Performance_Replacement_Amendment_A0004.pdf

SOLICITATION NO. 6923G520RTUGREPLACEMENT

AMENDMENT A0004

October 23, 2019

1. Drawings and Specifications call for a 6-inch Maxim M42 Type I silencer; our CAT dealer has specified the CAT c18 Main Engines are delivered with an 8-in exhaust outlet; and POWERTHERM MAXIM SILENCERS, the manufacturers of the exhaust silencers, does not recommend a 6" silencer for this engine application due to the maximum allowable back pressure of the engine. Instead, they have stated that the engine application would require a 10-inch silencer. What size diameter is required for the main engine exhaust system. This will be a critical question due to space limitations, both in the engine room and in the stacks.

We discovered an error in the backpressure estimate for the silencer that led to an underestimate of the losses. The 6" Maxim silencer (6 M42) with 6" exhaust pipe as specified in our design will not work. However, we have verified by calculation and in our 3D model that an 8" exhaust pipe and an 8" silencer (Maxim model 8 M42) will fit inside the casing and also fall below the maximum allowable backpressure for the engine. A 10" silencer is not needed.

2. Page 45 – The NavNet 3D Black Box is no longer available. Is the Furuno TZT2/BB an acceptable substitution? Is a second radar and display needed to pair with TZT2/BB or is the one radar and display described earlier in the specification sufficient?

The general intent of the navigation system equipment selection was to display GPS, AIS, chart, radar, and depth sounder information on a single monitor to facilitate safe navigation of the vessel and make best use of space in the Pilothouse. This can be accomplished through installation of a Navnet TZTouch2, 15" multi-function display. The now discontinued Furuno Nav Net 3D Black Box (MFDBB) is not required.

3. Page 45 – It is our understanding that the Furuno FE800 does not have Ethernet connectivity. It does have data outputs so that you can have depth on other devices. Is the Furuno FE800 the correct model?

Is Ethernet connectivity required?

The Furuno FE800 is the correct model. The depth sounder transducer shall be integrated into the bridge navigation equipment. Alternative communication methods are acceptable; ethernet is not required to facilitate this requirement.