 coaches. This allowed a single engine to pull it. But more people wanted to travel. By 1911, even with newer, more powerful engines, an extra engine was often needed. This extra engine, called a "pilot engine," would help pull the train up the hills. It was usually added at Newton Abbot for trains going towards Plymouth. For trains coming from Plymouth, two engines would start. One would be removed when the train stopped at Newton Abbot.

Even the very powerful King class engines sometimes needed help. If the train was very heavy, another engine would be added.

When new diesel trains arrived in 1958, they were powerful enough. They could handle the steep hills on their own. This meant trains no longer needed two engines to climb the banks. Later, even faster diesel trains made it possible to travel quicker over these hills.

Today, HSTs are very powerful. They usually have no trouble keeping to time. However, if an HST is running with only one working engine, it might need help. Another locomotive might be attached to help it over the South Devon Banks. This process takes time. Also, the extra engine limits how fast the train can go.

Now, HSTs are allowed to run with just one working engine. But they might skip the stop at Totnes. This helps them get a good run at the steep hills. This change happened because there are fewer extra diesel locomotives available today.

The Banks as a Test Track

The South Devon Banks have been used for many tests. The GWR and later British Rail used them to see how well new trains performed.

In 1948, different types of steam engines were tested here. They pulled trains from Paddington to Plymouth. These tests included a special car. This car measured how much power the engines were using.

In 1950, a new type of train, a Gas Turbine locomotive, was tested. It tried to restart a heavy train on Hemerdon Bank but struggled. It also had trouble climbing the bank with a heavy load. Another Gas Turbine locomotive was tested in 1951. It performed well on Dainton and Rattery Banks. It also pulled very heavy trains up Hemerdon Bank. It managed to keep a good speed even with many coaches.