railfan365 wrote:1. How does the fireman get to the fuel and water in that second tender?
The second tender just carries water. A simple hose connects the two and gravity does the rest. On an oil burning locomotive, it might be possible to store extra fuel in a similar manner to the cab-forwards, but I doubt it has been done on any large scale.
2. Is the diesel locomtoive actually providing power, or is it there in resrve? Thanks.
Several of the large mainline engines (844, 765, 4449, etc.) have M.U. control boxes with cables running through the tenders. Other operations use radio to tell a second crew in the diesel how hard to pull. How much the diesel is used depends on the engineer, length of train, etc. On 765's long ferry moves last year, the diesel was used to conserve fuel.
Sometimes the diesel is there for other reasons. Amtrak sponsored excursions require a diesel to provide electricity for the train's AC and lights. 765 last year needed the diesel to power the cab signals. Finally, it helps with dynamic breaking.