Where was it built?
Preston, England, by English Electric.
The preserved blue locomotive is the 1955 prototype DP1.
United Kingdom · Diesel trains
English Electric DP1 Deltic
Diesel locomotive
DP1 Deltic was a British prototype: an engine built to try out a design. It carried two Deltic diesel engines. A prototype helps engineers learn before building a larger fleet.
- Speed
- Still researchingHistorical maximum not verified
- Year
- 1955Reference year
- Maker
- See the train file below
- Job
- Testing a powerful diesel design
Turn it. Take it apart. Discover.
Explore your train
Interactive model loads here. Read the train guide below while it gets ready.
3D modelDrag to turn · Pinch to zoom · Tap a number to explore
What powers a diesel train?
An onboard diesel engine provides power. Some locomotives use a gearbox; others generate electricity for traction motors.
- 1The engine hood and frontOutside the locomotive
The long hood usually covers a diesel engine and its supporting equipment. Passenger railcars can carry their engines below the floor.
Look deeper
The blue DP1 prototype used two Deltic diesel engines. The museum’s 100 mph description concerns the later production fleet, so it is not substituted for a verified prototype speed.
- 2The driver’s cabInside the body
The driver controls the locomotive from this cab. The engine hood is not a passenger area.
Look deeper
Separate locomotives haul coaches or wagons. A self-propelled railcar combines propulsion and passenger accommodation.
- 3Cooling and exhaustOn and inside the roof
Cooling fans help remove engine heat. Exhaust gases leave through an exhaust outlet.
Look deeper
These are diesel engine systems, not electric pantographs. Fan positions and sizes in the model are representative.
- 4How power reaches the wheelsUnder the frame
Many diesels generate electricity onboard to run traction motors. Other types use mechanical or hydraulic transmissions.
Look deeper
Diesel-electric does not mean the locomotive needs overhead wires. Its diesel engine drives the generator.
- 5The fuel tankUsually beneath or within the frame
The locomotive carries diesel fuel onboard. Fuel feeds the engine, which produces the power needed to move.
Look deeper
The tank shown is a simplified storage zone. Passenger railcars and different locomotive types arrange their tanks differently.
Get to know English Electric DP1 Deltic
What is it made from?
Steel and aluminium appear in the museum record.
These material names describe the recorded object; they do not mean that every component uses the same metal.
How does it move — and what is its job?
A 3,300-horsepower diesel-electric demonstrator.
Deltic refers to its engine’s triangular arrangement of opposed pistons. Its success helped win an order for 22 production locomotives.
When was it built?
Built in 1955; withdrawn in March 1961.
It was presented to the Science Museum in 1963. The later production fleet was a different chapter.
What are we still researching?
We leave gaps visible instead of guessing. The original catalogue and our learning model do not establish every real-world specification.
Where does it run — or where did it run?
Known background: United Kingdom. Its job: testing a powerful diesel design. A country name alone does not tell us which line it used.
Is it still running today?
Old photographs and launch announcements do not prove that a train still runs. A whole class may still work even after one member retires. We need a recent operator or museum source.
How power reaches the wheels
Follow these steps, then find the matching sections in the model above.
- 1
Diesel fuel
Energy travels in the fuel tank.
- 2
Engine
Burning fuel makes the engine turn.
- 3
Generator & motors
The engine makes electricity for wheel motors.
- 4
Wheels
Grip between wheels and rails moves the train.
Read the wheels
Co-Co is the arrangement recorded for this exhibit. In common letter notation, B means two powered axles and C means three. A small “o” means the axles have individual motors. Wheel-count and axle-count systems are different, so always check the notation before comparing.
What does its speed really mean?
Historical maximum not verified
The driving game uses an approximate simulation speed. It is not a measured or documented speed for this locomotive.
A fast train is a whole system: vehicle, track, electricity or fuel, brakes, signalling and trained people. A race in the game is a simplified comparison.
What curious kids ask
Can a diesel train be electric too?
Yes! A diesel-electric locomotive uses a diesel engine to turn a generator. That makes electricity for motors at the wheels. It carries its energy as fuel, so it does not need overhead power wires.
Does the driver steer like a car?
No steering wheel is needed to choose a direction. The rails guide the wheelsets. At a junction, movable sections of rail called points or switches guide the train onto another track. The driver controls speed and braking.
Why can’t it stop straight away?
A moving train has energy. Brakes must remove that energy to slow it down. A heavy train travelling fast needs room to stop, so railway signals help keep trains safely separated.
Meet these trains next
Compare how they look, what they carry and where their power comes from.
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DB VT 11.5 Little railway dictionary
Bogie / truck
A frame holding wheelsets beneath a vehicle. It can turn relative to the body to help the train follow curves.
Gauge
The distance between the inside faces of the two running rails. Narrow gauge means closer rails; loading gauge describes the space a train may occupy.
Pantograph
A folding roof collector that stays in contact with an overhead power wire.
Traction
The force used to pull or propel the train. Grip between wheels and rails limits how much force can be used.
Multiple unit
A train with propulsion equipment within its passenger vehicles, operated together from one cab.
Locomotive
A powered vehicle whose main job is to move other railway vehicles.
Shunting / switching
Moving and arranging vehicles in a yard, often at low speed.
Livery
The colours, stripes, logos and other markings painted or applied to a train.
Service speed
The permitted speed for passenger or freight operation on a suitable section. It is not the journey average.
Record speed
A speed achieved on a particular test or record attempt, sometimes with special equipment and conditions.
Tender
A vehicle coupled to a steam locomotive to carry extra water and fuel. A tank engine carries water on the locomotive itself.
Prototype
An early vehicle built to develop and test a design before a production fleet.
Sources & reading
Follow the operator, builder and museum references below for more detail. Links beside an answer show which source supports that answer.
Edition 2026-09-27. Catalogue background is carried forward from the original collection; it is not a new independent verification. Engineering explanations describe principles. Portraits and 3D models are illustrations, with simplified parts and proportions. This is an independent learning guide, not an operator’s timetable.