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Petition for Waiver of Compliance

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In accordance with Part 211 of Title 49 Code of Federal Regulations (CFR), this document provides the public notice that by a document dated November 13, 2012, the San Diego Trolley Incorporated (SDTI) has petitioned the Federal Railroad Administration (FRA) for a waiver of compliance from certain provisions of the Federal railroad safety regulations contained at 49 CFR 213.57-Curves; elevation and speed limitations. FRA has assigned the petition Docket Number FRA-2012-0088.

SDTI seeks a waiver of compliance from provisions regarding cant deficiency contained at 49 CFR 213.57. Cant deficiency is a technical term describing the imbalance of inner and outer wheel loads when a rail vehicle traverses a curve. With the right combination of speed, curvature, and superelevation (the amount the outer rail is elevated above the inner rail), the loads on both inner and outer wheels will be equal, i.e. balanced. The curving speed corresponding to this balanced state is referred to as balance speed. At higher than the balance speed, the centrifugal force will cause the outer wheel load to increase and the inner wheel load to decrease. The manifestation of this load imbalance is that a lateral throw will be sustained by the passengers when the vehicle is traversing the curve. To counter the imbalance, the superelevation on the curve would have to be increased. The necessary amount of the increase in superelevation is the amount of cant deficiency.

SDTI intends to operate its SD100 and S70 light rail vehicles (LRV) on curves at speeds that will generate a cant deficiency up to, but not more than, 6 inches; but no more than the maximum authorized speed.

In support of its petition, STDI has submitted a report for a cant deficiency dynamic test that is to demonstrate that the LRVs can safely be operated at the requested 6 inches cant deficiency.

A copy of the petition, as well as any written communications concerning the petition, is available for review online at and in person at the U.S. Department of Transportation's (DOT) Docket Operations Facility, 1200 New Jersey Ave. SE., W12-140, Washington, DC 20590. The Docket Operations Facility is open from 9 a.m. to 5 p.m., Monday through Friday, except Federal Holidays.

Interested parties are invited to participate in these proceedings by submitting written views, data, or comments. FRA does not anticipate scheduling a public hearing in connection with these proceedings since the facts do not appear to warrant a hearing. If any interested party desires an opportunity for oral comment, they should notify FRA, in writing, before the end of the comment period and specify the basis for their request.

All communications concerning these proceedings should identify the appropriate docket number and may be submitted by any of the following methods:

  • Web site: Follow the online instructions for submitting comments.
  • Fax: 202-493-2251.
  • Mail: Docket Operations Facility, U.S. Department of Transportation, 1200 New Jersey Avenue SE., W12-140, Washington, DC 20590.
  • Hand Delivery: 1200 New Jersey Avenue SE., Room W12-140, Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal Holidays.

Communications received by January 31, 2013 will be considered by FRA before final action is taken. Comments received after that date will be considered as far as practicable.

Anyone is able to search the electronic form of any written communications and comments received into any of our dockets by the name of the individual submitting the comment (or signing the comment, if submitted on behalf of an association, business, labor union, etc.). You may review DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (Volume 65, Number 70; Pages 19477-78) or online at

Issued in Washington, DC, on December 10, 2012.

Robert C. Lauby,

Deputy Associate Administrator for Regulatory and Legislative Operations.

[FR Doc. 2012-30240 Filed 12-14-12; 8:45 am]