PRIIA Section 305 diesel locomotive requirements

[HarveyK400]

Section 305 of the Passenger Rail Investment and Improvement Act of 2008 (PRIIA) for diesel locomotive requirements would, in my opinion, fall short of current and future needs.

• The allowable cant deficiency of just 6" is only good for 105 mph for 1-degree curves with a cant of 1.5" for a 50 mph for general and heavy-haul freight that would allow 65 mph for priority traffic such as for produce and intermodal.  Even with NEC 4" cant, only 121 mph would be allowed; but many lower-frequency corridors would share tracks used predominantly for freight tonnage.
• This also is inconsistent with tilting capability of passenger equipment in service now such as Talgo and Acela.
• Even the F59 and NPCUs are cleared for 7" cant deficiency; so the Section 305 requirement is undercutting the need.  With a predominance of sharper curves on most existing and prospective passenger corridors, at least some stretches would not be hindered by a 1-degree curve for 110 mph.
• If the expense of complete grade separation is undertaken; the 125 mph limit seems both arbitrary and short-sighted.  150 mph is a more realistic target that would allow higher speeds as ridership and service grow with incremental full grade separation and speed increases for eventual and costly up-front investment in electrification for higher speeds. 
• Such a higher, 150 mph requirement for intercity corridors may not be congruent  the 65,000 pound starting tractive effort needed for heavier trains such as for Chicago-Milwaukee and California corridors and long-distance services with a 4-axle locomotive.  While familiar with the issue, I do not have the expertise to make a recommendation for maximum axle load for speeds up to 150 mph.
• While push-pull operation is important, the power needed to attain 150 mph within 10 miles (somewhat arbitrary) would take two locomotives with approximately 4,000 hp each for traction, so cab cars may be moot with high-speed, tilting services as with Acela.