Surface Lifts: J-bar, T-bar, and Platter Systems
In the world of winter sports, surface lifts serve as essential infrastructure for low-capacity slopes in both expansive resorts and small local ski areas. Unlike chairlifts that carry passengers in the air, surface lifts pull skiers and snowboarders uphill while they remain in contact with the snow.
These systems generally consist of an aerial cable loop that runs over a series of wheels and is powered by an engine at one end. From this main rope, vertical recoiling cables hang down, each attached to a towing mechanism designed to pull the passenger uphill.
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Types of Surface Lift Mechanisms
Depending on the design of the hanger, surface lifts are categorized into three primary types: J-bars, T-bars, and platters.
J-bars and T-bars
The J-bar and T-bar utilize horizontal bars that are placed behind the skier's buttocks or between the legs of a snowboarder. While the T-bar became a significant improvement over the early rope tow, the J-bar has largely fallen out of use at most modern ski areas.
Platter Lifts
Often referred to as button lifts, these systems use a plastic platter placed between a skier's legs. Snowboarders typically position the platter behind the top of their front leg or in front of their chest under the rear arm, holding it in place by hand. While most use recoiling cables, some platter lifts feature rigid poles.
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History and Evolution
The modern mechanism for J-bars and T-bars was invented in 1934 by Swiss engineer Ernst Constam. The first of these lifts was installed in Davos, Switzerland, quickly spreading to other Swiss and French resorts. By 1935, the technology reached New Hampshire and Australia.
In the United States, a J-bar was installed at Rib Mountain (now Granite Peak Ski Area) in Wisconsin in 1937, and the first T-bar arrived at Pico Mountain in 1940. Internationally, the Ski Hoist at Charlotte Pass in Australia dates back to 1938.
The Detachable Poma Lift
A specialized variant of the platter lift is the detachable surface lift, commonly known as a Poma lift after the company that introduced it. This system differs significantly from standard platter lifts in its mechanical operation.
Instead of a retractable cord, Poma lifts use a detachable grip attached to the tow cable, with the button connected via a semi-rigid pole. At the bottom station, the platters detach from the cable and are stored on a rail until a user slides the platter forward to engage it. This design allows for higher speeds; most detachable surface lifts operate at approximately 4 m/s (14 km/h), whereas standard T-bars and platters generally operate up to 3.0 m/s (11 km/h).
The use of a spring-loaded pole in the Poma system helps lessen the acceleration felt by the passenger when the grip attaches to the moving cable.
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Key Facts
- Invented: The modern J-bar and T-bar were created by Ernst Constam in 1934.
- Speed: Poma lifts reach speeds of ~4 m/s, while standard surface lifts typically top out at 3.0 m/s.
- Versatility: Some operators use combined T-bar and platter hangers on a single cable or convert them for summer cycling use.
- Poma Mechanism: Uses a detachable grip and semi-rigid pole rather than a recoiling cable.
Comparison of Surface Lift Types
| Lift Type | Towing Mechanism | Typical Speed | Key Characteristic |
|---|---|---|---|
| J-bar / T-bar | Horizontal bar | Up to 3.0 m/s | Placed behind buttocks or between legs |
| Platter (Button) | Plastic disc | Up to 3.0 m/s | Placed between legs or held by snowboarders |
| Poma Lift | Detachable platter | ~4.0 m/s | Detachable grip with semi-rigid pole |
Frequently Asked Questions
What is the difference between a platter lift and a Poma lift?
A standard platter lift uses a retractable cord attached to a continuous cable. A Poma lift is a detachable surface lift where the platter detaches from the cable at the bottom station and is stored on a rail, utilizing a semi-rigid pole and a detachable grip.
How do snowboarders use a platter lift?
Snowboarders typically place the platter either behind the top of their front leg or in front of their chest under their rear arm, using their hands to hold the mechanism in position.
Who invented the modern T-bar and J-bar?
They were invented in 1934 by the Swiss engineer Ernst Constam, with the first installation taking place in Davos, Switzerland.
Are J-bars still commonly used today?
No, J-bars are no longer used at most ski areas, having been largely superseded by T-bars and platter lifts.
Can surface lifts be used for activities other than skiing?
Yes, some operators install hangers specifically for towing sledges, and some convert their hangers during the summer season to tow cyclists uphill.